Introgression of Xa7 for Bacterial Blight Resistance to Restorer Line for Development of Two-line Hybrid

Abstract

   Two-line hybrid rice variety LC212 is valuable variety with high yielding potential, short growing duration, widely adaptation to environment but susceptible to Bacterial Leaf Blight (BLB). Backcross breeding method was conducted for transferring Xa7 gene to restorer R212 which is male of hybrid rice variety LC212. The plants which have phenotype similar of R212, high resistance to three typical BLB races, carrying homogenous Xa7 gene of BC2 and BC3 generation were selected by Pedigree selection. The selected plants were inoculated, similar phenotype was selected and MAS technicque were used to identify Xa7 gene. The 25 lines R212BB of BC2F4 and the 8 lines R212BB of BC3F3 were selected. They are using for father step breeding of R212 restorer resistance to BLB as announced improved rice lines LC212.