Heterosis And Nutrition Composition Analysis Of Dominant Low Gossypol Hybrid Cotton

Dominant low gossypol cotton is a glandless character controlled by single dominant gene, it has more advantages in practice than those controlled by double recessive gene1) Easily to identify in hybrid separation group, can reduce sample capability of some separation group, short the generation number to translate to different background, speed up breeding progress.2) can prevent seed quality pollution due to the recessive glandless cotton and glandular cotton natural crossing in field production.3)can be used as a mark in hybrid breeding——Using dominant glandless lines as male parents, if the F1generation glandless,they must be true hybrids,if not,they must be false.This experiment used dominant low gossypol hybrid cotton as materials, which were bred by using single dominant low gossypol cotton as male parent.We had analysed their yied heterosis, disease resistance，cotton leaves and cottonseeds nutrition constituent, the gossypol content、protein conten、amino acid content and fat content, and constructed a SSR fingerprint. The research results showed as following:1、Compared Suza501and Suza502with the widespread variety Suza6, analyzed the mid-parent advantage and competitive advantage of the two low gossypol hybrid cotton. The results showed the two dominant low gossypol hybrid cotton expressed obvious advantages in mid-parent heterosis and competitive advantage. Both suza501and suza502showed positive mid-parent advantage. Suza501yields of unginned and ginned cotton were increased12.69%and12.57%respectively than its parents; Suza502increased21.41%and18.54%respectively. Suza501showed a negative competitive advantage, which yields of unginned and ginned cotton decreased1.02%、4.72%respectively. Suza502showed a positive competitive advantage which yields of unginned and ginned cotton increased3.41%and0.11%respectively than Suza6. Tested two dominant low gossypol combinations suza501、suza502pest and disease resistance properties.The results showed that suza501、suza502had verticilliu wilt resistance and insect resistance.Suza501and suza502verticillium wilt relative disease indexes were25.9and24.7respectively.average resistance values to cotton bollworm were2.50and3.42respectively.2、Gossypol content in cottonseeds had significant differences in different species.Even in the same variety, gossypol content also had significant difference before and after oil.After deoil, the gossypol content in Suza501seeds and Suza502seeds were30.42mg/kg and39.34mg/kg respectively, the F2generations were373.22mg/kg and367.92mg/kg respectively, all in safety index range for animal feed. Showed huge potential in forage value.3、Cottonseeds contained rich protein, the protein in gland cottonseeds were higher than in glandless. Fat content in cottonseeds were high, in the range of27%-29%.Tested amino acid content in Suza501seeds and Suza502seeds and their F2genaration. There were18amino acids in cottonseeds and contained7essential amino acids, they were valine、isoleucine、phenylalanine、leucine、threonine、methionine and lysine. The glutamic acid content was8.361mg/100g on average, was the highest in cottonseeds. In addition, half essential amino acid——arginine and histidine content were also high, in an average of5.2g/100g and1.64g/100g respectively. The amino acid in glandless cottonseeds and gland cottonseeds had no obvious difference, as well as the amino acid in F1、F2generation cottonseeds.4、Gossypol content in branches and leaves were low,they were all lower than safety standards400mg/kg.Protein in leaves were rich.In the later stage of cotton growth, gossypol content in branches and leaves displayed a decreases trend,and protein content in leaves showed a slowly rise trend.5、In order to prevent some illegal businessmen from posing conventional dominant low gossypol cotton as hybrid dominant low gossypol cotton, a fingerprint using SSR molecular markers had been constructed. By the primer MH0454, it’s easily to separate dominant low gossypol cotton from their parents, and conventional dominant low gossypol cotton plants.