Genome Has Been Sequenced

[Bushwacker]

Excellent posts!

Excellent posts!

Thanks Nunsacred & mofeta, for adding your thoughtful posts to this thread. Exciting and fascinating subject this is!

 

[foomar]

And then, maybe 10 years later, someone will have a MUCH improved marker set, capable of 'efficiently rescuing' superb subtle traits from heirlooms, and we'll wish we'd kept viable seed stock of that old Thai chemovar which took 17 weeks and was susceptible to mites.....but was heaven's own high....

Would they have to be viable or possible to extract the DNA from dead material ?
If so , could be possible to extract from a collection of pressed leaves or a scrap of ancient bud , like the one i recently found in an album sleeve where it had sat since 1971.

 

[Nunsacred]

I don't know, actually.
Generally the chromosomes hold together quite well but water/oxygen damage will eventually ruin it...
You could probably analyse nearly all of the big chromosomes from that sample if you had expert help and spent a couple of million.

AFAIK we couldn't currently resurrect that plant yet, might be wrong though.

Something I want to try sometime is to just look at the chromosomes in a nucleus of some of my plants, count them.
Needs a good microscope and a couple of lab chemicals.

1)snip the root tips off, soak them in alcohol,
2) then put them in a drip of acetic acid (lab grade vinegar) on a glass slide
3) poke with a pin and shake a bit to get the loose dividing cells out in solution,
4) remove the root tip, add a bit of 'orcein stain', put a coverslip on, warm for a few minutes and compress.
Then when you look under the microscope you can see cells and their nuclei.
The chromosomes are little black 'x's.
Depending on your skill and practice you can normally get one or two really nicely fixed ones where you can clearly see and count them.

It's not much use but it's still fun, apart from the smell of the vinegar.

They used to let genetics students look at their own nuclei like this, but then they got occasional shock results so they stopped it. I guess it's not much fun finding out you've got some weird sex chromosome number in front of a lab full of students.

 

[mofeta]

Something I want to try sometime is to just look at the chromosomes in a nucleus of some of my plants, count them.

Good post again!

Another way to do chromosome counts other than the root squash is a flower bud squash. It is more difficult, but you get to see the chromosomes paired up in meiosis.

I used to have an antique Bausch and Lomb microscope with an oil immersion setup, I wish I still had it.

 

[Nunsacred]

Good post again!

Another way to do chromosome counts other than the root squash is a flower bud squash. It is more difficult, but you get to see the chromosomes paired up in meiosis.

I used to have an antique Bausch and Lomb microscope with an oil immersion setup, I wish I still had it.

Hey, that would be cool and could possibly help us really advance our breeding stock.

Mofeta, I'm sure you are aware of "double haploid" plants in crop breeding....usually these are created in a lab using cell culture media but sometimes the right hybrid cross will do it naturally .... If we could find such a partner species for cannabis, we could all make true breeding stock and then use colloidal silver to self-set identical, immortal lines through seed.
We could avoid the need for clones?

So, using meiotic bud squashes to identify embryos in the second cycle, when they've lost one parental gamete, before doubling up.
That might be a lot harder than I imagine, but if it's not, we should get started.

There might be a chemical which would do it for a wide cross within cannabis, if the centromeres vary enough!
It's discussed in this short thread at 'Sensi' in 2010 I'd expect that there's a more 'natural' way of doing it though...

 

[foomar]

Page said analysis showed that the THCA synthase gene, an essential enzyme in THCA production, "is turned on in marijuana, but switched off in hemp."

Would the same dormant pathways still be present in modern hemp i wonder.

Some hybrid commercial hemp lines are bred to produce huge seed yields on vigorous compact plants for machine harvest , the structure is the same but near zero THC , wonder what would happen if it were possible to swtch on that gene in such a line.

That would really piss monsanto off.

 

[mofeta]

Mofeta, I'm sure you are aware of "double haploid" plants in crop breeding....

...That might be a lot harder than I imagine, but if it's not, we should get started.

There was a guy here named spurr (now banned) that was real interested in this process. Initially, I discouraged him from trying this (nontrivial process to put it mildly). He was very enthusiastic though, so I made a couple of threads to try to help him out:

Doubled haploids

cenh3 null mutation for Cannabis?

I never finished the second thread, spurr lost interest and the only other member interested was Chimera, and he is perfectly capable of just reading the paper himself.

 

[Nunsacred]

I'm talking about a natural way to do it.
Like with maize and barley, there might be a species whose pollen will sometimes give DH offspring naturally.

....identifying plants with same chromosome number "karyotype" as cannabis, whose CENH3 is sufficiently different, which can easily be grown alongside it, looking for hybrid seed.....

...it IS a major longshot isn't it?

 

[mofeta]

I'm talking about a natural way to do it.
Like with maize and barley, there might be a species whose pollen will sometimes give DH offspring naturally.

....identifying plants with same chromosome number "karyotype" as cannabis, whose CENH3 is sufficiently different, which can easily be grown alongside it, looking for hybrid seed.....

...it IS a major longshot isn't it?

Yeah, I think so. I respond in more detail over in the doubled haploid thread, HERE.