2种抗光肩星天牛杨树树皮和木质部生化物质分析

以新疆杨和沙林杨为对象，检测其在未受害和受害状态下树皮和木质部的生化物质含量或活性，从生化角度探讨2树种的抗虫机制。结果表明，未受害新疆杨树皮糖含量最高，受害沙林杨木质部糖含量最低；蛋白含量在受害新疆杨木质部最高，在未受害沙林杨木质部最低。在未受害情况下，沙林杨树皮中槲皮苷和白杨甙含量均高于在新疆杨树皮中的含量，而亚麻木酚素和类黄酮含量均低于在新疆杨树皮中的含量；沙林杨木质部的总酚含量高于在新疆杨木质部的含量。受害后，除单宁和类黄酮外，其他次生代谢物在沙林杨树皮中的含量均显著低于新疆杨树皮中的含量；沙林杨木质部的毛蕊花糖苷含量显著高于新疆杨木质部，白杨甙和总酚苷则相反。防御酶类测定结果显示，未受害沙林杨树皮中的SOD酶活性低于新疆杨中的活性，而PPO酶相反。受害后，沙林杨树皮中的PAL和木质部的PPO酶活性分别显著低于在新疆杨树皮和木质部中的活性；沙林杨树皮中的SOD活性显著低于其在木质部的活性；POD酶在沙林杨受害树皮中的活性最高，在受害木质部中的活性也显著高于在未受害木质部中的活性。因此，沙林杨树皮和木质部中的POD和SOD酶与防御天牛危害有关,新疆杨受害木质部中的PAL和PPO酶升高与光肩星天牛的钻蛀有关。

An Analysis of Bio-chemicals of Two Poplar Species Resistant to Anoplophora glabripennis

Poplar is one of the main host tree species of Anoplophora glabripennis.Populus deltoides ’Shalinyang’ (PDB) and Populus alba var.pyramidalis (PAP) both show resistance to A.glabripennis to some extents,but their resistant performances are different.In order to explore the insect resistant mechanism from bio-chemical aspect,we quantified the second metabolites and enzyme activities in the uninfected and infected bark and wood of both PDB and PAP.The results showed that the quantity of soluble sugar was the lowest in the wood of infected PDB but was the highest in the uninfected PAP bark,and protein was the highest in the wood of infected PAP but the lowest in the wood of uninfected PDB.When uninfected,the quantities of quercitrin and aspen in the PDB bark were significantly higher than those in the PAP bark; the quantities of flax lignan and flavonoids in the PDB bark were significantly lower than those in the PAP bark; the quantity of total phenolics in the wood of PDB were significantly higher than that in the PAP wood.When infected,the quantities of most secondary metabolites in the PDB bark were significantly lower than those in the PAP bark,except for the tannin and flavonoids; the quantity of verbascoside in the PDB wood was significantly higher than that in the PAP wood,while the quantities of aspen and total phenolic glycosides were on the contrary.For the defense enzyme,the activity of superoxide dismutase (SOD) enzyme in the uninfected PDB bark was lower than that in the uninfected PAP bark,but the polyphenol oxidase (PPO) enzyme was contrary to it.When infected,the activity of phenylalanine ammonialyase (PAL) enzyme in the bark and PPO in the wood of PDB were both significantly lower than those in the PAP bark and wood,respectively; the SOD activity in the PDB bark was significantly lower than that in their wood; the activity of POD was highest in the infected bark of PDB among all samples,and it was also higher in the infected wood than that in the uninfected wood of PDB.Therefore,POD and SOD enzyme in the bark and wood of PDB were related to the infection of A.glabripennis.The increasing of PAL and PPO enzyme activities in the wood of PAP were also influenced by the infection of A.glabripennis.