Association between allelic variation at theWaxylocus and starch physicochemical properties using single-segment substitution lines in rice (Oryza sativaL.)

The Waxy locus is the major locus controlling AM synthesis in rice endosperm. To date, based on amylose phenotypes and four nucleotide polymorphisms in the Waxy gene, five common Waxy alleles, wx, Wxt, Wxg1, Wxg2, and Wxg3, had been identified. A better understanding of how the Waxy allelic variation controls rice starch properties is important for grain quality improvement. In this study, genetic effects of different Waxy alleles on rice starch properties were obtained by use of a set of single-segment substitution lines harboring five different Waxy alleles. The five Waxy alleles showed a wide variation in gel consistency (GC), gelatinization temperature (GT), and pasting viscosity parameters. The relative effects of the five Waxy alleles on GC values was wx>Wxg3>Wxt>Wxg1>Wxg2, and the trend in the GT values was wx