Department of Entomology and Apiculture, Dr Y.S. Parmar University of Horticulture and Forestry, Nauni, Solan-173 230, H.P., India.
Evaluation of neem product (Econeem), Melia azedarach extract and pongammia oil was carried out under the laboratory conditions. Econeem was quite effective in repelling (walk off) the population of the spider mites. After 24 hours of the treatment, the walk off in respect of adults was 86.7% and 90% at 0.35% and 0.4% whereas in case of larvae and nymphs, the walk off was 83.3% and 86.7% respectively. Walk off response was more prominent in the adults as compared to larvae. Amongst the adults males showed more walk off as compared to the females. Pongammia oil was tested under the laboratory conditions for observing its bio-efficacy against larvae and adults of two spotted spider mite. LC50 value for larvae was found to be 0.825% with fiducial limits falling between 0.79 to 0.87 per cent and for adults the LC50 value was 0.83% with fiducial limits of 0.79 to 0.87 per cent. Melia azedarach extract was also quite effective in repelling the population of the spider mites and males were found to show more walk off as compared to the females. After 24 hours of the treatment, the walk off in respect of adults was 83.3% and 93.33% at 0.9 percent and 1.0 percent whereas in case of larvae and nymphs, it was 76.7% and 86.7% respectively. Pongammia oil gave highest reduction in egg laying per female at all the concentrations followed by econeem and Melia extract. Pongammia oil was most effective in reducing the hatchability of eggs and was followed by econeem and Melia extract.
