Molecular Profiling of Yield-Associated Genes/QTLs in Advanced Rice Breeding Lines (Oryza sativa L.)

Abstract

An investigation was conducted at Indian Institute of Rice Research (IIRR) farm located at Rajendranagar, Hyderabad. The experimental field was laid in RBD design using 30 advanced Breeding Lines ABL (SP-02, SP-03, SP-08, SP-13, SP-25, SP-34, SP-37, SP-55, SP-57, SP-61, SP-63, SP-69, SP-70, SP-72, SP-75, SP-80, SP-351, SP-352, SP-353, SP-354, SP-355, SP-356, SP-357, SP-358, SP-359, SP-360, NDR-359, IR-64 and JAYA), including one check variety BPT-5204.BPT-5204 used as quality check. For molecular characterization of advanced breeding lines seven genes (Gn1&Gn2for grain number; SCM2 and SCM3 for strong culm; Gs3for grain size; Gw5for grain weight; Spl14for spikelet length) and three QTLs (Yld12.1, Yld2.1 and Yld4.1for yield) were used. Upon genotyping, 30 advanced breeding lines, only one advanced breeding line SP-08 showed the presence of seven yield contributing genes/QTLs (Gn1, Gn2, SCM2, SCM3, Gw5, Yld12.1, Yld2.1) indicating presence of high potential for yield. Two advanced breeding lines showed the presence of six yield contributing genes/QTLs, they are SP-69 (Gn1, Gn2, SCM3, Gw5, Spl14, Yld2.1) and SP-70 (Gn1, SCM3, Gw5, Gs3, Yld2.1, Yld12.1). Whereas four advanced breeding lines showed the presence of five yield contributing genes. They are SP-37 (Gn2, SCM3, Gw5, Yld12.1, Yld2.1), SP-55 (Gn2, SCM2, SCM3, Gw5, Yld2.1), SP-75 (Gn1, Gn2, SCM3, Gw5, Yld12.1) and SP-61 (Gn1, Gn2, SCM2, Gw5, Yld2.1). The morphological and physiological parameters of advanced breeding lines were correlated with the molecular analysis. SP-08 showed better morphological and physiological parameters like number of tillers, LAD, LAI, CGR, NAR, and also showed the presence of seven (Gn1, Gn2, SCM2, SCM3, Gw5, Yld12.1 and Yld2.1) yield contributing genes/QTLs. Genotype, SP-70 showed better in several physiological parameters photosynthetic rate, SPAD meter readings, dry matter accumulation, and also contain six (Gn1, SCM3, Gw5, Gs3, Yld2.1 and Yld12.1) genes/QTLs. Genotype, SP-69 higher panicle length and also contain six corresponding genes governing (Gn1, Gn2, SCM3, Gw5, Spl14 and Yld2.1) genes/QTLs. Two advanced breeding lines namely SP-08, SP-70 can be further probed thoroughly for further increasing yield and yield attribute.