FOC-RA-5诱导后黄瓜叶片内几种酶活性的变化

Change of Several Enzymes Activity in Leaf of Cucumber After Inducted With FOC-RA-5

用致病力为0的FOC-RA-5在黄瓜胚根长约1cm(浸胚根)和子叶展平时(灌根)分别进行2次诱导处理,以无菌水处理为对照,诱导处理后每隔24h取黄瓜叶片作为供试材料,对黄瓜叶片内苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)、过氧化物酶(POD)、脂氧合酶(LOX)、抗坏血酸过氧化物酶(APX)和硝酸还原酶(NR)活性进行测定,研究了黄瓜枯萎病菌弱毒菌株对黄瓜枯萎病诱导抗性机理。结果表明:叶片内LOX、PAL、PPO、POD活性先升高后降低,APX、NR活性先降低后升高,处理组的酶活性显著高于对照组的酶活性;黄瓜叶片内APX、LOX、PPO、POD和PAL活性与诱导后黄瓜植株的病情指数呈负相关,NR活性与诱导后黄瓜植株病情指数呈正相关。

It was conducted that germinated seed of cucumber at the time of radicle length of about 1cm（soaking the radicle）and the cotyledons flattened（root irrigation）were induced two times with the pathogenicity of 0FOC-RA-5,that treated with sterile water as the control.After that,the leaves were randomly selected as the test materials every24 hours.These materials were used to measure cucumber phenylalanine ammonia lyase（PAL）,polyphenol oxidase（PPO）,peroxidase（POD）,lipid peroxidation（LOX）,ascorbate peroxidase（APX）and nitrate reductase（NR）activity in order to study the mechanism of resistance,which refered to the attenuated strain of cucumber against Fusarium wilt of cucumber.The results showed that the activity of enzymes LOX,PPO,PAL and POD in leaf increased at first and then decreased.The activity of enzymes NR and APX decreased at first and then increased.Enzyme activity in leaf of treated group was significantly higher than that of control group.The activity of enzymes APX,LOX,PAL,PPO,POD in leaf was negatively correlated with disease index of the induced plants.The activity of enzymes NR in leaf was positively correlated with disease index of the induced plants.