Area-Wide Control Program of Chinese Citrus Fly Bactrocera minax (Enderlein) in Sindhuli, Nepal

Abstract

Citrus plays a significant role in providing nutrition to people and generating income for the citrus farmers in Nepal. Among various biotic problems in citriculture, Chinese Citrus Fly (CCF), Bactrocera minax (Enderlein) (Diptera: Tephritidae) has become a major threat to the production of the tight skin citrus fruits, viz. sweet orange, lemon and lime in recent years. This invasive species originated in China and seems to have entered into north-eastern Nepal through Bhutan and Sikkim (India). The damage to sweet orange (Citrus sinensis (L.) Osbeck) by CCF has shown a yearly increasing pattern since 2014 in the central hilly citrus orchards in the districts of Sindhuli and Ramechhap. Sindhuli district holds the first position in terms of sweet orange acreage and its production in Nepal. Conventional pest control measures including pesticide cover spray seemed to have resulted in limited effect in controlling CCF. Thus, as a pilot program, an Area-Wide Control Program (AWCP) of this pest was conducted in 40 ha of sweet orange orchards at Golanjor Rural Municipality-4, Tinkanya in Sindhuli, Nepal to minimize the fruit damages by maggots of B. minax. AWCP focused on the life cycle based management strategy of this pest, targeting the female adult fly population. Formulated protein bait (Great Fruit Fly Bait) containing 25% protein hydrolysate and 0.1% Abamectin was used as spot application underside of the 0.5 to 1 m² leaf for 10 times at a weekly interval from May to July 2018 as per the protocol developed by Ecoman Biotech, China. The result revealed that the leaf underside spot treatment with the protein bait was highly efficient to minimize the sweet orange fruit losses from 56.7 to 10.9%. Coordination among stakeholders along with sound technical aspect and managerial function seemed essential for the successful implementation of B. minax AWCP.