Studies on flower visitors and their foraging activity on Sunflower (Helianthus annuus L.)

This study was carried out to determine the role of pollinators in Sunflower and their foraging behaviour in Zonal Agricultural Research Station, GKVK, University of Agricultural Sciences, Bangalore. In present study, twelve species of pollen and nectar feeders were visited on Sunflower during the flowering period, of which nine species were recorded from Hymenoptera, one from Diptera and two from Lepidoptera. Among all, major pollinators were Apis dorsata (38.09%) followed by Apis cerana (29.52%) and Apis florea (21.58%). Maximum activity of A. dorsata (6.63 bees) was observed at 9.00AM; A. cerana (6 bees) at 10.00AM and A. florea (3.00 bees) at 11.00AM. Handling time required for one probing into the flower was different across the Apis species and it was more in A. dorsata (7.05 Sec) followed by A. cerana (4.90 Sec) and A. florea (3.13 Sec.). With respect to yield parameter number of filled seeds were 76.56 per cent less in bagged condition compare to open pollination and yield also decreased by 84.94 per cent in bagged condition than open pollination. This study concludes that pollination by different honeybee species is the most significant contribution in production of Sunflower.