Quantitative Genetic Statistics to Predict the Sources of Favourable Dominant Alleles Not Present in the Parents of Elite Bitter Gourd ( <scp> <i>Momordica charantia</i> </scp> L.) Single Cross Hybrids

ABSTRACT Genetic improvement of popular elite single cross hybrids (SCHs) is considered as the most economical and fast‐track approach to enhance the productivity of hybrids in crops including bitter gourd. This approach requires improvement of parents (I 1 and I 2 ) of elite SCHs. This in turn requires (i) a priori identification of donor inbred lines (I d s) containing favourable dominant alleles not present in I 1 and I 2 of elite SCHs, (ii) identification of which parent (I 1 /I 2 ) of SCHs to be improved and (iii) prediction of the kind of breeding population (BP) (F 2 /backcross) to be used to develop improved version of identified parent of SCHs. Under these premises, we evaluated test cross (TC) hybrids (across two seasons) derived from crossing 16 advanced breeding lines (ABLs) as candidate donor inbred lines with parents (as testers) of the three elite SCHs namely Mayura, Aachi and OSBT‐03 for fruit yield. We estimated the predictor statistic ‘μG’, which quantifies the number of favourable dominant alleles present only in ABLs but not in the parents of elite SCHs. Based on this predictor statistic, we identified ABLs as the best I d s for improvement of parents of the three elite SCHs. Using the relationship estimator statistic (μC + μF/μD + μE), we identified that seed parents of the three elite SCHs are to be improved. Further, based on the magnitude of ‘μG’ relative to ‘μD/μE’, which guides the type of BP to be used to develop improved version of the identified seed parents, we predicted that improved versions of seed parents of the three elite SCHs need to be developed from populations derived from backcrossing the ‘F 1 ’ involving seed parents and I d s with superior parent.