Diversity, abundance and pollination efficiency of insect pollinators of fennel (Foeniculum vulgare Miller) and effect of abiotic factors on insect pollinator activity

Biodiversity of insect pollinators on fennel cv. HF-143 (Foeniculum vulgare Miller), was studied in Hisar, Haryana, India. Twenty-five insect species belonging to fifteen families of five orders were recorded from fennel flowers, in which, seven belong to order Lepidoptera, nine to Hymenoptera, five to Diptera, three to Coleoptera and one to Odonata. Among the insect pollinators, Apis florea F., A. cerana indica F., A. mellifera L. and A. dorsata F. were the most frequent visitors. Among different bee species, the maximum mean population observed in case of A. florea (9.23 bees/m2/5 min) followed by A. mellifera (3.62 bees/m2/5 min) and A. dorsata (3.21 bees/m2/5 min), whereas, the least abundance was observed in case of A. cerana indica, i.e., 1.82 bees/m2/5 min. The pollination index of A. dorsata was highest (19715210) followed by A. florea (13888381), A. mellifera (13845052) and A. cerana (5586381). Hence, it was observed that A. dorsata was the most efficient pollinator followed by A. florea, A. mellifera and A. cerana on fennel cv. HF-143 flowers under agro ecological conditions of Hisar (Haryana). Hence, insect pollinators were essential to get good returns in this seed crop. The activity of different bee species on fennel varied with different abiotic factors and had significantly positive correlation with bright sun shine hours (BSS) and temperature (TEMP) in different hours of the day during foraging but had negative correlation with relative humidity (RH). It was observed that the effect of wind velocity on foraging of different bee species was not significant. Thus, the impact of abiotic environmental factors may decide the foraging activity of different insect pollinators.