:D Genetic Preservation :D - Breeding

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shantibaba​

Breeder and moderator​

• Apr 22, 2019

Article April 2019 La Dolce Vita English version
Title; The Father of Seedbanks, Nevil Schoenmakers died March 30th 2019, and will be forever a legend in the Cannabis World.
Nevil Schoenmakers (The Seedbank), along with Howard Marks (Mr. Nice) and Me, Scott Blakey (The Greenhouse Seed Company) were the founding partners of the old school seed company Mr. Nice Seedbank set up in 1998. I set up the Greenhouse Seed Company with my ex Dutch partner Arjan in 1994, while Nevil had set up The Seedbank in the 1980s, which later was to be renamed The Sensi Seed Bank when Ben Dronkers bought it…the rest is now history.
In 2016 Howard died after a battle with bowel cancer…now in 2019 March 30th Nevil also died from an infection after battling cancer and Hepatitis C for many years. I already miss them both dearly but I will never forget the history we shared and the fun we had on the way to cutting new paths in the Cannabis Industry.
When we all started our individual journeys, the Cannabis industry was illegal, undercover, and a sub-culture that most did not discuss if they were involve or active in it since everyone who knew could compromise the activity! How times changed and attitudes mellowed? Nonetheless, each one of us has had our experiences with the legal system in the days gone by which in some way shaped our futures individually.
Howard was a well known public figure who had the gift of the gab, and made a living giving shows after the illicit days of smuggling. What people may not know about Nevil is the type of person he really was to work with and to be around, as he was more affected by circumstances and stories in the early 1990s than either me or Howard.
Nevil was difficult to read at times and had a somewhat enigmatic presence, demanding seriousness and attention to detail in all he did. His passion for breeding was not only in Cannabis but he bred Budgies, Guppies to feed the birds, Sheep, Coy Carp and Horses. The problem was most of these animals took too long to breed and costs involved were extremely high. Since Cannabis was the quickest and cheapest to breed, Nevil concentrated on this aspect to be able to achieve goals in realistic time frames. I was involved in breeding all my life and when I came to Holland in 1990, and linked up with Nevil we began a long and successful working relationship that changed the course of modern day Cannabis strains used for mainly recreational purposes, at this stage.
I recall one day in Nijmegen when we were in the greenhouse with all the tanks of Coy Carp at different ages….and Nevil turned to me and said he wanted to breed a Coy Carp like the Japanese flag …all white with a red sun in the center….at first I thought he was pulling my leg but he was deadly serious. When I asked why the Japanese Flag…he said that after visiting auction sites and breeding sites the highest value for Coy Carp came from Japan, where they value such fish…and would pay 25000 Euros for a fish like that….so I realized then and there this fish story was going to be an experience. Nevil`s persistence and determination edged him forward …his insatiable reading and devouring of facts and beginning at the highest genetic level possible, was always something important for him. He would locate the best or best known breeder for any of his projects and begin there.
In these days without science on our side we had to trust our own intuition and peers critics. The small clique of people we interacted with included people such as Robert Clark, George Cervantes, Ed Rosenthal, Mischka, Mila, Eagle Bill, Dave Watson, Ben Dronkers, Simone from Serious and so forth….all now people of substance in this flourishing industry.
In the 1980s while I was traveling around Asia/ South America and at University, Nevil open the first Seedbank ever to exist for Cannabis Seed…The Seed Bank. Nevil convinced the Dutch authorities to help him change from drug dependence to businessman and he pioneered the beginning of this evolutionary step in Cannabis Seed commercialism. Like Howard, Nevil was a charismatic professional in a chosen line of work that was unique and cutting edge for that time.
The 1990s was what I call the golden years of Holland, and in this time Nevil and I teamed up and we produced a lot of strains that set standards high in all niches of Cannabis. We were able to use the platform of the coffee shops to release these wares which included the Widow family, Haze family, NL5 series,G13 series, Skunk and Afghan hybrids and so forth….basically we set up many of the building blocks for modern day Cannabis strains.
Cloning changed the game for us and the future of all plant strains. Being in Holland with the mixture of high tech agricultural machinery and techniques added to the café society and lay-back-all-is-possible attitude was the setting of the time…We were young, free spirited and loved Cannabis and its diversity to a point we were all pushing each other to come up with something stronger and more aromatic than the previous…till we reached knock out point with THC strains. We won so many awards in these times and created a following and a new generation of avid breeders of Cannabis…world-wide.
Due to the lack of science in that decade, these strains we successfully introduced each year in the High Time Cannabis Cup via Coffee shops and came out of trial and error and our own opinions of what was worthy to breed with and what was in demand. These strains were a combination of work passed down to us from different corners of the world and from extremely dedicated people who spent their lives delving into finding the Holy Grail of Cannabis.
Funnily, both Nevil and I were Australians and Aquarians from opposite sides of the continent that both ended up in Holland doing what is still considered an illegal job in Australia to this day? But in Europe, USA and the rest of the world we became well known for the work we did and do in Cannabis. We needed to leave Australia to do what we did and do and this always bothered us both…and probably always harped on our subconscious. It was the point of not being understood and appreciated for doing a good job on something before its time, but the drive was stronger to achieve a goal than to explain, so in the 90s it was the freedom of Holland that won our hearts.
Nevil, Howard and I all shared traveling to faraway places to adventure into the unknown, meet extreme people and be given responsibilities most would turn their toes up to but we somehow managed to turn these events into positive advancements in all walks of life. We all shared unspoken mutual respect for each other and what we all did and achieved. It remained understated and calm within our group and we were all happy to create new things or feelings or moods not driven by only the money aspect but moreso by the true meaning to make something that never existed before…money always came when we hit that completely, and we all together and individually hit it on several occasions.
There was an unglamorous side to our work and we all passed through this. Nevil being the first to send seed worldwide created invisible enemies blinded by envy and motivated by greed and it took a toll on him over time. While Nevil got on with projects and tried to put the negative past behind him and focus on the positive future there were times when he fell into depression and suffered silently. He became reclusive on a few occasions, one being after the jail time in Australia in 1990 and the other in 2005 after finishing all his ties with Holland business…but he never stopped working.
Nevil had a few children with several partners over his life and he did his best to try and be a long distance father. I believe the distance eventually lead him back to Australia to be close to his family as he grew disenchanted with people and the industry in Europe.
When in 2007 I created the CBD crew and made the decision to go forward in to the medical side of Cannabis along with Howard, Nevil declined the offer and preferred to remain in Australia and work quietly on some breeding projects he never was able to conclude due to his illness. I have his old seed, his plants and his notes and in time will find people to pass things on to, as there is only so much time we all have on Earth that is the limiting factor.
Nevil loved the motto for Mr Nice Seed Bank, More Plants less People as he also chose some disappointing partners early on in his working life. Plants could always be relied upon, people less.
Nevil was exchanging seed with Dave Watson early on with skunk and Haze projects, and when they finished their projects together there was conflicting stories that arose from gossiping stoners…but no one should be too quick to believe anything as it was a different time. What Nevil and I always agreed on was that no matter what the story is, proof is in the seed and this will be the judge, ultimately for those who use our seeds.
It is not often to find people in your life that you look up to and feel equal in all respects to…but I can say I had the honor of two such gentlemen, Howard and Nevil, both very different people, but both wonderful professionals in an unprofessional world.
Nevil was a pioneer and forged a path many followed with love and passion to this day. He was my friend and confident and I will miss him and his unique prospective on the world of Cannabis. The world is a better place after having had the presence of Nevil Schoenmakers, a true pioneer and now legend in the world of Cannabis…RIP my dear friend….Shantibaba.

 

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Selective breeding for shorter plant stems contributed to ‘Green Revolution’ yield gains​

John Innes Centre | August 25, 2017

Orville Vogel compares Gaines wheat (left), which he developed, with Omar wheat, a traditional variety. Vogel's introduction of semi-dwarf genes increased yields by 25 percent.
Untangling the genetics that control and regulate the yield of a crop is a complicated, but potentially rewarding puzzle. High-yielding dwarf varieties of wheat and barley were developed in the 1950’s and 60’s, during the “green revolution” when plant breeders selected for mutations that were short-stemmed.
Plants with shorter stems are less likely to fall over in the field, and as a result greater yields are harvested. These new variants, of crops such as barley, wheat, and rice had the beneficial shorter stems, but inadvertently also included another important trait that reduced the potential yield of the crop.
Professor Robert Sablowski and his team at the John Innes Centre study the role of DELLA proteins, which cause a range of growth responses in plants. It was mutations of the DELLA genes that the breeders of the green revolution were selecting for in their efforts to increase yield through reduced stem length.
…
This breakthrough means that plant breeders can now select for new mutations that separate the desirable and undesirable traits conferred by DELLA proteins – short stemmed crop plants with larger meristems. Successfully selecting for both would increase the potential crop yield, helping to address global food security challenges.
[Read the full study here (behind paywall)].
The GLP aggregated and excerpted this article to reflect the diversity of news, opinion and analysis. Read full, original post: Green revolution genes promise additional yield

Selective breeding for shorter plant stems contributed to 'Green Revolution' yield gains

Untangling the genetics that control and regulate the yield of a crop is a complicated, but potentially rewarding puzzle. High-yielding dwarf varieties of

geneticliteracyproject.org

 

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[CITATION] The History and Evolution of Milo in the United States1​

RE Karper, JR Quinby
Agronomy Journal, 1946•Wiley Online Library


MILO, a group of Sorghum vulgare Pers., has consisted of an everchanging number of varieties in the United States during the first 40 years of the present century. Coincident with the first development of agriculture and settlement in the Southwestand until only four or five years ago, milo has been the basic grain crop. The several commercial varieties of milo have comprised 7 5 to 8o% of the grain sorghum crop in Texas, and th~ y have been almost equally as important in Oklahoma, Arizona, New Mexico, California, and southwestern Kansas. This is indicative of the general excellence of adaptation to the region inherent in this group of grain sorghum and the superiority of its several varieties which have come about spontaneously following mutations or have been developed through crosses between the various strains and varieties.
Milo apparently was introduced into the United States as one variety about 6o years ago, but there are now numerous varieties that have originated from no less than seven mutations and recombinations of these mutations. As a result of recent research, the genetic basis for the distinctive maturity dates of the various milo varieties has been disclosed (9), 3 and with the closing of this gap in our knowledge of the important characteristics differentiating the various strains and varieties of milo, it is now possible to reconstruct with some assurance of accuracy the genesis and evolution of these varieties as they have sometimes mysteriously appeared, or even disappeared, during the past half century. It appears now to be worth while to record the very interesting evolution in this plant group which has been taking place, largely spontaneous in nature, but under the eyes of both planters and agronomists. Although little understood or slowly recognized at the time, yet the new forms were readily accepted and utilized to our economic advantage in true American fashion. Not only can the somewhat speculative history of the milo group of varieties now be considerably clarified, but the important role of mutations in the development of crop varieties can be brought into proper focus. Also, it is not unlikely that a similar development is typical of the way varieties of other plant species have come and are coming into existence.

A single plant with a dwarf mutation is now a single commercially grown strain

Strain: Bushmans
Breeder: Herbaria
Location: Indoor
Upload date: 18.08.2010
Picture from: ananda

Indoor: 45 - 50 days
Outdoor: mid to end September
Genetic: 100% sativa
Origin: South Africa (Ciskei)

Introduced to Africa circa? None the less exhibiting full sativa effect... little to no cbd ?

 

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G13 ndnguy- seed from ole miss ag center labeled "lot 13"

Sativa_pheno_57_days​

mazarindtermine7ba​

Marijuana Research | The University of Mississippi

pharmacy.olemiss.edu

History​

1908​

– University of Mississippi School of Pharmacy was founded by pharmacist Henry Minor Faser, the first dean of the school.

1964​

– Research Institute of Pharmaceutical Sciences (RIPS) was established as the research arm of the School of Pharmacy with a mission to discover and develop new drugs from natural sources.
– Chemical structures of THC and CBD were determined by professor Raphael Mechoulam of the Hebrew University of Jerusalem, spurring a worldwide interest in cannabinoid research.

1968​

– Program committee of National Institute on Mental Health (NIMH) offered a contract to provide standardized marijuana for researchers. Dr. Norman Doorenbos, chair of UM Department of Pharmacognosy, applied for and was awarded the contract.


– Dr. Coy Waller joined UM as associate director of RIPS.
– First experimental plot of marijuana was grown at the UM site, using seeds from Mexico, Panama, Southeast Asia, Korea, India, Afghanistan, Iran, Pakistan and Lebanon.

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1969​

– A secured garden was constructed for the first substantial crop grown at the UM site. An additional plot was planted in southern Mississippi on UM forest lands.

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1970​

– Dr. Carlton E. Turner joined the project as a postdoctoral Research Associate to manage the development of cultivation techniques for standardized marijuana.
– Congress passed the Controlled Substance Act, making marijuana a Schedule-I drug.
– Dr. Coy Waller became director of RIPS.

