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 extract s sprays, viz, calotropis leaf suspension at 1% concentration or neem on at 0.5% concentration effectively controlled the leaf spot disease and signif icantly increased the yield over the control. A combination of mancozeb and carbendazim spray at 0.25 and 0.1% concentration, respectively, proved sig nificantly superior over the other treatments in controlling the disease an d increasing the yield. Spraying of fungicides proved to be highly effectiv e, and sprays of calotropis leaf suspension and neem oil were cost effectiv e. Significant differences in yield were not observed with the use of plant extracts at all the concentrations tested, however, lower concentrations g ave highest cost:benefit ratio. Potassium chloride spray at 1% concentratio n 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.