Effects of Wx and Its Interaction With SSIII-2 on Rice Eating and Cooking Qualities

The gene encodes a granule-bound starch synthase (GBSS) and plays a key role in determining rice eating and cooking qualities (ECQs). SSIII-2 (SSIIIa), a member of the soluble starch synthases, is responsible for the synthesis of long chains of amylopectin. To investigate the effects of and its interaction with on grain ECQs, a population from a hybrid combination was established as a research material. The genotypes of and the single nucleotide polymorphisms (SNPs) on intron1, exon6, and exon10 of , and the physicochemical indicators and rapid visco analyzer (RVA) profile characteristics were analyzed. The results revealed various effects of on rice quality under different backgrounds of alleles. There was no obvious difference between different alleles under the same background of , whereas there was a significant diversity under the same background of . had a dominant epistasis to because the effect of was masked by the massive synthesis of GBSS under . The apparent amylose content (AAC) was mainly controlled by the In1G/T SNP, and rice gel consistency (GC) was regulated by the Ex10C/T SNP. The combined effects of three SNPs had a significant influence on all ECQs and RVA profile parameters, except for gelatinization temperature. In1T-Ex6A-Ex10C and In1T-Ex6A-Ex10T were classified as being low AAC type. TT-AA-CC and TT-AA-TT had a low AAC and a soft GC. The combined effects of different SNPs of are very important for rice quality breeding.