The Study On Changing Regularity Of Physiological And Bio-chemical Indexes Under Drought Stress Of Seabuckthorn

In this paper nine varieties of seabuckthorn were used including Hippophae rhamnoides ssp. sinensis, Hippophae rhamnoides and hybrids of them were chosen to comprehensively evaluate the drought resistance. Systematic comparison study was done on their cell membrane permeability, osmotic adjustment matter, soluble protein, MDA, protective enzymes, SOD, POD, CAT isozymes, etc. And also their acclimation to drought stress was analyzed, in order to accumulate data to investigate drought resistance mechanisms of Seabuckthorn, and providing theoretical basis for the plantation and management of young trees of seabuckthorn. The main results of research are as followings:1. Under drought stress, damage of cell membrane,MDA content and increased. Compared with weak drought-resistance seabuckthorn there were less accumulation of MDA content and lighter damage of cell membrane in the leaves of strong drought-resistance seabuckthorn when stressed by drought.2. The changes in protein components and the relationship between these changes and the drought resistance of seabuckthorn under water stress were studied. The results indicated that soluble protein contents decreased–falled-decreased. Proline content persist increase. Compared with weak drought-resistance seabuckthorn there were higher osmotic adjustmen in the leaves of strong drought-resistance seabuckthorn when stressed by drought, showed that there was stronger adjustability of water stress in strong drought-resistance seabuckthorn than weak drought-resistance seabuckthorn.3. Along with the intensity increasing of drought stress, the activity of SOD and POD showed increasing at the beginning and decreasing at the end of stress, the activity of all varieties reached peak at middle-prophase basically, and after that, activity of POD decreased more sharply than SOD.4. There was distinct difference of different varieties of seabuckthorn in adjustability of water stress and water balanceable mechanism. Using Fuzzy synthetic evaluation gained the ability of drought-resistance: Zhongguo > Taiyang (♀) > Chuyi (♀) > Azhula (♀)> Ayaganka (♀) > Chuyi > Taiyang > Azhula > Ayaganka.5. Superoxide dismutase isozymes, peroxidase isozymes and catalase isozymes all changed under water stress. Bands color and numbers all changed, a part of isozymes disappeared activities and bands, others part isozymes activities distinct increase or appeared new bands. At the same time, there was significant difference in different genotype of seabuckthorn in Superoxide dismutase isozymes, but peroxidase isozymes, catalase isozymes has not big difference. Such results would facilitate seabuckthorn breeding for improving drought resistance and the new bands were relative to the mechanism of drought resistance.