Development of Drought Tolerant, Blast and Bacterial Leaf Blight Resistant Rice Improved Lines Through Marker-Assisted selection

Abstract

Rice is an important staple food crop and its yield could be influenced by biotic and abiotic conditions. The research was conducted to identify the polymorphic markers at the target region (parental survey) and were also used to select improved lines with multiple traits of resistance to diseases and drought tolerance. Three varieties were used, Putra-1 with high yielding & resistant to blast, MR219-PL-137 with tolerant to drought.  IRBB60 had resistance to bacterial leaf blight (BLB) disease. They were crossed to a recipient parent (Putra-1). Three crossing methods (single, double and three-way) were utilized. Result shows primers indicated clear polymorphism among the three parents.  The homozygous resistant plants similar to recipient parent in F2 were selected using the polymorphic and linked markers (RM6836, RM8225) and (RM520, RM511 and RM1261) for three-way cross and reciprocal, respectively, with MR219-PL-137 drought tolerant line as the recipient parent. Nine improved rice lines had high yield, blast, BLB disease resistance & drought tolerance traits. Two improved lines had blast resistance and drought tolerance traits (PD14, PD15), while seven had blast, bacteria leaf blight resistance and drought tolerance traits (PDB3, PBD1, PBD3, DPB7, DPB12, DPB13, DPB20).