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Study On The Induced Resistance Of Larix Gmelinii To Insects

Posted on:2007-07-29Degree:DoctorType:Dissertation
Country:ChinaCandidate:W XuFull Text:PDF
GTID:1103360185955596Subject:Forest Protection
Abstract/Summary:PDF Full Text Request
Larix gmelinii is main specie of forest in northeast area of China. Dendrolimus superans (Butler) boomed since 90s and serious harmful result was seen. In this research, Larix gmelinii was selected as object for research. Temporal variation of chemical compounds in Larix gmelinii , effects on the choices of Dendrolimus superans feeding and oviposition and the change of gut digest enzymes and detoxified enzymes of Dendrolimus superans were performed to analysis through treatment of mechanic wounding in different degree, mimic insect feeding , JA, SA and some other signal compounds.The influence of different elicitors on induced resistance of Larix gmelinii to insects and relative physiological and biochemical mechanism of Dendrolimus superan were analyzed from the angles of nutrition, protective enzymes, defensive proteins, secondary metabolites and so on. Our research expected to offer theory support for improving the healthy level of forest and control of population density of Dendrolimus superan. After two years research, results were listed below:1. Changing of compounds of Larix gmelinii induced by mechanical wounding After wounding soluble proteins and the amounts of 17 anmino acids raised by inducing quickly and waved later, at 15d the amount higher than control in larch needles. The component percents of amino acids changed significantly during the course of 6h-3d, in which the contents of sugar dropped , which indicated that there is fast and defensive metabolic reaction caused by wounding. The activity SOD increased quickly and 2 peaks can be seen at 6h and 24h. CAT increased significantly after 6h, and 2 kinds of protective enzymes played their role together to eliminate the radicals from defensive metabolism in time. The activity of PAL increased during 5 days after wounding and the induced role of PPO followed behind PAL, but maintain for longer time. Wounding increase the amounts of 2 kinds of protein inhibitors (Tripsin inhibitor and Chymostatin), 6 kinds of phenolic acids and tannins which last long time with wave.Different degree of mechanic wounding has no significant relationship with the changing of compounds in larch. 25% and 50% wounding increased the amounts of sugar, the activities of protective enzymes and defendant enzymes significantly. And 75% wounding play a significant role on the amounts of soluble proteins, amino acids and tannins, but the results come out lately compared with slight wounding.2. Different elicitors effect on the compounds in needles of Larix gmelinii After treated with different elicitors, the contents of soluble proteins increased and the contents of sugar dropped. The expression level of PAL, PPO, tripsin inhibitor and...
Keywords/Search Tags:induced resistance, Larix gmelinii, Dendrolimus superans, insect behavior responses, digestive and detoxified enzymes
PDF Full Text Request
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