Characrerizing the Sequences of <i>Kr</i> Gene in Common Wheat

Abstract

The incompatibility of distant hybridization in wheat has been known to be controlled by the Kr gene. In order to figure out the characteristics of the Kr gene in different genotypes of wheat, the six genotype germplasms selected from the Chinese wheat micro-core collection, called Mazhamai, Xiaobaimang, Tuokexunyihao, Chinese spring, Yangmai, and Zhengmai9023, were employed to be experimental materials for identifying the characteristic of the Kr genes by means of the homology cloning approach. The results showed that the three of six genotypes could amplify a fragment of Kr gene with 414 bp in length. The sequences among three cloned fragments shared 99.8% homology except two sites with SNP differences. Blast analysis indicated that the cloned sequences of partial Kr genes have 85% homology with the S-locus receptor kinase gene in the same regions. Thus, we preliminarily speculated the Kr gene might possess similar functions as the gene conferring self-incompatibility in plant,which possibly facilitated cellulae mastoideaes to accumulate calloses in chapitersand affected the competitive ability of exogenous pollens eventually resulting in the incompatibility of distant hybridization in wheat.