1973​

– Congress established the Drug Enforcement Administration (DEA) to be the lead agency for enforcement of the Controlled Substance Act.

1974​

– National Institute on Drug Abuse (NIDA) was established under the Alcohol, Drug Abuse, and Mental Health Administration.

1975​

– NIDA and DEA collaborated to monitor the potency of illicit marijuana by establishing the Potency Monitoring Program as part of the contract.
– Dr. Mahmoud ElSohly joined the project as a postdoctoral research associate.

1976​

– Outdoor cultivation activities continued to expand as the program became well known internationally.
– Over 100 varieties of cannabis seeds were planted this season.
– UM hosted the United Nations Narcotics Symposium in August.

1977​

– Because of potential health risks of smoking Mexican marijuana sprayed with the herbicide paraquat, NIDA incorporated paraquat testing into the Potency Monitoring Program.

1978​

– The Compassionate Investigational New Drug program was established to provide marijuana cigarettes to treat certain medical disorders in a limited number of patients.

1980​

– Tobacco drying barns were installed at the garden for drying the crops, instead of drying the harvested plants in the sun, as was done previously.

1981​

– Dr. Turner left UM to become the Director of Drug Abuse Policy under President Ronald Reagan.
– Dr. ElSohly became the director of the UM marijuana project.

1984​

– Experimental techniques were developed to grow “sinsemilla” (Spanish for “no seed”) in which only female plants are allowed to mature in order to develop dense buds with high concentrations of cannabinoids. Today this is the predominate cultivation method for production of drug-type marijuana.

1989​

– The Coy Waller Laboratory Complex was constructed to provide dedicated laboratory and horticulture space for the project.

1991​

– RIPS began development of a novel drug delivery system for cannabis: a suppository containing a THC derivative.
– RIPS developed a chemical “fingerprint” technique to identify the country of origin of confiscated marijuana.

1992​

– NIDA became part of The National Institutes of Health.

1995​

– The National Center for Natural Products Research (NCNPR) was established under RIPS with missions to improve human health and agricultural productivity through discovery, development and commercialization of natural products.

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1999​

– NIDA’s Request for Proposals (RFP) included requirements for GMP production. NCNPR established new quality systems and hired additional personnel in order to meet the new requirements.

2000​

– The Coy Waller Laboratory building expanded with the addition of an annex with an indoor growing facility, a second vault and a plant processing laboratory.

2005​

– NCNPR acquired an additional DEA Schedule-I bulk manufacturer to provide cannabis extract to pharmaceutical companies.
– 1,500 kg of marijuana was produced this year in the outdoor garden.
– The grow room was renovated with a new HVAC system.

2006​

– NCNPR submitted Drug Master File “Cannabis Extract” to FDA.
– An additional 1,500 kg of marijuana was produced this year for preparation of THC-rich cannabis extract.

2007​

– Over 300 kg of the product THC Cannabis Extract was manufactured this year.

2012​

– School of Pharmacy researchers developed a transmucosal patch for the delivery of THC using THC prodrugs.

2014​

– Three cannabis varieties were grown this season, yielding over 600 kg of marijuana of different chemical profiles for the NIDA drug supply program.
– NIDA announced RFP for their ongoing marijuana program; UM submitted a proposal.
– NCNPR and Nemus Bioscience collaborated to develop CBD analogs and THC prodrugs.

2015​

– Mississippi governor signed “Harper Grace’s Law” to allow NCNPR and UMMC to undertake a clinical study of CBD cannabis extract in treatment of pediatric epilepsy.
– NCNPR won an award of a five-year NIDA contract, but Potency Monitoring Program was no longer included in the base contract.

2016​

– DEA announced a new policy to allow marijuana growers outside of the NIDA program to provide materials for research purposes.
– NCNPR submitted Drug Master Files “CBD Cannabis Extract” and “Cannabidiol” to FDA.
– NCNPR developed “CBD Cannabis Extract Oral Solution” for UMMC clinical study.
– The grow room was renovated to include new lighting technologies.

2017​

– UMMC pediatric neurologist Dr. Brad Ingram submitted the Investigational New Drug (IND) application to FDA for a clinical study to explore the use of CBD Cannabis Extract Oral Solution as a treatment for young epilepsy patients.
– FDA responded to Dr. Ingram with approval to proceed with the UMMC study.

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2018​

– UMMC Institutional Review Board gave Dr. Ingram approval to begin the CBD Cannabis Extract Oral Solution clinical study.
– The 2018 Farm Bill was signed into law, allowing farmers to cultivate cannabis plants that meet the legal definition of “hemp.”

2019​

– At a location off-campus, NCNPR grew an experimental crop of hemp under federal farm bill regulations.
– At the campus garden, NCNPR grew three varieties of cannabis for the NIDA Drug Supply Program.
– USDA published a final rule that provides regulations for the production of hemp in the United States.

2020​

– Due to promising results with the young epilepsy patients, FDA approved Dr. Ingram’s request to extend the CBD Cannabis Extract Oral Solution clinical study for another two years at UMMC.
– Mississippi governor signed legislation to allow the cultivation of hemp in the state by farmers following the USDA regulations.
– Mississippians voted to approve a ballot initiative that would allow a medical marijuana program in the state.
– DEA published regulations to allow “Bulk Manufacturer” registrants to cultivate marijuana for research purposes.

2021​

– NCNPR conducted a clinical study to measure the pharmacokinetics of CBD Cannabis Extract Oral Solution in healthy volunteers.
– Mississippi Supreme Court ruled that the state’s ballot initiative process was outdated, which effectively overturned the state’s medical marijuana initiative.
– Two tunnel houses were constructed in the UM Marijuana Garden to enhance outdoo

 

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THE
POPULAR SCIENCE
MONTHLY

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JANUARY, 1905.

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SOME EXPERIMENTS OF LUTHER BURBANK.

By President DAVID STARR JORDAN,

LELAND STANFORD JUNIOR UNIVERSITY.

MR. LUTHER BURBANK, of Santa Rosa, California, is doubtless the most skilful experimenter in the field of the formation of new forms of plant life by the process of crossing and selection. He is the creator of many of our most useful plant forms: roots, nuts, fruits, grains and grasses, as well as of many of our most beautiful flowers. His methods are the practical application of the theories of Darwin and his followers, and to a degree wholly exceptional among plant breeders, Mr. Burbank has kept in touch with most modern work in the field of bionomics, and very much of his time and energy is devoted to experiments of scientific interest not likely of themselves to yield immediate practical results. In the nature of things, the demands of his work, and the necessity for the sale of new forms produced by him, have prevented the keeping of detailed records of his work, although steps have been taken toward the provision of explicit records in the future. For the rest, Mr. Burbank's success in practical achievement gives weight to his views on theoretical questions.

The present writer has recently at different times spent three days in Mr. Burbank's company at his gardens at Santa Rosa and Sebastopol, keeping note of things seen and of Mr. Burbank's views concerning them. In this paper, selections are made from these notes, the forms of plants referred to having been examined by the writer and the report of explanations having been verified by Mr. Burbank. All quotation marks refer to conversations with Mr. Burbank, the statement of which Mr. Burbank has verified or corrected. The accompanying illustrations are all from photographs by Mr. Burbank.

Sample Leaves of Common Garden Dahlia (Dahlia variabilis), Showing Ordinary Variation within a Species when under Cultivation.

The process of formation of new types may be grouped under four heads: selection, crossing, hybridization and mutation (or saltation). The process of artificial selection is used in all cases, those varying strains likely to prove useful being preserved, the others destroyed. The word 'crossing' may be advantageously used for the mingling of strains within a species, and 'hybridization' for the breeding together of members of different species. The name 'mutation' (or preferably 'saltation') is applied to sudden changes of characters for which no immediate cause is apparent.




Not many of Mr. Burbank's results are due to unassisted selection, as the processes of crossing and hybridization save time by the increase of the rate or degree of variation. There is, however, no evident limit to the results to be obtained by simple selection. New and permanent species of wheat have, without a shadow of doubt, been produced by selection alone.

In the California poppy (Eschscholtzia californica), stripes of crimson are never seen on the inside. Mr. Burbank once found a seedling in which the outside crimson had struck through like a crimson thread which had been misplaced. In other generations, by selection, this red was more and more increased, until finally out of it is developed a crimson poppy, of which Mr. Burbank has now many specimens, seeding more or less true to the type. The 'Shirley' poppy (Papaver rhæas) is well on the way to blue by selection.

It is questioned whether competition in minor details, or 'intraspecific selection' can form species permanent as wild species are. As to this, Mr. Burbank notes that the cultivated species produced after the fashion of his crimson eschscholtzia 'have a very brief history compared with the wild species, and, moreover, they are constantly being placed in a new environment by man, being influenced by new soils, new climates, new fertilizers and the like. "Breeding to a fixed line will bring fixed results. Man's desultory breeding is brief, the struggle for existence is mostly absent, and new ideals and new uses are required instead of ability to endure under natural conditions. Man's efforts at selective breeding are fluctuating, with frequent saltations."

Dr. De Vries notes that in the common sugar beet, which is a biennial species, there are from one to ten per cent, of plants which bear seed the first year. None of these is ever chosen for seed, and yet the long-continued process of natural selection has never succeeded in rooting them out. As to this Mr. Burbank observes: "This long-fixed tendency to insure continued existence in the past is not yet bred out. Analogous to this is the tendency in flocks to produce black sheep, and the appearance of zebra stripes on horses—ancestral traits not yet bred out."

From the pale yellow Iceland poppy (Papaver nudicaule) are developed white, yellow and orange forms, and some with striped petals and a strong tendency to become double. Selecting the Iceland poppy for size alone, flowers three and one-half inches across have been developed. A large scarlet poppy, Papaver glaucum, closes its two inner petals when a bee or two have entered, shutting in the bees, which buzz angrily and cover themselves with pollen until they are set free. If not visited by bees, the flowers do not close.

A wild form of one of the Liliacæ, Brodiæa terrestris, was made white by selection of the palest among the pale wild ones. Brodiæa lactea taken from the high Sierras where it is a dwarf, becomes, after two years of cultivation, more than twice as high as the original stock, but not nearly as high as the same species grown in the valley.

"Crossing is done to secure a wealth of variation. By this means we get the species into a state of perturbation or 'wabble,' and take advantage of the 'wabbling' to guide the life forces into the desired habits or channels. The first crossing is generally a step in the direction in which we are going, but repeated crossing is often necessary and judicious selection always necessary to secure valuable practical results. Crossing may give the best or the worst qualities of the parent, or any other qualities; and previous crossings often affect the results."

Primus, the First Fixed Rubus Species Artificially Produced.

"Hybridization differs from ordinary crossing only in degree. A species is only a race which has assumed greater fixity. The purposes and results of crossing within the species and of hybridization of different species are essentially alike. The formation of the new individual by the sexual relation of two parents is in itself a species of crossing, giving each new individual in its degree new traits or new combinations."

"Bees and other insects, as well as the wind, cross plants, but they do not work intelligently, therefore rarely to any advantage economically to man. No mechanic could invent such devices as those which tend to prevent self-crossing in plants. All evolution and improvement are dependent on crossing, therefore nature has produced more wonderful devices for this purpose than for any other."

"Mutations, or saltations, are often found; that is, fixed forms springing up, generally from unknown causes, forms which are not hybrids, and which remain constant; as, for instance, colored flowers which yield white forms, these yielding white constantly in their progeny. These mutations can be produced at will by any of the various means which disturb the habits of the plant. It comes out when the conditions are ripe. New conditions bring out latent traits. I should expect mutations to arise in the American primrose and most other plants under wholly new conditions. Extra food or growth force as well as crossing favors variation, as does abrupt change of conditions of any kind. Five or six generations will usually fix a mutation. Sometimes it is fixed at once."




"On the average, perhaps about six generations fairly fix a variation, but this varies greatly, depending upon previously acquired hereditary tendencies. Bringing a species into a new environment disturbs



Leaves showing a Number of Strawberry-Raspberry Hybrids and a Cluster of the Blossoms.

its fixity. Rich soil especially gives rise to variations in growth which seem to be new, and by repetition become inherently fixed. Sometimes ancestral states are brought about by good soil; sometimes (perhaps oftener), also, by starvation; new variations oftenest by rich soil and general prosperity. There is no evidence of any limit in the production of variation through artificial selection, especially if preceded by crossing. Mutations are probably due to the sudden appearance of latent tendencies in new combinations, producing novel effects analogous to new chemical combinations."

"Mutation is not a period, but a state induced by various hereditary and external conditions. It is not by any means certain that there is any period in the life-history of the species when it is more subject to mutation than at other times, other conditions being similar. By crossing different species we can form more variations and mutations in half-a-dozen generations than will be developed by ordinary variation in a hundred or even a thousand generations."

