Tests Of Synergistic Actions Of Sarisan On Several Pesticides

Sarisan(1-Allyl-2-Methoxy-4,5-Methlene-Dioxybenzene)which is a kind of phenylpropanoid substance was isolated from Ligusticum sinense Oliv.,and its insecticidal activity was first reported by Research and Development Center of Biorational Pesticide,Northwest A&F University.To further vertify the bioactivities and mechanism of sarisan,the toxicity and action of sarisan against several normal pests were investigated under the laboratory conditions. Poisoning symptom was observed. Efects on some important physiological and biochemical criteria in Mythimna separates Walker were tested.The main results are given as follows:(1)Under the concentration ,the results showed that the effect among the mixtures on synergism,additive effect and antagonist was 2,3 and 1 respectively in the co-toxicity of 7 insecticide mixtures.The tendency of the co-toxicity was that sarisan mixtured with cyfluthrin or nicotine was synergism, sarisan mixtured with avermectin,methomyl,phoxim amitra or imidacloprid was additive effect and sarisan mixtured with cypermethrin was antagonist.(2)High synergism was observed with the fllowing mixture:sarisan plus nicotine (6:4 and 7:3),sarisan plus cyfluthrin(6:4,7:3,8:2 and 9:1).Their cotoxicity coeffients were 257.5,112.58,124.15,167.88,227.54,930.64.The synergism of sarisan mixed with nicotine was evaluated by the quadratic regression rotation composite design method. The co-toxicity coefficients (CTC) of mixture of them was257.5. The optimal mixture ratio was 6:4 between sarisan and nicotine.(3) In vivo symptom was characterized by a definite sequence of events,starting with excitation, convulsion, paralysis, and death. But some in paralysis could recover at a lower dose, Mythimna separates Walker, Pieris rapae L.and Musca domestica Linnaeus.hyperemesised when treated with sarisan, hollow duodenum phenomenon was found in Mythimna separata Walker.(4)Synergism of sarisan to nicotine was measured against Mythimna separates Walker.The result showed that the Mythimna separata Walker could inhibit activity of acetylcholinesterases(AChE),the effectiveness of inhibiting AChE is:mixture>nicotine> sarisan.The synergistic mechanism was also evaluated by analyzing the inhibitory AChE.Sarisan had a good development outlook for it had good bioactivity, wide spectrum, various actions and special mechanism; its characteristics also involve the simple structure. Furthermore, it is abundant in nature.