PEG模拟干旱胁迫对不同烤烟品种生理特性的影响

以抗旱性不同的烤烟品种中烟14和中烟100为材料，采用不同浓度的聚乙二醇（PEG-6000）模拟不同程度的干旱胁迫，研究不同干旱胁迫程度下不同品种烟叶内丙二醛和脯氨酸含量变化以及对烟叶内保护性酶活性的影响，探究烟草对干旱胁迫的响应机理，为烟草的抗旱筛选提供一定依据。研究结果表明，随着胁迫时间的延长，丙二醛呈现增加的趋势，且相同胁迫时间内，PEG浓度15%处理，叶片中丙二醛含量最高；脯氨酸含量随着胁迫时间的延长不断增加，在相同胁迫时间内，PEG浓度15%处理叶片中脯氨酸含量最高；随着胁迫时间的延长，超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）均呈现先升高后降低的趋势，且在处理1 d时达到最大值，PEG浓度15%处理酶活性最高。通过检测数据证实中烟14的抗旱性较强，各项检测指标用于烟草抗旱性研究具有可靠性。

Effects of Drought Stress Simulated by PEG on Physiological Characteristics in Different Flue-cured Tobacco Cultivars

in order to explore the mechanism of tobacco response to drought stress and to provide a basis for drought resistance screening in tobacco, an experiment was carried out to study the changes of MDA and proline contents and protective enzyme activities in leaves of flue-cured tobacco varieties Zhongyan 100 and Zhongyan under different PEG-6000 concentrations. The results showed that, MDA showed on a trend of increase with the time of stress treatment and at the same treating time, MDA content was the highest under the 15% concentration of PEG. Proline increased with the time of treatment and at the same treating time, proline content was the highest under the 15% concentration of PEG. The activities of superoxide dismutase (SOD), peroxdase (POD) and catalase (CAT) increased firstly and decreased subsequently with stress time, reaching the maximum activities after 1 day, with the highest activities under the 15% concentration of PEG. Zhongyan 14 was confirmed to have higher drought resistance, suggesting that the detection indexes in this study can be used in drought resistance evaluation of tobacco.