Abstract

                                Nine promising and divergent varieties of tomato (Lycopersicon esculentum Mill) were crossed as per exclusive reciprocals diallel design. Low magnitude of heterosis over better parent for PH was observed in 15 crosses which ranged from -1.13 (Sel. -18 X Pusa Ruby) to 13.88 per cent (NT-3 X Punjab Chhuhara). Two best hybrids for ascorbic acid content were Sel.-18 X NT-3 (19.50%) and Money Maker X Punjab Chhuhara (19.04%), where as the cross Pusa Ruby X NT-3 (46.97%) exhibited high degree of heterosis for shelf life of fruits. In case of seed weight per fruits maximuin negative heterosis was observed in cross Money Maker X Marglobe (-23.11%). However, three best heterotic crosses which were found promising as they coupled with other quality traits may be arranged in order Sel.-18 X Hisar Arun; Money Maker X Marglobe and Marglobe X Punjab Chhuhara, could be exploited commercially in hybrid varietal development programme. Inbreeding depression was also observed, though it was varied with crosses.

Key words : Heterosis, Inbreeding Depression, PH, Shelf life, Ascorbic acid