Phytochemical and biological studies of pyracantha fortuneana as a promising protectant to stored weat grains

ABSTRACT

Pyracantha fortuneana [Rosacea] was investigated chemically and biologicallyto evaluate its insecticidal activity as a protectant against two weevils;namely, Sitophilus oryzae L. and Sitophilus granarius L. Petroleum etherextract of the fruits was found to be the most effective, from whichbeta-amyrin, 24-dihydrolanosterol [24-methylene-5 alpha-lanost-8-en-3beta-ol, stigmasterol, beta-sitosterol, erythrodiol and ursolic acid wereisolated and identified. Biologically, the fruit extract was more effectivethan that of leaves. The percent mortality was directly proportional to theconcentrations used. The extracts showed a very weak repellent effect on theweevils. The bioresidual effect of the petroleum ether extract lasted for sixmonths, and decreased by storage periods. It provided satisfactory protectionto stored wheat grains against damage and weight loss. Seed viability washigher when using higher extract concentrations