Parental polymorphism survey using genome-wide SSR markers for brown planthopper resistance in rice

For introgressing Brown planthopper (BPH) resistance into a rice variety using marker assisted selection, study of parental polymorphism between the donor and recipient parents is a pre-requisite step. Unless the parents are polymorphic for the BPH reaction, further selection of plants carrying the traits may not be possible. Thus, the present investigation was conducted to analyze the polymorphism of two BPH resistant donors (M229, 10-3) and a recipient (Telangana Sona) parent using SSR markers. A total of 494 random microsatellite markers evenly distributed across 12 chromosomes were used for the polymorphic survey. Among these, 87 markers were found polymorphic between M229 and Telangana Sona, while 93 were polymorphic between 10-3 and Telangana Sona by producing distinct reproducible amplification patterns. The highest percentage of polymorphism was observed on chromosome 12 (30.59%) for Telangana Sona and M229, while chromosome 1 (30.61%) recorded the highest polymorphism percentage for Telangana Sona and 10-3 indicating that these chromosomes are useful in studying the variation between the parents. Accordingly, the maximum number of polymorphic markers were obtained on chromosome 6 for the parents of both the crosses. The identified polymorphic markers across the 12 chromosomes will be useful in subsequent linkage map construction along with mapping of QTLs associated with BPH resistance.