Diversity of hemipteran insect fauna and their relative abundance in pigeonpea, Cajanus cajan (L.) Millsp

Abstract

The study on the hemipteran insect fauna associated with pigeonpea and their relative abundance was carried out at Chiplima, Odisha, India during 2019-20. A total of 18 hemipteran insect taxa belonging to 11 insect families were documented from the pigeonpea ecosystem during the study. Among them, nine taxa viz., Megacopta cribraria Fabricius, Otinotus oneratus (Walker), Clavigralla gibbosa (Spinola), Clavigralla scutellaris (Westwood), Aphis craccivora Koch, Piezodorus hybneri (Gmelin), Nezara viridula (Lin.), Empoasca kerri Pruthi, Riptortus linearis (Fab.) were most abundant in pigeonpea ecosystem. They were observed in vegetative to reproductive stages of the crop and mostly abundant in November and December. Among miridae family, two insects namely Poppiocapsidea (=Creontiades) biseratense (Distant) and Eurystylus bellevoyei (Reuter) were first time observed in pigeonpea in Odisha and under lygaeidae family, Graptostethus servus (Fabricius) was first time appeared as pest of pigeonpea. All the hemipteran insects’ incidence was negatively correlated with temperature and rainfall whereas positively correlated with morning relative humidity. Regression analysis showed that minimum temperature significantly contributed more than 40% variation to the high population built up of the insects belonging to plataspidae, coreidae, membracidae, cicadellidae and pentatomidae families.