Abstract: In order to enrich the study of drought-tolerant germplasm resources of wild onion plants, and explore the differences in drought tolerance among common onion plant species in Inner Mongolia, and clarify the physiological response mechanism of onion plants in dealing with drought environment, the present study was conducted with wild adult Allium mongolicum Regel, Allium polyrhizum Turcz . ex Regel, and Allium tenuissimum L.. PEG 6000 solution was used to simulate four degrees of drought stress （15%, 30%, 45% and 60%）, and a control group （0%） was set up. The indicators of physiological and photosynthetic characteristics were measured on the 7th, 14th, 21st and 28th days, respectively. The results showed that with the increase of drought stress and stress time, the physiological indexes of the three plants differed from each other, and the free proline （Pro） and chlorophyll （Chl） contents were the highest in Allium tenuissimum L., the malondialdehyde （MDA） content was the highest in Allium polyrhizum Turcz, and the peroxidase （POD） activity and superoxide dismutase （SOD） activity both exhibited high activity in the leaves of Allium polyrhizum Turcz. ex Regel and Allium mongolicum Regel. The comprehensive evaluation of the drought tolerance of three Allium L. was conducted using principal component analysis （PCA） and membership function analysis. The results indicated that Allium tenuissimum L. exhibited the strongest drought tolerance. Under low drought stress of 15% and 30%, Allium mongolicum Regel demonstrated greater drought resistance than Allium polyrhizum Turcz. ex Regel. However, Allium polyrhizum Turcz. ex Regel displayed stronger drought resistance than Allium mongolicum Regel under higher drought stress of 45% and 60%. The results of this study could provide theoretical basis for the breeding and cultivation of drought tolerance in Allium L..

Key words: AlliumL., drought stress, physiological index, integrated evaluation of drought tolerance

摘要： 为丰富野生葱属（Allium L.）植物耐旱种质资源研究,探究内蒙古常见葱属植物种间耐旱能力差异,明确葱属植物应对干旱环境的生理响应机制,本研究以蒙古韭（Allium mongolicum Regel）、碱韭（Allium polyrhizum Turcz.ex Regel）、细叶韭（Allium tenuissimum L.）3种葱属植物野生成年植株为研究对象,采用PEG-6000溶液模拟干旱胁迫,设置对照组（0%）和4个不同程度干旱胁迫实验组（15%,30%,45%和60%）,分别于第7,14,21,28天测定生理和光合特性等指标。结果表明,随干旱胁迫程度增加和胁迫时间延长,3种植物生理指标变化存在差异。在受到胁迫后游离脯氨酸（Proline,Pro）和叶绿素（Chlorophyl,Chl）含量在细叶韭叶内含量最高、丙二醛（Malondialdehyde,MDA）含量在碱韭内含量最高,过氧化物酶（Peroxidase,POD）、超氧化物歧化酶（Superoxide dismutase,SOD）在碱韭和蒙古韭叶内均具有较高活性。通过主成分分析及隶属函数分析方法综合评价3种葱属植物的耐旱能力,耐旱能力最强的是细叶韭,蒙古韭在15%和30%较低浓度干旱胁迫下抗旱能力强于碱韭,而碱韭在45%和60%较高浓度干旱胁迫下抗旱能力强于蒙古韭。本研究结果可为葱属植物耐旱性育种和栽培提供理论依据。

关键词: 葱属, 干旱胁迫, 生理指标, 耐旱性评价