Studies on Screening and Inheritance of Yellow Stem Borer (Scirpophaga incertulas Walker) Resistance in F2 and F3 Segregating Generations of Rice (Oryza sativa L.)

This study investigated the screening and inheritance of resistance to yellow stem borer (Scirpophaga incertulas) in F2 and F3 segregating generations of rice (Oryza sativa L.) derived from six crosses viz., ADT 43 X TKM 6, ADT 43 X ASD 12, ADT 45 X TKM 6, ADT 45 X ASD 12, ASD 16 X TKM 6 and ASD 16 X ASD 12. Field screening was conducted during the 2021 and 2022 kharif seasons, evaluating white ear damage as an indicator of resistance. The F2 and F3 populations showed a range of resistance levels from highly resistant to highly susceptible across the six crosses of rice. The distribution of resistance varied, with the cross ASD 16 x TKM 6 having the highest number of highly resistant plants in F2, while ADT 45 x ASD 12 had the lowest in both generations. Chi-square analysis revealed that the inheritance of resistance followed a complementary gene action epistasis with a 9-resistant to 7 susceptible ratios observed in all six crosses across both generations. The screening helped identify promising yellow stem borer resistant segregants, which can be further investigated at the genomic level for molecular characterization and mapping of resistance QTLs to facilitate their introgression into rice breeding programs.