【作者】 孟函宁；

【导师】 刘明国；

【作者基本信息】 沈阳农业大学 ， 森林培育， 2007， 硕士

【摘要】 沙棘属于抗旱耐瘠薄的生态经济型树种，在漫长的生存和进化过程中，对自然条件形成了强大的适应性。本研究是以不同品种沙棘为试材，以阜新和沈阳为实验基地，对不同品种沙棘的光合生理、水分生理及生长发育特性进行了深入系统的研究，旨在为沙棘的选育及抚育管理提供理论依据。本实验研究的结果表明：1．沙棘的生长特性：不同品种沙棘均在6月15日到6月30日期间，形成第一个生长高峰，此后急剧下降，接近或达到观测期间内的最低点，之后又逐渐上升，在7月15日到8月30日期间形成第二个生长高峰，此一阶段时间较长，基本能完成全年总生长量的一半左右；后又趋于下降，直至苗木几乎停止生长，苗木冠幅的扩展也具有一致的趋势。2．通过对5个品种沙棘的叶片组织结构进行实验与观察，表明各品种间叶片厚度、表皮毛密度、气孔密度、栅栏组织厚度等指标差异较大，各品种间表皮厚度、角质层厚度、气孔长度无明显差异。从形态观察和解剖结构看，抗旱性由强到弱的品种依次为阿列伊、辽阜二号、楚伊、向阳以及辽阜一号。3．沙棘的光合生理特性：沙棘的净光合速率无论是在阜新地区还是在沈阳地区均具有明显的日变化和季节变化，并且日变化总体来说均呈“午休”型的双峰型曲线，最高峰出现在12：00 A．M．前后，次峰出现在3：00 P．M．前后。沙棘的净光合速率的最大值均出现在八月份，最小值出现在九月份，进入十一月，气温转冷，光合速率很低，光照弱时接近零或低于零。4．沙棘的水分生理特性：沙棘的叶片含水量在整个生长季变化不大，基本在63.6％～72.04％之间，在阜新地区，沙棘的光合速率、侧枝生长量能维持在较高水平，表现出耐旱植物典型的生理特点；沙棘叶水势日进程呈早晚高而中午至下午低这一明显规律；辽阜2号的保水力最强，前两个小时失水最少且达到恒重的时间也最长；沙棘的蒸腾速率日变化均呈现明显的单峰型曲线变化，并且峰值出现在2：00 P．M．前后。5．不同沙棘品种抗旱性综合评价：通过主成分分析，综合评价沙棘抗旱性，得出抗旱性最强的为辽阜一号，依次为辽阜二号、楚伊、阿列伊和向阳。更多还原

【Abstract】 Sea buckthorn is a drought tolerance species in china. During the long period of living and evolution, it has been formed a strong adaptability to the environment. The research studied on the water and photosynthetic physiological characters of different Sea buckthorn species, at the same time, probe into the water requirement regularity and the drought resistance of Sea buckthorn .These results will provided scientific basis for the foster of the growth of thorn and anti-drought afforestation. The results are as follows:1. The mainly growth characters: Different sea buckthorn cultivals will achieve the first growth peak from the middle ten days of a month to the last ten-days of a month of June. Then descend suddenly, approach or achieve the minimum pot in the period of observation time. After that, there have a gradually ascend tendency. The second peak will form from the middle ten days of a month of July to the last ten-days of a month of August,this stage will last a long time, and at the same time, the Sea buckthorn will complete a half growth capacity of the whole year. Then decline again until the Sea buckthorn stop grow. The exception of these, the capextend of trees also has the same tend like this.2. Tissue parameters in leaves of different sea buckthorn cultivars were observed. The results showed that differences of leaf thickness, stoma density, stockade tissue thickness, ratio of stockade tissue thickness to sponge tissue thickness, CTR, SR, and size of upper epidermis cells and etc. are significant while differences of epidermis thickness, cutin layer thickness and stoma length were not.3. The research on photosynthetic physiology of sea buckthorn showed that: whatever in fuxin or in shenyang have obvious diurnal variation and season variation. There displayed a obvious midday-depression and double peak curve on bright sunny days in summer under normal cultivations .The net photosynthetic rate increased rapidly for a few hours after sunrise , reached a peak at about 12 A.M. , with was followed by marked decrease until about 2 EM. ,then increased again and reached a second but lower peak at about 3 EM.In addition to it,the maxium will appear at Auguest and the minimum will appeat at september.4. The research on water physiology of sea buckthorn showed that: during the whole growth seasons, the leaf water content had little change. The range from 63.6% to 72.04%, They all displayed parabolic shape, which peak value was at 11:00. The decreasing range of water content and water potential was small, and leaf growth rate of side shoot and photosynthesis rate in a higher level under the medium water stress area like fuxin, which showed the typical physiological character belonging to drought-enduring plant, In addition, The changes of transpiration in a day showed a single-peak curve, furthermore, the peak appear at the 2 P.M.5. Take advantage of principal component analysis, evaluate the drought resistance of sea buckthorn, we can conclude that liaoful has the strongest drought resistance.更多还原