Validation of CAPS marker WR003 for the leaf rust resistance gene Lr1 and the molecular evolution of Lr1 in wheat

The wheat leaf rust resistance gene Lr1 encodes a typical coiled-coil nucleotide-binding site leucine-rich repeat (CC-NBS-LRR) of protein containing 1 344 amino acids. WR003, cleaved amplified polymorphic sequence (CAPS) marker is derived from the LRR regions Lr1. In this study, worldwide collection 120 Aegilops tauschii accessions and 282 hexaploid varieties was screened for alleles using specificity WR003 confirmed by pathogenicity tests genotype analysis. alignment phylogenetic tree analysis 38 haplotypes provided further view molecular evolution results showed that there were very few polymorphisms between Ae. with same phenotype. mainly different lines, rather than ploidy levels. These indicate originated differentiated into resistant susceptible genotypes before its introgression wheat. Therefore, it likely has at least two major variants disease susceptibility, except certain point mutations, conversions genetic re-combinations occurred during domestication.