Floral Biology and Breeding Behaviour in Karanj (Pongamia pinnata L. Pierre)

Studies on reproductive biology and breeding behaviour in karanj (Pongamia pinnata) indicated that the initiation of buds appeared along with new foliage during first half of April. Inflorescence was a raceme or panicle with 43-88 floral buds which took 13-16 days to bloom. Anthesis was acropetally. Above 70 percent buds opened between 0630 to 0830 hrs. Hermaphrodite flowers began to close at 1730 hrs onwards and closed completely by 1900 hrs of the same day. Peak flowering was from 13 to 21 days. Pod setting and development was maximum from June to August. Complete development and maturity took some 323-344 days. The dehiscence of anther started 2-3 h prior to anthesis and stigma receptivity was approximately one hour after dehiscence and continued till 1500 hrs. Honeybees, wasps and thrips were the major pollinators. Since there was no pod setting under selfing bags and open pollination was considerably low (9.6 to 40 per cent), the species appears predominantly cross fertilizing.