Reproductive phenology, flower biology and pollination in jamun (Syzygium cuminii L.)

Studies on reproductive biology in jamun (Syzygium cuminii L.) revealed that period of flowering ranged from 3rd week of February and continued till 2nd week of March under sub-tropical conditions. The tree canopy had 5–13 panicles per shoot, the number of buds panicle−1 ranged from 19 to 73 in different directions of canopy, panicle size had clear relation with number of flowering buds. The total flowering phase culminating in fruit set and later ripening lasted for 119 to 126 days with long phase of flower bud initiation, lasting for 45–50 days. Natural pollen transfer in the species was efficient and fruit set following open-pollination was quite high. Inspite of synchronous nature of anther dehiscence and stigmatic receptivity, selfing in a flower was found to coexist in nature with cross-pollination due to pollinator efficiency and pollen grain size. Selfing was promoted by geitonogamous mode and the species was suited to insect and wind pollination. It was found that reproductive phenology in jamun under Lucknow conditions was largely governed by seasonal climatic variables.