Genetic variability studies in M2 generation of rice variety PDKV Tilak (Oryza sativa L.)

The present investigation aimed to assess genetic variability in the M₂ population of Rice and to identify superior mutants for advancement to subsequent generations. Genetically pure seeds of PDKV Tilak were irradiated with gamma rays at a dose of 300 Gy at BARC, Trombay (Mumbai). These seeds were sown to raise the M₁ population during the Kharif 2023 season at ZARS, Sindewahi. Dist. Chandrapur. Superior plants from the M₁ generation were selected and harvested individually for advancement to the M₂ generation. The experiment continued in the Kharif 2024 season at ZARS, Sindewahi. A total of 500 M₁ individual plant selections (IPS) were sown, from which 287 plants were identified as desirable mutants, along with 5 control plants, to study genetic variability parameters. The selected individual mutants were evaluated for fifteen different traits. Among all traits studied, high genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) were observed for the number of productive tillers per plant and mortality percentage. High PCV and moderate GCV were recorded for grain yield per plant, while moderate GCV and PCV were observed for the number of spikelets per panicle and number of filled grains per panicle. . High t-values from the t-test for all fifteen traits indicated highly significant variation between the selected mutants and the control population. superior mutants were identified based on traits such as high grain yield, increased panicle length, slender grain type and high number of spikelets from the 287 randomly selected individual M₂ plants. These identified mutants will be further evaluated and advanced to subsequent generations.