Showing papers on "Chrysanthemum indicum published in 1990"

Insecticidal Actions of Several Plants to Callosobruchus Chmensis L.

Abstract: Nine plants were evaluated for their insecticidal actions on Callosobruchus chinensis L: Agcratum conyzoides, Blumea baJsimifera, Chrysanthemum indicum, Coleus amboinicus, Vitex negun-do, Azadirachta indica, Cocos nucifera, Capsicum frutesccns and Piper nigrum. By filter paper impregnation method, the oils of the first seven plants exhibited contact toxicity with mortality ranging from 66 to 100% at 100 mg/ml, 48 hrs after exposure. At the same concentration, the oils were more toxic when mixed with the seeds, giving 100% mortality at 24 hours. C. amboinicus oil was the most toxic causing 93% mortality at 10 mg/ml within 15 minutes exposure, while the rest of the oils gave mortalities ranging from 43 to 100% 24 hours after exposure. Seed treatment at 5 mg inhibited egg laying by 71 to 100%. Mungbean seed treated with ground P. nigrum and C frutescens at 600 ppm was very toxic (91% mortality) after 48 hours exposure and was residually toxic 6 months after treatment to the weevils. P. nigrum inhibited the development of Fl progenies. Exposure of the bean weevil to mungbean treated with oils/extracts/powders from the test plants exhibited one or a combination of the following actions: toxicity, repellancy, antioviposition and growth inhibition. GC-mass infrared analysis of the volatile oil from sambong and its fractions showed the presence of sesquiterpe-noidal compounds. Purification and identification of the active compounds are in progress.