Ecological Dfference In Northeast Three Provinces In China And Genetic Effects Analysis For Quality Traits In Soybean

Ecological difference of protein and oil content in northeast three provinces in China was analyzed by the experiment of 5 soybean (G. max Merill) varieties planted in 11 locations during 3 years and the quality traits of 97 soybean varieties from the northeast three provinces planted 50 thounsd per year, and quality regionatization was conducted according to the weighted average of genotypic and locations effects. At the same time, analysis of embryo, cytoplasm and maternal effects and genotype X environment interaction effects for quality traits of soybean (G. max Merill) seeds by using a general genetic model for quantitative traits of seeds (Zhu, 1997) with parents, F₁ and F₂ of 10 crosses from a diallel mating design of 5 parents planted in the field in 2003 and 2004. The main results were as following:1. There were highly significance among years effect, locations effect, years× locations interaction effect, genotype effect, genotype × years interaction effect, genotype × locations interaction effect, genotype × years × locations interaction effect for protein and oil content. In northeast in China, the location effect of protein and oil content decreased gradually from south to north..2. The difference of protein and oil content of varieties in different location reached highly significance. The protein content of soybean varieties changed low and oil content changed high from south to north in northeast three province in China.3. According to the cluster analysis of weighted average of genotype and locations effects of protein and oil content, environment condition, of different location and administrative completence, the soybean production region in northeast three province was devided into five districts: north high-oil districts ( â… -1); middle western-northern protein-oil balance district (â…¡ -1); middle high-oil districts ( â… -2); middle southern protein-oil balance district (â…¡ -2); southern high-protein districts (â…¢) .4. The results of two year-data indicated that the genetic main effects were larger than interaction effects for protein content, oil content, threonine, serine, alanine, phenylalanineand tryptophan. The interaction effects were larger than genetic main effects for total content of protein and oil, aspartic acid, glutamic, glycine, cysteine, valine, methionine, isoleucine. leucine, lysine, histidine, arginine, proline, palmitic, stearic and linolenic. The interaction effects were similar to genetic main effects for tyrsine, oleic and linolenic. Quality traits of soybean were controlled by embryo, cytoplasm and maternal genetic system. Among all kinds of genetic main effects, the embryo effects were largest for aspartic acid, serine, lysine, tryptophan, palmitic, stearic and linoleic, cytoplasm effects were largest for protein content, oil content, glutamic, valine, isoleucine, leucine, tyrsine, phenylalanine, histidine, arginine, proline, oleic and linolenic, the maternal effects were largest for total content of protein and oil , glycine and methionine.Among all kinds of interaction effects, the embryo interaction effects were the largest for protein content, oil content, cysteine content, tryptophan content and atty acids, the maternal interaction effects were the largest for total content of protein and oil, aspartic acid content, threonine content, serine content, glutamic acid content, glycine content, alanine content, valine content, methionine content, isoleucine content, tyrosine content, phenylalanine content, lysine and arginine content, the embryo interaction effects were equal to maternal interaction effects for leucine content, histidine content and praline content. The sum of additive and additive X environment effects were larger than that of dominance and dominance X environment effects for protein content, oil content, total content of protein and oil, glutamic content, cysteine content, isoluecine content, luecine content, histidine content, proline content, tryptophan content and linolenic content, but not for the other quality traits.5. The heritabilities (including general heritability and interaction heritability) of soybean quality traits ranged from 9.8% to 66.1 %. With higher heritabilities (over 30%), protein content, oil content, glutamic content, cysteine content, valine content, isoluecine content, luecine content, tyrsine content, phenylalanine content, histidine content, arginine content, proline content and linolenic content could get better efficiency of improvement. Among the quality traits of soybean seeds, the general heritabilities were the main parts of heritabilities for protein content, oil content, aspartic content, threonine content, serine content, glutamic content, glycine content, alanine content, cysteine content, valine content, tyrsine content, phenylalanine content, arginine content, tryptophan content, palmitic content and oleic content, but the interaction were more important for total content of protein and oil, methionine content, isoluecine content, luecine content, lysine content, histidine content, arginine content, stearic content, linoleic content andlinolenic content. For the general heritability, maternal and cytoplasm heritabilities were the main components for protein content, oil content, glutamic acid content, glycine content, cysteine content, valine content, methionnine content, isoluecine content, luecine content, tyrsine content, phenylalanine content, lysine content, histidine content, arginine content, proline content, palmitic content, oleic content and linolenic content and these traits could be improved through the performance of these traits in the plant, while the main heritability components of aspartic acid content, threonine content, serine content, alanine content and tryptophan content were embryo general heritabilities and it could be better to select single-seed for these quality traits