"The La France and some other roses, as well as dahlias, callas and many other plants, every once in a while throw out, on some particular year, a number of unusual sports in various localities. This is probably a matter of season, the forces outside bringing about parallel mutations. The evolution of species is largely dependent on crossing the variations contained within it. Forms too closely bred soon run out, because generally only by crossing does variation appear. It is of great advantage to have the parents a certain distance apart in their hereditary tendencies. If too close together there is not range enough of variety. If too far apart, the developed forms are unfitted for existence because too unstable. Correlated changes work together to produce the effect of mutations. Environment effects a permanent change in species by selection of those which fit it or by producing changes in individuals which are better equipped to survive. Heredity is the sum of all past environment, conditions both latent and apparent. Latent traits often arise when circumstances make them possible. Environment of a lifetime does not necessarily or usually appear in another lifetime, but continues in the same direction and will strike into the nature of the plant in time. We may refer to Emerson's remark on the 'baking into the picture of the pigment laid down by environment.' Selection is 'cumulative environment.' Fortuitous variations occur everywhere. They come up all the time, from past environments, past heredity and present opportunity. No two individuals are alike. Where there is a marked tendency in one direction, we have the case of a persistent effect of environment. Monstrosities are engorgements of force. They are generally a thousand times more likely to. develop another sort of monstrosity than normal individuals are. You are likely to get from sports and monstrosities either extreme of variance. They do not, however, maintain themselves, because heredity pulls back their descendants. A wide variance is more easily pulled back than a slight variance. There are cases where the monstrosity might pull back its species. This is more likely to happen if the forces of natural or artificial selection were in its favor. There are many cases where the variant in minor points is prepotent and outweighs the original stock. Monstrosities produced by crossing often perpetuate themselves as well as the species does."

"One difficulty with the mutation theory of Dr. De Vries, in my opinion, is lack of sufficiently wide experimentation. Fuller investigations will certainly show that the 'sports' or 'chance' variations come under the same law as that of 'fluctuating' variations, mutations being only fluctuating variations carried beyond the critical point where past fluctuating variations can not withstand the accumulated forces without disintegration, thus bending them in a new direction."

"Professor Hubrecht is certainly in error in stating that the mean fluctuations can not be carried into the extreme or 'sport' variations by selection. Professor Hubrecht speaks of two divergent processes, 'fluctuating variations' and 'mutations' which he says: 'Darwin has not sufficiently kept separate.' They are not separate; one is only a tendency toward the other, and which continued, though latent, may, or will, at last become dominant, so as to swing the fluctuating variations fully out of the old orbit into the 'mutation' or 'sport' condition. Radical changes of environment for a series of generations will produce a tendency to sport, but hybridization will bring it about far more abruptly, and for practical plant or animal breeding or for scientific study of all these variations, far more satisfactorily."

" The misunderstanding evidently comes from not having a clear knowledge of latent and dominant hereditary forces. A knowledge of these explains the whole matter and makes harmony between Darwin and Wallace, leaving Professor De Vries's careful experiments good, but coming to different conclusions on the results."

"Professor Hubrecht also states that 'now for the first time—forty years after the appearance of the 'Origin of Species'—the actual birth of a species has been observed by him.' As I have produced several good species by hybridization, as good as nature herself has produced, and as others have done the same by selection alone, the above sentence is hardly true. But as before stated, hybridization followed by selection is the shortest plan by which valid new species can be produced. In other words, the 'period of mutation' can he produced at will!"

"The mutation theory of the origin of species seems like a step backward towards the special creation theory, and without any facts as yet adequate to support it as a universal theory, however valuable and suggestive the experiments of Dr. De Vries may be."

"There is a remarkably close analogy between hybridization and grafting. Bringing. over from France a prunus (P. mirobolana var. pissadi), of which there was no other specimen in America, it was grafted on to the Kelsey plum, a variety of Prunus triflorus. The graft itself did not bloom, but the presence of the graft brought about in the tree a cross of the two species. This is the only case known to me in which the graft affected the reproductive system of the plant, forming a cross between forms which had never crossed. Many hundred descendants of this cross are now living. Darwin accepted with reservations the account of the graft hybrids in potatoes, and there still remains some doubt of reliable testimony of the supposed fact. He also speaks of a now well-known graft hybrid of a yellow and purple cytisus, which is perhaps the most remarkable fact in this line on record."




Diagram showing the Zone of Life and Parallelism of Results in Crossing and Grafting. (L. B.)

Utter refusal to unite under any circumstances, either by crossing or grafting. (Outside of zone of possible union.)

	Pollen acts as a poison.		Grafts blight and die as if poisoned.
Union partial, mosaic or temporary; seed rarely produced; seedlings generally inherit tendencies and qualities of one parent only; second or later generations revert fully.		Grafts often form a temporary union but are not in a normal condition. Avoided by nurserymen and planters with great care, as results are often disastrous to the grower.
Union free; seedlings show unbalanced condition, varying widely; often unusually vigorous; best condition for scientific or natural selection. Good qualities can be made permanent to the race.	Mendelian or Mutative State.	Grafts unite readily but separate under unusual stress—drought, overbearing, lack of nourishment, etc. Avoided by nurserymen and planters.
Unite freely; seed of superior germinating quality produced abundantly. Seedlings normal with ordinary amount of variability.	Unusual Variation.	Grafts unite readily, thriving well; sometimes better than when grafted on their own stock.
Ordinary plant life as oftenest met with.	Normal.	Grafts unite and thrive as we oftenest see them.
Self-fertile; seed produced, but as there are very limited opportunities for profitable variations, this state ultimately ends in		Grafts grow on their own roots.
Extinction.

All these varying states shade off from one to the other, with few hard and fast lines of separation.




"In some directions the strains of heredity are much more unbalanced than in others. An impulse from outside forces may bring about new combinations. This is illustrated by De Yries by a ball with many facets, which, if lightly touched, will return to its original position, if vigorously touched will turn over. Burbank once crossed a pole bean (Phaseolus vulgaris) with a lima bean (Phaseolus lunatus var. macro-carpus). There was no visible effect in the appearance of the pod or the bean, but, when planted, each bean developed a cotyledon, part of one species and part of the other. The lima bean represented the end of the cotyledon, and was united to the lower part by serrated edges; below was the smaller and striped cotyledon of the pole bean. The cotyledons finally parted at the joints between the two, the upper portion falling off, as is often the case with grafts which are uncongenial. The forms were tremendously vigorous, but all came back to the common pole or horticultural bean after the second generation, as though it were an uncongenial graft hybrid, the alien portion being finally entirely rejected. It often happens in grafting, that the branch will be united thoroughly at the point of grafting, but in great stress,. as the overbearing of fruit, the grafted portion will separate and entirely fall off."

"In one sense, hybridization is only a mode of grafting, both being a more or less permanent combination. The different results from hybridization are shown in the diagram below."

"Where the plants are very different, having a different line of descent, and consequently different structure, there will be no hybridization at all. From this we have every gradation to the point where the individuals are very closely alike, and here we have scarcely any variation at all in the progeny, a condition which favors extinction. Again, in grafting, we have every intergradation between total inability to unite and absolutely perfect blend."

"Sometimes a graft strengthens a plant by increasing the body of foliage and thus strengthening the roots. Grafting a Japanese pear on the Bartlett pear will give the latter new life through the increase in the foliage, which gives material for root action and further extension."

As illustrations of the results of crossing and hybridization, the following notes were taken on plants in Mr. Burbank's gardens:

In the beginning of his work Mr. Burbank crossed all sorts of beans and had a half acre of them. Some climbed to the height of twenty or thirty feet, producing all sorts of pods—some with pods long and slender and stems so short that the pods doubled up on the ground. These forms could have been fixed in time, though the variations were unusually persistent and very amazing in their variety and abundance.

Crossing the red and white pole bean, two or three of the beans grew large and bore striped pods, the beans themselves being jet black. From this cross many varieties were developed having all the colors known in beans.

The results of selection are often so simple as to form a mathematical rule, as in the case of Mendel's peas, which holds good with the tribe of peas (Pisum), but not generally with others so far experimented on. At other times they are so complicated that to follow them requires the highest skill, or may be utterly impossible.

A rubus (R. cratægifolius) from Siberia has fruit the size of a large half pea, brownish, seedy and tasteless. Hybridizing with the California blackberry (R. vitifolius), some of the hybrids have the best qualities of both berries combined, and a perfect balance of characters. Out of over five thousand second generation hybrid seedlings, every one is true to the seed. This refers to the Primus blackberry, which is now fully as true a species as any classified species of Rubus.


Stems of Blackberry-Raspberry Hybrids.

The raspberry has been hybridized with a strawberry: the results were thornless plants with trifoliate leaves looking like a strawberry plant and sending out underground stolons like the strawberry. At last, however, the plants send up canes three to five feet high bearing panicles of flowers more profuse in number than those on either parent. After flowering the plant never produces a berry, the fruit forming a small knob, with no effort at maturity.

In the hybrid of the strawberry and raspberry, the resultant plants bore three or four times as many flowers as the raspberry, seven or eight times as many as the strawberry.

Tendencies strong in the parent, even though for a time latent,



Leaves of Blackberry-Raspberry Hybrids.

usually come out strong in the descendants. Ordinary hybrids of forms closely related generally form a perfect blend from both parents. When the parents are far apart all sorts of variations occur, the so called Mendelian condition being one phase of the results.

Hybridizing the iceberg white blackberry with the Cuthbert raspberry develops a plant with foliage and growth midway. About half the plants bear fruit which is red like the raspberry, about half bear fruit which is white like the iceberg blackberry; the quality is midway between the blackberry and the raspberry. In the crossed fruit (first generation) the flavor is not superior, but it is quite intermediate between blackberry and raspberry. The form of the receptacle is intermediate. Some of the fruitlets separate at the base, but not above. In crossing it makes no difference which sex is taken as the male parent; it all depends upon the hereditary tendencies of the sex.

Crosses of wild species yield results similar to those from cultivated species, hut the latter are more available. The white blackberry is a wild variation crossed with the Lawton for size and vigor; the result is a



Leaves of a Blackberry Hybrid, all grown from Seed of One Plant.

much clearer white than the wild one, larger, and very much more productive, in these respects fully equal to its staminate parent, the Lawton.

Apples brought up from the south temperate zone are entirely confused here, yielding leaves, buds, flowers and small apples at various seasons. One of these apples in time, however, became adapted to the conditions and developed into one of the best apples in Mendocino County.




"Animals or plants changed by transference from one country to another never quite go back to the old conditions, even if placed in them again, as hereditary tendencies acquired under the new environments, even though latent for many generations may be called forth again under favoring conditions. Exceptions seem to be as important as the rules in this work. Nature leaves so many loopholes that there is almost no rule without exceptions. She does not tie herself up to any unvarying conditions. Adaptability is more important than perseverance."

A blackberry plant with an immense mass of fruit developed from a seedling from the Himalayas. One plant covers 150 square feet, is 8 feet high, and has a bushel or more of fruit. This is only a young, small plant; when full grown this variety is many times larger.



Apples—all Seedlings from One Variety, 'The Early Williams,' showing about the Normal Variation of Apple Seedlings.




Seedlings of Japanese Quinces, showing Normal Variations.

A purple larkspur reared by Mr. Burbank is produced by crossing a native blue with a native scarlet, the color being entirely a blend. The blackberry was crossed with apples and with all the various rosaceous plants. Over five thousand plants were produced. The apple-blackberry cross came out essentially apples in foliage and growth, though raised from blackberry seeds. Only two of them ever bloomed, all were thornless, one of them bearing rose-colored flowers. From the mountain ash and blackberry a salmon-colored fruit with no thorns and no albumen in the seed was developed. A hybrid between the English and the black walnut grows fully four times as fast as the English walnut; The Original and Improved (Shasta) Daisy. it bears little fruit. The seedlings from the fruit produce some English, some black, and some hybrid walnuts, and not rarely entirely new forms. Crossing often brings about great vegetative life at the expense of reproductive life, or the reverse. The young (second generation) hybrids of the black walnut and the English walnut show very great variation in their leaves, resembling neither parent. The hybrids of the English and California black walnuts are most rapidly growing trees and unusually productive. The first hybrid, of the English with the Japanese walnut, Juglans sieboldi, is largely like the Japanese in the nuts, but rather more like the English in foliage, the second generation being very variable as usual.

By crossing types already crossed, we may often bring out the original stock which had been lost in cultivation. The English walnut has usually five leaflets, the black walnut fifteen to nineteen. The first



Japan Walnut. Result of Cross of the Two. English Walnut.

generation hybrid has eleven, with a fragrance to the leaves that no original walnut has. This tendency or trait is just as real as any other. The American walnut (Juglans nigra) and the California black walnut (J. californica) are closely related species and when hybridized yield fruit of very large size and in enormous quantities.




