Morpho-Phenological and Molecular Traits for Yield-Associated Genes/QTLs in Advanced Rice Breeding Lines (Oryza sativaL.)

An investigation was conducted at the Indian Institute of Rice Research (IIRR) farm located at Rajendranagar, Hyderabad. The experimental ield was laid out in an RBD design using 30 advanced breeding lines. BPT-5204 is used as a quality check. The experimental ield was laid in RBD replicated thrice with 30 high yielding rice genotypes which includes 26 advanced breeding lines (ABL) (SP-351, SP-352, SP-353, SP-354, SP-355, SP-356, SP-357, SP-358, SP-359, SP- 360, SP-70, SP-72, SP-63, SP-61, SP-69, SP-55, SP80, SP-25, SP-13, SP-03, SP-02, SP-34, SP-37, SP-08, SP-75 and SP-57) and four checks(NDR-359, BPT-5204, IR-64, Jaya). Morphological parameters of plant height among genotypes ranged from 92 to 131cm. Genotype, SP-70 (126 cm), showed maximum plant height and was followed by SP-355 (124 cm), compared to BPT-5204 (98 cm). Mean plant height increased by 44.3% from active tillering to panicle initiation stage and then by 28.4% from PI to physiological maturity. A higher number of tillers per plant was observed in SP-08 and SP-70 (23) compared to check BPT-5204 (18). Among the duration groups, the short duration (116 to 122 days) lines were SP-08, SP-72, SP-70, and SP-69. The medium duration (125 to 133 days) lines, SP-351, SP-353, SP-355, SP-357, SP- 80, and SP-25, and long duration (140 to 148 days) lines, SP-02, SP-03, and SP-37 found superior in terms of grain yield as compared to their respective check varieties. Two advanced breeding lines, namely SP-08, SP-70, can be further probed thoroughly for further increasing yield and yield attributes. The morphological and physiological parameters of advanced breeding lines were correlated with the molecular analysis. SP-08 showed better morpho-phenological parameters like the number of tillers and also showed the presence of seven (Gn1, Gn2, 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 contains six (Gn1, Yld2.1, and Yld12.1) genes/QTLs. Genotype, SP-69 higher panicle length and also contains six corresponding genes governing (Gn1, Gn2, and Yld2.1) genes/QTLs.