Abundance, foraging behavior and pollination efficiency of insects visiting the flowers of Aonla (Emblica officinalis)

Abstract

Many insect species visit the flowers of a plant and play an important role in their pollination. Of late, the interest of the pollination biologists has been to determine their relative contribution towards the reproductive success of the plant. Such information is lacking on the pollinators of Aonla (Emblica officinalis Gaertn.), a plant of very high nutritive and medicinal importance. Therefore, let’s attempt to make this study to generate such information on this plant. The study was conducted on three varieties of Aonla (viz. Chakaiya, NA-7 and NA-10) for two years. An entire range of flower visitors of this fruit plant was captured with hand net from its field during its flowering period and were identified. On the basis of foraging mode, the flower visitors were characterized as pollinators and non-pollinators. Their abundances, foraging rates, activity durations and number of pollen grains carried on the surface were recorded, and these parameters were used to determine their relative contribution towards the reproductive success of this plant. Among the 12 insect species visiting the flowers of Aonla at the study site, 5 belonged to Hymenoptera, 6 to Diptera and one to Lepidoptera. Apis dorsata was the most abundant visitor having maximal foraging rate and carried maximal number of loose pollen grains, followed by A. mellifera, A. florea and Sarcophaga sp; other visitors had lesser values of these parameters. On the basis of these parameters, melittophilous mode of pollination was found to predominate in Aonla. However, the plant was found to be benefitted from the multispecies pollinator guild, and the pollinator diversity seemed to matter for maximization of pollination in Aonla. Therefore, there is a dire need to conserve the pollinator diversity