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The present investigation was conducted to understand the genetics of resistance to northern leaf blight in maize through six generation mean analysis in three crosses viz., PH234 X PH84K, PHM6M X PH17H and PHM6M X PHY0Z during kharif 2016-17. The scaling tests and joint scaling tests indicated the inadequacy of additive-dominance model and showed the presence of epistatic gene effects in all the three crosses for northern leaf blight. Further study revealed the importance of additive, dominance and additive × additive gene effects in the expression of the disease. The magnitude of dominance effect was more compared to additive gene effects. Duplicate gene interaction was evident in the inheritance of northern leaf blight resistance in all the crosses. The study also revealed that genetic architecture of northern leaf blight resistance was population specific. Both, additive and non-additive components were found important suggesting reciprocal recurrent selection as more effective for developing northern leaf blight resistant maize genotypes.

Rice is a water-loving crop and traditionally sown in the nursery and then transplanted to the puddled and waterlogged main field. Owing to climate change, water scarcity and labour shortage problems, rice is now cultivated in the dry direct seeded method. Owing to potential of hybrid rice in increasing both rice production and productivity, many countries are focusing on exploiting the benefits of this technology. To break the yield plateau in rice cultivation, Thermosensitive Genetic Male Sterile (TGMS) hybrids were found to be very effective. In the present study, 41 TGMS hybrids and 9 checks were evaluated for their stability and adaptability by dry direct seeded method in four locations viz., E1 - Allahabad, E2 - Lucknow, E3 - Dhamtari and E4 - Raipur. The TGMS hybrid G44 was predicted as an ideal hybrid by the GGE stability model that possessed high grain yield and stable performance over environments. It was followed by hybrids viz., G10, G14, G34, G11, G20 and G47 that had a stable performance with high yield. Hence, these TGMS hybrids were identified as high and stable yielders across environments and suitable for dry direct seeded rice ecosystems. Among the environments, E1 (Allahabad) and E4 (Raipur) were considered favourable environments as they possessed the highest discriminating power. The hybrids identified in the study can be utilized for breaking the yield barriers in rice and can be recommended for dry direct seeding in marginal and rainfed areas.