H_2O_2在黑松-松材线虫早期互作应答中的调控作用  

The Role of Hydrogen Peroxide During the Early Interactions Between Pinus thunbergii and Bursaphelenchus xylophilus

作　　者：俞禄珍[1] 吴小芹[1] 叶建仁[1] 张赛男[1] 

机构地区：[1]南京林业大学森林资源与环境学院,江苏省有害生物预防与控制重点实验室,南京210037

出　　处：《中国科学：生命科学》2013年第4期351-360,共10页Scientia Sinica(Vitae)

基　　金：国家自然科学基金(批准号:30972369);江苏省高校自然科学研究计划(批准号:11KJA22002);"十二五"国家科技支撑计划(批准号:2012BAD19B0703);江苏高校优势学科建设工程(PAPD)资助项目

摘　　要：松材线虫病已对中国森林资源以及生态环境造成严重破坏和威胁.近年信号分子H2O2在植物病害中的作用已成为研究热点,然而对松树-松材线虫互作中H2O2方面的功能研究不多见.本实验以三年生黑松(Pinus thunbergii)为材料,通过施用外源H2O2供给剂和抑制剂(AsA)探讨H2O2对松树-松材线虫互作体系中抗氧化保护酶、苯丙烷代谢途径的调控作用;同时对黑松感染松材线虫后体内H2O2产生的酶途径加以研究.结果表明,外源H2O2处理提前诱发了染虫黑松体内H2O2含量大幅度升高;AsA可在接种早期抑制染虫黑松体内H2O2含量,推迟了H2O2大量积累的发生.同步测定染虫黑松体内相关酶活性发现,外源H2O2处理后,染虫黑松体内APX和CAT活性下降幅度更大,MDA含量、PAL酶活性均提前积累;而外源AsA处理则推迟染虫黑松体内APX和CAT活性大幅下降的发生,延迟且削弱了MDA含量大量积累的发生和累积程度,PAL酶活性升高也滞后.同步观察黑松感病症状,发现H2O2处理组染虫黑松发病最快;仅接种松材线虫处理组次之;AsA处理组染虫黑松发病最慢.这表明,受松材线虫侵染后,黑松体内大量累积的信号分子H2O2可影响寄主体内抗氧化保护酶活性、苯丙烷代谢途径的表达,进一步影响了感病症状的表达.对黑松体内H2O2产生酶来源研究发现,黄嘌呤氧化酶(XO)抑制剂别嘌呤醇和NADPH氧化酶抑制剂二亚苯基碘(DPI)处理均能明显抑制黑松体内H2O2含量,说明XO和NADPH氧化酶均是黑松与松材线虫互作体系中内源H2O2合成的重要酶.Pine wilt disease has caused great damage to forest resource and ecological environment in China. Signaling molecule H202 has become a hot topic in plant disease in recent years, however rare research was in the pine wilt disease. In this experiment, three-year-old black pine （Pinus thunbergii） was pretreated with exogenous H202 dornors and inhibitors to investigate H202 possible regulation role of the antioxidant protective enzymes and the in the phenylpropanoid metabolic pathway in the p!ne-pine wood nematode interactions; in addition enzymatic sources of H202 was studied. The results showed that exogenous H202 dornors induced the increasing of H202 content earlier; exogenous H202 inhibitors AsA inhibited H202 content in pines in the early stage and delayed H202 accumulation. Simultaneous determination of the activity Of the enzyme showed that exogenous H202 treatment inhibited APX, CAT activity, meanwhile the content of MDA, PAL enzyme activity accumulated in advance; exogenous AsA treatment delayed decrease of the APX, CAT activity, delay and weaken the massive accumulation of MDA content occurred and the cumulative extent, PAL activity increased later. The observation of the black pine susceptible symptoms found that symptoms appeared earliest after H202 dornors treatment; AsA treatment appeared latest. This suggests that signaling molecule H：O2 through the regulation of antioxidant protective enzyme system and phenylpropanoid metabolic pathway mediated the responses of pine to the invasion of nematode. Enzymatic sources study found that xanthine oxidase（XO） inhibitor allopurinol, NADPH oxidase inhibitors two phenylene iodine（DPI）, could both inhibit H202 content, so XO and NADPH oxidase are responsible for endogenous H202 production.

关 键 词：松材线虫 黑松 过氧化氢 抗氧化酶 苯丙氨酸解氨酶 黄嘌呤氧化酶 

分 类 号：S763.7[农业科学—森林保护学]