Descendants of hybrids usually revert to either one or the other parent or break up in all directions. A cross of the eastern black walnut (Juglans nigra) with the California nut (J. californica) yields a hybrid which is a very great grower. From the seed of this tree a surprising variety of mutations are developed, not only resembling


Leaves from Second Generation Seedlings from Cross of Common Persian Walnut (Juglans regia) and California Native Walnut.
every possible combination of both parents but numerous strange forms. In fact, among about two thousand seedlings now alive, almost every type or form of walnut foliage may be found. There are startling variations in size, form and number of leaflets, in the size of the plant, in the serration of the margins, in the degree of roughness of the surface, in every feature in which one walnut may differ from another.
Hybrid Mesembraynthemum.

Some time since, a hybrid mesembryanthemum was developed, and lasted for four years, forming an attractive plant with a profusion of white flowers. Then all individuals, whereever located, died at once, doubtless because conditions were adverse: but there was no visible cause of soil, of insect pest, of fungus or of climate. These plants all died from the root up. A hybrid of petunia and nicotiana has abundance of flowers and a large vigorous leaves, but the roots are inadequate. A hybrid red poppy is formed by uniting the opium poppy with the oriental poppy. These hybrids bloom every day of the year, while the blooming season of either parent is only a few weeks, but they yield no seed. The seed capsules are developed in great variety, some of them four to six times as large as the capsules of either parent. Others are scarcely thicker than the stem which hears them, while others are absolutely and completely absent. This hybrid poppy is tall and generally branches like the opium poppy. It is perennial, although its pistillate or seed ancestor is a short-lived annual. Sample of Hybrid Poppies. This red poppy can even be divided at the root and multiplied like the perennial oriental poppy. These hybrids have generally a dark mark at the base of the scarlet petals as in the oriental poppy; in some the leaves are smoothish and glaucous, as in the opium poppy; in most, deep green and hairy, more as in the other. Many flowers have their stems coalescent with that of the neighboring flower.

"These second generation hybrid poppy plants unexpectedly all proved to be perennials, and are now making a tremendous growth; the clusters of foliage of Sample Leaves of Two Species of Bocconia, showing One of Thousands of Cases of Great Variation in Foliage in Closely Related Species. some of them are fourteen to eighteen inches across already. Among this second generation hybrid lot of poppies each single plant seems to be different from every other plant in the lot and strange to say the leaves now resemble not only poppy leaves, but celandine, various thistles, primroses, turnips, mustards and numerous other plants are very closely imitated, showing most astounding variations."

The striped amaryllis, vittata, hybridized with a Mexican species, formosissima, has narrow twisted petals of a very deep scarlet and nearly plain. The leaves are much narrower than in the vittata, the stalks more slender, and the plants more profuse bloomers.

Hybridizing crinum with amaryllis develops a plant with a fine


Leaves from Hybrid Poppies, showing unusual variations in foliage even for second generation hybrids. Blossoms vary about as much as the leaves—the habits of the plants also. These are an average random selection from about two thousand second generation seedlings.





Capsules of Second Generation Hybrid Poppies, showing series of variations from complete absence of capsules to capsules of unusual size and to double capsules of unusual size. These selected at random from about 2,000 plants. The individual plants which produce these types generally follow them in all the capsules.






flower but no seeds. Crossing the small hardy white calla with a yellow one which is not hardy, develops, with selection, a hardy yellow calla.

A crinum from Florida is hardy but not handsome. Crossing this with a handsome crinum from Mexico, the plants were selected for those which should be both hardy and handsome. The desired qualities of the two species have been combined and other valuable new qualities incidentally developed as regeneration and selection proceeded.

In hybridizing callas, the yellow ones with the white, to form a hardy yellow race, some of the resultant plants have pale flowers, some light yellow, and those chosen are made deep yellow by selection from second and later generations. Both parent plants in this case have leaves blotched with white, and this is found in all the descendants.

Hybridizing the wild flower, Erysimum arkansanum, which is yellow, with a native wild white species, resulted in the first generation a perfect blend of yellow and white; with a second generation the species separate completely, about five per cent, of those examined being yellow, the other ninety-five per cent, white; white dominant. With a hybrid Thalictrum, seed pods are developed more abundantly than with either parent, but the seeds are not viable.

We may expect variations in form, size, color, quality, fragrance, vigor or any other characteristic. To get variation in any one direction is to open the door to anything else. Hybridizing the Japanese quince with the common quince, we have large-leaved seedlings which look quite different from the parent (common quince). The final result is a seedling looking like the Japanese quince, without the power of continued growth (too wide a cross to blend permanently or profitably).

Some of the black raspberries when hybridized with some of the blackberries usually die when the time comes to bear fruit. Many hybrids perish under the stress of reproduction. The Amaryllis vittata is now eight to eleven inches across, being nearly four times as broad as before the work of selection for size was begun, and with vigor and freedom of growth and bloom amazingly increased. On a strip of poor land it grows very small, with narrow leaves and slender flowers, but on the same poor land some of the hybrid variants grow very large and pay no attention to the soil. A variant of Ampelopsis quinquefolia has very large leaves, highly colored in the fall, but no fruit. Mimulus tigrinus of Europe has very many variations. Its flowers are yellow, with patches of orange and other colors. When crossed with some oij our native species, the seedlings are greatly improved in all respects, even in blooming, yet rarely produce seeds.

It is generally much easier to develop variations in seedlings from variegated flowers than from those of solid color (the variegation shows a lack of complete amalgamation). A double mimulus is formed of the hose-en-hose sort. One hybrid poppy produces an abortive flower

Original Wild Stoneless Plum at the Top and 14 of its Seedlings when crossed with the French Prune below, about 1/2 Size.

inside the capsule. All seedlings always vary more or less. With the same parent, one fruit may be two and one half or more times the diameter of the other, of a different color, flavor or differing in almost all respects. "There is no prepotency of male or female as such. Prepotency depends wholly on heredity. We can not rely on the stoneless types being prepotent, but a certain number of trees producing stoneless fruit usually come from crossing them with those having stones. The prepotency to produce a stone, or a half stone, having been more thoroughly fixed by ages of stone-producing trees, will perhaps be about ninety-nine times out of one hundred. But other things being equal, there is absolutely no balance in favor of either sex. This may be set down as fixed."

With plum-almond crosses there is every kind of variation in the flowers. Some have all stamens, some have many petals or none, some never open, and some have pistils only.




The Climax plum is a cross of the bitter, flat, tomato-shaped Chinese plum, Prunus simoni, and the Japanese plum, Prunus triflora. The Chinese plum produces almost no pollen; hardly a grain of it is known, not more than one could put in his eye without feeling it; but the whole fruit shipping industry of the world has been changed by this hybrid plum (Climax) produced by it. With many crosses of many things it is certain that forms of great importance will come out every year, though never in profusion.

Original and Improved Beach Plum.

In developing a spineless cactus for stock-feeding, selections were made from the three hardy northern species, Opuntia rafinesquii, O, mesacantha and O. vulgaris; these were crossed with O. tuna, O. ficusindica and with a Small opuntia from Central America, almost thornless.

The cactus has smooth cotyledons, but the first bud is covered with thorns. These thorns have also been eliminated by selecting the smoothest individual seedlings without crossing. Crossing in this case generally interrupts the process, as it brings out well-fixed ancestral traits, but later, to combine the best qualities of several species, crossing and selection must be resorted to. Examples seen were shoots of the original stock, prickly; the second generation, slightly prickly; the third, without thorns; and later the spicules even within the substance of the cactus have been removed so as to make the cactus very excellent food for cattle. This will have very great value in the arid regions. Some cacti lose the thorns on the plant but retain them on the fruit; others vice versa. By crossing and extensive and intensive selection a cactus may be improved in various ways besides being deprived of thorns and of the internal spicules in six or less generations; these, by means of cuttings, may be multiplied rapidly to any extent, but the process, to be complete, generally takes longer. This thornless cactus should prove of very great value in the development of desert regions as Arizona or Sonora, as the quantity of food produced per acre is enormous.

The Bartlett plum has the flavor of a Bartlett pear, but even more strongly developed. The 'rice seed' plum has extremely small seeds. The stoneless plum is a cross of the French prune with a wild plum having the stone almost eliminated by a fortuitous variation. The result thus far is a great number of stoneless plums of good size, but in flavor inferior to the best cultivated ones. These are being crossed again to improve the flavor, and new selections made.

Crossing the Japan and the New England chestnut (Castanea

Ten Varieties of Plums grown from the Seed of the Burbank Plum crossed with the Apricot Plum, showing Variations.

japonica and C. americana), the trees, leaves, growth and nuts are midway; second generation and later generations as usual show more varied combinations and variations. To breed the burrs off from chestnuts is dangerous, because it allows the birds to get in at the nuts. The



Bed of Seedlings from Spineless Cactus, showing here and there Reversion to the Original Spine Form.



burr is originally intended to keep off the birds. In developing a superior variety of the Persian (often called English) walnut (Juglans regia), the shell was made too thin, so that the birds could break in. It was necessary to make new selections and crossings to thicken the shell and still retain its other superior qualities.

Thallus and Fruit of Spineless Cactus.

The Pierce grape was a bud sport from the Isabella, producing much larger fruit. This bud sport remains constant. All the seedlings even from it are similar to the Pierce grape, following the bud sport (Pierce) and not reverting to the real parent form of the Isabella. Some ripen early, some late; some are pale, and some are black; but all resemble the Pierce more than the Isabella. Cultivating a choke cherry, the seeds all from one parent tree, many variations are found, although the soil in which they are placed is uniform. Among them was found one variant less bitter than The Plumcot—an Absolutely New Fruit. usual; others earlier or later ripening and with larger or smaller fruit or leaves, and an almost bewildering number and variety of other variations. A peach-almond cross often develops a tree as large as ten peach trees or almond trees of the same age. Sometimes a similar cross with different individuals of the same species will produce opposite or totally different results, owing to past heredity, either recent or far back. Crosses are sometimes more vigorous than either parent and more than any descendant, but other cases are just the reverse. The more variant crosses are often less vigorous, and sometimes yield seedlings that can not exist. Sometimes all die in the fruiting season. A peach named 'Quality' is one of the best peaches extant—a cross of the Muir and the Crawford. A cross of the nectrine and peach also produces variant types of value. In some hybrids of petunia and tobacco, the roots fail while the tops may be of unusual vigor. These individuals can only be kept alive for any length of time by grafting, another instance—if other were needed—of the parallelism of crossing and grafting.

"A character may be latent through many generations or centuries, appearing when the right cross brings it out; or it may appear under specially favorable or peculiar conditions of growth."

According to Burbank, "the facts of plant life demand a kinetic theory of evolution, a slight change from Huxley's statement that 'matter is a magazine of force,' to that of matter being force alone. The time will come when the theory of ions will be thrown aside and no line left between force and matter. We can not get the right perspective in science unless we go beyond our senses. A dead material universe moved by outside forces is in itself highly improbable, but a universe of force alone is probable, but requires great effort to make it conceivable, because we must conceive it in the terms of our sense experience."

Popular Science Monthly/Volume 66/January 1905/Some Experiments of Luther Burbank - Wikisource, the free online library

en.wikisource.org

 

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Luther Burbank, at one of his experimental farms in 1901. The World’s Work/Public Domain
Luther Burbank was America’s most legendary horticulturist. At the turn of the 20th century, he developed hundreds of new fruit, vegetable, and flower varieties, creating marvels such as the Shasta daisy and the Santa Rosa plum. If America had a national plant, it might be the his blight-resistant russet Burbank potato, which alleviated the lingering effects of the Irish famine and makes up McDonald’s French fries today.



The media portrayed Burbank as a saintly, botanical wizard. For decades, thousands of people traveled to his Santa Rosa home, trying to catch a glimpse of him at work. Thomas Edison and Henry Ford sought his friendship, and after his death, both Frida Kahlo and Diego Rivera painted him. Around his grave at the Luther Burbank Home and Gardens, the plants he pioneered are still growing, watched over by garden curator Rachel Spaeth.

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During Burbank’s life, his home became a tourist attraction. Brück & Sohn Kunstverlag Meißen/Public Domain
Despite all the press and acclaim, much of Burbank’s work remains mysterious—a problem that Spaeth, who has worked at the Burbank Home for a decade, has set out to solve. Once Burbank died, much of his knowledge was lost. Burbank was a terrible notetaker and an untrained scientist; he rarely recorded his process of creation as he developed plants that were sold through nurseries and seed catalogues. He also had good reason not to advertise the genetic makeup of his plants: In the early 20th century, there was no way to patent them.


“A man can patent a mousetrap or copyright a nasty song,” Burbank once groused. “But if he gives to the world a new fruit that will add millions to the value of earth’s annual harvests, he will be fortunate if he is rewarded by so much as having his name connected with the result.”

This created a challenge that Spaeth is facing. By sorting through what Burbank left behind, Spaeth hopes to uncover the lost parentage of his plums, the fruit which Burbank worked with more than any other.

