Weather driven pollination efficiency and foraging activity of stingless bee, Tetragonula iridipennis Smith in chilli, Capsicum annum

The core objective of this study was to determine suitable pollination methods among stingless bee pollination, open pollination with stingless bee colony and self-pollination, along with the foraging activity of bees in relation to weather influences and their impact on fruit yield and qualities. This investigation was carried out during the Kharif and Rabi cropping seasons using 3 different pollination methods. Bee foraging activity in relation to weather factors was observed at different times of day during the flowering period until the first harvest of chilli fruits and yield attributes were ascertained from all treatments. Results showed that during the Kharif and Rabi cropping seasons, the foraging activity in open pollination supplemented with stingless bee peaked between 1200–1400 h and 1100–1200 h with outgoing bees (28.6 and 25.2 bees/5 min/h), pollen foragers (8.4 and 4.3) and nectar foragers (27.0 and 21.4) respectively. Furthermore, the peak resin foragers (3.7) were observed in Kharif between 1600 – 1700 h and in Rabi (2.3) between 1100–1200 h. In both seasons, all foragers were positively influenced by temperature and wind, whereas negatively influenced by rainfall and relative humidity. Amongst Kharif and Rabi cropping, the yield attributes like the number of flower setting/plant (183.67 ± 11.90 and 177.00 ± 14.76), number of fruit setting/plant (82.67 ± 1.25 and 80.00 ± 0.82) and yield (1099.33 ± 69.93 and 984.20 ± 108.59 kg/ac) were maximum in the open pollination with stingless bee, followed by bee and self-pollination. These findings underscore the significant role of stingless bees in increased chilli production. Detailed foraging behavior in relation to weather factors was studied to inform future crop-specific manageable pollination.