In vitro efficacy of different fungicides against Fusarium incarnatum causing fruit rot of papaya (Carica papaya L.)

Abstract

Papaya (Carica papaya L.) is an important and most widely grown fruit crop of both tropics and subtropics of the world, belonging to the family Caricaceae and ranks third in importance among fruits. Papaya fruits lose their market value due to damage caused by many fungi. These fungi by their prolific growth, deteriorates fruit quality. Among these, fruit rot caused by Fusarium incarnatum adversely affects the fruit quality, quantity and ultimately reduces the market value. The fruit rot of papaya causes enormous yield losses, often in field and markets. Detailed investigations on various aspects were carried out in the present study during 2019-20. The papaya fruits showing typical characteristic symptoms of fruit rot were collected from Pachkandil vegetable market, Dhule. Infected fruits exhibited water-soaked spots at stem-end portion and also showed softening and mummification of fruits. In severe cases, rotten fruit showed white creamy growth of the pathogen. The pathogen was isolated by standard tissue isolation method and purified by single spore technique. Pathogenicity of fungus was proved by following Koch’s postulates. The fruit rot causal fungus was got identified by Agharkar Research Institute (An Autonomous body under the Department of Science and Technology, Govt. of India, G. G. Agarkar Road, Pune – 411 004) as Fusarium sp. aff. F. semitectum Berk & Ravenel (Current name- Fusarium incarnatum (Desm.) Sacc.) (ID.NO.3/426/2019/MYC/1135). In vitro efficacy of fungicides, revealed that carbendazim 12% + mancozeb 63% WP (0.2%) and hexaconazole 5% EC (0.1%) completely inhibited mycelial growth of the test fungus, followed by carbendazim 50% WP (0.1%), propineb 70% WP (0.25%), mancozeb 75% WP (0.25%). Whereas, it was least with thiophanate methyl 70% WP (0.1%).