Conventional breeding involves time taking procedure for pyramiding of genes and screening of crops for the same. Double haploid (DH) production can reduce the time of production of resistant crops in less time period. Twenty one plants that survived after the hardening procedure were screened phenotypically and molecularly for BB resistant genes. When the DH plants were infected with Xoo, they showed four plants (nineteen percent) showed resistant reaction, twelve plants (fifty seven percent) showed moderately resistant reaction, four plants (nineteen percent) were moderately susceptible reaction and one plant (five percent) showed susceptible reaction. The primer pairs, Xa21 pTA248 and xa13- prom showed good polymorphism between the resistant and susceptible genotypes with an amplicon size of 1000bp and 500bp in the resistant genotypes of Xa21 and xa13 and 650bp and 250bp amplicon in the susceptible genotypes respectively, while heterozygous individuals amplified both the two fragments Parent PAU148 (PA) is heterozygous as they amplified both the strands. Parent ranbir basmati (RB) has only recessive genes for both Xa21 and xa13 genes. Except for plant number 8 and 21that are susceptible, all the plants have dominant gene for Xa21 and are homozygous. Except for plant number 8 that is heterozygous and plant number 21that is susceptible, all the plants have dominant gene for xa13 and are homozygous. | In-vitro screening and molecular characterization of the double haploids for the bacterial blight resistance genes Xa21 and Xa13
