Morphology, Prevalence and Pathogenicity of Fungi Associated with Diseased Betel Vine (Piper betle L.) in Bangladesh

Three different fungal diseases were found prevalent namely leaf spot, leaf rot, and foot and root rot of betel vine at five different upazillas of five districts in Bangladesh. Phytophthora parasitica causing leaf rot, Colletotrichum piperis causing leaf spot, and Sclerotium rolfsii causing foot and root rot have been found. The highest incidence (41.60 per cent) and severity (21.86 per cent) of leaf rot disease were recorded at Mohanpur upazilla during the period of August. Minimum incidence (4.24 per cent) of leaf rot was recorded at Kaligong upazilla while minimum severity (2.83 per cent) was recorded at Gouronadi upazilla. The highest incidence of disease (57.44 per cent) and severity of disease (28.32 per cent) of betel vine leaf spot were recorded at same locations and same period of time as per leaf rot disease. Minimum incidence (8.32 per cent) and severity (2.72 per cent) of disease were recorded at Sitakundo upazilla during the period of May. In August at Gouranadi upazilla, highest incidence of disease (27.80 per cent) was filed in case of betel vine foot and root rot while the lowest incidence (6.00 per cent) of disease was reported at Sitakundo upazilla. Lesion sizes were varied in ranging 1.4-2.3 cm in diameter while isolates collected from Mohanpur showed highest pathogenicity caused by Phytophthora parasitica produced lesion 2.3 cm and lowest pathogenicity was recorded by Sclerotium rolfsii produced lesion 1.4 cm isolates collected from Mirpur and Mohanpur. In respects of locations and survey period, it was revealed that betel vine leaf rot and leaf spot were prevalent in Mohanpur upazilla during the month of August under Rajshahi district, and betel vine foot and root rot in Gouronadi upazilla under Barisal district.