【作者】 闫绍鹏；

【导师】 王秋玉；

【作者基本信息】 东北林业大学 ， 林木遗传育种， 2004， 硕士

【摘要】 本文以引进的欧美山杨杂种（P．tremula×P．tremuloides）、欧洲山杨（P．tremula）和中国山杨（P．davidiana）10个无性系幼苗为试验材料，采用人工气候室对材料进行低温处理，研究山杨幼苗低温胁迫下ABA含量、可溶性蛋白含量和SOD活性的遗传变异，同时探讨外源脱落酸（ABA）和CaCl₂预处理对经5℃低温处理的山杨幼苗叶片电解质渗透率的影响。研究结果表明： （1） 欧美山杨杂种无性系低温胁迫下几种生理指标随处理温度和材料纬度的变化在各无性系幼苗间存在较大的遗传变异。ABA含量、可溶性蛋白质含量和SOD活性均与纬度呈显著正相关，与处理温度呈极显著的负相关。多项生理指标综合来看，来自于高纬度的欧美山杨杂种无性系在耐寒性上总体高于中纬度和低纬度的山杨杂种无性系，且欧美山杨杂种无性系在各项生理指标上均高于中国山杨对照。因此，可以推断引进的欧美山杨杂种将适合在我国东北地区栽种。 （2） 低温胁迫对欧美山杨杂种不同无性系的几种生理指标影响显著。低温处理后，欧美山杨杂种不同无性系叶片中ABA含量、可溶性蛋白质含量和SOD活性均发生明显的变化。来自于不同纬度的欧美山杨杂种在低温诱导下，ABA含量有显著的上升；欧美山杨杂种及中国山杨在低温胁迫下，可溶性蛋白质含量随着处理温度上升而下降。在对欧美山杨杂种不同无性系低温诱导下可溶性蛋白的SDS-PAGE分析中，发现了可能与耐寒性有关的30KD、41KD和57KD蛋白，在9号无性系中发现了低温锻炼过程中新产生的34KD特异蛋白；在低温胁迫过程中欧美山杨杂种无性系SOD酶活性变化表现为先增加后减少，然后再增加的趋势。 （3） 通过外源ABA、CaCl₂预处理后，杂种无性系EP0202低温锻炼后的叶片电解质渗透率与对照相比有一定程度的降低，耐寒性有一定的提高。其中外源ABA预处理的最佳条件是10^-5Mol·L^-1，预处理时间48h；CaCl₂预处理的最佳条件是5mM CaCl₂，预处理时间5d。更多还原

【Abstract】 In this paper, the seedlings from 10 clones of P. tremula XP tremuloides, P. tremula and P. davidiana are treated under the condition of low temperature in growth chamber with a certain humidity which can prevents the dehydration of the seedlings. The concentration of abscisic acid, soluble protein content and SOD activity of these clones in low temperature stress are tested, and the variation of above index among the clones is studied. By feeding abscisic acid (ABA) and CaCl2, the osmotic ability of the Aspen leaves in low temperature 5C is also discussed. The results are given as follows:(1) Great genetic variation exists among the clones in above physiological index under low temperature stress. The content of soluble protein and activity of SOD in different clones have positive correlation with latitude where the clones come, and negative correlation with temperature stress significantly. Generally to say, the hybrid of P. tremula XP. tremuloides from higher latitude has more tolerance than the other clones from lower latitude, and all of them are higher than Chinese aspen on these physiological index. So we can induce that the hybrid aspen of P. tremula X P. tremuloides will have good adaptability in north part of China.(2) Low temperature stress has notable influence to the hybrid aspen in some physiological index. The content of the abscisic acid and soluble protein, the activity of SOD all have clear changes. ABA concentration of the clones under the stress increases along with the latitude. The content of soluble protein decreases with the increase of the temperature stress. The result from SDS-PAGE of soluble protein indicates that some proteins may probably have related to plant cold tolerance, such as 30KD, 41KD and 57KD differential protein, and a new 34KD protein is found in clone E10479. Following to increase of temperature stress, SOD activity shows a trend with up-down-up.(3) By pretreatment of abscisic acid and CaCl2 to clone EP0202, the osmotic ability of the seedling leaves after low temperature stress decreases compared to the control. That means the cold tolerance of the clone EP0202 is improved in a certain degree. Both of 10-5Mol ABA treated for 48h and 5mM CaCl2 treated for 5d is the optimum pretreatments for cold tolerances of the plants.更多还原