Comparative effects of plant extracts and chemicals for the management of leaf spot of groundnut (Arachis hypogaea L.)

The effect of some plant extracts and chemicals on the management of tikka leaf spot of groundnut (Arachis hypogaea L.) was investigated by conducting an experiment under field conditions. Results indicated that plant extracts sprays, viz, calotropis leaf suspension at 1% concentration or neem on at 0.5% concentration effectively controlled the leaf spot disease and significantly increased the yield over the control. A combination of mancozeb and carbendazim spray at 0.25 and 0.1% concentration, respectively, proved significantly superior over the other treatments in controlling the disease and increasing the yield. Spraying of fungicides proved to be highly effective, and sprays of calotropis leaf suspension and neem oil were cost effective. Significant differences in yield were not observed with the use of plant extracts at all the concentrations tested, however, lower concentrations gave highest cost:benefit ratio. Potassium chloride spray at 1% concentration also significantly reduced the disease spread and significantly increased the yield over the control and it was at par with other treatments except fungicidal spray.