is this how you breed quality genetics?

[Weird]

im sure it was neither and you missed the point entirely as did he

it has nothing to do with revising breeding numbers but everything to do with calculating the
differences in frequency of expression due to environment influences

stop trying too hard to contest my meaning when you don't even understand it

 

[xmobotx]

if that's the posts i remember it was more of a "that's not what we are talking about here/this is more important ~we'll get to that later" than; "no environment doesn't matter!"

he might have said environment doesnt matter ~which is to say 'for the sake of this discussion'

obviously; g+e=p but the 'g' part {maximum potential} is a better option than eeking the most out of a hay strain

 

[Weird]

what makes you think the concepts are mutually exclusive, you guys think in a different context

grow some so DJ's gear in it's target environment and grow some of it in an unprefereed environment and tell me how me if you get the same percentage of desirable phenotypes and if they occur in the same frequency in like number of seed pools

 

[xmobotx]

how about grow some ditch weed that doesnt get you high in a state of the art grow facility and compare that

most of us are working in the same type of controlled environ and many are even using the same lights {to brand ffs}

nonetheless; you need to understand the punnet square stuff and how traits pass e.g. recessive, incomplete dominant, dominant ~those #s will get us where we want to be w/ our progeny and then we'll try that in our best environ

somewhere along the line we'll address self'n, bx'n and outcross/topcross crap but all the above is going to help w/ that before we try the best environ

are you ref'n environ as it applies to hermis?

 

[Infinitesimal]

im sure it was neither and you missed the point entirely as did he

it has nothing to do with revising breeding numbers but everything to do with calculating the
differences in frequency of expression due to environment influences

stop trying too hard to contest my meaning when you don't even understand it

Ok, but lets "pretend" that I did understand for a second... besides measuring prepotency, what are the breeding implications of "calculating the differences in frequency of expression due to environmental influences"?

cause phenotypic expression only tells us so much, since heterozygous individuals express themselves but aren't near as valuable for breeding purposes'

the genes are responsible for all the possible expressions, and changing the environment and subsequently the expression doesn't change the genes... so the goal remains the same, to work toward homozygosity for desired traits so the the progeny have the genes necessary to express the desired traits.

making a clone or a seed stock express itself differently makes little to no difference unless the bias for that expression is maintained generation after generation and the traits are worked towards homozygosity.


Breeding = Identifying homozygous individuals

 

[Infinitesimal]

what makes you think the concepts are mutually exclusive, you guys think in a different context

grow some so DJ's gear in it's target environment and grow some of it in an unprefereed environment and tell me how me if you get the same percentage of desirable phenotypes and if they occur in the same frequency in like number of seed pools

what make you think no one can understand the "massively complex" ideas of yours... I understand what you are saying about Dj's dear... but its the genotype that counts in breeding... here let me quote myself to make it easier for me...

great example...

BUT...

this is the point... you are talking about cultivation... and yes you can change the expression... but when you pollinate it, it passes on the same genotype regardless... triggering a different expression does not cause a different gene to be passed on to its progeny.

I thought you were smarter than this, weird....
unless it effects selection of a mate which effects the recombination of genes and subsequently the offsprings genotype then it plays little to no role in breeding.

 

[Weird]

how about grow some ditch weed that doesnt get you high in a state of the art grow facility and compare that

why not simply answer the question i posed with an answer not a question

have you grown DJ's gear? I have its sensitive and if you treat it accordingly it expresses wonderfly if you dont you may not be able to appreaciate the plant

most of us are working in the same type of controlled environ and many are even using the same lights {to brand ffs}

selection in a target environment is great but how are you testing genotype diversity outside of those environments?

your not, so how does that difference in expression effect selection if your not using gene marking technology or by testing in multiple environments?

why is there a growing trend in participatory breeding programs where breeding candidates for improved cultivars are selected from within their target environment?

nonetheless; you need to understand the punnet square stuff and how traits pass e.g. recessive, incomplete dominant, dominant ~those #s will get us where we want to be w/ our progeny and then we'll try that in our best environ

how about the effect of environment to express those traits?

and who determines the best environment?

