Kashinath Chiluwal¹*, Roshani Ghimire2 , Salina Magar² , Sambriddhi Ghimire² and Lalit Shah^{2, 3
1}Directorate of Agricultural Research/NARC, Lumle, Kaski, Nepal
²Himalayan College of Agricultural Sciences and Technology, Kirtipur, Kathmandu, Nepal
³ iDE Nepal, Lalitpur, Nepal
*Corresponding author's email: knchilu@gmail.com
*ORCID iD: 0000-0002-3316-5640

Abstract

Owing to the superior quality and taste, Nepalese citriculture, especially the mandarin, is famous both at local and global market. However, recent invasion of Chinese fruit fly (CFF) Bactrocera minax (Enderlein) has posed a serious export threat of the mandarin. A semi-structured questioning with commercial citrus farmers of Gandaki Province to unveil the CFF-related issues and a field level assessment of the CFF pupal density to predict the future damage potential of the pests were carried out. The study showed that the mandarin growers were facing sever CFFinfestation since 3-4 years. They reported that the fruit drops started in July-August and peaked in September of the season leading into an average yield loss of 16.63±1.68% in Gandaki Province, the highest (20.94±4.34%) suffered by the farmers from Syangja. Though 64% of the respondents were adopting collection and disposing of the fallen infested mandarin fruits which led into a significant decrease (78.95±5.69% in 2021 and 72.48±3.17% in 2022) in CFF pupal population, there were plenty of larvae gone for pupation which could be sufficient to infest the nextseason mandarin. Moreover, ~ 22% of the respondents were not caring the fallen fruits which could be the major next-season source of the CFF adults. So, an area-wide control measure focusing on orchard sanitation, chemical sprays and baiting could be the immediate action for the control over CFF. However, investigation on the pest phenology in Nepalese context, search of wild hosts of the CFF and immediate technical backstopping to the citrus communities are imperative.