trick for controlling hormones on unstable strains

[Adze]

The YouTube link above is really very interesting and well worth 30 minutes of your time, intelligent man delivering a lot of information.

Regarding hormones signaling the expression of inter-sexed traits, I have a question...
Have you ever seen a plant "hermie" after being pollinated?

 

[trichrider]

not

 

[TnTLabs]

The YouTube link above is really very interesting and well worth 30 minutes of your time, intelligent man delivering a lot of information.

Regarding hormones signaling the expression of inter-sexed traits, I have a question...
Have you ever seen a plant "hermie" after being pollinated?

a hermie will still put out bananas after being pollinated..
seen it couple of times
english rick might be onto something.. would need to try
but rather toss em

 

[Arf]

I grew out half a dozen of Skunkman's Sk#1 last year, they were from a freebie batch Gypsy sent out about 15 years ago. All 4 females developed a few bananas in the top buds about 60 days into flower. What causes that? What's going on "under the hood"?

I was using Maxibloom last year for the first time, that's the only real change. I have never seen bananas before that, only occasional sparse hermie flowers on the stem of a few strains in early flower.

 

[Darpa]

Hi everybody, I thought that I could probably jump in and share some thought with you guys (from a biochemist that think this is an interesting topic).

Unfortunately, there is no scientific evidence that support the assumption that exposing your female elite plant to a male may or will reduce the occurrence of hermaphroditism trait of the female population bases on the fact that chemical information will be transferred from the male plant to the surrounding female, (or as you describe it; male "pheromone" in the environment may affect the plant hormone of surrounding female).

The sexual phenotype of Cannabis often shows some flexibility leading to the differentiation of hermaphrodite flowers or bisexual inflorescences (monoecious phenotype). However this phenomenon is directly linked with both the plant genetic (chromosome), and the environmental condition. On an evolution point of view, the ability of a female plant to scent the absence of a male in its surrounding environment is not supported, since this evolution adaptation would have require the lack of male genetic in native plant population. Since sincemilla grow is new, on an evolution time scale, there would be no natural pressure for this new fitness phenomenon to appear as a new adaptation… Also, we should remember that Cannabis has a diploid genome (2n=20) with a karyotype composed of nine autosomes and a pair of sex chromosomes. A general belief suggest that Female plants are homogametic (XX) and male plants are heterogametic (XY). However, in these plants, sex expression is controlled by an X-to-autosome (X/A) balance system and not exclusively from the Y chromosome (confirmed from polyploidy essay)… The sex, is not determined by particular chromosomes, but by the genome assembly, and by the gene and chromosome interactions. All individuals are, in this manner, able to express one or the other sex. It was previously shown that sex expression also depends on different environmental factors and can be reversed by the application of plant growth regulators.

The following models were established:
- male plants with male inflorescence: X/Y, Xm/Y;
- male plants with female inflorescence, Xm/Xm;
- variable phenotypes, from true females to monoecious plants, but all with female inflorescence, Xm/X;
- female plants with inflorescence of female type, X/X

So if you get a clone only strain that may contain the Xm allele, you may end up with male inflorescence that may be activated from environmental factors…

So, in conclusion, if you don’t work with a true female X/X, you should pay good attention to the environmental stressor (light spectrum, plant density, temperature…etc) since all these variable will affect the predisposition of you plant to show intersex trait.

I hope that it help!

 

[Darpa]

The concept discussed in my previous post is even more critical if you are involve in a breeding project. Several precaution must be taken to exclude the Xm allele to be transferred to the descendant, this is especially important if one of the parent use in the cross is hemi prone. Tony’s work with the Gorilla Bubble is a good example of what I’m talking about (stress induced selection).

 

[Tonygreen]

GB would/could have been a disaster without it!

 

[GMT]

Given the evidence that's been well presented and sources given in numerous threads, can you cite a source for your claims DARPA? Active Y is the established view, genetic testing is done based on y specific markers for determining sex rather than some x to autosome calculation.