there is one predetermined by the plants genetic code, one we can duplicate which will ensure it expresses its full potential and there is the one we are capable of providing

these factors express the frequency of expression in breeding programs potentially negatively or positively

somewhere along the line we'll address self'n, bx'n and outcross/topcross crap but all the above is going to help w/ that before we try the best environ

are you ref'n environ as it applies to hermis?

no and not in how does it effect ratios such as 9:3:3:1 but how does it effect FREQUENCY of expression

i can show you rooms of plants that all look the same (seed sisters from various strains) and I can show you some of the same phenotypes in various environments and the expression is completely different

i can even do the same think with some elites

most people aren't breeding for some gene markers but they are breeding for all these various traits they can identify with there 5 senses

environment effects the plants and we are going by what we see, smell, taste etc

go take chem d and grow it in 5.9 -6.2 ph and grow another in outside that range and tell me if you would select one as potential cultivar and if you would ditch another because it wasn't desirable

cultivar worth is relative to its performance in the target
environment

there is a reason many breeders have a contingent of people who love their work and those who dont and im sure some of that disconnect has to do with environmental difference

a proper breeding program that isn't improving a cultivar for local performance would benefit from running its progeny in several different environments and making selections based on performance across all environments (as it is done in the "real" world) versus breeding programs that are aimed at local cultivar performance and improvement (also "real" world) where you would select candidates based on best performance in said target environment

either way each breeding scenario would choose a different candidate to breed upon

 

[Weird]

what make you think no one can understand the "massively complex" ideas of yours... I understand what you are saying about Dj's dear... but its the genotype that counts in breeding... here let me quote myself to make it easier for me...



I thought you were smarter than this, weird....
unless it effects selection of a mate which effects the recombination of genes and subsequently the offsprings genotype then it plays little to no role in breeding.

thats the whole point, environment does effect expression and since we select based on expression and not gene markers the influence of the environment matters in selection

you cant remove its influence in traditional breeding programs

kinda funny you treat math to the minutia but glaze over effect of environment on expression and thus selection

the point with DJ's gear in particular is that I found it was environmentally particular and that the same cut could either shine or be quite mediocre based on the environment provided

as far as i am concerned the man is a genius but there are many people who just dont "get" his work because they haven't replicated the same experience with the same genes

if g + e = p and everyone is using the same genotype what is left to bias the outcome?

 

[xmobotx]

the thing is weird; no one is arguing these points ~you are manufacturing strawmen in your discussion here

everyone can accept that certain lines are more sensitive to environ triggers especially w/ regard to hermaphrodites

for you to say that i'm not testing different environs is an assumption on your part but it doesnt matter what i m doing {although about the only thing i havent tested is HID}

anyway your thing is environment environment environment ~as we've gotten in to before and yet; after all that ~we're not really discussing environ here/we're discussing genetics

AND as I've mentioned~ the environ considerations come after the genetics just like the epigenetics come after the genetics

all this environ discussion does right here is cloud the water

I know; it's the consummate argument environment vs genetics ~it's far older than us or anyone else living today ~i just dont see why we cant separate it into a complimentary distinguished convo and hash out the genetics stuff here minus the environ arguments

 

[Infinitesimal]

thats the whole point, environment does effect expression and since we select based on expression and not gene markers the influence of the environment matters in selection

you cant remove its influence in traditional breeding programs

kinda funny you treat math to the minutia but glaze over effect of environment on expression and thus selection

the point with DJ's gear in particular is that I found it was environmentally particular and that the same cut could either shine or be quite mediocre based on the environment provided

as far as i am concerned the man is a genius but there are many people who just dont "get" his work because they haven't replicated the same experience with the same genes

remember when you were talking about the professionals you work with who were to caught up in their "expertise" that they couldn't see outside their current mode of thought... its kind of ironic now.

I dont discount the effect of the environment one bit, go back a few pages and reread my post's... but it is far from an end all say all.

you see, you keep talking about getting the best expression from the cultivar... but that is the goal of a cultivator... of course a breeder is a cultivator first so finding the best expressions is sort of moot point, but the overall goal of a breeder is to find individuals that breed true for the genes responsible for those expressions, so to guarantee that the majority of the offspring when raised in a conducive environment express those traits. Further more how do you determine if the expression of a males phenotype "shines" or is just mediocre without first making a test cross and growing out it's progeny?

and I am a huge DJ follower and believer of his methods, but just maybe I understand them differently. tweaking your environment can help especially with a large population size and when all the other methods are followed, but is more the Icing on the cake rather than main course.

