PEG干旱胁迫对内蒙古自治区辣椒苗期生理指标影响

Effects of PEG Drought Stress on Physiological Indexes of Pepper Seedlings in Inner Mongolia

为了解内蒙古地方辣椒品种间抗旱性差异并选育抗旱辣椒品种,本研究以3个辣椒品种为试验材料,在生长期采用PEG-6000水培模式模拟辣椒苗期干旱胁迫,测定干旱胁迫后辣椒苗期地上部分和地下部分长势、叶片中叶绿素相对含量、渗透调节物含量以及抗氧化酶活性等,研究不同辣椒品种对干旱胁迫的生理响应及抗旱性。结果表明,PEG-6000不同浓度干旱胁迫对不同辣椒品种的各项生理生化指标影响存在差异,辣椒地下部分对干旱胁迫的敏感度高于地上部分,随着干旱胁迫的加剧叶绿素相对含量与对照相比均呈现不同程度下降趋势,脯氨酸和丙二醛含量则呈现上升趋势,不同抗氧化酶活性均随着干旱胁迫加剧而逐渐上升,但是这些指标在不同辣椒品种间也存在显著差异。由于通过单一指标分析抗旱性存在片面性,因此我们采用隶属函数值法综合分析3个辣椒品种的抗旱性,结果显示‘鹿椒十九号’抗旱性最强,其次是‘鹿椒一号’,最后是‘慧丰九号’。本研究通过干旱模拟试验筛选出‘鹿椒十九号’是抗旱性较强的辣椒品种,为后期内蒙古自治区抗旱辣椒的选育和种植提供参考。

In order to understand and select drought resistant pepper varieties among the difference pepper varieties in Inner Mongolia,three pepper varieties were used as experimental materials,and simulated the drought stress in seedling stage by PEG-6000 water culture model in growing period.For understanding the physiological response and drought resistance of different pepper varieties,the growth potential,the relative content of chlorophyll,the content of osmotic regulators and the activity of antioxidant enzymes were measured in the seedling stage of pepper leaves.The results showed that there were differences in the effects of PEG-6000 on physiological and biochemical indexes of different pepper varieties.The sensitivity of the underground part of pepper to drought stress was stronger than that of the above ground part.With the increase of drought stress,the relative chlorophyll content decreased to different degrees compared with the control ratio,while the content of proline and malondialdehyde increased,and the antioxidant activity was different.The enzyme activity increased with the increase of drought stress,but these indexes also showed significant differences among different pepper varieties.Because of the one-sided drought resistance through single index analysis,we used the membership function method to analyze the drought resistance of three pepper varieties.The results showed that the LJ19 drought resistance of the three pepper varieties was the strongest,followed by the LJ1 and HF9.The study screened the LJ19 as a kind of pepper with strong drought resistance through drought simulation experiment,which provides reference for the breeding and planting of drought resistant pepper in Inner Mongolia.