Polyploidism in Cannabis

[alphaomega]

Hi all, just thought ide share a friends triploid with you. ill post another pic soon as its a bit older now. he's hoping its female!!

[alphaomega]

Hi all, just thought ide share a friends triploid with you. ill post another pic soon as its a bit older now. he's hoping its female!!

 

sorry, ill get that pic asap just struggling with the upload

[alphaomega]

well couldnt get the upload to work for some reason.. i think its my broadband unit

[IceCube]

well couldnt get the upload to work for some reason.. i think its my broadband unit

 

Try sticking them on imageshack.us or make a picassa account man. Very interesting in seeing!

Edited November 3, 2010 by IceCube

[-YT-]

Are you sure its Polyploidism at all? and not whorled phyllotaxis?

Polyploidy occurs in cells and organisms when there are more than two paired (homologous) sets of chromosomes.

Most organisms are normally diploid, meaning they have two sets of chromosomes — one set inherited from each parent. Polyploidy may occur due to abnormal cell division during metaphase I in meiosis. It is most commonly found in plants. (Haploidy may also occur as a normal stage in an organism's life. A haploid has only one set of chromosomes.)

theres not much around about Polyploidism in canna the stuff that is from the 80s? or earlier and refers to the use of colchicine causing cellular division by inhibiting chromosome segregation, interestingly claimed triploid was poorer then orginal diploid but the tetraploid was stronger more yield etc also remembering colchicine is a deadly toxin that can kill humans fairly efficiently so yeah dangerous stuff

Phyllotaxis primarily refers to the arrangement of leafs on the stem and the pattern of that arrangement ie alternate, opposite, whorled or spiral. Canna goes from opposite in seedling to alternate in mature stage. So any plant with three or more leaf sets at the node is whorled phyllotaxis

ill try and find the study info and post

[-YT-]

Source icmag

Originally Posted by Robert Connel Clark

Polyploidy

Polyploidy is the condition of multiple sets of chromosomes within one cell. Cannabis has 20 chromosomes in the vegetative diploid (2n) condition. Triploid (3n) and tetraploid (4n) individuals have three or four sets of chromosomes and are termed polyploids. It is believed that the haploid condition of 10 chromosomes was likely derived by reduction from a higher (polyploid) ancestral number (Lewis, W. H. 1980). Polyploidy has not been shown to occur naturally in Cannabis; however, it may be induced artificially with colchicine treatments. Colchicine is a poisonous compound extracted from the roots of certain Colchicum species; it inhibits chromosome segregation to daughter cells and cell wall formation, resulting in larger than average daughter cells with multiple chromosome sets. The studies of H. E. Warmke et al. (1942-1944) seem to indicate that colchicine raised drug levels in Cannabis. It is unfortunate that Warmke was unaware of the actual psychoactive ingredients of Cannabis and was therefore unable to extract THC. His crude acetone extract and archaic techniques of bioassay using killifish and small freshwater crustaceans are far from conclusive. He was, however, able to produce both triploid and tetraploid strains of Cannabis with up to twice the potency of dip bid strains (in their ability to kill small aquatic organisms). The aim of his research was to "produce a strain of hemp with materially reduced marijuana content" and his results indicated that polyploidy raised the potency of Cannabis without any apparent increase in fiber quality or yield.

Warmke's work with polyploids shed light on the nature of sexual determination in Cannabis. He also illustrated that potency is genetically determined by creating a lower potency strain of hemp through selective breeding with low potency parents.

More recent research by A. I. Zhatov (1979) with fiber Cannabis showed that some economically valuable traits such as fiber quantity may be improved through polyploidy. Polyploids require more water and are usually more sensitive to changes in environment. Vegetative growth cycles are extended by up to 30-40% in polyploids. An extended vegetative period could delay the flowering of polyploid drug strains and interfere with the formation of floral clusters. It would be difficult to determine if cannabinoid levels had been raised by polyploidy if polyploid plants were not able to mature fully in the favorable part of the season when cannabinoid production is promoted by plentiful light and warm temperatures. Greenhouses and artificial lighting can be used to extend the season and test polyploid strains.

The height of tetraploid (4n) Cannabis in these experiments often exceeded the height of the original diploid plants by 25-30%. Tetraploids were intensely colored, with dark green leaves and stems and a well developed gross phenotype. Increased height and vigorous growth, as a rule, vanish in subsequent generations. Tetraploid plants often revert back to the diploid condition, making it difficult to support tetraploid populations. Frequent tests are performed to determine if ploidy is changing.

Triploid (3n) strains were formed with great difficulty by crossing artificially created tetraploids (4n) with dip bids (2n). Triploids proved to be inferior to both diploids and tetraploids in many cases.

De Pasquale et al. (1979) conducted experiments with Cannabis which was treated with 0.25% and 0.50% solutions of colchicine at the primary meristem seven days after generation. Treated plants were slightly taller and possessed slightly larger leaves than the controls, Anomalies in leaf growth occurred in 20% and 39%, respectively, of the surviving treated plants. In the first group (0.25%) cannabinoid levels were highest in the plants without anomalies, and in the second group (0.50%) cannabinoid levels were highest in plants with anomalies, Overall, treated plants showed a 166-250% increase in THC with respect to controls and a decrease of CBD (30-33%) and CBN (39-65%). CBD (cannabidiol) and CBN (cannabinol) are cannabinoids involved in the biosynthesis and degradation of THC. THC levels in the control plants were very low (less than 1%). Possibly colchicine or the resulting polyploidy interferes with cannabinoid biogenesis to favor THC. In treated plants with deformed leaf lamina, 90% of the cells are tetraploid (4n 40) and 10% diploid (2n 20). In treated plants without deformed lamina a few cells are tetraploid and the remainder are triploid or diploid.