Rachel Spaeth, the Luther Burbank Home and Garden’s curator. Courtesy of the Luther Burbank Home and Gardens
For a botanist and biologist such as Spaeth, it’s more necessary than ever to decipher Burbank’s work. In the event of plant disease or a changing climate, knowing the parents of popular varietals could help future horticulturists develop heartier new varieties. “It’s a big part of food security,” she says. She’s long admired Burbank, once strolling through his gardens every day on her way to work. But also, she tells me, there’s an undeniable impulse to continue Burbank’s work, with the same genetic material he used. She hopes to develop new plums, and even examine more of Burbank’s plants outside of the fruit. The Burbank gardens are still packed with his experiments, many of them genetic anomalies.


As garden curator, Spaeth is uniquely situated for research on Burbank. Their backgrounds even have some similarities. As children, they both grew up in the East: She in rural Pennsylvania, he in Massachusetts. Both were influenced by their families’ gardens. Part of living where she did, Spaeth tells me, meant a diet of mostly homegrown fruits and vegetables.

The Santa Rosa plum, another one of Burbank’s developments. Courtesy of the Luther Burbank Home and Gardens
Both relocated out of necessity. He sold the the russet potato to a seed company for $150 dollars while he still lived in Massachusetts. With the money, he left for California, settling down in Santa Rosa. Spaeth left too, moving to California in search of “better weather and cheaper education.” But while Burbank only received a high school education, Spaeth’s plum project is part of her PhD research at nearby University of California, Davis.

Spaeth’s first challenge is to gather Burbank’s 250 plum varieties. With a living database of Burbank’s plums growing at the Burbank Home, it will be much easier to pick out family connections, she says. But many have been scattered to the winds. Nurseries and private growers have various varieties, and she’s collected samples of those. Other times, she turns to the local Santa Rosa community, going on the radio to appeal to locals who might have 100-year-old plum trees. Nearly every time, she’s been successful in finding a named Burbank variety. That might not be as strange as expected. Fruit trees flourish in Santa Rosa. Burbank himself called the region “God’s gift to fruit growers.”

The greenhouse at the Burbank Home houses many of the horticulturist’s plants. Courtesy of the Luther Burbank Home and Gardens
Yet some of Burbank’s plum and plum hybrids have never been named. At the Burbank House, one of Burbank’s orphaned plumcots is still growing. “The apricot was the pollen parent, and the plum was the mother tree,” says Spaeth. Burbank was the first to cross apricots and plums. “He wasn’t bound by scientific principles,” Speath says. When told the two fruits were too distantly related to cross, Burbank’s response was, as Spaeth sums it up, “Watch me!”

The flesh of the plumcot is chartreuse green, and the exterior is a dark bluish purple. “It’s the only tree of its kind,” Spaeth says. Once she has a clearer idea of the mystery plumcot’s genealogy, the Burbank Home will name it.

Typically, horticulturists use brushes to apply pollen from one parent tree to the blossoms of another. The bloom’s stamen (the male sexual part) is cut off to keep it from pollinating itself. The branch is bagged to prevent lothario bees from coming and administering unintended pollen. Then, a new fruit develops.


There’s a sticky problem there, too. It’s difficult to trace Burbank’s parent trees because he didn’t bag his blossoms, and marked trees with scraps of his own clothing instead of signage. In contrast, other horticulturists took detailed notes. But Burbank was more artist than scientist, and he only had a high school education. His unorthodox methods often frustrated his contemporaries. His work, then, is “very difficult to reproduce,” Spaeth says.

One of Burbank’s prints, for an “Odd” plumcot. Courtesy of the Luther Burbank Home and Gardens
That’s where genetics come in. The second step of Spaeth’s research is getting her hands on more of Burbank’s notes. Burbank did keep some records: He traced the shapes of his fruits and squashed them onto paper to make impressions. At the moment, the majority of those prints are at the Library of Congress. With the genetic material left over on the prints, Sparth can extract the genome and compare it to the living plums in her growing collection. She compares the process to how archeologists test the DNA of mummies, with a “forensic version of genomics.” She expects that time will have degraded what genome she can extract from the fruit prints, making the Burbank Home’s living collection even more vital, “to fill in some of those holes.”

Spaeth is still in the early stages, and she hasn’t identified any plum parents yet. But when she does, she plans on crossing his varieties to recreate Burbank’s methods—and his plums. She expects some trial and error: After all, “you’re dealing with random assortment, genetics, and just how biology works in general,” she says. The same parents don’t necessarily mean the same fruits, as anyone with siblings knows.

A plum tree in bloom at the Burbank Home. Courtesy of the Luther Burbank Home and Gardens
At the moment, Spaeth is making her own fruit prints to see what kind of data can be extracted. When she has results, she plans on requesting Burbank’s prints from the Library of Congress. It’s not a request to make lightly: She’ll have to peel the residues off the vintage prints to analyze them. But the Library often opens its archives to valuable research, so she thinks they’ll be amenable.

Burbank, while a genius, wasn’t an eccentric. His fears about having his work stolen were well-founded. Since plants couldn’t be patented, he depended on his creations for income. His death and the loss of his knowledge led Congress to allow the patenting of plants. Thomas Edison hoped that the decision would lead to many new Burbanks, who could provide the world with a wealth of new plants. But while Spaeth might be one of them, she also takes her cues from a different treasure-seeker. “Sometimes I feel like the Indiana Jones of the plant world,” she jokes.

 

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Plant breeding basics​

The process of artificial plant selection is made up of two main parts: pollination and screening of offspring. Pollination includes intentionally transferring pollen from one plant to another to create an offspring. This part of the process is also called “crossing.” Sometimes it is important to know which plant is the pollen donor so both parents are controlled. In other cases, the plant is open pollinated, which means the pollen donor is anonymous, but comes from a population that was in close enough proximity to the seed-bearing plant. If this process successfully creates seeds, then offspring must be evaluated for desirable traits. Offspring that do not meet the desired criteria are discarded from the breeding population. Burbank would often save just a handful of offspring and burn the rest to remove them from his breeding populations.
The direct result of a cross between two parents is called an F1 hybrid. Some F1 hybrids have valuable traits and are directly offered for sale. These traits are collectively called a phenotype. Many sunflower, cucumber, corn, and tomato plants on the market today are F1 hybrids. They are bred annually using the exact same parental cross every time; a crop of sunflowers grown this year will be for sale in next year’s seed packet. If you tried to save the seeds from these plants to grow them the following year, they will not produce the same phenotypes you found desirable the previous season. This is because parents were intentionally crossed for the phenotype found in the F1 hybrid. When the F1 generation crosses with itself, the subsequent F2 hybrid will have attributes that are more like one of the original parents.
In some cases, an F1 hybrid has undesirable characteristics. For example, if you’ve ever grown a pumpkin and a zucchini too close together and tried to save seeds from them to plant the following year, you inadvertently created an open-pollinated F1 hybrid—an unintentional cross between the pumpkin and zucchini. That F1 hybrid in this case is the dreaded “pumpkini,” a hard, inedible log of a fruit that is neither pumpkin nor zucchini, but rather a mix of both. Knowing whether a plant will hybridize on its own in your space is incredibly important for saving seeds and driving artificial selection.

Burbank pumpkin seeds. Credit: University of Wisconsin Libraries

The more genetically distant the parents of a cross are, the wider the range of variation in the generations that follow. The more similar the parents are, the less variation in the offspring. Most plants can be bred within the same species. This is also known as intraspecific hybridization. This would be like shuffling two different brands of playing cards together. There will be some small changes in appearance, but overall, the play of the game is the same. Burbank primarily experimented with interspecific hybridization, crossing two completely different species within the same genus. Think of it as shuffling a deck of playing cards with a deck of uno cards. This kind of hybridization is not as successful at creating offspring, but when offspring are generated, it is more successful at introducing novel characteristics. One interspecific hybrid you may be familiar with is the plumcot. Burbank claimed to have crossed a plum and an apricot and was largely rejected by the scientific community due to his lack of documentation. It wasn’t until forty years after his death when Floyd Zaiger also made the cross that Burbank’s work was taken seriously. Now you can purchase and enjoy plumcots, pluots, apriums, pluerries, and nectaplums distributed through many retail grocery stores.

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"Less than one in a thousand are worth saving" ? @Sam_Skunkman

 

[acespicoli]

Found this during my ox gold strain research, reason why many farmers plant this crop can make a modest tract of land profitable and poverty is a harsh reality of survival

 

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We hope that this new preservation work that we present to the cannabis community will please our loyal fans (who for a decade have been asking us to offer a good pure Thai again), as well as lovers of traditional pure sativas and the most purists among preservationists.

Thai Regular - aceseeds

SOUTHEAST ASIAN LANDRACE SATIVA PAR EXCELLENCE

www.aceseeds.org

Flower 90-120 days
@dubi got some stuff for the #ICmagfam
Added to the collection

 

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Chapter 10
Selective Breeding for Cannabis Variety

https://www.researchgate.net/publication/361541995_Selective_Breeding_for_Cannabis_Variety

Shanmugam Aravindan, Mohanapriya Balamurugan,
Manivelan Kalaiarasan, and Pushpa Raman

Abstract Cannabis is the most versatile species. Hemp and marijuana have been
used for fibre, oil, medicinal and recreational purposes from millennia. Throughout
the last century, the plant has been generally outlawed because of its psychotropic
effects in many nations. In recent past, the studies on cannabis revealed the evidence
of its high medicinal properties and its uses in treating life threatening diseases,
which leads to the relaxation of legislation in many counties. Now, the genetic and
genomics as well as the cannabis derived products enjoys renewed attention. In this
chapter, the discussion was made on the advent of genomics and breeding strategies
to improve various traits of cannabis. This will bring insights on future direction of
cannabis breeding.
Keywords Cannabis · Breeding · Hemp · Sex-determination · Flowering · Cannabinoid
10.1 Introduction

Cannabis species gained great attention today because of its numerous uses in medic-
inal, industrial and recreational purposes (Backer et al. 2020; Kovalchuk et al. 2020;

Russo 2019). The plant is cultivated mainly for its fibre, seed and cannabinoids.
It constitutes about 500 phytochemicals with various therapeutic uses to treat life
threatening diseases, most notably Parkinson’s disease, multiple sclerosis, epilepsy,
Alzheimer’s disease, cancer and diabetes (Erzen et al. 2021; Gibbard et al. 2021;
A. Shanmugam · B. Mohanapriya
Department of Genetics and Plant Breeding, Tamil Nadu Agricultural University, Coimbatore,
India
K. Manivelan
Department of Genetics and Plant Breeding, Agricultural College and Research Institute,
Madurai, India
R. Pushpa (B)
Tamil Nadu Rice Research Institute, Aduthurai, India
e-mail: [email protected]
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2022
T. Belwal and N. C. Belwal (eds.), Revolutionizing the Potential of Hemp and Its
Products in Changing the Global Economy,

https://doi.org/10.1007/978-3-031-05144-9_10

181

182 A. Shanmugam et al.
Murnion 2015; Namdar et al. 2018). In cannabis, the major psychoactive component
is THC (tetrahydrocannabinol), the THC content of 0.3% or less is considered as the
non-psychoactive and grown for hemp (fibre type) and in contrast, marijuana (drug
type) contains up to 30% of THC (Barcaccia et al. 2020; Clarke and Watson 2007;
Mudge et al. 2019). Apart, hemp varieties have great potential to sequestrate carbon
due to its rapid growth. Hence, it can be utilized as biofuel or as carbon repository
in construction materials (Finnan and Styles 2013). Beyond that, hemp seed oil also
has high nutrition value as it the rich reserve of omega-6 and omega-3 PUFA (3:1)

(Leizer et al. 2000; Schultz et al. 2020). Despite, marijuana cultivation is criminal-
ized and prohibited around globe because of its psychoactive essence of THC. The

“United Nation convention against Illicit Traffic in Narcotic Drugs and Psychotropic
Substances of 1988” recognized cannabis as the narcotic drug and prohibited its use
and cultivation, still it posing the major issue in legitimization of cannabis with high
THC content (Aguilar et al. 2018). At present, the studies over the decades revealed
the potential of cannabis on treating various diseases. Thus, many countries slowly
releasing their legalization on cannabis grown for medicinal and scientific objectives
in regulated region. This opens up the avenue to study the genetic and genomics of
cannabis and paves way for the breeding of new varieties of this versatile for various
purposes. Thus, the comprehensive review was made in this chapter on its botanical
classification, advent of genomics and breeding strategies to improve various traits
of cannabis.

10.2 Botany of Cannabis
Cannabis (2n = 2x = 20) is a dioecious plant originated in central Asia
about 5000 BC and distributed around Asia and Africa (Table 10.1). The genus
cannabis comprises majorly of three species viz., (a) C. sativa (hemp type) (b) C.
Table 10.1 The current
scientific classification of
Cannabis

Taxon Scientific name and common name
Kingdom Plantae (plants)
Subkingdom Tracheobionta
Superdivision Spermatophyta
Division Magnoliophyta
Class Equisetopsida
Subclass Magnoliidae
Order Rosales
Family Cannabaceae
Genus Cannabis
Species Cannabis sativa L.
Source USDA-ARS 2020

10 Selective Breeding for Cannabis Variety 183
indica (drug-type) contains remarkable amount of the psychoactive compound 9-
tetrahydrocannabinol (9-THC) and (c) C. ruderalis (intermediate). C. sativa is an

annual with erect stems and robust taproot. The stems are woody, branched (oppo-
site or alternate), furrowed and angular in shape and height varies from 1 to 6 m.

