Plant pollinator interactions in mango with special reference to dipterans

Abstract

Mango crop pollinator assemblage and abundance was recorded in twenty locations newlineacross India. The pollinators documented were Apis cerana Fabricius, Apis florea Fabricius, newlineApis dorsata Fabricius, Apis mellifera Linnaeus, Tetragonula iridipennis (Smith), Vespa newlinetropica (Linnaeus), Camponotus compresses Fabricius, Chrysomya megacephala Fabricius, newlineLucilia sp., Sarcophaga sp., Stomorhina discolor Fabricius, Eristalinus arvorum Fabricius newlineand Musca domestica Linnaeus. Diversity and density of pollinators were different in the newlinestudy locations, which was evident from the diversity indices analysis. Highest pollinator newlinediversity ws observed in Bangalore (11) followed by Bangarupalem (7), Krishnagir (7) and newlineThalapulapalli (7). As flowering peaked during the observation period pollinator activity also newlineincreased. Among the eleven varieties of mango observed for pollinator activity, Alphonso newlineattracted more number of pollinators followed by Ratna and Amrapalli. With respect to nectar newlinevolume positive correlation was observed for C. megacephala, S. discolor and T. iridipennis. Similarly positive correlation was observed pollen grains per anther and the activity of A. newlineflorea and S. discolour. Among the 6 floral characters studied in bisexual flowers filament newlinelength showed positive correlation with pollinator activity, but among the four characters newlinestudied in male flowers, no correlation with pollinator activity could be observed. Chrysomya newlinemegacephala prefered to land on tip of inflorescence with no preference on flower age and newlineoften move short distance while foraging and handle up to three panicles in a foraging bout. newlineEristalinus arvorum spent less time per flower and forage on less number of flowers per newlinepanicle. Stomorhina discolor was found foraging on three panicles on an average, and prefer newlineto land on fresh flowers. E. arvorum and S. discolor showed flower scanning (hovering) newlinewhile approaching the panicle. All the dipterans studied exhibited grooming behaviour while newlineforaging. Abdomen bending was peculiar to E. arvorum. Chrysomya megacephala exhibited newlinemore fidelity to mango pollen. In general, female flies carried more mango pollen and spend newlinerelatively more time per flower than male flies. Among the attractants Cane juice (10%) was newlinemore attractive to A. florea and fish wash attracted more C. megacephala. Pollination by bees newlineand flies were on par with each other in terms of number of fruit set per panicle. Fruit newlinecharacters such as fruit length, width, fruit volume and TSS were superior in open pollinated newlineand insect pollinated fruits over the fruits obtained from pollinator exclusion experiment. newlineThis study explores the behaviour and feasibility of flies in mango pollination newline