FWIW, breeders don't just make selections based on expression, they make several test crosses and make their selections based on the results of the progeny... THATS the BIG PICTURE, that you seem confuse for the framework... isolating, making test crosses and growing the progeny are at the forefront.

if g + e = p and everyone is using the same genotype what is left to bias the outcome?

well first, you are aware that each individual seedling has its own unique genotype. so no one is using the same genotype.

the environment it is grown in does have an effect on the bias, but not an earth shattering one... thats why Sativas still grow like Sativas even when hybridized and grown under an 18/6-12/12 (as Dj calls it) Indica cycle... the majority of the bias for one plant over the other comes from the human component, how good is the breeder at recognizing traits, which traits are being selected and ultimately which one is true breeding for those traits.

Sure if you had all of your other bases covered, were using large numbers, proper methods... and had the vision/liquid assets then setting up an extreme room where you can adjust all the perimeters photoperiod, the lights angle of impact, etc. etc. and use them to model any environment you could imagine would be one of the last little things (and most costly input) that can be done to get a slight edge over a standard indoor garden... though an outdoor cannabis hot spot would still be even better... gotta love California!

 

[purple_man]

yeh yeh, another brainjerking thread in the building

obviously to many folks talkin, to few doing... sounds as if plenty of folks gots their molecular biology lab equipment set up n calibrated, and debating about their findings... or is it just another brainjerker thread???

blessss
ps.: how about we start a sub-forum for: "theoretical breeding/wishful thinking"???

 

[xmobotx]

what's theoretical about these few previous pages? you kind of lost me purple man

 

[Weird]

http://www.cropscience.org.au/icsc2004/poster/3/2/2/1115_tokatlidisis.htm

Environmental effects on phenotypic expression are blunted in greenhouse compared to open field

Abstract

Two local dry bean populations were used in the study. A total of 432 widely spaced plants (80 x 80 cm) of each population were grown in the greenhouse. Another 500 widely spaced plants (100 x 100 cm) of each population were evaluated in the open field. In the greenhouse grain yield and pod number distributions of population A did not depart from normality. For both traits of population A in the open field, and for both traits of population B either in the greenhouse or in the open field, skewness and kurtosis were significant. Leftward transposition of mean due to positive skewness was accompanied by increased CV values. Although both populations had higher yield and pod number per plant in the open field than in the greenhouse, attributable to less competition, standard deviations increased in higher rates in the open field resulting in higher CV values. Compared to the greenhouse, in the open field CV values of yield and pod number were by 59 and 54% higher for population A, and by 42 and 20% higher for population B. Results revealed a stronger environmental impact on phenotypic expression in the open field, and therefore the greenhouse seemed to ensure conditions under which more objective and reliable selection could be applied.

Media summary

For grain yield and pod number per plant of two dry bean populations less environmental share of phenotypic variance was observed in greenhouse than in open field.

Key words

Genetic variance, Nil-competition, Honeycomb design
Introduction

A basic principle of plant breeding is the multiple-site evaluation and selection, so that breeders are able to cope with the genotype by environment interaction in their attempt to obtain adaptable and stable cultivars. A common practice is also the multiple-site evaluation and the single-site selection, whereas the application of the single-site evaluation and selection is not unusual, for example when any population or F2 are used as the initial material in a breeding project. In any case, breeders’ concern is the control of the environmental effects on phenotypic expression, so that the environmental share in the phenotypic variance decreases, and the chance of obtaining via phenotypes the more promising genotypes increases. Environmental parameters, such as soil heterogeneity, moisture and fertility, uneven depth of sowing, different seed size, as well as climatic fluctuations contribute to variance caused by other than genetic effects. Fasoulas and Fasoula (1995) suggested the honeycomb designs as an effective way to control undesired environmental effects (e.g., widely spaced plants exploit resources according to their genetic potential without being affected by neighbouring plants, and systematic plant arrangement with distances being the same for all plants permit selection at all levels of soil fertility overcoming the detrimental effects of soil heterogeneity). Coefficient of variation (CV) is the most widely used parameter to quantify variability among individual plants of a crop stand (Fasoula and Fasoula 1997; Janick 1999; Tollenaar and Wu 1999; Tokatlidis and Koutroubas 2004). CV represents two kinds of effects, as a consequence of genetic and environmental variance. Therefore, under comparable conditions any increase in CV values of a given entry, results from higher environmental effects. The purpose of the study was to evaluate how essentially different environmental conditions existing in greenhouse and open field affect the degree of environmental variance, in the aim to assess which of them represents more suitable conditions to apply selection in an objective and reliable way.
Methods

