摘要
以两年生‘王林’苹果为试材，研究了水杨酸（ＳＡ）对苹果叶片中过氧化氢（Ｈ２Ｏ２）水平的调节及其机制。结果表明，０．２５～１０．０ｍｍｏｌ·Ｌ－１ＳＡ能明显提高叶片中Ｈ２Ｏ２水平，其机制不仅在于ＳＡ抑制了过氧化氢酶（ＣＡＴ）活性，从而抑制了Ｈ２Ｏ２的降解使其积累，而且还由于ＳＡ提高了超氧化物歧化酶（ＳＯＤ）活性，促进了超氧阴离子（Ｏ－２）向Ｈ２Ｏ２的歧化反应，因而增加了Ｈ２Ｏ２的生成量。ＳＡ还诱导了特异的过氧化物酶（ＰＯＤ）同工酶。
Salicylic acid (SA) plays many roles in plants. It was suggested that one of the mechanisms by which SA induces plant disease resistance is that SA inhibits catalase (CAT) activity and thereby enhances the hydrogen peroxide (H 2O 2) level in tobacco. H 2O 2 has been considered as a second messenger in plants. To investigate the regulation of SA to H 2O 2 level and its mechanisms in apple leaves,the experiment was conducted to examine the effects of exogenous SA on the H 2O 2 content and its relationship with the activities of CAT,superoxide dismutase (SOD) and peroxidases (POD) in the leaves of apple trees ( Malus domestica Borkh. cv. Orin). The results showed that exogenous SA significantly increased H 2O 2 level in the leaves of apple when sprayed on the leaves at the concentrations of 0.25～10.0mmol·L -1 . In the meantime SA appeared to inhibit the CAT activity,increase SOD and POD activities and decrease superoxide anion (O - 2) level. Therefore it is suggested that SA increased H 2O 2 level in apple leves through both blocking the degradation of H 2O 2 by inhibiting CAT activity and enhancing H 2O 2 generation by increasing SOD activity. POD may be involved in the increase of H 2O 2 induced by SA.
出处
《园艺学报》
CAS
CSCD
北大核心
1997年第3期220-224,共5页
Acta Horticulturae Sinica
基金
国家自然科学基金
山东省自然科学基金
关键词
水杨酸
苹果树
过氧化氢
过氧化氢酶
Salicylic acid
Apple trees
Hydrogen peroxide
Catalase
Superoxide dismutase
