PEG胁迫下Ca2+和钙调素拮抗剂W7对不同品种番茄幼苗抗氧化系统的影响

以耐旱性不同的2个番茄品种为试材,采用营养液水培法,研究了钙、钙调素拮抗剂W7N-(6-aminohexyl) -5-chloro-1-naphthalene sulfonami de]预处理对聚乙二醇模拟干旱胁迫下番茄幼苗抗氧化系统的影响.结果表明,钙调素拮抗剂W7浸种处理显著提高了番茄幼苗丙二醛(MDA)、H2O2含量和O2 ()/(*)]产生速率,抑制了超氧化物歧化酶(SOD)、过氧化物酶(POD)活性,加剧了抗坏血酸(A sA)和还原型谷胱甘肽(GSH)的破坏;而Ca 2+处理显著降低了PEG胁迫下番茄幼苗MDA 、H2O2含量和O2 ()/(*)产生速率,提高了SOD、POD活性,减轻了胁迫对AsA和GSH的破坏.相同处理条件下,耐旱性强的品种'毛粉802'较耐旱性弱的品种'皇冠'伤害程度轻,Ca 2+-CaM信号系统对缓解番茄PEG胁迫具有重要作用.

Effects of calcium and calmodulin antagonist W7 on antioxidant systems of roots of tomato seedlings under drought stress

The effect of Ca 2+ and calmodulin antagonist W7 on antioxidant systems of tomato (Lycopersicon esculentum M.) seedlings under drought stress induced by 10% polyethylene glycol (PEG-6000) was studied i n hydroponics culture. The results showed that pretreated seedlings with calmodul in antagonist W7 under PEG stress had lower SOD and POD activities, and higher p roduction rate of O2 ()/(*), MDA and H2O2, in addition, ag gravated the dam age of AsA and GSH; On the contrary, Ca 2+ treatment enabled the seedli ngs to keep relatively high activities of SOD and POD, lower production rate of O 2-* and MDA content, at the same time, alleviated the accumulation of AsA a nd GSH. These results indicated that Ca 2+-CaM signal transduction might re gulate resistance of tomato seedlings to PEG stress of tomato seedlings by affec ting the activity of some antioxidant enzymes and the content of antioxidant sub stance. The experiment shows that Ca 2+-CaM signal system plays an importan t regulating role in alleviating PEG stress induced by 10% polyethylene glycol ( PEG-6000) in seedlings.