Molecular Plant Available online 8 June 2019 https://doi.org/10.1016/j.molp.2019.05.011

ChangquanZhang, JihuiZhu, ShengjieChen, XiaoleiFan, QianfengLi, YanLu, MinWang , HengxiuYu, ChuandengYi, ShuzhuTang, MinghongGu and QiaoquanLiu

Abstract

In rice grains, the Waxy (Wx) gene is responsible for the synthesis of amylose, the most important determinant for eating and cooking quality. Up to now, several Wx alleles have been elucidated on their effects of amylose content as well as the taste of cooked rice. However, the relationships between artificial selection and the evolution as well as distribution of various Wx alleles remain unclear. Herein, we report the cloning of the ancestral allele Wxlv of the Wx locus, which dramatically affects the mouthfeel of rice grains by modulating the size of amylose molecules. We demonstrated that Wxlv originated directly from wild rice, and the three major Wx alleles in cultivated rice (Wxb, Wxa, and Wxin) differentiated after the substitution of one base pair at the functional sites. These data indicate that the Wxlv allele played an important role in artificial selection and domestication. The findings also shed light on the evolution of various Wx alleles, which have greatly contributed to improving the eating and cooking quality of rice.

Keywords  Oryza sativa; Waxy; eating and cooking quality; allelic variation; artificial selection

https://www.sciencedirect.com/science/article/pii/S1674205219301972