Identification and Characterization of Waxy Bread Wheat Carrying a Novel <em>Wx-B1 </em>Allele

Abstract

Starch content in wheat is an important characteristic for various purposes. Starch is composed of two components known as amylose and amylopectin, and the proportion between these two components plays a crucial role in determining the properties and structure of starch. One of the key genes involved in starch biosynthesis in wheat is granule bound starch synthase I (GBSSI), also known as the waxy protein, which synthesizes amylose in the endosperm. A mutant cultivar, named Gunji-3, was created by crossing the waxy type wheat (Shinmichal 1) with the wild type bread wheat (Keumkang). When comparing the Wx-B1 allele of the waxy protein gene in Gunji-3 with that of the waxy type wheat, there were 12 SNPs and one deletion difference. Additionally, when comparing amino acid sequences with Wx-B1 alleles, differences at two positions are found, indicating that the mutant carries new Wx-B1 allele which is named as Wx-B1o. In terms of the physicochemical properties of Gunji-3 starch, it had a lower amylose content than the parental wheat varieties and showed higher protein content and greater swelling power. These newly introduced waxy type wheat could provide important basis not only for understanding the starch characteristics of wheat but also for various breeding programs.