in soybean quality breeding. It was showed by the interaction heritabilities that embryo interaction heritabilities were more important for protein content, oil content, glycine content, cysteine content, methionine content, isoluecine content, luecine content, lysine content, histidine content, arginine content, proline content, oleic content and linolenic content, while maternal interaction heritabilities were more important for total content of protein and oil, aspartic acid content, threonine content, serine content, alanine content, tyrsine content, phenylalanine content, tryptophan content and linoleic content.6. It was indicated by the result of heritabilities that the estimates of selection response (including general response and interaction response) were 0.85%-18.65% and the better improvement could be obtained through suitable selection for most of soybean quality traits. The general response were larger than the interaction responses for protein content, oil content, aspartic acid content, threonine content, serine content, glutamic acid content, glycine content, alanine content, cysteine content, tyrosine content, phenylalanine content, arginene content, tryptophan content, palmitic content, oleic content and linolenic, but not for total content of protein and oil, methionine content, isoluecine content, leucine content, lysine content, histidine content, stearic content and linoleic. Among selection response components, maternal and cytoplasm general responses and/or interaction responses were more important for protein content, oil content, total content of protein and oil, aspartic acid content, glutamic acid content, valine content, isoluecine content, luecine content, phenylalanine content, arginine content, tryptophan content, palmitic content, stearic content, oleic content and linoleic and it was better to improve these traits by the method of single-plant selection. The main selection response components were of embryo general response and/or interaction response for threonine content, serine content, alanine content, cysteine content, methionine content, lysine content, histidine content and linolenic content and it wasbetter to improve these traits by the method of single-seed selection. The selection responses relative to embryo were almost equal to those relative to maternal and cytoplasm genes for glycine content and praline content, so that it was better to improve these two quality traits by using the methods of single-plant selection with single-seed selection in soybean breeding.7. The negative phenotypic and genetic correlation between protein content and oil content, oil content and linolenic content, palmitic content and stearic content, palmitic content and linoleic content, oleic content and linolenic content and the positive phenotypic and genetic correlation between palmitic content and oleic content, stearic content and linoleic, oleic and linoleic content, linoleic content and linolenic content were found significant. It were difficult to improve simultaneously protein content and oil content, oil content and linolenic content, palmitic content and stearic content, palmitic content and linoleic content, or to improve linoleic and decrease linolenic content at the same time, while it was expect to improve oil content and oleic content and decrease linolenic content simultaneously or to improve palmitic content and oleic content, stearic content and linoleic, oleic and linoleic content in the same step. The genetic correlations among other paired traits were all not significant. The analysis of genetic correlation components including embryo, cytoplasm and maternal correlation and GE interaction correlations showed that there were closely relationships for most of genetic effects in the paired traits and these relationship could be used in indirect selection of soybean quality breeding especially for the paired traits with additive and/or cytoplasm correlations. The relationship of dominance and /or cytoplasm effects could also be used in hybrid soybean breeding for simultaneously improving the paired quality traits. The genetic main correlations constituted a major part of relationship between protein content and praline content, therefore the relationships for these paired quality traits were stable in different environments, while main part of relationship among other paired quality traits were GE interaction correlations. For the paired traits which mainly affected by maternal additive and maternal additive interaction correlation and/or cytoplasm and cytoplasm interaction correlation, the better improvement effects could be obtained by indirect selection according to the performance of paired soybean quality traits in the maternal plant. While the paired traits which mainly affected by embryo additive and additive interaction correlation, it was better to use the method of single-seed selection for simultaneously improving the paired quality traits.8. The results of heterosis analysis for 10 hybrid crosses in soybean indicated that the total heterosis for oil content, aspartic acid content, threonine content, serine content, glutamicacidcontent, alanine content, cysteine content, valine content, luecine content, tyrosine content, phenylalanine content, lysine content, histidine content, arginine content, stearic content andoleic content were positive and these traits could be increased by the heterosis, while the total heterosis for protein content, total content of protein and oil, glycine content, methionine content, isoluecine content, praline content, tryptophan content, palmitic content, linoleic content and linolenic content were negative and the heterosis can reduce these quality traits. The interaction heterosis for most quality traits were not at the same direction for both environments. It was also indicated by the results of heterosis components analysis that different heterosis of different components could affect he F2 soybean quality traits lonely or jointly.