Sex of plants

[WantDaChronic]

hijacked thread

 

well aquaponix and myself hijacked that thread so i decided to start a new one

 

A male takes a shorter period to finish requiring less soil food and light to do so. This is why I think stress in young plants creates more males. A harsher environment signals the plant to procreate faster so males arrive. The reaction of buds to a frosting of pollen is to finish (and of course turn to seeded shite) thus shortening the patch or crops potential life span.

 

Feminised seeds in bad conditions can produce male or hermies amongst them so how could the sex be completely predetermined.

Perfect conditions give me almost all girls from standard seed.

Bad conditions I get more boys, and even hermies.

 

those are quotes from aquaponix from the hijacked thread...basically i totally disagree and think that the sex is genetically determined. sure there are rare cases like feminized seeds producing hermies or maybe even a male, but i put that down to environmental stresses which can turn any plant hermie....

 

sorry if it sounds like im having a go at you aqua, i just figured if we were gonna talk about this some more, we should save El Badass's grow diary for him :smoke

 

so what is everyone else's thoughts on the matter?

[dsyfer]

This is what

 

"Marijuana Botany

An Advanced Study: The Propagation and Breeding of Distinctive Cannabis

by Robert Connell Clarke"

 

had to say about the subject

 

Many factors contribute to determining the sexuality of a flowering Cannabis

plant. Under average conditions with a normal inductive photoperiod, Cannabis will

bloom and produce approximately equal numbers of pure Male and pure female

plants with a few hermaphrodites (both sexes on the same plant). Under conditions

of extreme stress, such as nutrient excess or deficiency, mutilation, and altered light

cycles,  populations have been shown to depart greatly from the expected

one-to-one staminate to pistillate ratio.

 

A good read

 

You can buy it Here on Amazon

 

or read it online here

[Tom]

Sorry wdc, it's genetic, sort of like with X and Y chromosomes, the hermie trait in the wild is the environmental effect.

 

[Mushaman]

from what i read its genetic .... and may i add, I HATE MALES IN MY GROW ROOM!!

[WantDaChronic]

Sorry wdc, it's genetic, sort of like with X and Y chromosomes, the hermie trait in the wild is the environmental effect.

 

<{POST_SNAPBACK}>

 

no need to say sorry, thats what i was originally saying

 

Many factors contribute to determining the sexuality of a flowering Cannabis

plant. Under average conditions with a normal inductive photoperiod, Cannabis will

bloom and produce approximately equal numbers of pure Male and pure female

plants with a few hermaphrodites (both sexes on the same plant). Under conditions

of extreme stress, such as nutrient excess or deficiency, mutilation, and altered light

cycles,  populations have been shown to depart greatly from the expected

one-to-one staminate to pistillate ratio.

 

thats understandable, but wouldnt those stress factors just create more hermies?

[Frazz]

I find Aqua's theroy very credible....i did think it was genetic but im not so sure now

 

its coded into the plant as to when it decides to show its sex

and its not until it has enough information on its environment, that it determines which gender that will be

makes more sense from a survival point of veiw

 

:scratchin

[nitram]

I'm for genetic with stress (enviromenta) factors as expreamly influential.

 

RAPD markers encoding retrotransposable elements are linked to the male sex in Cannabis sativa L

by

Sakamoto K, Abe T, Matsuyama T,

Yoshida S, Ohmido N, Fukui K, Satoh S.

Genome. 2005 Oct;48(5):931-6.

 

Male-associated DNA sequences were analyzed in Cannabis sativa L. (hemp), a dioecious plant with heteromorphic sex chromosomes. DNA was isolated from male and female plants and subjected to random amplified polymorphic DNA analysis. Of 120 primers, 17 yielded 400 to 1500-bp fragments detectable in male, but not female, plants. These fragments were cloned and used as probes in gel-blot analysis of genomic DNA. When male and female DNA was hybridized with 2 of these male-specific fragments, MADC(male-associated DNA sequences in C. sativa)3 and MADC4, particularly intense bands specific to male plants were detected in addition to bands common to both sexes. The MADC3 and MADC4 sequences were shown to encode gag/pol polyproteins of copia-like retrotransposons. Fluorescence in situ hybridization with MADC3 and MADC4 as probes revealed a number of intense signals on the Y chromosome as well as dispersed signals on all chromosomes. The gel-blot analysis and fluorescence in situ hybridization results presented here support the hypothesis that accumulation of retrotransposable elements on the Y chromosome might be 1 cause of heteromorphism of sex chromosomes.

 

Link

 

One cause !

[Aquaponix]

I still think it's nature plus nurture as I stated. The sex may be predetermined but is alterable by environmental signals or triggers.

 

You accede that environmental factors may cause hermaphrodites, why couldn't the same environmental concerns alter other behaviour in the plant.

 

"Gross phenotypes and recessive variations within each trait will occur. In addition, these representations are based on unpruned plants growing in ideal conditions and stress will alter the gross phenotype"

 

Every cell on MJ has all the genetic coding it needs to grow however it wishes. I'm pretty sure MJ uses that whole array of choices according to it's environment. Given a stable environment you get your crop screw with that environment and those plants are still performing allright, they're playing the oldest game known, survival. And there you got a bunch of seeded.

 

I see no reason to conclude that plants able to adapt to environmental stresses in one way will not be able to do so in others.

 

Again, I'll never grow the numbers to hard test this.

[WantDaChronic]

You accede that environmental factors may cause hermaphrodites, why couldn't the same environmental concerns alter other behaviour in the plant.

 

because i think the plants have to be under alot of stress to actually change their sex...also, what about commercial grows? they can use thousands of plants, but if one were to hermie, the crop would be fucked...how do they get their grows totally seedless if the plants "know" there are only females growing? for some reason, i cant really see the plants giving a head count, nor could i believe at all that the plants are telepathic or have some other sense that tells them the male to female ratio in the surrounding area

 

im off the opinion sex change can happen in stressed conditions, but under normal conditions, the only way a plant can alter sex is if it has a shitty genetic line and hermies on its own which can be a result of using feminized seeds :thumbdown

[Aquaponix]

Yeah I don't like feminised seeds either. I do recognise the economic viability of increasing female production though hence the practise and prices. :thumbdown

 

Plants may not be telepathic but they are if I'm stoned enough

 

Large commercial grows of MJ would ideally have the correct conditions and be monitored closely. A female seems to 'prefer' bad conditions to hermie, or it just has bad genetics. A commercial grower would be foolish to buy bad genetic stock. Many cannabis crops have failed over time as well, some farmers are good, some are lucky, and then there's the hapless ones who strike every disease and pest known and a few new ones before learning the ropes (me but not as a farmer hehe)

 

From a market garden perspective. Knowledge, local knowledge (soil, pests, conditions and seasonal variations) good stock, good crop husbandry, (correct transplanting times and methods, soil mixes, nutes, seedling propogation) luck with nature and more all play a part in the success of a commercial scale operation. With conditions so good the female population has room to breathe and feed.

 

Wild crops have a tendency to drift genetically toward hermaphrodism, a survival trait. Only one seed needs to sprout to continue the species.

 

However, hermies detract from the original theory posed:

 

That environmental factors can play a part in standard (non-feminised) seed sex ratios.

 

This could be wrong, but it's not been proven wrong to my limited knowledge. My limited experience leads me to believe it might be true. If it's correct it is good news, if it's bollocks it still encourages good plant propagation ::

 

I remember last time I was wrong, back in 87, what happened was I thought I was wrong, but I wasn't. :thumbsup