Two local dry bean populations were used in the study. These populations concern a famous for bean quality region, located in Western Macedonia, Greece. The first population (A), named by producers “plaki Prespon”, had been used mainly in the highlands until 1970, and thereafter it was replaced by the second population (B) named “Chrisoupoli”, which was assumed more adaptable to lowlands neighbouring “Prespa” lakes in the region. Experimentation was carried out in the Technological Education Institute Farm of Florina, Greece. A total of 432 plants of each population were grown in a greenhouse (sowing date 13 of March 2003), in nonreplicated (NR-0) honeycomb trials (Fasoulas and Fasoula 1995) with plants spaced 80 x 80 cm. Another two NR-0 trials were established on 3rd of May 2003 in the open air (a field adjoining to the greenhouse), each trial containing a total of about 500 plants spaced 100 x 100 cm. Although the 100 x 100 cm density was assumed to approach absence of competition, higher density in the greenhouse was preferred to give the opportunity of including higher total number of plants. Treatments like soil preparation, sowing depth, as well as weed, disease and insect control, irrigation, and fertilisation, were applied carefully to ensure as uniform as possible plant growing conditions. Plants were cut about 140 days after sowing and left to dry about 20 days. Mean grain yield and pod number per plant were calculated. For both traits CV values were also estimated. Skewness and kurtosis of yield and pod number distributions were used to estimate distribution departure from normality.
Results

Although population B had higher yield and pod number means than population A (Table 1), the two populations, more or less, responded the same to different environmental conditions (Fig. 1, 2). Both exhibited higher mean values in the open field than in the greenhouse, either for grain yield per plant or pod number per plant. This difference could be mainly attributed to less plant-to-plant interference for environmental inputs, due to less competition resulting from lower density in the open field. However, in the open field standard deviations increased in higher rates compared to means, and consequently the CV values increased (Fig. 1, 2). Distribution skewness and kurtosis of population A were not significant under the greenhouse conditions for both yield and pod number per plant. On the other hand, under the open field conditions, skewness and kurtosis were positive and significant, because of high number of plants accumulated on the left side of distribution, and accompanied by higher CV values (Fig. 1). Compared to the greenhouse, in the open field CV values of population A were by about 59 and 54% higher for yield and pod number, respectively. Higher CV values in the open field showed that environmental impact on phenotypic variance of population A was greater in the open field than in the greenhouse. The same impact was observed in case of population B. Although skewness and kurtosis of yield distribution were significant under either greenhouse or open field conditions (Table 1), CV increased by 42% in the open field (Fig. 2). Similarly, skewness and kurtosis of pod number distribution were significant under either greenhouse or open field conditions (Table 1), but CV increased by 20% in the open field (Fig. 2).

Table 1. Statistical parameters of the two populations (A, B) for grain yield and pod number including: number of plants harvested , mean value (), standard deviation (s.d.), skewness and kurtosis.



