POST HARVEST DISEASES OF SOME SELECTED FRUITS, THEIR CAUSES AND MANAGEMENT

Abstract

A study was conducted at Plant Pathology Laborartory, Sher-e-Bangla Agricultural University, Dhaka-1207 during February 2019 to March 2020 to isolate, identify, and characterize the causal agents responsible for post-harvest diseases of fruits. Apple, pear, orange and papaya were used as samples and collected from different fruit markets in Dhaka city. Post-harvest fungi were isolated on PDA medium following blotter paper method. Four different genera of fungi were isolated and identified viz. Aspergillus spp., Penicillium spp., Fusarium spp. and Sclerotium sp. Of these, Aspergillus spp. was common in apple, pear, orange and papaya. Pathogenicity test showed all isolated fungi pathogenic to their respective host. Effect of different media, temperature and packaging on growth and development of isolated fungi was studied. Study was carried out by completely randomized design with three replications. All isolates showed variation in myceial growth, surface colour, colony colour, colony shape and colony texture. On PDA media, the highest radial mycelial growth (88.19 mm) was recorded in Sclerotium rolfsii (Apple) and lowest (23.62 mm) in Penicillium digitatum (pear) at 10 th DAI. At 30℃ temperature, the highest radial mycelial growth (90.00mm) was recorded in Sclerotium rolfsii (Apple) and lowest (23.53 mm) Penicillium digitatum (orange) at 10

DAI. In paper packaging, long days were required for deterioration in case of apple (60 days) and shortest days were required for deterioration in case of papaya (6days). Sclerotium rolfsii (Apple) showed best performance in radial mycelia growth observation (media and temperature) and apple showed best performance in all packaging observation. In this study, PDA medium, 30°C temperature showed best results for mycelial growth of isolated pathogen and paper bag showed best results for packaging of fruits at room temperature.