柑橘采后生理代谢对胶孢炭疽菌粗毒素的动态响应  

Dynamic Response of Physiological Metabolism in Postharvest Citrus to Crude Toxin from Colletotrichum gloeosporioides

作　　者：黄小兰[1] 王日葵[1,2] 韩冷[1,2] 贺明阳[1,2] 周炼[1,2] HUANG Xiaolan;WANG Rikui;HAN Leng;HE Mingyang;ZHOU Lian(Citrus Research Institute, Southwest University, Chongqing 400712, China;National Citrus Engineering Research Center, Chongqing 400712, China)

机构地区：[1]西南大学柑桔研究所,重庆400712 [2]国家柑桔工程技术研究中心,重庆400712

出　　处：《食品科学》2017年第7期247-252,共6页Food Science

基　　金：重庆市科技计划项目(cstc2016shms-ztzx80005);国家科技支撑计划项目(2015BAD16B07)

摘　　要：目的:探究胶孢炭疽菌毒素对柑橘生理代谢的动态影响,为研究胶孢炭疽菌的致病机理提供理论参考。方法:在有机溶剂浸提法获得胶孢炭疽菌粗毒素的基础上,采用针刺接种法进行毒素的生物测定,分析粗毒素和病原菌对柑橘采后生理代谢(总酚、类黄酮含量;过氧化物酶(peroxidase,POD)、多酚氧化酶(polyphenol oxidase,PPO)、超氧化物歧化酶(superoxide dismutase,SOD)、苯丙氨酸解氨酶(phenylalanine ammonialyase,PAL)、β-1,3-葡聚糖酶(β-1,3-glucanase,GLU)活性;丙二醛(malondialdehyde,MDA)、果皮细胞壁成分含量)的动态影响。结果:胶孢炭疽菌粗毒素能使柑橘果实产生典型的病斑症状,且使MDA含量显著增高,细胞壁成分含量降低。当毒素浓度较低时,果实病斑直径与PPO活性、POD活性、类黄酮以及木质素含量呈正相关;与纤维素、半纤维素和果胶含量呈负相关。毒素浓度增高时,果实机体及防御酶系统遭到破坏,酶活性急剧下降。结论:胶孢炭疽菌粗毒素能影响柑橘果实生理代谢,引起果实发病,最终导致病斑的形成。由此证明毒素在胶孢炭疽菌对柑橘的致病过程中起到重要作用。Objective:The dynamic response of physiological metabolism in postharvest citrus to toxin from Colletotrichum loeosporioides was studied to obtain a better understanding of the interaction between citrus and C.gloeosporioides.Methods:The crude toxin was isolated by organic solvent extraction,and its bioassay was performed by the acupuncture ethod in postharvest citrus.Moreover,the dynamic effects of the crude toxin and pathogenic bacteria on physiological etabolism of citrus fruits in terms of the contents of phenols,flavonoids,and malondialdehyde(MDA),cell wall omponents in citrus peel and the activities of polyphenol oxidase(PPO),peroxidase(POD),superoxide dismutase(SOD),phenylalanine ammonialyase(PAL),andβ-1,3-glucanase(GLU)were analyzed.Results:Typical lesion caused by the toxin as observed,and the content of MDA was significantly increased,while the content of cell wall compounds was decreased.Upon treatment with the crude toixn at a low concentration,there was a positive correlation of lesion diameter with the ontent of flavonoids,lignin and the activities of PPO and POD,whereas a negative correlation existed between cell wall ompounds and lesion diameter.However,the defense enzyme system and citrus fruits were damaged by the crude toxin at high concentration,causing a dramatic decrease in the enzyme activities.Conclusion:Physiological metabolism of citrus ruits can be influenced by the crude toxin of C.gloeosporioides,and thus it plays an important role in the pathogenicity of.gloeosporioides.

关 键 词：炭疽菌 毒素 生理代谢 柑橘 

分 类 号：TS201.3[轻工技术与工程—食品科学]