 

[Darpa]

Given the evidence that's been well presented and sources given in numerous threads, can you cite a source for your claims DARPA? Active Y is the established view, genetic testing is done based on y specific markers for determining sex rather than some x to autosome calculation.

Hi GMT, There is nothing new with this concept and it’s well documented in the scientific literature for cannabis, hemp and hop. Of course the Y chromosome will influence the sex determination of your plant, but the X\autosome ratio will also have an influence, specially with you female (hermaphrodite trait)...


Gender and Sexual Dimorphism in Flowering Plants, MONICA GEBER, Todd E. Dawson, Lynda Delph, Springer Science & Business Media, 6 déc. 2012 - 305 pages





Grant et al., 1994 concluded that the hemp has a sexual determinism based soon on X/autosomes equilibrium and not on a Y active mechanism.

Ainsworth, 2000 describes sex determination in the genus Cannabis as using "an X/autosome dosage-type.

Frankel and Galun, 1977 affirm that the males are X/Y, and the females are X/X. Besides that, the allele Xm exists, that determines the appearence of male flowers in female inflorescence. Thus, X/Xm plants have female inflorescence, but they can be not strictly females. Depending on genetic and non-genetic additional factors, these plants tend to masculinization, reason for which Kőhler named them “subgynoecious”. The Xm/Xm plants will have female inflorescence, but functionally are males. Considering the results obtained in various studies on polyploids by other researchers, Kőhler concluded that the masculinizing genes are autosomal and they are balanced by femaleness carrying genes of X chromosome, while the Y chromosome is “empty” under the aspect of sex determining genes.

An analogy could be made with Hop where polyploidy test confirmed the X\autosome relationship in sex determination:

Humulus lupulus possesses sex chromosomes. Female plants are homogametic with 2n¯18*XX, whereas male plants are heterogametic with either simple XY or multiple sex chromosome systems. Sex expression in hop appears to be regulated by an Xautosome balance system (Neve, 1961). This type of sex determination system is found in only two other genera, Cannabis and Rumex (Parker, 1990) and contrasts with the active Y-system found in some Silene species, in which the Y-chromosome specifies maleness (Westergaard, 1946, 1958). A ratio of the number of X-chromosomes to the number of sets of autosomes of 0.5 gives rise to a male plant; a ratio of 1.0 gives a female, while intermediate ratios give rise to intersexual individuals.

Sexual development and sex chromosomes in hop, H. L. SHEPHARD", J. S. PARKER#, P. DARBY$ C. C. AINSWORTH"*
"Plant Molecular Biology Laboratory, Department of Biology, Imperial College at Wye, Wye, Ashford, Kent TN25 5AH, UK #University Botanic Garden, Cory Lodge, Bateman Street, Cambridge CB21JF, UK $Department of Hop Research, Horticulture Research International, Wye, Ashford, Kent TN25 5AH, UK
Received 28 April 2000; accepted 7 July 2000

 

[Darpa]

I hope this help to clarify my claim...

 

[GMT]

Quite a detailed reply, about cannabis hemp and hops. Not much discussion on any one in particular though, which is a pitty as the differences are important.
The terminology of sexual determination and the observable appearance of flowers is also something else that could do with clarification though, as one seems interchangeable with the other as your text stands.
The observation of a male flower on a female plant is not relevant to the sex of the plant, but the result of an undesirable gene or two. The sex is determined by the presence or absence of a male chromosome in at least one of the (in hemp I believe the count is one y silences 3 x's in tetraploid species) and in diploid cannabis, 2 sexually determining chromosome positions.
The old thinking of x to autosome has been argued to death on this board, and the threads should be easy to find. Really the active Y is the only one accepted nowadays.

 

[Cannabologist]

... So.. This kinda confuses the intersex issue GMT according to what you are saying. Any more clarification on this?

A mechanism where in you have X/X, X/Y, and Xm/X (which is for a female that can intersex), seems to make a lot of sense... The genetics for which would turn out something like this >

If you Punnet square all this out you get..

