Botanical pesticide from betel (Piper betle L.)

The potential of betel as botanical pesticide against pests of cotton was evaluated from 1997 to 2000. Findings showed that the crude volatile oil, its fractions and formulated product had considerable toxic effect on aphids, Aphis gossypii and leafhopper, Amrasca biguttula. Contact toxicity studies showed that the volatile oil fraction isolated by petroleum ether was found to be most toxic to A. gossypii with LC50 of .21%. For A. biguttula, petroleum ether-derived fraction and dichloromethane-derived fraction were most toxic at LC50 of .13%. The volatile oil and the formulated product at 5% rate effectively inhibited oviposition of Pectonophora gossypiella. It also showed promise as ovicide against cotton ballworm, Helicoverpa armigera and pink bollworm. Egg deposition of P. gossypiela adults was inhibited on substrate treated with volatile oil and formulated betel product at 5%. No significant trend was established from H. armigera. The crude volatile oil was found to be effective than any of its fractions as fungicide against damping-off organisms, Sclerotium rolfsii and Rhizoctonia solani and wilt pathogen, Fusarium oxysporum. The formulated betel product at 2% was more effective than Mancozeb with fungicidal efficacy of 57% for S. rolfsii; 49% for R.solani and 32.8% for F. oxysporum. The petroleum ether and dichloromethane fractions has six and three major components, respectively. The components were generally monoterpenes and sesquiterpenes, notably allylpyrocatechol, eugenol, phenols, cineol, cadinene and menthone. Field evaluation of the formulated betel product (60 EC) indicated a reduction in bollworm population at a lower rate than the check insecticides, deltamethrin and profenofos. It was more effective than deltamethrin against aphids but least against leafhoppers. Although seedcotton yield and other yield components indicated better performance at the check insecticides over the product, the apparent contact toxicity of the latter and less injury to the natural enemies are worth considering