Male sterility and its utilization for crop improvement in ridge gourd Luffa acutangula (L.)Roxb.

Abstract

The present investigation on male sterility and its utilization for crop improvement in ridge gourd is undertaken with the objective of investigating the stability of male sterility in ridge gourd Luffa acutangula (L.) Roxb. and expression of male sterility on combinations with different pollen parents of diverse groups. Micropropagation was effective in maintaining the male sterile line. Standardized protocol was followed for in vitro maintenance of male sterile line. In vitro regenerated plants exhibited stable male sterility all round the flowering season. Pollen fertility found to be zero in all the male sterile plants. Cytological analysis of pollen mother cells revealed normal meiosis in form of tetrad formation and pollen degradation found to be in post meiotic stage. Fourteen ridge gourd genotypes were collected from different parts of the country and evaluated for variability with respect fourteen traits. The genotypes exhibited significant variability for the characters studied. Genotypes were grouped into five clusters based on Mahalanobis’s D2 statistics. Five pollen parents from diverse groups were selected for hybridization with the male sterile female parent. Heterosis values were estimated over mid, better and standard parents. Out of five hybrids, four were male sterile and one was partially fertile. Inheritance of male sterility and restoration of fertility is a complex mechanism and the available information on male sterility is not sufficient to explain this unique mechanism. Available result points towards the presence of partial dominant gene action in controlling male sterility. The pattern of inheritance of male sterility and restoration of fertility can only be explained by studying the F2 and back cross generations and the three way cross involving male sterile hybrids and the pollen parent which restores the fertility.