Vol. 11, Special Issue 11 (2022)

Author(s):
Rakshitha TN, Prabhu ST, Tippannavar PS, Hegde RV and Naidu GK

Abstract:
Stingless bees play an important ecological role and identified as the ideal pollinators for crop pollination under protected cultivation. The present study was carried out to know the activity of stingless bee, Tetragonula iridipennis in pollination of gherkin crop cultivated under greenhouses located in seed farm, Ranebennur taluk, Haveri district, Karnataka of southern India during two seasons, rabi (2020-2021) and kharif (2022). At the time of flower initiation five stingless bee colonies were introduced inside the greenhouse. The activity of outgoing foragers started at 07:00 AM and continued up to 06:00 PM with peak activity at 11.00 AM to 12.00 PM (100.40 foragers 5 min^-1) during rabi. In kharif, activity of bees started from 08:00 AM till 06:00 PM with peak activity at 11:00 AM to 12:00 PM (92.80 foragers 5 min^-1). Among the incoming foragers, pollen foragers commenced from 09:00 AM with maximum activity at 10:00 AM to 11:00 AM (36.80 foragers 5 min^-1 in rabi and 27.20 foragers 5 min^-1 in kharif). Whereas, nectar foragers initiated from 07.00 AM and 08.00 AM during rabi and kharif season, respectively with peak at 11.00 AM to 12.00 PM (85.00 foragers 5 min^-1 in rabi and 75.20 foragers 5 min^-1 in kharif). Nectar foragers found throughout the day up to 06.00 PM. The flower sex type selection index of stingless bee was 0.479 indicates strong preference to male flower. Thus, stingless bee, T. iridipennis Smith are the prominent foragers of greenhouse cro0070.