Population/Site


n




s.d.


skweness


kurtosis

Grain yield (g/plant)

A


Greenhouse


418


129.3


52.53


-0.084


-0.026


Open field


406


182.5


118.1


0.741 ***


0.583 **

B


Greenhouse


427


139.0


69.23


0.580 ***


0.430 *


Open field


431


195.0


138.0


0.361 **


-0.768 ***

Number of pods per plant

A


Greenhouse


418


70.72


26.36


-0.019


0.151


Open field


406


121.9


70.03


0.614 ***


0.315

B


Greenhouse


427


81.85


40.75


0.740 ***


0.872 ***


Open field


431


128.3


76.83


0.259 *


-0.415 *

* P<0.05, ** P<0.01, *** P<0.001

Although distribution of a population is expected to be normal, usually deviates from normality because of the environmental effects. As environmental effects become stronger, CV increases. The more the CV increases the more the distribution skews leftwards (Fasoula and Fasoula 1997). The fact that under lower density used in the open field both populations had greater means is an evidence that stronger plant-to-plant interference for use of environmental resources existed under higher density in the greenhouse. Consequently, in the greenhouse, even if one particular parameter of the environmental variance was stronger, total environmental variance was lower. Actually, under comparable conditions, less plant-to-plant interference for use of resources is expected to result in lower CV values (Fasoula and Fasoula 1997; Tollenaar and Wu 1999; Tokatlidis and koutroubas 2004). Kyriakou and Fasoulas (1985) compared the performance of a rye population under dense stand (15 x 15 cm) and under nil-competition (90 x 90 cm). Under nil-competition the grain yield distribution was normal, while under dense stand, although mean yield per plant was by 7.5 times lower (15 g), CV was by 1.6 times higher (53%), causing mean and mode of distribution to be transposed leftwards. Generally, there is a negative relationship between plant density and plant-to-plant uniformity, and therefore CV decreases as density decreases, until the plant-to-plant interference for use of resources becomes minimum (Fasoula and Fasoula 1997; Janick 1999). Therefore, increased environmental impact on the phenotypic expression of either grain yield per plant or pod number per plant was obvious in the open field. Higher environmental fluctuations under the open field conditions, such as air temperature and moisture, caused stronger environmental effects on phenotypic expression. Furthermore, plants in the open field were battered by hail on 25th of May, adding another environmental parameter in phenotypic variance. Results indicated that greenhouse conditions ensure better environmental control and seem to be more suitable to apply selection in the aim to identify the superior genotypes. Comparatively stronger environmental effects under the open field conditions lead in a more biased selection.

Figure 1. Yield (a) and pod number (b) distribution of population A in the greenhouse (continuous line) and in the open field (dotted line). CV=coefficient of variation.
Conclusion

Results indicated that for selection purposes in dry bean populations the density of 100 x 100 cm is preferable than that of 80 x 80 cm, when less plant-to-plant interference for use of resources is sought to eliminate the competition’s detrimental impact. Grain yield and pod number CV values, as well as their frequency distributions, evidenced that environmental effects on phenotypic expression are stronger in the open field. On the other hand, environmental confusing effects decreased under the greenhouse conditions. Therefore, in the greenhouse the risk of obtaining inferior genotypes is blunted and selection within a population may be applied in a more objective and reliable way.

Figure 2. Yield (a) and pod number (b) distribution of population B in the greenhouse (continuous line) and in the open field (dotted line). CV=coefficient of variation.
References

Fasoula DA and Fasoula VA (1997). Competitive ability and plant breeding. In Plant Breeding Reviews (Ed. J Janick) 14, 89-138.

Fasoulas AC and Fasoula VA (1995). Honeycomb selection designs. In Plant Breeding Reviews (Ed. J Janick) 13, 87-139.

Janick J (1999). Exploitation of heterosis: Uniformity and stability. In: The Genetics and Exploitation of Heterosis in Crops. pp. 319-333. Madison, WI. USA: ASA, CSSA, CSSA.

Kyriakou DT and Fasoulas AC (1985). Effects of competition and selection pressure on yield response in winter rye (Secale cereale L.). Euphytica, 34, 883-895.

Tokatlidis IS and Koutroubas SD (2004). A review of maize hybrids’ dependence on high plant populations and its implications for crop yield stability. Field Crops Research, in press.

Tollenaar M and Wu J (1999). Yield improvement in temperate maize is attributable to greater stress tolerance. Crop Science 39, 1597-1604.