X/X (x) Xm/X >>> 50% X/X and Xm/X offspring in the F1,

The F2 gets nuts, or things just start going south, if you cross an intersex with an intersex...

Xm/X (x) Xm/X >>> 25% X/X (ie females), 50% Xm/X intersexing females, and then 25% Xm/Xm, ie REALLY intersexing females, ie. likely what is monecious cannabis.

This makes a lot of sense from especially my own experience with intersexing plants and "true" females.. Anyone have anything else to offer since dagnabit its 2017 we should all have this figured out by now BUT we're all fucking stone heads. Fucking lazy ass stoners.

 

[Darpa]

Quite a detailed reply, about cannabis hemp and hops. Not much discussion on any one in particular though, which is a pitty as the differences are important.
The terminology of sexual determination and the observable appearance of flowers is also something else that could do with clarification though, as one seems interchangeable with the other as your text stands.
The observation of a male flower on a female plant is not relevant to the sex of the plant, but the result of an undesirable gene or two. The sex is determined by the presence or absence of a male chromosome in at least one of the (in hemp I believe the count is one y silences 3 x's in tetraploid species) and in diploid cannabis, 2 sexually determining chromosome positions.
The old thinking of x to autosome has been argued to death on this board, and the threads should be easy to find. Really the active Y is the only one accepted nowadays.

Hi GMT,
The active Y chromosome concept for sex determination in the Cannabis plant may be the only one accepted on this forum, but with all respect, I believe that there is not too many plant geneticist or biochemist that contribute on these thread. I am not ready to say that the Y-active concept in the only one accepted nowadays, at least in the scientific community. In fact all the evidence support the X-autosome theory. I’ll try to explain my thought, but I’m not here to convince you and it’s ok if we disagree… I respect you opinion.


Cannabis plant is dioecious plant with heteromorphic sex chromosomes (Sex chromosome X and Y):

In a small number of species, sex chromosomes have been seen that are structurally different over most of their length. Few species have been confirmed cytologically to have sex chromosomes and Cannabis is one of them. However, the genetic mechanisms regulating gender are diverse rather than similar even in this small number of species. This demonstrate that sex chromosome have evolved from autosome pairs independently in different plant lineages.

So I guess that we agree that Cannabis plant have sex chromosome.


The sexual determination of Cannabis is not based on an Y active mechanism ???:

I guess that we’ll agree that the presence of a Y chromosome in a diploid Cannabis plant would result in a male plant at 100% of the time. We are getting one step closer to an agreement …


However, you stated that the sexual determination of Cannabis is based on the Y ACTIVE MECHANISM, which imply that active genes on the Y chromosome are directly implicated in the process. It’s where I don’t agree.


The Y chromosome is “empty” under the aspect of sex determining genes:

The X/autosomes equilibrium is responsible for the sexual determination of Cannabis and the Y chromosome is not directly linked in the process. The mechanism involve the presence of activators genes on the X chromosome and negative regulation encoded by the autosomes. In simple words, positive elements to activate a female developmental pathway exist on the X chromosome and these are balanced by element that favor male developmental program located on the autosomes. That mean that with the lack of an X chromosome in a XY plant the positive elements produced by the solitary X chromosome won’t be sufficient to counteract the effect of suppressor encoded by the autosome and you will end up with a male plant.

If the sexual determination of Cannabis would be based on the Y active mechanism concept, how would it be possible to induce a male diploid plant (XY) to produce female flower?

(Induction of female flowers on male plants of Cannabis Sativa L. by 2-chloroethanephos-phonic acid, HYM Ram, VS Jaiswal - Cellular and Molecular Life Sciences, 1970 – Springer)


I don’t know if it make sense?