They have a strong taproot system, usually goes upto 30–60 cm depth but 2.5 m in

loose soils and shows more branching in wet soils. Leaves are arranged in the orien-
tation of either alternate, opposite or spiral, green in color with seven lobes and have

serrated margins. Nevertheless, the shape and size of the leaflets alters in accordance
to their origin. The leaflets have the length of 6–11 cm and breadth of 2–15 mm.
The both upper and lower surfaces have dispersed resinous trichomes. Inflorescences
contains several flower heads found on leafy stems from each leaf axil. The staminate
flowers (2.5–4 mm) possess five pale-green sepals and pendant stamens with lanky
filaments. The sessile pistillate flower are found in pairs (Fig. 10.1). The type of fruit
is achene (single seed) have hard shell securely covers with ovary’s thin wall. It is
about 2–5 mm long, ellipsoid in shape, bit compressed, smooth, widely have brown
colour and mottled.

(a) (b)

(c)

(d)

Fig. 10.1 a Female flower of cannabis. b Part of the pistillate flower. c Female flower. d Male
flower (Source Farag and Kayser 2017)

184 A. Shanmugam et al.
10.3 Breeding of Cannabis
Traditionally cannabis breeding is based on “mass selection”, “cross-breeding”,
“inbreeding” and “hybrid breeding”. For decades, both medicinal (drug type) and
hemp (fibre type) varieties were produced by mass selection. For traits with a high
heritability, mass selection is being used. Effortlessly, Cannabis cultivars can be
multiplied and maintained through vegetative propagation. Cannabis is usually a

dioecious crop pollinated by wind. Thus, the genetic structure of both natural popu-
lation and mass selected breeds shows high heterogeneity, whilst this high genetic

diversity favoured selective breeding. Inbreeding can also be possibly achieved by
producing monoecious plants artificially i.e., by alter the flowers sex from pistillate
to staminate on few branches to promote autogamy. Several efforts were made to
induce monoeciousness using chemicals have revolutionized the cannabis breeding.

Nevertheless, sexual reproduction shows genetic instability and phenotypic vari-
ability, the optimistic way to use cannabis seed varieties are the development of

true F1 hybrids. At present, numerous hybrids and some pure lines were brought
into commercial cultivation by many private sectors (Table 10.2). Heterosis can be
exploited in present-day fibre (hemp) varieties, but it has yet to be investigated or
documented in recreation (drug) types. The first publication on the genome sequence
of C. sativa in 2011 aided the transition from conventional breeding to molecular
approaches (Van Bakel et al. 2011). Thus, the advent of genomics and in silico tools
will create a new avenue for targeted cannabis breeding (Fig. 10.2).

10.3.1 Breeding for Fibre Quality

Fibre quality depends strongly on fibre bundles morphology and cell wall chem-
ical composition of the elementary fibre (Rowell 2000). The fibre quality and yield

changes over a period during plant development viz., cellulose content rises up to
56–65% till late flowering. Besides, the fibre quality is affected by various factors
like cultural practices such as density of plants, application of nitrogen fertilizer and

time of harvest (Amaducci et al. 2008b). High quality fibre and suitable for mechan-
ical extraction are the important traits appreciated by the hemp industry. High quality

trait includes high and fine bast fibre, high cellulose, lower degree of lignification,
minimized cross links between pectin and other structural cell wall components and
efficient decortication properties (Ranalli 2004). However, the relationship between
lignin content and fibre quality relies on its purpose. In concise, lower level of lignin is
preferable for textile purpose, because lignin polymer impede decortication process

and intensifies the rigidity of fibres (Ranalli 2004). Contrarily, antioxidant and adhe-
sion properties of lignin are related to increase in composites stability and encourage

the attention of lignified fibres in novel application (Pickering et al. 2016). Recently,
an association panel with 123 hemp cultivars from varied parts around the globe
were reported with the extensive phenotypic variations for 28 traits associated with

10 Selective Breeding for Cannabis Variety 185
Table 10.2 Origin of Cannabis varieties
Variety Country
Finola Finland
Glukhov 33, Kuban, USO 11, Zenica, USO 13, USO 15, USO 31,
YUSO 14, YUSO 16

Ukraine
Asso, Carmagnola, CS (Carmagnola Selezionata), Carmono, Carma,
Codimono, Eletta Campana, Ferrara, Ermes, Fibrimor
Fibranova

Italy
Fasamo, Ferimon Germany
Santhica 27, Epsilon 68, Fedora 17, Fedora 19, Fedrina 74, Felina 32,
Felina 34, Fibrimon 21, Fibrimon 24, Fibrimon 56, Futura, Futura 77,
Futura 75, Santhica 23, Dioica 88

France

Kompolti Sargaszaru, Kinai unisexualis, Kompolti, Kompolti Hybrid
TC, Kompolti Hyper, Elite, Fibriko

Hungary
Fibramulta 151, Irene, Lovrin 110, Moldovan, Secuieni 1 Romania
Beniko, Bialobrzeskie, LKCSD, Dolnoslaskie Poland
Chamaeleon, Dutch “Yellow” line Netherlands
Ermakovskaya Mestnaya Russia
Delta 405, Delta-llosa Spain
Kenvir Turkey
Swissmix Swiss
Ratslaviska Czech
Silistrensi, Mecnaja copt Bulgaria
Pesnica Slovenia
Flajsmanova, Novosadksa, Novosadska plus, Novosadska konoplja Former Yugoslavia
Kinai Egylaki, Kinai Ketlaki China
Kozuhura Zairai Japan
Source Farag and Kayser 2017
fibre quality (Petit et al. 2020c). The content of cellulose, hemicellulose, lignin and
bast fibre were determined largely by the genetic components with high heritability
and low G × E interactions, suggesting that this panel is promising for maximizing
the genetic gain and further studies of genetics underlying the fibre quality traits. On
contrary, the variability in pectin, bast fibre fineness and decortication efficiency are
highly influenced by environment. Despite the large variability, the genetic means of
these traits remains mysterious. Salentijn et al. (2019) reviewed the candidate genes
for quality fibre traits and majority of them are involved in lignin metabolism or
encode for plant hormones engaged in development with a feasible impact on lignin.
More recently (Petit et al. 2020b) used the same panel for genome-wide association
(GWAS) approach and genotyped using a large set (>600,000) of SNPs to unravel the
quantitative trait loci (QTLs) linked with quality fibre. In this study, 16 QTLs among
six were stable over environments were identified for various fibre quality traits like

186 A. Shanmugam et al.

Fig. 10.2 Traits targeted in cannabis improvement
mannose, glucose, xylose, lignin, glucuronic acid, and bast fibre content. In addition,
12 candidate genes are reported to have a function in biogenesis and alteration of
lignin, mono and polysaccharides. Still, breeding for this trait is bounded, largely
due to the inadequate understanding on its genetic architecture.

10.3.2 Breeding for Flowering Behaviour and Sex
Determination
Cannabis is extremely influenced by photoperiod and temperature, the short-day
condition with uninterrupted darkness of ∼10–12 h is given which induces the
flowering instantaneously (Amaducci et al. 2008a; Salentijn et al. 2019)). However,
cannabis cultivated in 24 h light also flowered, but dry matter content in the floral

parts are largely reduced (Schaffner 1926). A few cannabis cultivars grown predomi-
nantly for cannabinoid production are day-neutral plants viz.,C. sativa var. spontanea

(McPartland 2018). On the basis of flowering time, the genotypes can be categorized
into early (40–60 days); medium (60–90 days) and late (90–120 days) types (Zatta
et al. 2012). In diecious cannabis, Sex determination system has been understood
well. Males possess the heterogametic chromosome (XY) whereas feminine plants
have homogametic sex (XX). Diecious plants occurs extensively in nature, whereas

10 Selective Breeding for Cannabis Variety 187

monecious species are the result of mutants selected in the course of domestica-
tion. Monecious plants usually have diverse sex ratios may gradually turn back to

natural dioecy after few generations (Faux and Bertin 2014). Therefore, to conserve
monoeciousness careful regular selection for monecious phenotypes are required at
the time of seed multiplication (Mediavilla et al. 2001). The quantitative variation

and inconsistency of the phenotype over generations proposed that the sex expres-
sion is quiet polygenic in nature (Faux and Bertin 2014). Besides the genetic control,

sex determination is also regulated by epigenetic factors (Soldatova and Khryanin
2010). Apart from that, ions and phytohormones also alters the sex expression. Zeatin
promotes femaleness by accumulating copper (Cu++) and zinc (Zn++) ions, on the
other hand Pb++ ions favours masculinity effect (Galoch 1978). Generally, auxins
and ethylene induce female flower, whereas cytokinins and gibberellins induce male
flowers. The use of chemicals such as silver thiosulfate also induce masculine effect

on female (XX) plants and is widely used in seed production (Kaushal 2012). Flow-
ering time and sex determination have strong influence on fibre quality and seed

yield of cannabis. The progression from juvenile to the reproductive phases is most
crucial in hemp breeding, because maximal quality fibre occurs immediately after
flowering (Amaducci et al. 2008b). Later, the fibre quality declines as the transit
of allocated nutrition and carbon from vegetative parts towards developing floral
parts and seeds. In addition, the flowering synchronizes with the phase of secondary
bast fibre production, is marked by profound lignification and may results in poor
fibre quality (Liu et al. 2015). Another crucial factor directing those traits is plant
sex. Large difference in the fibre quality and seed yield was observed between the
monecious and diecious cultivars. Recently, a study reported that monecious breeds

contains more average bast fibres with elevated cellulose and mannan level, never-
theless diecious genotypes are late flowering with higher xylans and lignin content

(Petit et al. 2020c). The lignification gets intense on the commencement of flow-
ering and proceeds till seed maturation. Male plants are less lignified and develop

fine fibres in compared to female, but they are highly susceptible to pest (Amaducci
et al. 2015; Liu et al. 2015). Moreover, the higher proportion of males resulted in
the reduction of seed output (Faux and Bertin 2014). The targeted breeding for the

regulation of blooming time and sex expression or determination offers the possi-
bility for long term gains in seed yield and fibres quality. Attempts were made to

map the sex-linked marker and QTLs associated with the sex expression (Faux et al.
2016). An hemp association panel with 123 genotypes was found to have a wide
variation in blooming time and sex determination traits (Petit et al. 2020c). This
study shows that the traits have high heritability and are controlled by the genetic
elements. Additionally, significant GxE interactions were observed for the flowering
time. Genome-Wide Association Studies (GWAS) was on performed on same 123
accession panel using 600 k SNP markers. Across the environment, eight QTLS
among six for blooming time attributes and two for sex determination covering the

genic regions of 33 predicted transcripts involving microRNA, miR156 were iden-
tified. In flowering time QTLs, the gene involved in perception and transduction of

lights and transcription factors that regulates flowering were reported whereas in
QTLs for sex determination, the phytohormones especially auxins and gibberellic

188 A. Shanmugam et al.

acid were discovered (Petit et al. 2020a). However, knowledge on genetic and molec-
ular basis on sex determination, sexual dimorphism and blooming time is limited.

The markers associated with the selection for monoecy or specific flowering time
phenotypes are still in its infancy.

