Characterization of Dry Matter Partition with Grain Yield in Advanced Breeding Lines of Rice (Oryza sativa L.)

The experimental field 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, SP-80, 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). Seven genotypes showed significantly higher leaf weight over the BPT-5204. Further, leaf weight at panicle initiation stage showed a positive relationship with TDM (Total Dry Matter) (r=0.51**). At the panicle initiation stage, only three genotypes (SP-354, SP-358, and SP-72) were superior to BPT-5204 in leaf weight. The shoot biomass and total dry weight was superior only in one genotype SP-72 as compared to BPT-5204. Similarly, the net assimilation rate at panicle initiation stage was maximum in SP-08 (9.92g m-2 day-1) and SP-72 (9.35g m-2 day-1) as compared to check BPT-5204 (6.47g m-2 day-1). These genotypes maintained higher photosynthetic rate (SP-72) and higher grain yield (SP-08). The relationship between CGR (Crop Growth Rate) and TDM (Total Dry Matter) and grain yield (r=0.61**) was positive and significant at physiological maturity. Genotypes SP-08 and SP-72 showed significantly higher CGR (Crop Growth Rate) over BPT-5204 and hence, yielded higher. In the present study compared to BPT-5204, genotypes SP-72, SP-08 maintained higher lea area index at all crop growth stages. These genotypes maintained higher photosynthetic rate (SP-72) and higher grain yield (SP-08). Positive significant relationship between LAI (Leaf Area Index) and total dry matter at harvest and; grain yield has been observed.