水杨酸对缓解葡萄苗铝毒害的生理机制

摘要

In order to study the physiological mechanism of salicylic acid on alleviating aluminum toxicity of grape seedlings ,solve the problem of aluminum toxicity in acid soil .Shuijing grape as material , using hydroponic method,in addition to the culture medium of 0.4 mmol/L aluminum chloride and different concentrations of salicyl-ic acid were co-cultured for 5 weeks,after determination the indices of root ,stem and leaf growth status ,chlorophyll content ,and active oxygen scavenging system and membrane lipid peroxidation of leaf and root .Effects of salicylic acid on the growth physiology of grape seedlings were analyzed under aluminum stress .The results show that under aluminum stress,plant growth was inhibited,leaf yellowing new leaves,root black.Chlorophyll content increased in old leaves and decreased in new leaves .SOD,POD and MDA contents increased in leaf and root and oxygen free radical production rate also increased ,while root activity decreased .25 ,50 μmol/L salicylic acid treatment signifi-cantly promoted the growth of grape seedling shoot stem ,root color reddish ,but 100 μmol/L salicylic acid treatment could inhibit the growth of grape seedlings ,a small amount of root black .Salicylic acid treatment on the physiologi-cal effects of alleviate aluminum toxicity was obviously in grape seedlings .25 ,50 μmol/L Salicylic acid treatment made chlorophyll and carotenoid contents were significantly higher than that of CK and single aluminum stress in old leaves,and the contents were significantly lower than single aluminum treatment .The SOD and POD activity in leaf and root were lower than single aluminum treatment ,wheras the root POD activity was significantly higher .Produc-tion rate of oxygen free radical and malondialdehyde content treatment were lower than the single aluminum in leaf and root.In addition,50 μmol/L salicylic acid treatment also significantly increased root vigor under aluminum stress.Thus,aluminum stress inhibition on the growth of grape plant significantly ,showed strong poison ,while sali-cylic acid treatment ,had a certain effect on the remission of grape aluminum toxicity ,among which 50μmol/L sali-cylic acid treatment to the most obvious physiological effects alleviated aluminum toxicity in grape seedlings .%为了探明水杨酸对缓解葡萄苗铝毒害的生理机制，解决葡萄在酸性土壤中发生铝毒害的问题。以水晶葡萄为材料，采用水培的方法，在培养液中加入0．4 mmol／L氯化铝和不同浓度的水杨酸共培养5周，之后测定葡萄根系、茎干和叶片的生长状况、叶绿素含量、叶片和根系的活性氧清除系统及膜脂过氧化等指标，分析铝胁迫下水杨酸对葡萄苗生长及生理的影响。结果表明，铝胁迫下，葡萄植株生长受抑，嫩叶黄化，根系变黑；老叶叶绿素含量上升，嫩叶叶绿素含量下降；叶片和根系的SOD、POD活性和MDA含量上升，氧自由基产生速率也上升，而根系活力则下降。25，50μmol／L水杨酸处理明显促进了葡萄苗枝干的生长，根系颜色为微红色，但100μmol／L水杨酸处理却明显抑制了葡萄苗的生长，有少量根系变黑。水杨酸处理对葡萄苗缓解铝毒害的生理效应明显，25和50μmol／L水杨酸使老叶叶绿素和类胡萝卜素含量显著高于CK和单独铝胁迫，使嫩叶叶绿素a、叶绿素a＋b和类胡萝卜素含量比单独铝处理显著升高，水杨酸处理使叶片的SOD、POD活性和根系的SOD活性低于单独铝处理，而根系POD活性显著高于单独铝处理，叶片和根系氧自由基产生速率和丙二醛含量比单独铝处理有所下降；此外，50μmol／L水杨酸处理还显著提高了铝胁迫下的根系活力。可见，铝胁迫对葡萄植株生长的抑制作用明显，表现出较大的毒害作用，而水杨酸处理对缓解葡萄铝毒害具有一定的效果，其中以50μmol／L水杨酸处理对缓解葡萄苗铝毒害的生理效应最明显。