Studies On The Insecticidal Activities, Isolation Of Components And Preparation Of Acorus Gramineus Soland

It is a focus for the study of botanical pesticides to find bio-active natural products from plants. And it is very interesting to isolate these compounds and to make use of them as new agrochemical or leading structure for new agrochemicals.Methanol extracts, acetone extracts, petroleum extracts and water extracts from 15 plant species were tested for their insecticidal activities against Mythimna separate Walker, using direct contact application and stomach poisoning method. The result showed that Acorus gramineus Soland possessed the highest activities.Acorus gramineus rhizome was extracted by methanol, acetone, chloropreparation, petroleum, ethyl acetate and water respectively. And the anti-feeding, contacting, stomach poisoning and inhibiting growth activities of six extracts against Mythimna separate Walker were tested. The results showed that six extracts possessed bio-active difference. Methanol extracts showed the greatest activities mainly in anti-feeding, contacting and inhibiting growth activities. In an anti-feeding test, methanol extracts caused 91.89% anti-feeding ratio against Mythimna separate Walker at 2 days after treatment. In a stomach poisoning activity and inhibiting growth test, the weight of tested larvae was significantly lower than that of control in the treatment of methanol extracts, which gave 100% mortality in 4 days after treatment. Petroleum extracts and ethyl acetate extracts also showed clear inhibition on the growth of Mythimna separate Walker. Tested larvae in control had all become pupae at 13 days, but the larva period delayed for 5 days in the treatment of petroleum extracts. There were even no pupae at 18 days in the treatment of ethyl acetate extracts. Besides, methanol extracts showed high ovicidal activity against Mythimna separate Walker. Over 50% ova didn't incubate treated by it while waterextracts possessed no ovicidal activity.Methanol extracts were successively extracted by petroleum chloropreparation and ethyl acetate. And the petroleum extracts were isolated and purified by column chromatography and thin-layer chromatography (TLC). Through direction of bio-assay, one major compound with insecticidal activities was separated out. The Rf limit was 0.40~0.45, which got to first base for the identification of components.The insecticidal activities of essential oil of Acorus gramineus rhizome against stored pests, such as Sitophilus oryzae, Callosobnichus chinensis and Lasioderma serricorne, had been reported. But the anti-feeding activity, growth inhibiting activity, ovicidal activity and so on against Mythimna separate Walker were first reported here.In this paper, EC preparation from 25% extracts of Acorus gramineus rhizome was studied. At the same time, the bio-activities of different EC were also tested.