BIO-EFFICACY OF POTASSIUM SILICATE AGAINST APHIDS AND WHITEFLY IN POTATO

Abstract

ABSTRACT: Silicon is known to enhance the crop resistance to biotic and abiotic stresses through physical and allelochemical mechanisms. Therefore, the knockdown and residual toxicity of foliar applied potassium silicate (technical grade) to whitefly and aphids infesting potato crops was evaluated in separate trials over two years. Although no significant knockdown effect was associated with potassium silicate, the whitefly population reduced by 53.27% and 61.42% after 3 and 7 days of treatment, respectively, and aphid population by 57.81% and 48.98%, respectively with foliar application of potassium silicate @ 0.3%. The virus incidence (mild and severe mosaic, leaf roll and apical leaf curl) in potassium silicate treated plots was at par with those of recommended insecticides but much lower than control. Potassium silicate sprays increased the leaf silicon concentration significantly. Being compatible with organic cultivation, potassium silicate could be integrated in to the pest management module of organic potato cultivation where weekly application of potassium silicate @ 0.3% could keep the whitefly and aphid population and subsequent virus incidence under control.