In order to provide scientific basis for early screening of wheat drought-resistant identification indices,and cultivation and utilization of wheat cultivars.A field trial was conducted to study the physiological and biochemical changes in leaves of six wheat cultivars (such as ' Qingmai No.6 ' ,' Jihan 5034 ' and ' Lumai 21 ' ) with different fertilizer and water types under PEG-6000 stress.The seedling survival percentage,root: shoot ratio and chlorophyll content all decreased,while the proline content and relative membrane permeability increased,the root activity revealed an appreciably increasing tendency and then declined with water stress time.The seedling survival percentage,root:shoot ratio,chlorophyll content and superoxide dismutase (SOD) activity of dry land type cv.' Qingmai 6 ' ,' Jihan 5034 ' and ' Lumai 21 ' were relatively higher and declined more slowly,while the relative membrane permeability was lower.The change amplitudes of these mentioned drought-resistance indices of cv.' Yannong 24 ' and ' Jimai 22 ' with high fertilizer and water types were larger;while those of cv.' Yannong 21 ' with moderate fertilizer and water types lied between high fertilizer and water types and dry land cultivars.' Qingmai 6 ' could maintain the relatively superior leaf structure and functional status under water stress,and the relatively high drought-resistance index,which led to its strong drought resistance.%为给小麦抗旱鉴定指标的早期筛选、小麦品种的培育与利用提供科学依据,在聚乙二醇(PEG-6000)水分胁迫条件下研究了6个不同肥水类型小麦品种幼苗期叶片生理生化的变化。结果表明,小麦品种随着水分胁迫时间的延长,幼苗干旱存活率、根冠比和叶绿素含量均降低,脯氨酸含量和细胞质膜相对透性均升高,根系活力先呈现略微升高再下降的趋势。旱地品种‘青麦6号’、‘济旱5034’和‘鲁麦21’的幼苗干旱存活率、根冠比、叶绿素含量和SOD活性较高且下降较为缓慢,而细胞质膜相对透性较低;高肥水品种‘烟农24’和‘济麦22’受水分胁迫影响较大,上述抗旱指标变化幅度较大;中肥水品种‘烟农21’的上述抗旱指标变化幅度介于高肥水和旱地品种之间。‘青麦6号’具有较高的抗旱指数,在水分胁迫条件下能够保持较好的叶片结构和功能状况,因而抗旱性较强。
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