EVALUATION OF FIVE INSECTICIDES AGAINST THE BLACK LEAFHOPPER (Ricania speculum Walker) ATTACKING PATOLA [Luffa cylindrica (L.) Roem]

Abstract

In the small plot trial; diazinon, permethrin, malathion, methyl parathion and endosulfan at the manufacturers' recommended rates and sprayed 4 times starting at flowering significantly controlled the nymphs of the black leafhopper. Highest yield and net return were obtained in malathion-treated plants. Diazinon gave the lowest yield and net return but these were still higher than those of the unsprayed control.
The results of the preliminary screening tests were confirmed in the large plot trial. Except for carbofuran, all other insecticides provided immediate control of the black leafhopper nymphs. Under non-shaded condition, yield was highest on endosulfan-treated plants while the methyl parathion-treated plants gave the highest net income/ha under shaded condition. These insecticides also seemed to have no deleterious effect on predatory spiders.