Flower Visiting Beetles in Vegetable and Home Garden Plants of Bheemdatta Municipality, Kanchanpur, Nepal

Abstract

Beetles are most abundant insect fauna and many of them are herbivores feeding variously on the floral parts as well. While feeding on flowers they pollinate different plants in tropics and interact to their host plants with different preferences. Study on composition and such interactions of beetle fauna to vegetable and home garden plants is scanty in Nepal so, this investigation was initiated to explore the flower visiting beetles at Bheemdatta municipality, Kanchanpur district, Nepal. Sampling was carried from October 2020 to July 2021 covering autumn, winter, spring and summer seasons. Sampling plots of area 20 m ×20 m area were chosen randomly and observed for 45 minutes, only sites that have optimum blooming were carried further for observations. Study results documented 1,219 individual beetles representing 20 species belonging to five families as flower visitors which were found interacting with 27 plant species from 15 plant families. Chrysomelidae was the most abundant beetle family recorded both by species number (8 species) and number of individuals contributing (68.50%, i.e. 835 individuals). Beetle fauna were most abundant in autumn (n=819) with highest diversity and richness (H'=1.60 and S=11) in summer while evenly distributed (J=0.70) in spring season. Overlapping of beetle species was highest between autumn and summer seasons (JA,Su =0.4), indicating they share more common species. Bipartite plant-pollinator interaction network was developed to find the interaction pattern among the flowering plants and visiting beetle species in the study area. Among the plants visited by beetles, Cucurbitaceae was the most visited plant family by 871 beetle individuals. Seven plant species of the family were present in study area and major were Cucurbita sp., Luffa acutangula, Luffa aegyptica, Lagenaria siceraria which were visited dominantly by Aulacophora foveicollis and Aulacophora lewisii. Coccinellid beetle Micraspis univittata visited the most number of plants i.e. 16 out of 27 plants observed.