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[xmobotx]

are you fucking kidding me?

so outdoors w/ wider spacing yields more than greenhouse w/ closer spacing

i hope they didnt pay too much for that study

 

[fadetoclear]

sorry ~i am agreeing w/ you where i point out the 'marketing' detail is where i attempt to simply add that while i agree i also feel there is a lot of misunderstanding perpetuated in the name of mystifying genetics and canna breeding

maybe some folks buy in to the myths and maybe some of the 'arguers' are knowingly perpetuating the myths

infinitesimal of course i remember those considerations

ok. i just wanted to make sure i wasn't coming off as facetious.

the whole "cannabis myth" as a marketing tool, while i will admit has been slightly effective, has done much to muddy the waters as far as actual genetic makeup and the experience of said "breeder".

i would have thrown blueberry in there as well but DJ has well documented his troubles with the thai strain he used and it's rampant tendency to intersex AND pass that intersex trait on to progeny. though, i always wondered why he continued on with a strain that he KNEW had issues with intersexing other than the fact that by that point he had invested SO much time. though i admit, blueberry was a great strain for it's time, it's flaws have by now been much better documented than anything i'm going to add other than to point out using plants with a tendency to hermaphrodite is always and obviously a BAD idea (almost above all else if seedless is the goal).

 

[Weird]

are you fucking kidding me?

so outdoors w/ wider spacing yields more than greenhouse w/ closer spacing

i hope they didnt pay too much for that study

They explain it is a matter of resource competition, what is so difficult to understand about that? and by what scientific grounds do you dispute that paper and what motivations would they have to skew results in that particular study?


have you ever run the same plants in various environments and based on that have different observations? if so please do tell

 

[Infinitesimal]

AGAIN, growing the same individuals from a variety in multiple locations does nothing but show the strains level of prepotency for its selected traits... meaning... does it express its trait across a wide spectrum of environments and conditions or does it need a very specific environment to express any given trait?... which is important but not NEAR as important as ensuring that each individual contains the gene responsible for that expression in the first place...
because without using homozygous individuals as the parent stock how can you be sure that the lack of expression in some individuals is from an environmental factor, as opposed to the result of using heterozygous parents?

you cannot compare the breeding of food crops to drug trait cannabis... if you allow (most) food crops to breed naturally they remain that type of food... if you put drug cannabis in to an open field and let it breed naturally - regardless of the environment- with open pollination/natural selection techniques drug cannabis goes feral and reverts back into hemp fiber producing cannabis after a number of generations... god nor mother nature created the weed we smoke, it is 100% man made through selecting and breeding of the genes responsible for THC production into a homozygous condition, which does not readily happen in nature.

my point is, the environment plays a significant but relatively small role in the success of a breeding project... when compared to making multiple (full sib or pedigreed) crosses creating divergent "families" within the same lines then Identifying which families are desirable culling the undesirable families and using the homozygous individuals responsible for the desirable families to further the line into the next generation.

 

[Infinitesimal]

have you ever run the same plants in various environments and based on that have different observations? if so please do tell

have you? if so please do tell what the differences are in that plants progeny... since that IS what we are discussing... breeding, how combining genetics effects the progeny... not how changing the environment effects your clone.

so I ask you... what observations have you made on the differences in progeny as a result of mating the same pair of parents in differing environments?... since that actually WOULD be relevant to the discussion... instead of the fact that you get better traits from certain plants when grown in certain environments (woohoo big deal, everyone knows that )

 

[xmobotx]

They explain it is a matter of resource competition, what is so difficult to understand about that? and by what scientific grounds do you dispute that paper and what motivations would they have to skew results in that particular study?


have you ever run the same plants in various environments and based on that have different observations? if so please do tell

dude! come on! seriously? i dispute nothing about that study ~my response is, "duh"

for the love of god man

NOBODY is refuting g+e=p here

we are talking about g not e

e barely fucking matters because most of these guys grow in a controlled environ ~if you are talking about outdoors it is going to be different for every single person on the forum so i guess they better all do their own breeding if they want to do outdoors

next are you going to tell us brand whatever won't grow in an oven set to '500' w/ the light off?

why cant you understand what i am saying here? my posts are typically like 3 lines and you must not even read them

yet i m supposed to read 150 lines of cut & paste to tell me something i already know?

 

[Biosynthesis]

GONG