“…So far, MAS has been used in rice mainly to introgress the favourable alleles of genes involved in resistance to diseases and pests. In India and the Philippines, bacterial blight (BB) resistance alleles of genes Xa4, xa5, xa13 and Xa21 have been successfully introgressed into hybrid rice KMR3, PRR78, IR58025B and Pusa 6B (Shanti et al, 2010). Different combinations of favourable alleles of either two or three resistance genes have also been incorporated into elite varieties using MAS, providing high level of resistance to ten highly virulent bacterial isolates (Singh et al, 2001;Leung et al, 2004;Agarcio et al, 2007;Borines et al, 2008;Collard and Mackill, 2008;Perez et al, 2008;Sundaram et al, 2008Sundaram et al, , 2009Vera Cruz et al, 2009).…”