Diversity of Insect Fauna of Onion in Low And Mid-Hill Regions of Himachal Pradesh

Abstract

Present survey was undertaken to determine the diversity of insect fauna associated with rabi onion at three crop growth stages in ten localities representing two agroecological zones of Himachal Pradesh during 2018. A total of 13 insect species including ten pestiferous and three beneficial insects from six orders and nine families were observed. The pestiferous insects were Altica sp., Chromatomyia horticola (Goureau), Euconocephalus sp., Gryllus sp., Helicoverpa armigera (Hubner), Melolontha furicicauda Ancey, Nezara viridula L., Spodoptera litura (F.), Thrips tabaci Lindeman and Trichoplusia orichalcea F. and beneficial insects namely, Coccinella septempunctata L., Coccinella transversalis F. and Hippodamia variegata Goeze. Among these, T. tabaci and C. septempunctata were prevalent in all the ten localities during bulb initiation and development stage. Maximum diversity was observed during bulb initiation stage followed by bulb development, and Zone II was more diverse than Zone I; T. tabaci was found to be the dominant species on onion with relative abundance of 96.9%.