Insect Pests of Citrus Fruits and their Management Practices in Sahajpur, Kailali, Nepal

Abstract

The study was conducted in Sahajpur, Kailali, Far Western Nepal from September 2018 to February 2019. One hundred Citrus plants were selected randomly from both commercial (30%) and non-commercial (70%) cultivated sites of the study area. Insects were collected by Hand-picking, yellow pan trap, and beating method. By using questionnaire method and informal discussion with farmers the pest management status was assessed in the study area. The study recorded 10 citrus insect pests species belonging to three insect orders and nine families. Among them, Hemiptera (74%) was the most abundant order followed by Lepidoptera (21%) and Diptera (5%) was least abundant. Aphididae (44.65%) was the most abundant family followed by Gracillarirdae (10.23%) and Tephritidae (4.65%) was least abundant. The Shannon-Winner diversity index was calculated to be 2.132, with Pielou’s species evenness as 0.926. The study found that 60% insects were minor pests and 40% pest were major pests of citrus. Insect pests are responsible for variety of damages ranging from moderate to severe resulting in yield loss. The highest abundance was found on the month of November (92 ± 2.42) followed by in month of January (86± 0.86) and the lowest abundance was recorded in month of September (44 ± 0.23). The study reveals that infestation rate gradually increases from September to December and gradually decreases thereafter. Highest damage percentage was observed in December (18%) and lowest in September (5%). There was positive correlation between abundance of insect pest and damage percentage. Majority of the farmers (33%) used chemical pesticides, 28% adopted mix methods, 27% used Cultural methods and 12% used bio-pesticides for the control of insect pests. It was found that majority of farmers did not adopt safety precaution during pesticides application due to the lack of awareness and knowledge of pesticide handling.