Studies On Hardiness And Mechanism Of Copper And Zinc Element To Kernel-apricot

To the 5-old years Kernel-apricot seedlings that are all growing normally , We have studied yearly variation law of Copper [Cu] and Zinc [Zn] element of its organs including leaves , branches , trucks, thick and thin roots ; yearly variation law of Poly-phenol oxidase[PPO] and Superoxide dismutase [SOD] activity of its above-mentioned 5 organs; and by the analysis on the effect of different treatments by Cu and Zn on PPO and SOD activity ; the effect of different treatments by Cu and Zn on Malondialdehyde [MDA] content ; the isoenzyme electrophoresis experiment of PPO and SOD under different treatments by Cu and Zn , We have probed into the hardiness of Cu and Zn to Kernel-apricot and its machanism . The results shows , [1] the existence of Cu element relates to the chilling resistance of Kernel-apricot, and have something to do with extention growth of newly emerging branches , regeneration ability of absorbing roots and photosynthesis of leaf blade ; the existence of Zn element has a bearing on not only chilling resistance but also drought resistance . [2] As a kind of protection protein , SOD is closely related to the chilling resistance of Kernel-apicot; and at the same time it is also one of basic condition of drought resistance of Kernel-apricot.[3] From initial growth stage on , PPO flows cycling evidently to strong growth point of parts above grounds , the development of parts above grounds , especially of the development of branches and thick & sturdy growth of trucks has notable relationship with PPO, this point is mainly reflected by insect pests resistance of tree body and the ability of organs to recover life after seedlings suffer injury . [4] The determination results of MDA content under different treatments indicates , in the course of treatment by Cu and Zn peroxidation of Kernel-apricot has been restrained (lipid peroxidation of plant cells produces MDA ) , and this result holds identical view with the ferment activity analysis result that SOD activity rises by Cu and Zn treatments . and it also shows . the action that Cu and Zn raise hardiness ofKernel-apricot is embodied through the change of SOD activity , Cu and Zn can decrease superoxide free radical content, restrain lipid peroxidation of cells by raise SOD activity , so can enhance hardiness of seedlings . [5] the isoenzyme electrophoresis experiment of PPO manifests , PPO by Cu2+ treatment compared with treatments else increases one piece of isoenzyme ribbon , this result holds identical view with the ferment activity analysis result that PPO activity rises by Cu2+ treatment, and it also shows , the essence that Cu element promote PPO activity to rise is , a,Cu2+ induces to produce a kind of new isoenzyme to enhance PPO activity , and its molecular weight is between the two original isoenzyme ; b, Cu2+, as a activator , directly stimulates one of zymogen of original isoenzyme ,produces zymogen activation to enhance original isoenzyme activity , so can raise hardiness of seedlings.