 

[GMT]

Ah, no its the other way around mate. The suppressing genes are located in the sexual determination chromosomes, the genes for floral expression are in the autosomal region. That's why you can mimick the presence of a Y by the introduction of a suppressing agent. The code for both types of flower are contained in the auto some, which of them are activated, is determined by the presence or absence of the male chromosome. Hence active Y.
Expression is down to the interaction of the sex chromosomes and the auto some, in their environment, which is why you hear botanists talk about x to auto some, but geneticists are concerned about inherited determination of the offspring.
Determination is down to active Y.
That's the only way I can express my position.

 

[Cannabologist]

Wellp I'm baked and confused.

This is a horrible condition.

Ok GMT... What's your Punnet Square then for intersexing plants?.. Or any plants I guess? Well figuring XX/XY is pretty easy lol..

So you are saying intersex(ing) plants have a Y chromosome..? (I'm probably misreading that...)..
Idk you need to explain that more cause I just tried to think it through and explain it and nope I deleted that paragraph it was gobbledygook.

Meow. meow meow.


OKAY You 2! I hate to be a nazi but it's about to be PAPERS PLEASE! lol And then we can perhaps hash this all out because both of what you say makes sense and I think there is a middle ground here...

I have a lot of these same papers too I'm sure, I'd have to go through them again. Maybe I'll make a call to Med Genomics tomorrow or soon and get some opinions there.. Hm.

And keep it simple I'm baked. They say I'm smart yeah okay maybe. Idk. I'm baked.

 

[GMT]

Hey canna, no I'm saying some of them do. Intersex flowers are the result of something undesirable being in the overall genome somewhere. If we can agree on that, the rest is easy, but not all do. That maybe an error or mutation that is not contained in every example. It may be in one of the sex chromosomes or somewhere in the auto some. Its like a car's brakes, if there's a fault, it doesn't matter where it is, the result is the same.
We are really talking about the cause of maleness rather than the cause of the appearance of male balls. Which are different things.
Chimera has done some in depth testing himself apparently, here's his take on it


https://www.icmag.com/ic/showpost.php?p=5341665&postcount=178
I wouldn't read the whole thread, it got messy, but its from here
https://www.icmag.com/ic/showthread.php?t=231950

 

[Darpa]

Ah, no its the other way around mate. The suppressing genes are located in the sexual determination chromosomes, the genes for floral expression are in the autosomal region. That's why you can mimick the presence of a Y by the introduction of a suppressing agent. The code for both types of flower are contained in the auto some, which of them are activated, is determined by the presence or absence of the male chromosome. Hence active Y.
Expression is down to the interaction of the sex chromosomes and the auto some, in their environment, which is why you hear botanists talk about x to auto some, but geneticists are concerned about inherited determination of the offspring.
Determination is down to active Y.
That's the only way I can express my position.

Hi GMT!
Ok, since the majority of scientific research are performed on hemp vs Marijuana, I just want to state that the sex linked genes expression in female Cannabis flower (Drug cultivar) are similar to the one in the diocious hemp. That been said…,

There are several excellent recent reviews of sex determination of diocious plant and cannabis genus. I would suggest:

Boys and Girls Come Out to Play: The Molecular Biology of Dioecious Plants, Charles Ainsworth, Ann Bot (2000) 86 (2): 211-221.

The regulation of sex determining gene as you refer to is similar to the regulation observed in Silene latifolio. However, Cannabis show a different type of regulation:

The increased length of the Y chromosome in hemp (Yamada 1943 cited by Sakamoto et al. 1995) suggests some similarity with the sex chromosomes of Silene latifolia (Sakamoto et al. 1998; Fig. 2.5). In this latter species, males have XY and females XX sex chromosomes (Dellaporta and Calderon-Urrea 1993). The structure of the Y chromosome is characterized by a non-pairing region including sex-determining loci and a pairing, pseudoautosomal, region which undergoes recombination with the X chromosome during meiosis. The non-pairing region of the Y chromosome contains female suppressing, male promoting and male fertility regions (Westergaard 1953 cited by Di Stilio et al. 1998; Charlesworth 2002). The sex determinism in Silene is based on an Y-active system, with dominant male factors and female suppressing factors mapping to the Y chromosome (Dellaporta and Calderon-Urrea 1993). In contrast, in hemp, the sex determinism is based on a X-to-autosomes system. In addition, the genetic basis of sex determinism in Silene is strong and shows little evidence for lability or environmental effects (Ainsworth 2000), while hemp displays a high plasticity of sexual phenotype.


