Study On The Insecticidal Active And Action Modes Of Nicandra Physaloides (L.) Gaertn

The Pesticides Laboratory of the Institute of Plant Protection,Gansu Academy of Agricultural Sciences,screened out Nicandra physaloides(L.)Gaertn. from 84 plant samples which can kill insects effectively.The results showed that the extracting rate of methyl alcohol extract from stems and leaves in florescence stage was 13.16%.the ethyl acetate and petroleum ether extracts from seeds were 12.56% and 12.50%, the petroleum ether extract from roots was just 0.68%.The death rate of contacting effect on methyl alcohol extract from stems and leaves in florescence stage to Mythimna separate Walker was 30.53%,and the death rates to Pieris rapae(L.),Plutella xylostella( L.),Mamestra brassicae(L.)and Laphygma exigua (Hubner)were 55.00%,21.43%,24.32% and 19.15%,respectively.The death rates of contacting effects on petroleum ether extracts from stems and leaves in full flowering stage to Aphis gossypii(Glover),Macrosiphum avenae (Fabricius)and Tetranychus cinnabarinus(Boiduval)were 74.02%,63.39% and 56.45%, respectively.The death rate of contacting effect of ethyl acetate extract from seeds to Myzus persicae(Linnaeus)was 61.96%.There was antifeeding effect for methyl alcohol extract from stems and leaves in florescence stage to M.separate(Walker).The antifeeding rate was 42.75%, the growing inhibition rate was 39.30%.There was narcotism effect to M. separate(Walker),RT were 5.38 hours,the confidence degree were 4.66—6.23 hours.There were no the effect of fumigation,inhibiting eggs and pupae.There was antifeeding effect for methyl alcohol extract from stems and leaves in florescence stage to P.rapae (L.),the antifeeding rate was 99.43%,there were no fumigation effect and systemic effect to M.persicae(Sulzer).Ethyl acetate fraction from methyl alcohol extract of stems and leaves in florescence stage had strong contacting effect to M.separate(Walker),the death rate was 61.00%, the linear regression equation was Y=-1.2323+4.7028X,related coefficie was 0.9820,LC50=2.1146×10-2mg/ml,95% confidence was 1.9616×10-2—2.2796×10-2mg/ml.