Explore The Resistance Mechanism Of Different Cucumber Varieties To Thrips Palmi Karny

Thrips Palmi Karny is a worldwide pest to harm Cucumber. Currently the main control method of the Thrips Palmi Karny is chemical control.Misuse of it is not only pollute the environment but also easy to cause Thrips Palmi Karny resistance. So the application of resistant varieties is the most economical and eco-friendly measure of prevention and control Thrips Palmi Karny. In order to explore the resistance mechanism of different cucumber varieties to Thrips Palmi Karny, this experiment selects 5 cucumber varieties, they are No.1 white cucumber, No.2 local king cucumber, No.3 Xiafeng 6, No.4 Zhanghuang cucumber, No.5 Yadianfengyuan 168.They show differences in physical structure, nutrients, volatile substances and flavonoid on three different parts leaves of tender leaves, grown leaves and older leaves in 5 cucumber varieties.The main results are as follows:1.In five cucumber varieties,the feeding trends of T. Palmi was No.2 local king cucumber>No.4 Zhanghuang cucumber>No.3 XiaFeng 6>No.5 Yadianfengyuan 168>No.1 white cucumber. The average distribution ratio of T. Palmi populations on three parts leaves of tender leaves, grown leaves and older leaves in 5 cucumber varieties was 49.14%.37.11%、 13.75% respectively. It is indicated that T. Palmi prefer feeding on the tender leaves and grown leaves.2.The length of leaf hair of different cucumber varieties was significantly negative correlated with the number of T. Palmi.But the Number of leaf hair per cm2 of different cucumber varieties was significantly positive correlated with the number of Thrips Palmi.In one variety, the length and density of hair were significantly positive correlated with the number of T. Palmi among different parts cucumber leaves.3.Thickness of leaves, upper epidermis,lower epidermis, palisade tissue, spongy tissue and PT/ST were not obvious correlated with the number of T. Palmi among cucumber varietieson and different growth parts of cucumber leaves.4.Among different cucumber varieties and different growth parts of cucumber leaves, the soluble reducing sugar, total sugar, soluble protein are above moderate positive associated with the number of T. Palmi.5.Among different cucumber varieties, Alanine, threonine, glutamic acid, aspartate was positive correlated with the number of T. Palmi.Alanine was highly correlated with the number of T. Palmi, and the other amino acids were moderately correlated with the number of T. Palmi. Histidine, phenylalanine, tyrosine, cysteine and the number of Thrips Palmi were moderately negative correlation.17 kinds of free amino acids were not obvious correlation with the number of T. Palmi among different growth parts of cucumber leaves.6.Flavonoids content and the number of T. Palmi were not obvious correlation among cucumber varieties. Flavonoids content and the number of T. Palmi were significantly positive correlated among different growth parts of cucumber leaves in one variety.7.The alkenes and alkynes volatile volatilized from different growth parts of cucumber leaves may have attractive effect to T. Palmi Karny.The aldehyde and ketone volatile volatilized from different growth parts of cucumber leaves may have deterrent effect to T. Palmi Karny.