CHEMICAL CONTROL OF STEM END ROT OF MANGO CAUSED BY LASIODIPLODIA THEOBROMAE

Abstract

Stem end rot is the most severe and widely prevailed postharvest disease of mango throughout the Pakistan. Lasiodiplodia theobromae was predominantly isolated from the mango fruits having typical symptoms of the stem end rot disease. Pathogenicity assay depict that faster and severe symptoms appear on mango fruit when they inoculated with disks of L. theobromae as compared to injection method. Range of chemical fungicides is use in pre- and post-harvest disease management. In present comparative studies of six fungicides [Carbendazim (Carbendazim), Gemstar (Azoxystrobin), Native (Tebuconazole+Trifloxystobin), Score (Difenoconazole), Tecto (Thiabendazole) and Tilt (Propiconazole)], lower used concentrations of Carbendazim followed by Tecto appeared as highly effective to inhibit the growth of L. theobromae on agar medium while at higher used concentration (30000 ppm) no growth of L. theobromae was observed with any fungicide. Generally, higher concentration of fungicides were more effective than the lower concentrations All fungicides more or less checked the pathogen infection on mango fruits inoculated with L. theobromae, as significantly minimum disease development was observed on treated fruits as compared to the untreated once (control). Nativo, Gemstar and Carbedazim at the lowest used dose (10000 ppm) reduced the lesion area while no lesion develops at 20000 and 30000 ppm in hot dip treatment at 50 ºC for 5 min.