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[目的]探索巴西香蕉幼苗对PEG-6000模拟干旱的生理响应。[方法]以巴西香蕉(Musa AAA Cavendish subgroup cv.Brazil)幼苗为试验材料,利用PEG-6000人工模拟干旱胁迫环境,设3个胁迫强度处理(5%、10%、15%)和3个胁迫持续时间(24、48、72 h)研究干旱胁迫下巴西香蕉幼苗生理指标的变化。[结果]不同胁迫强度和胁迫持续时间处理的香蕉幼苗叶片相对含水量,叶绿素含量均显著下降幼苗叶片脯氨酸(Pro)含量表现为PEG15%>PEG10%>PEG5%,除PEG5%胁迫24 h处理与对照差异不显著外,其他处理均显著高于对照。幼苗叶片过氧化物酶POD活性表现为PEG15%>PEG10%>PEG5%,各处理POD活性均显著高于对照且各处理间差异显著,其中5%胁迫处理达最高。根系活力表现为PEG10%>PEG15%>PEG5%,PEG5%胁迫24、48、72 h处理均比对照显著增加,随后72h处理显著下降,24和48 h处理下降缓慢。[结论]可见,幼苗叶片相对含水量、叶绿色含量、Pro含量、POD活性和根系活力可以作为评价香蕉幼苗抗旱性的依据。
[Objective] The research aimed to explore the physiological response of Brazilian banana seedlings to PEG-6000 simulated drought. [Method] The seedlings of Musa AAA Cavendish subgroup cv.Brazil were used as materials to simulate the drought stress environment by PEG-6000. Three stress intensities (5%, 10%, 15%) and three stresses Duration (24,48,72 h) Changes in physiological indicators of Brazilian banana seedling under drought stress. [Result] Compared with the control, the relative water content and chlorophyll content of banana seedlings under different stress intensities and duration of stress were significantly decreased. The contents of Pro in leaves of seedlings were PEG15%> PEG10%> PEG5% The difference between treatment and control was not significant, other treatments were significantly higher than the control. POD activity of seedling leaves peroxidase showed PEG15%> PEG10%> PEG5%, POD activity of all treatments were significantly higher than the control and the difference was significant among the treatments, of which 5% of the stress treatment up to the highest. The activities of root system showed that PEG10%> PEG15%> PEG5% and PEG5% stress increased significantly at 24, 48 and 72 h, then decreased significantly at 72 h and decreased slowly at 24 and 48 h. [Conclusion] The relative water content, leaf green content, Pro content, POD activity and root vigor of seedling leaves could be used as the basis to evaluate the drought resistance of banana seedlings.