接种枯萎病菌对甜瓜木质素合成相关酶活性及CmCADs表达的影响  

Effects of Fusarium oxysporum f. sp. melonis on Lignin, Activities of Lingin-Related Enzymes and Genes Expressions of CmCADs in Oriental Melon(Cucumis melo var. makuwa Makino)

作　　者：刘贺娟[1] 李悦鹏 刘威[1] 邵琪[1] 齐红岩[1] 

机构地区：[1]沈阳农业大学园艺学院/设施园艺省部共建教育部重点实验室/环渤海湾地区设施蔬菜优质高效生产协同创新中心,沈阳110866

出　　处：《中国农业科学》2016年第11期2153-2163,共11页Scientia Agricultura Sinica

基　　金：国家现代农业产业技术体系建设专项(Nycytx-35-gw23);辽宁省高等学校优秀人才支持计划(LR2014020)

摘　　要：【目的】明确接种枯萎病菌对甜瓜幼苗植株表型、木质素含量、木质素合成相关酶活性及肉桂醇脱氢酶(cinnamy alcohol dehydrogenase,CAD)基因表达的影响,找出响应枯萎病菌的CmCADs成员。【方法】选用抗枯萎病品种薄皮甜瓜‘彩虹7号’为试验材料。在甜瓜幼苗长至"三叶一心"时接种枯萎病菌-尖孢镰刀菌(Fusarium oxysporum f.sp.melonis)。以长势相同的健康植株浇灌等量无菌水为对照。在接种后0、1、3、5、7和9 d观察甜瓜植株表型变化,并测定其营养器官中的木质素含量、木质素合成关键酶(苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)和CAD)活性及CmCADs的表达量。【结果】接种枯萎病菌后,甜瓜植株表型发生明显变化。在接种枯萎病菌后5 d甜瓜植株叶片出现轻微萎蔫,接种后9 d植株全部叶片均已萎蔫。甜瓜营养器官中木质素含量及木质素合成相关酶PAL、POD和CAD活性在接种枯萎病菌后与对照相比均有不同程度的升高。其中木质素含量在根、茎和叶中呈现出一致的变化趋势,即木质素含量均随着接种枯萎病菌后天数的延长而增加,且显著高于对照。PAL活性在甜瓜根和茎中呈现先升高后下降的变化趋势,在叶片中整体呈现升高的趋势且显著高于对照。POD活性在各时期均高于对照并呈现出不同的变化趋势。CAD活性在甜瓜根、茎、叶中变化趋势一致,均呈现先升高后下降的趋势。接种枯萎病菌后,CmCADs各成员在甜瓜营养器官中的表达表现出组织特异性。根中除Cm CAD4外,其他4个成员均在接种后7 d受强烈诱导。茎中各成员均无表达,而叶中Cm CAD2和Cm CAD5在接种后5 d受到强烈诱导。【结论】与对照相比,甜瓜营养器官中木质素含量及木质素合成相关酶PAL、POD和CAD活性在接种后均升高,表明木质素合成途径可能在甜瓜抵御枯萎病中起重要作用,根和叶中均受枯萎病菌诱导表达的Cm CAD2和Cm CAD5�【Objective】The purpose of this study is to investigate the effects of Fusarium oxysporum on symptom, lignin content, activities of lignin-related enzymes and real-time fluorescent quantitative PCR analysis of CmCADs gene expression of CmCADs in oriental melon seedlings and to find out the gene family members of CmCADs that can respond to the Fusarium oxysporum. 【Method】The oriental melon ‘Caihong 7＇ which is resistant to Fusarium oxysporum was used as experimental materials. Then the melon seedlings were inoculated with F. oxysporum at 3 true leaves stage. The control plants were dealt with equivalent sterile water. The changes of phenotype were observed and lignin content, activities of lingin-related enzymes（PAL, POD and CAD） and genes expressions of CmCADs in the vegetative organs of oriental melon seedlings were determined at 0, 1, 3, 5, 7 and 9 days after inoculation.【Result】The symptom of oriental melon seedlings showed obvious changes. The leaves began to wilt slightly 5 days after inoculation and wilt badly 9 days after inoculation. The results showed that compared with the control, the lignin content and the activities of lignin-related enzymes were all increased to a certain extent. The change trend of lignin content in roots, stems and leaves was basically identical with keeping increasing and higher than the control treatment. The activities of PAL which increased first and then decreased in roots and stems while exhibited a global increased trend in the leaves were obviously higher than the control treatment. The activities of POD presented different changes with higher activities than control in each period. The activities of CAD presented a trend of earlier increase and later decrease in roots, stems and leaves. In the study, CmCADs showed tissue-specific expression after inoculation. Cm CAD1, Cm CAD 2, Cm CAD 3 and Cm CAD 5 were strongly induced in roots 7 days after inoculation, except Cm CAD4, while only Cm CAD2 and Cm CAD5 in leaves were induced strongly 5 days after inocula

关 键 词：薄皮甜瓜 枯萎病 木质素 肉桂醇脱氢酶 基因表达 

分 类 号：S436.5[农业科学—农业昆虫与害虫防治]