Influence of weather factors on the development of leaf spot of betel vine caused by colletotrichum capsici

摘要

Betel vine (Piper betle L.) is an important cash crop in India, Bangladesh, Malaysia, Sri Lanka, Pakistan, Mauritius and Myanmar. Plants of betel vine are cultivated in conservatories under shady and humid condition that favours the development of many diseases (Chattopadhayay and Maiti, 1990). Leaf spot caused by Colletotrichum capsici is one of the major disease of the crop (Bhale et al. 1987) that in severe condition lead to death of the plants producing up to 25-90 percent losses of the crop in different parts of India (Dastur, 1935; Chattopadhayay and Maiti, 1990). This disease of betel vine was first identified by (Roy, 1948) and it is also known as anthracnose of 'Pan' (vernacularly called as 'Jhalma'). The epidemic form of the disease in thecountry has also been reported by (Basak et al. 1992) and (Hossain et al. 1986), causing 10-60 percent yield loss (Singh and Joshi 1971, Maiti and Sen 1982). It reduces market value of the crop (Maiti and Sen, 1971). Environmental factors play an important role on the development of disease as they help the pathogen for growth, dissemination and infection as well as influences on expression of susceptibility/ resistance of the host plant after infection (Walker, 1965). Among the environmental factors,temperature, humidity and rainfall are the most crucial for the development of leaf spot of betel vine (Maiti and Sen 1982). So, the present study was undertaken to find the effect of weather factors on the development of the disease severity and to formulate suitable prediction equation.