Insecticidal Effects of Cattle Urine and Indigenous Plant Extracts Against Sugarcane Mealybugs

摘要

Laboratory investigation was carried out to evaluate the repellency and toxicity effect of fermented cattle urine, neem seed kernel, mahagoni seed and allamanda leaves extract @ 5, 10 and 15 percent concentration against mealybugs of sugarcane. All the extracts had repellent and toxic effect against mealybugs of sugarcane. The repellency effect of fermented cattle urine @ 15% was more (67.80%) than others. On the other hand, the mortality percentage of mealybugs was highest (68.66%) due to toxic effect of mahagoni seed extract @ 15% at 72 hours after treatment (HAT) than others in the same concentration and time. The repellency and mortality rate increased proportionately with the concentration and time. The LC_(50) values indicated that allamanda leaves extract (0.66%) at 24 HAT, fermented cattle urine (0.25%) at 48 HAT and mahagoni seed extract (0.07%) at 72 HAT were the most toxic. Comparing the three probit regression equations lines, the highest probit mortality was found with fermented cattle urine at 24, 48 and mahagoni seed extracts at 72 HAT.