Detection of Bacterial Blight Resistance Genes Xa7, Xa21in Male lines of Rice by Molecular Markers

Abstract

Three male lines 9311BB, D42BB, R308BB were developed by crossing parental lines 9311, D42, R308 with the near-isogenic lines of rice carrying Xa7 and Xa21resistance genes using backcross breeding program. The markers pTA248, RM5509 linked tightly with Xa21 gene, Xa7gene, respectively were used to detect bacterial blight resistance genes. The result showed that 90% individuals of R308BB were homozygous for Xa21gene and 10% individuals were heterozygous while the D42BB have 10% heterozygote for Xa21 gene and 100% individuals of 9311BB were homozygous for Xa7gene. This result coincides well with the artificially infected result on BC3F1of 9311BB and R308BB except for D42BB. The research demonstrated that molecular marker is a useful tool for the detection of the target genes