油菜防御酶系对芸薹根肿菌毒素诱导的响应

Response of Rape Defense Enzymes on the Induction of Plasmodiophora Brassicae Toxin

为探讨油菜防御酶系对芸薹根肿菌毒素诱导的响应,分别用不同体积分数(10%,25%,50%,85%,100%)的芸薹根肿菌粗毒素处理油菜幼苗,测定其对油菜叶片内过氧化物酶(POD)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、多酚氧化酶(PPO)和苯丙氨酸解氨酶(PAL)活性的影响.结果表明,经毒素处理一定时间,POD、SOD和PPO活性均有不同程度提高,且高浓度毒素处理的酶活呈先升后降的趋势;其中POD活性在48 h时达到最大值,为对照的4.20倍;SOD和PPO活性均在72 h时达到最大值,分别为对照的1.83和7.00倍;CAT和PAL活性呈先降后升的趋势,二者均在72 h时出现活性最高峰,分别为对照的3.52和6.75倍.本试验表明,根肿菌粗毒素可诱导提高油菜叶片5种防御酶活性抵抗毒素的侵害.

To study the responses of rape defense enzymes to Plasmodiophora brassicae toxin induction,the influences of treating the rape seedlings with different concentrations（ 10%,25%,50%,85%,100%） of Plasmodiophora brassicae crude toxin on the activity changes of peroxidase（ POD）,catalase（ CAT）,superoxide dismutase（ SOD）,polyphenol oxidase（ PPO） and phenylalanine ammonia lyase（ PAL） in leaves of rape were detected in this study. The results showed that the activities of POD,SOD and PPO in the treated rape leaves all increased at different degrees and the enzyme activities firstly asended,then decreased after being treated by high concentration toxin. The activity of POD reached the highest value at 48 h and was 4. 2 times of the control. Activities of SOD and PPO reached the maximal level at 72 h,with the activities were 1. 83 and 7. 00 times of the control. Activities of CAT and PAL decreased at the beginning then increased,activity of both enzymes reached the peaks at 72 h,with the activities were 3. 52 and 6. 75 times of the control. Therefore,Plasmodiophora brassicae crude toxin plays an important role on inducting toxin resistance by increasing activities of five kinds of defense enzymes in rape leaves.