Here is a good PhD thesis on the subject:
QUANTITATIVE APPROACH OF THE GENETIC DETERMINISM OF SEX EXPRESSION IN MONOECIOUS HEMP (CANNABIS SATIVA L.), AND ITS RELATIONSHIP WITH FLOWERING PHENOLOGY AND STEM AND SEED YIELDS

https://dial.uclouvain.be/pr/boreal/object/boreal:142449/datastream/PDF_01/view

The sex determinism in dioecious hemp would be based on an X-to autosomes equilibrium and not on a Y-active mechanism (Westergaard 1958; Ainsworth 2000). This assumption agrees with the experiences carried out on polyploid hemp individuals (Warmke and Davidson 1944).

The X-to-autosomes system of sex determination is based on the ratio of the number of X chromosomes to the ploidy level. This system can explain why hemp polyploid individuals with XXY and XXXY formulae are female or female-hermaphrodite, and XY, XXYY and XYY individuals are male (Warmke and Davidson 1944).


The Y chromosomes are not necessary for the production of male flowers; moreover, the pollen can mature and be viable in the absence of Y chromosome.

The diversity of intersexual forms, the bipotency of sexually predetermined plants and the occurrence of fertile male flowers on female plants of dioecious hemp suggested that the sex in hemp would be determined by the activity of genes that are located not only on the sex chromosomes but also on the autosomes (Grisko 1937 cited by Truta et al., 2007; Sengbusch, 1952 cited by Westergaard, 1958; Rath, 1968 cited by Truta et al., 2007; Migail, 1986 cited by Mandolino and Ranalli, 2002). Grişko (1937 cited by Truta et al. 2007) considers that the determinants of phenotype and those of sexualisation are independent since female plants are able to produce male flowers under given environmental conditions. The ability to reverse the sex determination mechanism by hormonal treatment suggested that sex determination genes could regulate alternative programs of sexuality through a signal transduction mechanism that modifies endogenous hormonal levels (Dellaporta and Calderon-Urrea 1993).



Markers, referred to as MADC, for male-associated DNA sequence in C. sativa:

Hybridization of DNA from male and female plants by southern blotting analysis revealed either the absence of no sex-linked polymorphism (Mandolino et al. 1999), either multiple bands among which only few are male-specific (Sakamoto et al. 2000; Torjek et al. 2002; Sakamoto et al. 2005). Similarly, the in situ hybridization of chromosomes with the MADC3 and MADC4 sequences produced signals dispersed on all chromosomes and thus not specific of the Y chromosome. Thus multiple sequences encoding retrotransposable elements should exist ubiquitously in the genome of C. sativa (Sakamoto et al. 2005). This appears in agreement with the view of Clark et al. (1993), who observed no major difference in the distribution of repeated DNA sequences between X, Y and autosomes in Rumex acetosa, a dioecious species with heteromorphic sex chromosomes. According to Charlesworth (2002), the abundances in repeated DNA in plants bearing sex chromosomes would be mostly similar on both sex chromosomes and autosomes.

 

[GMT]

I don't think that guy will or should have got his doctorate on that interpretation. X chromosomes to ploidy level is active y. That's what active y is. X to auto some is the alternative. And that's expression or phenotype not determination. Determination is code, expression is interaction with environment. Expression can draw upon many sub routines, mostly dormant, but environment can trigger them, as can mutation.
The problem is, to a botanist, anything that expresses male flowers, has a code that produced them and therefore determined their existence, and so a female in certain conditions producing male flowers, is genetically predetermined to produce male flowers. Clearly nonsense but botanists don't understand logic, if they did, they would be scientists.