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The basic information on gene action and inheritance of quantitative traits, which is necessary to develop future breeding programme, is not widely studied in pigeonpea because it is a long duration crop and widely affected by stresses (biotic & abiotic). Therefore, present study was conducted among six generations in five pigeonpea crosses to know significance of additive-dominance model, gene action involved in inheritance of quantitative traits. These six population (P1, P2, F1, F2, BC1 and BC2) of five cross combinations of pigeonpea were studied during Kharif, 2014-15 for plant height, number of primary and secondary branches, pods plant-1, pod length, seeds pod-1, 100-seed weight and Seed yield plant-1.Significant deviation of scale(s) (A, B, C & D) from zero in all the crosses for most of the traits were evidence of presence of epistasis and hence further subjected to six parameter model to estimate the main gene effects (additive [ ] and dominance [hˆ] ) and their digenic interactions (additive × additive [iˆ] , additive × dominance [ ˆj] and dominance × dominance [lˆ] ). The estimates of six parameter model revealed that both additive and dominant gene effects were important in all the crosses for almost all the traits. However, the relative contribution of dominant gene effects was much higher than additive gene effects for plant height, pods plant-1, seed pod-1 and seed yield plant-1. Higher frequency of duplicate type of epistasis also confirms the prevalence of dominance gene effects for above traits except for seed yieldplant-1.

Eight intraspecific (four each of mungbean x mungbean and urdbean x urdbean) and 24 interspecific (eight each of mungbean x urdbean, mungbean x ricebean and urdbean x ricebean) crosses were made at five different dates of ten days intervals i.e., September 11-20, 21-30, October 1-10, 11-20 and 21-30 during kharif/late kharif seasons, 2015 to obtain a total of 32 crosses. The per cent crossability at five different dates indicated that it was the highest during October 1-10 in both intra - (mungbean x mungbean, 72.27%, urdbean x urdbean, 55.55%) and interspecific (mungbean x urdbean, 43.24%, mungbean x ricebean, 16% and urdbean x ricebean, 9.92%) crosses. Similarly, the percent ovule fertility recorded was also the highest during October 1-10 in both intra - (mungbean x mungbean, 90.00%, urdbean x urdbean, 83.33%) and interspecific (mungbean x urdbean, 75.00%, mungbean x ricebean, 71.42% and urdbean x ricebean, 60.00%) crosses. Optimum temperature (~22˚C) , followed by low humidity (49.0) and comparatively enhanced sunshine (>8.5 hours) might be responsible for accelerating the highest pod sett during October 1-10 and thus may be suggested as appropriate period for obtaining highest pod setting in Vigna species studied.