Fruit spot disease of Phyllanthus emblica L. is one of theproblems, which reduce the quality of the fruits at pre-harvest period. Fungal pathogen was isolated using tissue planting methods during November 2016 to December 2017. The fungus, Thielaviopsis paradoxa was identified using both morphological and molecular characterization based on internal transcribe spacer (ITS) region of ribosomal DNA (rDNA). Mycelial growth of the isolated fungus was evaluated on six different fungal culture media viz, potato sucrose agar (PSA), Richard agar (RA), carrot agar (CA), potato dextrose agar (PDA), honey peptone agar (HPA) and Hansen’s agar (HA) in which RA and HPA media provided the utmost growth. The optimum temperature of the fungus was recorded at 25 to 35ºC. Alternate cycle of 12h/12h light dark and neutral to basic pH was preferred by the studied fungus. Aqueous crude extracts of three plants (garlic, black cumin, and turmeric) were evaluated against the isolated fungus in which the highest inhibition was recorded due to garlic extract. Two food preservatives (sodium benzoate and vinegar) were also tested in which sodium benzoate (100 mM) was most efficient for the inhibition of T. paradoxa. Therefore, garlic and food preservative-sodium benzoate could be used to control this fungal growth associated with amla fruits. To the best of our knowledge, occurrence of T. paradoxa on amla fruits is a new record in Bangladesh. Int. J. Agril. Res. Innov. Tech. 10(2): 38-46, December 2020

Fruit rot disease of strawberry caused by fungus is most economically important disease in Bangladesh, which reduces the production and quality of strawberry at both pre and post-harvest period. Present study was conducted to identify the causal organism of the fruit rot disease of strawberry through classical and molecular techniques and its eco-friendly control measures. A fungal pathogen causing fruit rot was isolated and identified as Botrytis cinerea through classical fungal taxonomy and molecular characterization based on their internal transcribed spacer (ITS) region of ribosomal DNA (rDNA). Sequence analysis showed that 5.8S of rDNA sequences were identical. The reciprocal homologies of the ITS region sequences ranged from 98 to 100%. Experimental results suggested that studied fungus (MH371474.1) was genetically similar with MF521935.1 Botrytis cinerea. Isolated fungus was evaluated on six different culture media and at five different temperature conditions. The optimum mycelial growth of B. cinerea was found on Richard agar medium at 25°C temperature at 7days post inoculation (dpi), while mycelial growth was drastically reduced the temperature 30°C and above. Three Trichoderma species viz., T. ressei, T. harzianum and T. asperellum were used to assess the antagonistic effect on isolated pathogenic fungus in which the mycelial growth of it was inhibited mostly by T. ressei. Experimental results revealed that Trichoderma ressei was the effective antagonistic fungus against Botrytis cinerea for the biological control.

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Fruit rot disease of Amla (Phyllanthus emblica L.) reduces the quality of the fruits and causes economic loss. An investigation was conducted to find out pre-harvest fruit rot fungal pathogen associated with Amla fruits. The fungal pathogen was isolated using tissue planting method. Both morphological and molecular characterization confirmed the pathogen identity as Pestalotiopsis sp. Result indicated that Pestalotiopsis sp. showed the highest radial mycelial growth on potato dextrose agar (PDA) medium. The utmost vegetative growth of the identified fungus was recorded at 25℃ on PDA medium, however, a range of temperature may be suitable for the fungal growth. Sodium benzoate and vinegar were tested against the fungus for food preservative. Sodium benzoate at 100mM concentration exhibited efficiency to inhibit the radial growth of the fungus. Chemical food preservatives-sodium benzoate could be used to control the growth of Pestalotiopsis sp., associated with Amla fruit rot disease. To the best of our search, quite a few attempts have been taken to investigate the fruit rot disease of Amla. Therefore, fruit rot disease caused by Pestalotiopsis sp., is the first record in Bangladesh. Jahangirnagar University J. Biol. Sci. 10(1 & 2): 71-81, 2021 (June & December)

Post-harvest spoilage of Amla fruits is one of the major problems which reduces the economic quality of the fruits. The goal of the present study was to identify the post-harvest fungal pathogens associated with Amla fruits based on morphological and molecular characteristics, growth characteristics of the fungi, and their eco-friendly control measures. The fungi were identified as Penicillium rolfsii Thom., Penicillium herquei Bainier & Sartory, Aspergillus aculeatus Iizuka, Aspergillus terreus Thom., and Mucor sp. Frasen. Penicillium rolfsii and Aspergillus aculeatus were preferred to grow on Richard Agar medium; Penicillium herquei grew the maximum on Potato Sucrose Agar medium; Aspergillus terreus was found to grow irrespective of culture media and Mucor sp. grew on all the tested media except Richard Agar medium. The optimum temperatures were recorded at 25 to 35°C for all of the fungi except Mucor sp., which preferred to grow at 15°C. Aspergillus aculeatus was able to grow on a broad range of pH (5 to 9); Penicillium rolfsii, Penicillium herquei, and Aspergillus terreus were grown better at neutral to slightly alkaline pH, while Mucor sp. on slightly acidic conditions. Aqueous crude extracts of garlic and black cumin were found to show inhibitory activity against all the fungi. Food preservative sodium benzoate was found to be the most efficient against fungal pathogens. Based on our findings, it is suggested that garlic extract and sodium benzoate could be used to manage the fungal growth associated with post-harvest Amla fruit diseases.