Segregation Analysis for Inheritance of Protein Related Traits in Soybean [Glycine max(L.) Merr.]

The quality and processing property of soy protein depend on its constitution of components and subunit groups,as well as their related traits.The recombinant inbred line population(RIKY) derived from Kefeng 1×Nannong 1138-2 and backcross inbred derived line population(BIEX) derived from(Essex×ZDD2315) ×ZDD2315 were tested for their 16 traits related to protein components and their subunit groups,including protein content,protein plus fat content,11S,7S,11S/7S ratio,four 11S subunit groups and six 7S subunit groups,by using Kjeltec,Soxtec and SDS-PAGE analysis.The data obtained were analyzed for the inheritance of the 16 traits by using segregation analysis based on mixed major gene plus polygene inheritance model.The results showed that there existed transgressive segregations in all the traits,which indicated the mutual complement among loci between the parents.One major gene plus polygene mixed model was detected for protein content in both populations with major gene heritability(MGH) 31.3-40.9% and polygene heritability(PGH) 37.2-53.7%;three major genes plus polygene model for protein plus fat content with MGH 59.9-66.6% and PGH 23.2-27.9%;two to three major genes plus polygene model for oil content with MGH 48.6-71.7% and PGH 4.2-29.7%.Three major genes plus polygene inheritance model was detected for 11S protein content with MGH 14.3-60.7% and PGH 17.0-50.7%;three major genes plus polygene model for 7S protein content with MGH 34.5-44.1% and PGH 21.5-45.1%;two major genes plus polygene model for 11S/7S ratio with MGH 56.6-74.8% and PGH 10.1-20.1%.Two to three major gene plus polygene,two major genes plus polygene,two major genes plus polygene and two to three major genes plus polygene inheritance models were detected for 11S-1 through 11S-4,respectively;one to two major genes plus polygene,two major genes plus polygene,two to three major genes plus polygene,three major genes plus polygene,one to two major genes plus polygene and two major genes plus polygene inheritance models were detected for 7S-1 through 7S-6,respectively.All of 16 traits are controlled by both major genes and minor genes.Among them,ten traits are controlled by same numbers of major genes in both populations and for the other six traits there is one major gene difference between the two populations.Thus,between the two populations,for each trait,the inheritance model is mainly similar in number of major genes while somewhat different in gene effect for those with same major gene numbers.Therefore,plant breeders have to pyramid both major genes and polygenes in breeding for protein content and related quality traits.