10.3.3 Breeding for Cannabinoid Content
For the past two decades, the genetics means of the various chemotypes has been well
studied. However, the complexity of Cannabis genome with numerous transposable
elements and large heterozygosity made it more challenging to derive conclusive
results on loci controlling cannabinoid production (Laverty et al. 2019). Distinct loci
had been hypothesized for determining plant chemotypes. The locus B possesses two
codominant allele, “BT codes for the THCA/THC synthase, BD for the CBDA/CBA
synthase” (De Meijer et al. 2003). Based on the existence of one or both alleles,
they are classified as chemotype I (BT/BT), chemotype II (BT/BD) or chemotype III
(BD/BD). In addition, null alleles (B0) of synthase gene were proposed to be linked
to chemotype IV where no production of CBDA and THCA thus, the metabolic
precursor cannabigerol (CBGA/CBG) accumulates. Further, two independent locus
O and C encoding for CBCA/CBC synthase is associated with chemotype V and
VI, respectively (Fig. 10.3) (Table 10.3). The chemotype I (high THC) was crossed
with chemotype III (low THC) to study the genetic basis. The resulted F1 plants are
primarily of type II, yields THCA as well as CBDA. In F2, it follows the Mendelian
segregation pattern 1:2:1 ratio of chemotype I, II and III plants respectively (De
Meijer et al. 2003; Weiblen et al. 2015). Accordingly, the results support the concept
of codominant alleles at single locus and evident that these traits are further complex.
The new draft genome analysis postulated that THC and CBD synthases are not coded
by the alleles in same gene, instead rather by the different locus in drug and fibre
type cannabis respectively (Grassa et al. 2018; Laverty et al. 2019). The CBD and
THC synthase genes are embedded between the multiplex tandem duplications of
non-functional synthase genes and interspersed with long terminal repeat (LTR) at
regular intervals which limits the genome assembly and analysis at these loci (Grassa
et al. 2018; Laverty et al. 2019). In addition, copy number variation in CBD and THC
synthase genes may also influenced the level and constituents of cannabinoid (Vergara
et al. 2019). High throughput analysis of BT and BD markers shows that numerous
plants in fact have both locus (Toth et al. 2020). In addition, numerous plants with
BD/BD genotypes, particularly those produce high CBD, have THCA content above
0.3%, despite the lack of function of BT allele (Toth et al. 2020). This remnant THC
was a by-product of the CBD synthase. The CBDA synthase encodes for both CBDA
and THCA in a 20:1 ratio, according to reports from in vitro studies (Zirpel et al.
2018) and also, in In planta, the similar ratios was observed with high CBD hemp
cultivars (Toth et al., 2020). This shows that increase in CBDA production will also
increase the THCA as a by-product. Then, the Cannabis genotypes with higher level
of CBD might be at the risk of surpassing the legal thresholds limit of THC. Gaining

10 Selective Breeding for Cannabis Variety 189

Fig. 10.3 Biosynthesis pathway of tetrahydrocannabinol (THC) and cannabidiol (CBD)
Table 10.3 Different chemotypes of Cannabis
Chemotype Content (dry weight basis) Locus References
Chemotype I THC prevalent (Drug type)
THC >0.3%; CBD <0.5%

B locus (BT and BT) De Meijer et al.
(2003)

Chemotype II Intermediated
THC ≥0.3%; CBD >0.5%

B locus (BT and BD) De Meijer et al.
(2003)

Cemotype III CBD prevalent (Fibre type)
THC <0.3%; CBD >0.5%

B locus (BD and BD) De Meijer et al.
(2003)

Chemotype IV Cannabigerol (CBG)
prevalent
CBG >0.3%; CBD <0.5%

B0 allele, a mutant form
of the BD locus

De Meijer and
Hammond (2005)

Chemotype V Zero cannabinoids
Total cannabinoids content
<0.2%

Locus (O) located
upstream of the B locus

De Meijer et al.
(2009)

Chemotype VI Prolonged juvenile
chemotype
cannabichromene (CBC)

C De Meijer et al.
(2009)

190 A. Shanmugam et al.
knowledge on the genetics underneath the various chemotypes will be potent for
the targeted breeding programme in future. Strict legal regulations around the globe,
made it hard for the farmers to cultivate chemotype III, IV and V cultivars due to
their residual THCA which arises legislative difficulties. In particular, type III often
has slightly high THC content than the permissible limit (Schilling et al. 2020; Toth
et al. 2020). Thus, the most significant goal of the breeder is to develop zero-THC
lines with high CBD content of about 15–20%. The point mutation may alters the
levels of derivatives (Zirpel et al. 2018). Hence, natural variation prevails for the
CBDA synthase gene associated with altered cannabinoid composition i.e., very low
or lack of THC has to be identified. Other cannabinoids like CBG, CBC and terpenes
variants are highly gaining attention in medical fields (Booth and Bohlmann 2019).
Hence developing cultivars with specified cannabinoid profiles might be a fortune
interest of researcher.

10.3.4 Breeding for Stress Tolerance
The effect of biotic and abiotic stress on crop depends on the crop stage, degree and
duration of stress. The disease affecting the cannabis are “damping off”, “fusarium
and crown rot”, “pythium rot”, “powdery mildew”, “bud rot” and “post-harvest mold”
(Punja 2021). The corn earworm is the key pest of cannabis in particular it damages
the flower bud. Other pest viz., Eurasian hemp borer and Hemp russet mite also

had the greater potential to cause crop injury (Cranshaw et al. 2019). The cannabi-
noid levels are not only involves genetic components and also influenced by various

factors. The exposure of hemp plants to insects spikes up the cannabinoid produc-
tion and exceeds the legal limit of THC. Moreover, feeding of CBD and THC spiked

plants to corn earworm found to have significant reduction of body weight (Jackson
et al. 2021). Among the diseases, powdery mildew has been common for both hemp
and drug type cannabis. The economic loss caused by powdery mildew in cannabis
production is unknown. This will not cause the total crop loss but affects the end use

quality. The use of fungicide to control powdery mildew accommodates with contro-
versies in regard to its efficacy and consumer response (Scott and Punja 2021). Other

management strategies like usage of strong UV lights (Scott and Punja 2021) and
growth-promoting rhizobacteria (Lyu et al. 2019) are also limited, because it yet
becomes most prominent disease in both field and green house condition. Thus, the
genetic resistance will provide greater potential for the growth and sustainability
of cannabis industry. The genetics of Powdery mildew resistance was depends on
the R-genes, present in various crops (Ning et al. 2014). The resistance mechanism
against powdery mildew is complex which involves abundant alterations in gene
expression and production of various biochemical substances (Qiu et al. 2015).The
sequencing and annotation of 42 Cannabis genomes was done and identified copy
number variations (CNVs) and SNPs governing cannabinoid synthesis and powdery
mildew resistance and found that 82 genes were associated with powdery mildew
resistance (McKernan et al. 2020). He also reported that breeding cultivars less

10 Selective Breeding for Cannabis Variety 191
than 0.3% THC might ameliorate pathogen susceptibility. More recently, linkage
mapping with 10 k SNPs identified first “powdery mildew” resistant gene PM1
in the cannabis sativa which is the single-dominant locus endows total resistance
to powdery mildew (Mihalyov and Garfinkel 2021). The research investigating the

stress tolerance of hemp is limited. The transcriptome study revealed the genes differ-
entially expressed between the drought tolerant and susceptible cultivars. The most

notable candidates are NAC, peroxidases, inositol oxygenase, expansin and genes
involved in ABA signaling pathways contribute to the drought tolerance in hemp
(Gao et al. 2018). Additionally, Caplan et al. (2019) reported that under controlled
drought stress condition the concentration of major compounds viz., CBDA, THC
and CBD were increased. However, the duration and timing of the drought stress
is the major manipulating factor. Likewise, the differential expression of proteins
(Cheng et al. 2016) and genes (Cao et al. 2021; Guerriero et al. 2017) in response to
salinity tolerance has also been reported. Hence, further detailed studies are required
to understand the interaction of cannabinoid with various stresses.

10.4 Genomics of Cannabis
The Cannabis is diploid (2n = 20) posses 9 somatic chromosome and a pair of
allosomes. The size of haploid male (XY) genome is reported as 843 Mb and 818 Mb
for female (XX), the presence of largest Y chromosome causes the difference among
sex in their genome size (Sakamoto et al. 1998). In addition, it is predicted that ~
70% of the Cannabis genome accounts for repetitive sequences (Gao et al.2020).
The multiple repeats misassemble in one contig creates assembly collapse. This is
the challenging feature while using short read sequencing technology. In 2011, the
first draft Cannabis genome of drug type cultivar, Purple Kush (PK) was sequenced
using short read sequencing technology, which does not resolved the repeat rich and
low complexity region of the genome (Van Bakel et al. 2011). Recently, long-read or
third generation sequencing, concurrent with linkage and physical mapping allowed
genome assembly at chromosome-level from Finola (FN), CBDRx, PK and wild
Cannabis (CR) cultivar (Gao et al. 2020; Grassa et al. 2018). Sequencing with the
Oxford Nanopore technology, the female genome of CBDRx genotype results in
the assembly size of 876.148 Mb (Grassa et al. 2018). And the first genome-wide
annotation was made and displayed it as a reference genome (Jenkins and Orsburn
2019). Using PacBio single-molecule sequencing, the genomes of PK (female), FN
(male) and CR genomes are sequenced and assembled, have their sizes of about
891.96 Mb, 1009.67 Mb and 812.52 Mb, respectively (Gao et al. 2020; Laverty et al.
2019). The genetic maps were constructed for genomes of CBDRx, PK and FN
varieties (Grassa et al. 2018; Laverty et al. 2019) and physical map for CR genome
(Gao et al. 2020). Moreover, sequence of 40 diverse genotypes were generated with
Illumina as a part of “Cannabis Pan-Genome Project” (McKernan et al. 2020). This
genomic information will serve as a valuable reservoir for understanding the genetics
underlying the extensive phenotypic diversity resides across Cannabis. In addition,

192 A. Shanmugam et al.
bisulfite sequencing, genotyping by sequencing (GBS) and amplicon sequencing are
available for both hemp and drug type cultivars. Based on GBS data representing
400 samples, shows that hemp and drug type cannabis form different populations,
segregating not only at BT or BD locus, but at the locus throughout the genome (Lynch
et al. 2016; Sawler et al. 2015; Soorni et al. 2017). The Bisulfite sequencing discloses
methylation in DNA which takes to the next level perception on gene regulation by
epigenetic mechanisms (Li et al. 2020; Schilling et al. 2020). The characters like sex
expression and flowering time are strongly influenced by environment, and it will help
to investigate on which extent they are epigenetically regulated. This might create
the pavement for ‘climate resilient’ breeding of cannabis. Further, several studies
have been focused on transcriptomics of cannabis. Most notably, the transcriptome
profiling on the bast fibre formation (Behr et al. 2016) and transcriptome sequencing
of trichomes, for the purpose of depicting the expression of genes encoding for
terpene and cannabinoid biogenesis (Livingston et al. 2020; Zager et al. 2019). In
addition, the expression of sex-linked genes has been studied in two recent research.
(McKernan et al. 2020; Prentout et al. 2020). Thus, the abundant data are available on
the genome structure and it will pave way for the breeding advancement in cannabis.

10.5 Constrains in Cannabis Breeding
A “consultative group on international agricultural research (CGIAR)” has facilitated
the easy exchange of knowledge and materials of numerous crops among research
communities which helps in germplasm utilization, but by this the cannabis crop is
not benefited. Genetic diversity is prime most important for any successful breeding
program. But the germplasm diversity in cannabis is under recession due to the legal
prohibition on cultivation and exchange of seeds, replacement of landraces across
the world which forbids ex-situ conservation, preference of clonal propagation and
limited seed viability. The public acceptance of cannabis for medicinal purpose is
established in very few countries but only in indoors cultivation which also leads to
narrow gene pool. Preservation of diversity requires seed banks not only just seed
companies, sustained funding and research efforts.

10.6 Conclusion and Future Prospects
In debates, the cannabis crop has always heated up the controversy from ethics
to scientific pharmacological and therapeutic applications and even in taxonomical
classification. Apart, the studies over the years have witnessed the significant progress
in cannabis research and unraveled the exciting opportunities and challenges forward.
The manipulation of cannabinoid synthases as well as the genetic and environmental
control of flowering and sex determination has been ratified as the complex field
of research in cannabis. The major challenge in cannabis breeding is developing

10 Selective Breeding for Cannabis Variety 193
crop ideotypes that harmonize all traits, currently it is not possible thus the genetic
control of the traits are remained ambiguous. This would be speed up by molecular
tools. Despite the enormous potential, utilization of molecular markers in cannabis
breeding is surprisingly limited hitherto. Another constraint is the legal restriction for
growing the drug type cannabis all over the globe except Canada. Unequivocally, the
tremendous advent in the genomics of cannabis will dissect out the underlying genetic
architecture and hasten the progress in all those areas. Although, morphological
and phenotyping studies are also inevitable for understanding the developmental
phenology intricates in cannabis.

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Many valuable research in the citations

 

[acespicoli]

Build Your Farm and Future: Raising a Sustainable Meat Flock​

by Tom Watkins | Oct 23, 2022 | Education, Featured, Homesteading, Meat Birds, Tom Watkins

This article first appeared in the Fall 2022 issue of Homestead Living magazine.
Whether you are a backyard hobbyist or a full scale homesteader, my guess is that you have at least flirted with the idea of raising your own meat chickens. Perhaps you are still in the dreaming stage, or maybe you have already filled your freezer a time or two. Regardless, I bet you have looked at a Cornish Cross, gone through the logistics of shipping and timing, and thought, “I want to do this by myself.”
I hear the same complaints and comments all the time. “I’m just tired of having to rely on someone else. The hatchery never has them when I want them. Why can’t I just breed my own?” And, on one hand, I get it. I understand the desire to raise your own sustainable meat flock. In many ways, chickens symbolize freedom. Freedom from running to the grocery store on a Sunday morning when you’ve run out of eggs. Freedom to grab a chicken or two from the freezer for a special roast dinner. Freedom from relying on others to put food on your table when you want it.
But…I’m going to try to be as nice as I can with this one. The truth is: you can’t raise your own sustainable flock of Cornish Cross chickens, because you can’t breed them on your own. That can be really hard to hear, especially for those of us who have made it our life’s work to figure out how to do hard things for ourselves.
The truth of it is that in order to reproduce the most popular meat bird in North America, you would have to raise and care for thousands and thousands of chickens that you would never even think about eating. You’d have to spend your time planning out new breeding coops, evaluating and selecting parent stock, and you’d keep more records on your chickens than you could possibly imagine. Though many of us wish for the end result to be readily at our fingertips and in our backyards, we can’t always have our cake and eat it, too, folks. Most people don’t have the space, time, or long-term ability to start their own Cornish Cross breeding program from the ground up.
There is no way for the average person to replicate the meaty, broad-breasted bird that dominates as the most consumed meat in the country as you are used to it. And for the record, there are no genomic CRISPR-gene-editing mutant chickens responsible for the most common food source in the world. Cornish Cross are not a Franken-chicken lab experiment gone wrong. They are the result of generations upon generations of selectively breeding lines and parent stock.

