Improvement of rice cultivar for bacterial blight disease through marker assisted breeding approach

Abstract

The present investigation was undertaken with the objective to develop high yielding, fine grain rice varieties possessing broad spectrum durable resistance by transferring bacterial leaf blight (BLB) resistant genes viz., xa13 and Xa21 from Improved Pusa Basmati 1. A popular high yielding and fine grain rice variety, HUBR 2-1 (Malviya Dhan 2-1), susceptible to BLB and Improved Pusa Basmati 1 carrying resistant genes for BLB (xa13 & Xa21 genes) were selected as parents for crossing. Improved Pusa Basmati 1 was verified for the presence of target genes by using gene linked primers viz., xa13 promotor and pTA 248. The cross viz., HUBR 2-1 x Improved Pusa Basmati 1 was undertaken during Kharif 2011 and F1 progenies were confirmed during rabi 2011. The F1 plants confirmed as true hybrids for both the genes were advanced to the F2 generation and foreground selection was done using gene linked markers. Genetic analysis in the F2 population confirmed that the genes (xa13 & Xa21) governing BLB resistance followed Mendelian inheritance. The phenotypic data analysis revealed that the plants carrying two resistance gene combinations (xa13xa13 Xa21Xa21, xa13xa13Xa21xa21) showed BLB resistance (0-3 scale), while the gene combinations viz., Xa13Xa13Xa21Xa21, Xa13Xa13Xa21xa21 and Xa13xa13Xa21Xa21, Xa13xa13Xa21xa21 showed BLB resistance (5-30).