关键词: 马尾松毛虫, 耐药性, 蛋白质, 核酸酶, 羧酸酯酶, 多酚氧化酶

Abstract: The content of protein and activities of carboxylesterase (CarE) and polyphenol oxidase in larval stage of the massonpine caterpillar Dendrolimus pinctatus Walker showed positive correlation with age increase in instars. After treatment with fenvalerate, the content of protein and activity of Care increased during exciting stage but reduced to normal level during inhibitory stage. The activity of polyphenol oxidase showed less change. The activity of Dnase increased with age from third to fifth instar, but decreased in the sixth instar. The activity of Rnase showed negative correlation with the increase of larval instars. After applying fenvalerate, theactivity of Dnase began to drop and that of Rnase rose during exciting stage, but dropped to normal level during inhibitory stage. The results showed correlations among protein, nuclease and Care with insecticide tolerance, except polyphenol oxidase. Based on the results of toxicity test, it is clear that the insecticide tolerance of massonpine caterpillat increased with larval instars. The lethal dosage of fenvalerate to larvae in fifth instar is 2.8 times That to larvae in third instar and that to larvae in sixth instar is 2.3 times that to larvae in fourth instar. It will be rational to carry out chemical control before larvae in fourth instar.

Key words: Dendrolimus punctatus——pesticide, tolerancc——protein——nuc- lease——carboxylesterase——polyphenol oxidase