Commercialization in the Meat Industry​

So what does this mean for us backyard homesteaders and working farmers, those of us who want to put dinner on the table for our families? Well … you know your family tree? Chickens have those, too. Instead of your Grandpa picking out your Grandma from all the other gals because she was the best dancer at the county fair, these chickens are selected for putting on weight as fast as possible.
In 1951, 60% of broiler breeders in the US were crosses of a Cornish (duh, Cornish Cross) and a New Hampshire. They weren’t white yet, they were actually red. This was the first market shift from dual purpose birds to strictly broiler breeding. With the rise in popularity of grocery stores, which is a story for a different time, people were no longer raising their own meat and eggs. This allowed for an industry solely dedicated to the specialization of meat chickens. Big corporations flocked to be a part of this new opportunity, and have controlled the breeding lines ever since. These major corporations at the top of the industry have about a 60 year head start on your passion for creating a Cornish Cross type breeding program.

Extreme Chicken Math​

It takes a hen to get an egg, and it takes an egg to get a chick. In the case of commercial broilers, it actually takes about 14 hens and 14 roosters (at least) to get a broiler. And for an extra layer of complication, only one sex is used from each specific line to produce the next generation. So, at best, half of the birds in each line are unusable within any given breeding program. For each broiler you dream of hatching at home and raising to butcher, you would have to raise 14-20 chicks to perpetuate each line, plus some for crossing for the next generation. The math gets pretty daunting when you talk about just how many birds are needed to avoid massive inbreeding within each line.
What does any of this have to do with why you can’t reproduce these particular broilers on your farm? You can absolutely raise your very own (delicious) sustainable meat flock, but only if you temper your expectations. At the end of the day, the Cornish broiler is a four way cross between eight breeding lines that are all heavily selected for growth rate. If you only want to replicate that grocery store slab of 10oz breast meat, don’t read any more. Cut your losses here, enjoy the fun fact that broilers used to be red, and order some Cornish Cross chicks to raise up for your table. There’s no shame in it, and many of us still choose to do it that way.

A Simple Solution​

What can we do to keep a full freezer, knowing that we can’t start our own Cornish Cross breeding program? The answer is very simple when you think about it. Do what your grandparents and great grandparents and great great grandparents did before commercialization defined every priority. You need to selectively raise a dual purpose flock that provides both meat and eggs. No, you won’t get chicken breasts that you have to split in half to cook. Again, temper your expectations. The tradeoff is creating a program that is better for you, the birds, and the environment. If you are determined, a sustainable meat flock that meets your family or community’s needs for delicious chicken tendies and Sunday roast spreads requires nothing but a little time and a lot of bookkeeping.
Start with good Heritage stock. Do what they did in 1951. Select two different breeds for different things. You’ve got your Cornish for breast size and easy plucking. There is a reason they used Cornish breeds back then and still do now. They have, by far, the largest proportion of breast meat to any other breed. And their beautiful, tight feathers pluck well. We sell both Dark and White Laced Red Cornish, which are sure to help you throw some rotund gals into the mix. Then, pick a large bird to pump up your lines. New Hampshires, Delawares, and Rhode Island Reds all have really nice rooster size. Now, let those two breeds dance to create some hybrid vigor, and you’re on your way to raising your own sustainable meat flock.

Record Keeping​

All breeders need to keep records, more than you might imagine. With cows and pigs, it might be a notebook. With chickens, you are going to need spreadsheets. So, so much data is involved in breeding chickens. The more you have, though, the more successful you are going to be in the long run. Records need to be kept by individual chick. No, I am not joking. I would never joke about chicken keeping records.
Records for each individual chick:

• Weight at 1 week
• Weight at 3 weeks
• Weight at 6 weeks
• Weight at 16 weeks (whoa…we are way off broiler specs here)
• Start of lay (normally 20-24-ish weeks depending on time of year)

Records for the whole flock:

• Hatchability for hens
• Fertility for roosters
• Number of eggs

Get Really Good at Building Breeding Pens​

Focusing on weight is the fastest way to progress a breeding program for broilers. It’s not the only consideration, but it is Priority Number One if you want a decent meat bird on the table at the end of the day. At every weigh-in, you need to cull the birds that are smallest. That doesn’t mean you have to off them right there, unless you are particularly hungry that day. Just move the pipsqueaks to a non-breeding pen, and eat them when they are bigger. I don’t recommend keeping small hens for layers, unless you’re only adding a handful of favorites back into a separate layer coop that you already happened to have. You are going to have multiple pens for chickens throughout this endeavor, and you won’t have space to keep all the unusable breeders. Yes, you are going to need to keep multiple pens. Those strapping New Hampshires you started with? They need their own pen. Those ever-so-handsome White Laced Red Cornish you took my advice about? They need their own pen. The offspring from those two lines? You guessed it. You see where I’m going with this…you’ll need a lot of pens to house a lot of birds, so it doesn’t make a lot of sense to hang on to the ones that don’t enhance your program.
Within each breeding pen, you need at least 50 hens and 6 roosters. That is the minimum number of birds I recommend for close breeding while keeping enough genetic diversity to not cause problems for about 10-20 years. You should be selecting for weight in each of these pens when you replace these flocks. Now, switch your roosters. Put the White Laced Cornish in with the New Hampshire ladies, and vice versa. Now those eggs are producing your hybrid cross.

Then Build Some More Breeding Pens​

You are going to need a pen for the offspring of those lines. The chicks from the two parent lines are going to have what is called heterosis, a fancy term for what some call hybrid vigor. This is a natural increase in size and growth rate, egg laying, and/or fertility that wasn’t present in the parent stock. This type of cross is known as an F1 cross. Two pure genetic lines mated create a hybrid. You need to keep all the same records for this group as your parent group. But here’s the tricky part. What do you do with this group? Breed them together? No, hybrids mated together don’t have the same characteristics, or pumped-up genes, that the first cross did. They don’t breed true. So, this group can be your table birds and egg layers. The increased size and growth rate of your hybrids make them a better option than either line of parent stock alone.
Let’s recap a little bit. You have two parent breed pens with 50-60 birds each, and just hatched an incubator full of their little adorable peeps. Now you have another 100 birds that are going to need a home for at least 20 weeks. This is probably a good time to ask how much chicken your family eats. Maybe we should have started with that…oh well, too late now! My family eats about 60-70 chickens a year, so that incubator could set us up nicely. You can butcher when males are roughly 16 weeks, and at about 20 weeks for females. Or, butcher the males and keep the females for egg layers until you need more nuggets. The better you are at selecting your breeders for size and growth rate, the sooner you’ll see their lines put size on, and the sooner you can butcher them. This is the whole reason you are here.

Lines A, B, C and D are pure bred lines. This might include a Cornish, a Plymouth Rock, or other non-Heritage breed. Lines can be the same breed, as long as they are genetically different.

Keep the Eggs Coming​

Do you need 200 birds a year? Easy, just hatch another batch in the incubator. If you are producing for your community, you can keep that baby pumping. The most realistic way to pay to support hundreds of chickens is to have a constant output. Find a market for your birds that makes them support themselves. You’ll go broke if you try to feed this many birds just for your own consumption.
When it comes time, you are going to need to replace your parent stock. Switch your roosters back so the New Hampshires are back with the New Hampshires, and so forth. This is called pure line mode. It takes about 2 to 3 weeks for the semen to dissipate from a hen from a previous mating (a fun party fact!) Once that time has passed, you are back in business. Now, to replace a breeding flock of 50 hens and at least 6 roosters, you are going to need about 400 eggs from each pure line.
Whoa there Timmy, that’s a lot of eggs to hatch! If you set 400 eggs and have a 75% hatch rate, you are now at 300 chicks. We can assume half of those are males, so you are at 150 hen chicks. And while that may seem like a lot, the number one rule in breeding chickens is to give yourself birds to cull. You are looking to retain only the exceptional for your breeding program. Keeping 1 in 3 is actually kind of low. If it was show birds, you should be keeping 1 in 25 or 50. This part is really important. Really. If you are not culling and keeping only the best and fastest growing, you are never ever going to do more than have backyard chickens.
If all of this sounds too daunting to begin with, you can totally keep just one flock of sustainable meat chickens. I would suggest a large bodied bird that lays well, like a Delaware (I know a guy with a few good lines.) All of the record keeping still applies, no matter what scale you are working on. I suggest you keep 100 hens and at least 20 roosters in a single flock setup. This is the smallest I like to go because it keeps the inbreeding stress off a little longer, for more like 20-25 years.

My Personal Tips for Packing on the Pounds​

There are a couple of tricks you can do that will help birds put weight on faster in any scenario or any breed. First, leave the lights on longer. Longer daylight hours means your birds will be eating more. Even just having a light on a timer that turns on for an hour in the middle of the night will spur them to eat. More food means more weight. The next tip is to keep your birds comfortable. No, I’m not suggesting that you air condition our chicken coop, but keeping their temperature regulated helps them grow out quicker. Less energy expenditure used to keep them warm means more weight gain. Less heat stress means they will eat more. I don’t like to eat when I’m sweating either.
And that’s it. That’s the whole deal. Keep records and cull really hard. Be relentless, select for size. Easier than calculating the half-life of radioactive isotopes.

Build Your Farm and Future​

At the end of the day, you can’t have that giant broiler chicken as a sustainable homestead alternative. But when you really think about it…why would you want to? It never was sustainable, the bird or the meat industry as a whole. You are fully and completely capable of raising a sustainable meat flock that meets your family’s needs. In doing so, I think you will find that even though your birds won’t be several meals within themselves, they are better tasting, and far better for you when raised under your own attention and care. I don’t think my grandma ever cooked a chicken breast on its own. But her chicken soup was glorious, and I remember it fondly still. The chickens of the past aren’t gone. They are as persevered in time as only Heritage birds can be. It’s our expectations that have changed, and what we gave up in the name of size is both health and taste. Convenience is nice sometimes, but it should not be the standard on which we build a farm and a future.



Random notes about line breeding and F1 vigor...

 

[acespicoli]

 

[Mimpi Manis]

Aspicoli, shoulders of giants and all that. You've been posting some interesting info recently. Just like you to know some of us (old guys!) appreciate you taking the time. My first etre' into the world of cannabis began with my first joint about 1968. Been growing for myself since I moved to my current area (Mediterranean climes) since 1980. Most impressive stuff I came across was thru 1970's in SE Asia. My first 'Buddha Stick' in 1975. Can only hope some of those extraordinary strains still exist. In 1981 I was gifted some seeds (in Broome) that turned out to be an early version of Skunk. (I think). That smell. Road kill indeed! No idea what I had at the time... but that stuff was the equal to some of those SE Asian strains. That idiotic war on drugs has a lot to answer for don't it? So many ignorant a-holes... so little time!

Last decade, my introduction to flower vapes motivated a concerted effort to learn more about all the famous strains I was reading about. That precipitated doing a little 'suck it and see' personal breeding. Damn, it sure is a rewarding little hobby aint it? I've been involved in self sufficiency and P/c for over 4 decades now, and cannabis is easily the most diverse, interesting plant I've dealt with. Possibly the ONLY genuinely effective plant medicine I have ever imbibed. (Invaluable for what I am dealing with currently). Anyway, just wanted to touch base. In a world drowning in bullshit and ignoramuses, real nice to see a bit of genuine and reliable information. Thanks man. Salute'. MM

 

[acespicoli]

New software helps plant breeders bring out their best | Cornell Chronicle

Cornell researchers have released a free, open-source software to help make potentially subjective and time-consuming plant breeding decisions more consistent and efficient.

news.cornell.edu

GitHub - zacharystansell/ratervar: R package for the analyses of rater variability and trait contribution to horticultural quality

R package for the analyses of rater variability and trait contribution to horticultural quality - GitHub - zacharystansell/ratervar: R package for the analyses of rater variability and trait contri...

github.com

Share your software, important pheno type traits, and lets map our strains ?

 

[acespicoli]

https://jcannabisresearch.biomedcentral.com/counter/pdf/10.1186/s42238-023-00178-9.pdf?pdf=button%20sticky

Stalk count per mm2 ???
For starters as well as a whole lot of other interesting traits.

 

[exoticrobotic]

Some very cool pics showing trichome development stages