Study On Physiological And Bio-chemical Characteristics And Resistance Chemical Mechanism To Anoplophora Glabripennis Motsch Of Ailanthus Altissima

The paper studied not only the characteristics of water physiology and photosynthesis of Ailanthus altissima through measuring the variation of several water physiology and photosynthesis indexes of the seedling and the young trees, but the resistance chemical mechanism to Anoplophora glabripennis Motsch and it's application in mixed forest according the chemical components analysis of the extract of A. altissima and biologic test.The main results were as follows :(1) Under osmotic stress, there were significant variations for physiological indexes of the seedling. The RWC, free water content, chlorophyll content were reduced, but MDA content, proline content and POD activity were increased. The seedling could tolerate middle-extent osmotic stress (5%~10% PEG). During July to October, the variations of several basic water physiological indexes (MDA content, POD activity, etc.) of seedling and young trees of A. altissima were distinct, but the variation of SOD activity was not significant. (2) The net photosynthetic rate (Pn) of the seedling was between 11 umol m-2s-1 and 20umol m-2s-1, and it's maximum Pn was at the last ten-day of August. The Pn of the young trees was between 6umol m-2s-1 and l5 mol m-2s-1, and it had two peaks during July to October. The diurnal changes of Pn of seedling and young trees showed two kinds of curves. The light saturate point (LSP) and light compensate point (LCP) of seedling were 1841.67nmol m-2s-1 and 155.18 mol m-2s-1 respectively, but the LSP and LCP of the young trees were 1810.00 m-2s-1 and307.07 mol m-2s-1. (3) Comparing with other three tree species, the tree of heaven had special leaf POD isozyme patterns related with the characteristic of insect-resistance. The effects of the extracts distilled from half-wood-branches and leaves on seedling growth and cutting rooting of Populus bolleana Lauche were significant, but there was no effect on cabbage's seed germination. (4)The tree of heaven had significant inhibiting effect on growth, feeding and spawning of A. glabripennis, and the extracts and the chemical compounds that were main components of the extracts had scattering and poisoning effect to A. glabripennis. Above all, the four scattering and resisting active chemical compounds were acquired that were α-Pinene, β-Pinene, β-Caryophyllene and α-Terpinene.(5)The damage situation caused by A. glabripennis and it's host choice action were related with the mixed stand types of A. altissima and Populus bolleana Lauche. The results showed that best insect-resistance structures and types of the mixed stand of P. bolleana Lauche and A. altissima should be as follows: mixed in row or belt, and the mixed proportions was 3:2 or 1:1 or 2:3.