The transformation of diploid plants to the tetraploid level inevitably results in the formation of a few plants with an unbalanced set of chromosomes (2n + 1, 2n - 1, etc.). These plants are called aneuploids. Aneuploids are inferior to polyploids in every economic respect. Aneuploid Cannabis is characterized by extremely small seeds. The weight of 1,000 seeds ranges from 7 to 9 grams (1/4 to 1/3 ounce). Under natural conditions diploid plants do not have such small seeds and average 14-19 grams (1/2-2/3 ounce) per 1,000 (Zhatov 1979).

Once again, little emphasis has been placed on the relationship between flower or resin production and polyploidy. Further research to determine the effect of polyploidy on these and other economically valuable traits of Cannabis is needed.

Colchicine is sold by laboratory supply houses, and breeders have used it to induce polyploidy in Cannabis. However, colchicine is poisonous, so special care is exercised by the breeder in any use of it. Many clandestine cultivators have started polyploid strains with colchicine. Except for changes in leaf shape and phyllotaxy, no out standing characteristics have developed in these strains and potency seems unaffected. However, none of the strains have been examined to determine if they are actually polyploid or if they were merely treated with colchicine to no effect. Seed treatment is the most effective and safest way to apply colchicine. * In this way, the entire plant growing from a colchicine-treated seed could be polyploid and if any colchicine exists at the end of the growing season the amount would be infinitesimal. Colchicine is nearly always lethal to Cannabis seeds, and in the treatment there is a very fine line between polyploidy and death. In other words, if 100 viable seeds are treated with colchicine and 40 of them germinate it is unlikely that the treatment induced polyploidy in any of the survivors. On the other hand, if 1,000 viable treated seeds give rise to 3 seedlings, the chances are better that they are polyploid since the treatment killed all of the seeds but those three. It is still necessary to determine if the offspring are actually polyploid by microscopic examination.

The work of Menzel (1964) presents us with a crude map of the chromosomes of Cannabis, Chromosomes 2-6 and 9 are distinguished by the length of each arm. Chromosome 1 is distinguished by a large knob on one end and a dark chromomere 1 micron from the knob. Chromosome 7 is extremely short and dense, and chromosome 8 is assumed to be the sex chromosome. In the future, chromosome *The word "safest" is used here as a relative term. Coichicine has received recent media attention as a dangerous poison and while these accounts are probably a bit too lurid, the real dangers of exposure to coichicine have not been fully researched. The possibility of bodily harm exists and this is multiplied when breeders inexperienced in handling toxins use colchicine. Seed treatment might be safer than spraying a grown plant but the safest method of all is to not use colchicine. mapping will enable us to picture the location of the genes influencing the phenotype of Cannabis. This will enable geneticists to determine and manipulate the important characteristics contained in the gene pool. For each trait the number of genes in control will be known, which chromosomes carry them, and where they are located along those chromosomes.

[Bread Filter]

I remember seeing some photos of Colchicine treated seeds that were grown into some crazy mutant looking plants. They still looked more like Cannabis than the Ducksfoot and Aussie Bastard Cannabis strains do.

[planthelper]

i know a polyploid, the mangosteen!

i think multy embryonic mangoes are a bit similar??

and for this reason it's seeds form true to type fruits, they perfectly clone themselfes, is that what it means in laymans terms?

from this site:

http://www.montosogardens.com/garcinia_mangostana.htm

It is hypothesized that mangosteen is a polyploid that arose from natural hybridization between Garcinia hombroniana y G. malaccensis.

[alphaomega]

-YT- i think ur right.. anyway, i uploaded the pic to imageshack:

http://img41.imageshack.us/img41/3404/sdc10093bn.jpg

[alphaomega]

-YT- i think ur right.. anyway, i uploaded the pic to imageshack:

http://img41.imageshack.us/img41/3404/sdc10093bn.jpg

 

if that one doesnt work: http://yfrog.com/15sdc10093bnj

[Magicdirt]

I'd bet ten bucks it's not polyploid.

I think it is just a trifoliate specimen, which happens sometimes.

There was a lot of interest in polyploidism in the 80's and people were chasing Meadow saffrons for the colchichine but I've never seen a true polyploid plant personally. Apparently a mutated polyploid plant will tend to throw normal haploid offspring (if the mutated plant wasn't hermaphroditic) so the genes don't tend to stay around for long. There was talk of the Mullumbimby madness strain being polyploid but I can't remember anyone presenting any evidence.

Everytime I've seen a trifoliate plant it has turned out to be a male.

Let us know how it turns out and what sex it is.

[alphaomega]

I'd bet ten bucks it's not polyploid.

I think it is just a trifoliate specimen, which happens sometimes.

There was a lot of interest in polyploidism in the 80's and people were chasing Meadow saffrons for the colchichine but I've never seen a true polyploid plant personally. Apparently a mutated polyploid plant will tend to throw normal haploid offspring (if the mutated plant wasn't hermaphroditic) so the genes don't tend to stay around for long. There was talk of the Mullumbimby madness strain being polyploid but I can't remember anyone presenting any evidence.

Everytime I've seen a trifoliate plant it has turned out to be a male.

Let us know how it turns out and what sex it is.

 

thanks magicdirt, and i shall keep you posted.

[alphaomega]

Here is a photo of the plants progress: http://yfrog.com/mu08112010002j

so far it hasnt changed to two leaves at each node..

[-YT-]

a botanical and semantic nightmare

Trifoliate refers to the leave number NOT the number of petiole/leaf sets per node

Edited November 8, 2010 by -YT-

[Magicdirt]

Woops

Edited November 8, 2010 by Magicdirt