Insecticidal Spectrum Of Extracts From Corydalis Aduncam, Ways And Mechanism Of Extracts Against Mythimna Separate

The thesis researched insecticidal spectrum of extracts from Corydalis adunca Maxim, ways and mechanism of extracts against the larvae of Mythimna separate Walker. The main results show as following:1.C. adunca Maxim was extracted by 5 five species different polar solvents, getted different weight crude extracts. Production rate of methanol crude extract was the highest, and ethyl crude extract was the lowest. Ranked orders of production rates from polar solvents show as following: methanol > ethanol > petroleum >ether acetone> ethyl acetate.2.Contact effects on methanol extract (diluted 5 times ) against the 3rd instar larvae of M. separate Walker was the strongest, and the correct mortality was 15.5%. Contact effects on chloroform fraction from the methanol extract to the larvae was the strongest, corrected mortality was 87.5%, toxicity regression equations was Y=-5.0987+4.5675x, and LC50 value was 13.07 g/L.3.There were contact effects on different solvents extracts from C. adunca Maxim against Pieris rapae L, Myzus persicae Sulzer and Tetranychus cinnabarinus Boiduval. Respectively, contact effects on ethyl acetate extract (diluted 30 times) against M. persicae Sulzer,A. gossypii Glover,M. avenae Fabricius had ordinary action, and correct mortalities was 34.44%, and contact effects on methanol extract (diluted 100 times) against T. cinnabarinus Boiduval had actions, a certain extent ,and the correct mortality was 20.63%. Actions on methanol extract against the 4th instar larvae of P. rapae L was very strong, the correct mortality was 94.10%, and antifeeding rate was 100%.4.Methanol extract (diluted 5 times) to the larvae of M. separate Walker had contact effects,stomach poisoning effects and strong anaesthesia actions, but, extracts had not antifeeding effects, steaming effects,contact ovum effects and contact pupa effects. Actions chloroform fraction from the methanol extract against the 3rd instar larvae of M. separate Walker toke effect very strong contact and stomach poisoning effects, and corrected mortalities were 87.50% and 91.38%, respectively. Development inhibition effects on chloroform fraction from the methanol extract against the 3rd instar larvae of M. separate Walker was very strong, and the development inhibition rate was 88.66%. In addition, the petroleum extract had strong anaesthesia actions to the 5th instar larvae of M. separate Walker, the anaesthesia rate was 78% in one hour,and regression equation was Y=3.6206+2.5895x, values of RT₅₀= 3.41 h.5.The fraction of ethyl acetate from C.adunca Maxim had,a certain extent,inhibition effects on Na⁺-k⁺-ATPase,Carboxylesterase and Alph-Amylase in 5th larvae of M. separate Walker.