Content Of Phenolic Acids In Different Poplars' Branch And Effect On Saperda Populnea L.

Saperda populnea L.is one of the most important stem borers in north China,and its damage trend is increasely severe year by year;the pest affects severely the growth of poplars and utilization of poplar wood,because wormholing is in the trunk of populus,so effectively prevention the pest is urgently required;phenolics are an important group in plant secondary metabolites,and are holded that they are important defense function of insect-resistant,bacteriostasis and food-resistant.The paper explores that whether phenolics play some role on resistance of damage of Saperda populnea L.or not,and provides a new possibility.The research extracted Benzoic acid,Chlorogenic acid,Vanillic acid,Caffeic acid,Cinnamic acid,Ferulic acid,Gallic acid,Coumaric acid,Sylicylic acid and Syringic acid in two-year old branch of xylem and phloem of Populus'Baicheng-2',Populusxxiaohei T. S.Hwang et Liang,P.russkii Jabl.,P.berolinensis Dipp.,Populus pseudo-simonii Kitag.,Populus.pseudo-simonii×P.nigra,Populus ussuriensis Kom.,P.stalintz Jabl,Poplusalba×P.berolinensis and Populus simonii Carr.,using the methold of organic solvent extraction,and have done by HPLC in order to mensurating the content of ten kinds phenolic acids in ten strains of poplars of xylem and phloem,and then the datum were treated with analysis of variance and correlation analysis,to compare difference and relationship at content of ten phenolic acids of different trains poplars' xylem and phloem;based on the result before, feed Saperda populnea L.with feed adding phenolic acids,and observe change of the growth of larvae weight,to find which kind of phenolic acid have inhibitory effects of the growth of larvae weight.At last,some phenolic acids are seeked for and determined preliminarily significant effects on enzyme activity by measuring POD,SOD,GSH-ST and TChE.On utilization of plant secondary metabolites has been done in order to establish the theoretical foundation and provide reference for prevention Saperda populnea L.The research results indicate that there is no gallic acid in any strains of poplars' xylem and phloem,and content of the other nine phenolic acids are diversity.the content of phenolic acids in poplars' xylem are lower than which in poplars' phloem;There is extremely significant level of the content of each phenolic acid in different strains poplar' xylem and phloem;the content of phenolic acids had positive correlation with others,positive correlation reach extremely significant level in vanillic acid and sylicylic acid,cinnamic acid and caffeic acid,benzoic acid and caffeic acid in poplars' xylem,the same on vanillic acid and sylicylic acid,vanillic acid and coumaric acid in poplars' phloem;positive correlation reach significant level in sylicylic acid and coumaric acid,sylicylic acid and caffeic acid,coumaric acid and caffeic acid in poplars' phloem,positive correlation of the other phenolic acids is not significant;the nine phenolic acids inhibit the growth of larvae weight in different extent,the effect of caffeic acid,sylicylic acid and cinnamic acid are obvious,protective enzyme activity of Saperda populnea L.can be inhibited by sylicylic acid,cinnamic acid,vanillic acid and syringic acid;detoxification enzyme activity of Saperda populnea L.can be inhibited by caffeic acid,sylicylic acid and cinnamic acid.A comparative analysis shows that caffeic acid sylicylic acid and cinnamic acid have effect on larvae in some extend.