杜仲杂种优良无性系抗旱性间接评价

以7个杜仲无性系22-22、2-23、4-30、17-17、2-32、6-30、5-152和2个对照品种（无性系）秦仲2号（Qinzhong No.2）、龙拐（Longguai）为对象，以其2年生嫁接苗成熟叶片为材料，采用常规石蜡切片法研究叶片解剖结构、扫描电镜技术观察气孔结构和压力室技术测定水分生理指标，用主成分分析法筛选主要指标，用隶属函数法对各无性系抗旱性进行对比分析。结果表明，共筛选出栅栏组织厚度、原初渗透势、气孔开度、厚角组织厚度4项主要指标，12项解剖结构参数、5项水分生理指数和5项气孔参数，均在无性系间差异显著，无性系抗旱性排序为:6-30>4-30>龙拐>秦仲2号>17-17>5-152>22-22>2-23>2-32。研究结果可对进一步筛选杜仲优良无性系提供参考依据。

Indirect Evaluation of Drought Resistance of Excellent Individual Clones of Eucommia ulmoides Hybrids

Two-year-old grafted seedlings of 7 clones of Eucommia ulmoides(22-22,2-23,4-30,17-17,2-32,6-30,and 5-152) and two referential cultivars( Longguai,Qinzhong No.2) were used as research objects to examine the drought resistance of the clones.The leaf tissue structure was studied by paraffin sectioning,the stomatal structure was observed by scanning electron microscopy,and the water physiology characteristics were measured by pressure chamber technique.Principal component analysis was used to screen out the main indicators.The drought resistance of each clone was compared and analyzed by membership function method.The results showed that 12 anatomical parameters,5 water physiological indexes and 5 stomatal parameters were significantly different among the clones,and clonal drought resistance ranked as:6-30>4-30>Longguai>Qinzhong No.2>17-17>5-152>22-22>2-23>2-32.The research results could provide references for further screening of excellent clones of E.ulmoides.