不同抗性甜瓜接种蔓枯病菌后PAL、PPO与POD活性的变化  

Changes of PAL, PPO and POD activites in melon with different resistances after inoculated with Didymella bryoniae

作　　者：张宁[1] 毕研飞 郭静[1] 徐兵划 钱春桃[1] 陈劲枫[1] 

机构地区：[1]南京农业大学园艺学院作物遗传与种质创新国家重点实验室,南京210095

出　　处：《植物生理学报》2016年第8期1169-1175,共7页Plant Physiology Journal

基　　金：国家自然科学基金新疆联合基金项目(U1178307)~~

摘　　要：本文以2份甜瓜单基因抗源PI157082和PI482398、聚合基因材料082-398以及‘白皮脆’为试验材料,用3种不同浓度(5×10~5、5×10~7和5×10~9个·mL^(-1))的蔓枯病菌处理,研究并分析在不同浓度蔓枯病病原菌胁迫下甜瓜的抗病表现以及3种内源防御酶苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)及过氧化物酶(POD)活性的变化。结果表明:甜瓜蔓枯病菌液浓度为5×10~7个·mL^(-1)时,可以区分聚合基因抗源和单基因抗源对蔓枯病抗性能力的差异,聚合基因抗源在菌液浓度为5×10~9个·mL^(-1)时依然能够抗病。3种防御酶PAL、PPO和POD与甜瓜对蔓枯病的抗性关系非常密切。甜瓜受蔓枯病菌侵染后,防御酶活性比对照明显增高,聚合基因材料酶活性增幅和峰值均高于单基因抗源,单基因抗源活性增幅和峰值均高于感病甜瓜。PAL和PPO在接种后第4~5天活性上升最快,并且在此阶段达到峰值,而POD在中后期仍然保持活性上升的状态。这说明,单一抗性基因的聚合在一定程度上可以提高甜瓜对蔓枯病的抗性,3种防御酶的活性变化可以为鉴定甜瓜蔓枯病早期抗性提供参考。To investigate the disease resistance and the dynamic activities of endogenous defense enzymes, phenylalanine ammonia lyase（PAL）, polyphenol oxidase（PPO） and peroxidase（POD）, induced by different concentrations of melon gummy stem blight（GSB） pathogens, two monogenic resistance sources（PI157082 and PI482398）, one pyramided genes source（082-398） and ‘Baipicui＇ were employed as the study materials. The results showed that the difference in resistance between single-gene and the pyramided genes sources could be distinguished when the spores concentration was 5×10^7 spores·mL-1. The pyramided genes source could still be resistant to high spore concentration. There is a very close relationship between the three defense enzymes and GSB resistance of melon. After infected by GSB, the activities of three defense enzymes were significantly higher than the control. Furthermore, the increasing rates and peaks of pyramided genes material were higher than those in the single-gene resistance sources and susceptible melon. The increasing rates of PAL and PPO activities were the fastest at 4 to 5 days after inoculation. In addition, the activities of PAL and PPO reached the peak at this stage as well, however, the activity of POD still was increasing in the middle and late period. This study showed that pyramiding the single resistance genes can enhance the resistance to GSB of melon to some extent. The activities of three defense enzymes could provide a reference for the early identification of the resistance to GSB in various resistance melon.

关 键 词：甜瓜 蔓枯病 聚合基因 抗性鉴定 防御酶 

分 类 号：S436.5[农业科学—农业昆虫与害虫防治]