多核和双核丝核菌侵染水稻过程中细胞超微结构变化及细胞壁降解酶活性的差异  

The Difference of Ultrastructural Changes of Cells and Cell Wall Degrading Enzyme Activity of Multinucleate and Binucleate Isolates of Rhizoctonia spp.During Infection Process

作　　者：魏松红[1] 段淯 张优[1] 张照茹 李昕洋 刘伟 王海宁[1] WEI Song-hong;DUAN Yu;ZHANG You;ZHANG Zhao-ru;LI Xin-yang;LIU Wei;WANG Hai-ning(College of Plant Protection,Shenyang Agricultural University,Shenyang 110161,China)

机构地区：[1]沈阳农业大学植物保护学院,沈阳110161

出　　处：《沈阳农业大学学报》2021年第5期604-610,共7页Journal of Shenyang Agricultural University

基　　金：现代农业产业技术体系建设专项资金资助项目(CARS-01-37);辽宁省科学研究经费项目(LSNZD201902)。

摘　　要：丝核菌属真菌是重要的植物病原真菌,多种丝核菌种类及融合群可侵染水稻,不同丝核菌种类及融合群间致病力具有较大差异,分析不同丝核菌致病力差异对于研究丝核菌属病原菌导致的水稻病害的发生流行以及种群动态具有重要意义。为探究多核和双核丝核菌对水稻致病力差异产生的原因,采用扫描电子显微镜和透射电子显微镜对2种病原菌侵染水稻叶片细胞的超微结构进行观察,利用3,5-二硝基水杨酸法和实时荧光定量PCR技术对其侵染过程中产生的多聚半乳糖醛酸酶(PG)、果胶甲基半乳糖醛酸酶(PMG)、纤维素酶(Cx)、多聚半乳糖醛酸反式消除酶(PGTE)和果胶甲基反式消除酶(PMTE)的活性差异和多聚半乳糖醛酸酶基因(PG基因)的表达差异进行分析。结果表明:多核菌株菌丝扩展速度与形成侵染结构的数量均显著高于双核菌株。侵染24h时,多核菌株在水稻叶片表面形成较多侵染垫,双核菌株形成的侵染垫数量明显少于多核菌株;侵染48h时,多核菌株侵染的水稻叶片细胞叶绿体解体,而双核菌株侵染的水稻叶片细胞无明显变化。多核菌株与双核菌株在侵染水稻时均能产生5种细胞壁降解酶,且多核菌株细胞壁降解酶活性均显著高于双核菌株。PG酶活性显著高于其他4种细胞壁降解酶活性,多核菌株PG酶活性最高为860.46U·mg^(-1),双核菌株PG酶活性最高为59.27U·mg^(-1)。水稻纹枯病菌多核与双核菌株侵染水稻叶片过程中其PG基因表达趋势相同,但多核菌株PG基因表达量显著高于双核菌株,多核菌株侵染水稻24h时PG基因表达量达到最高,双核菌株在侵染水稻48h时PG基因表达量达到最高。研究结果可为进一步了解丝核菌属真菌的致病机制奠定理论基础。Rhizoctonia genus were important phytopathogenic fungi,and a range of Rhizoctonia species and anastomosis groups could infect rice.The pathogenicity of different Rhizoctonia species and anastomosis groups had a great difference.It is important to analyze the difference of pathogenicity of different Rhizoctonia species and anastomosis groups to study the occurrence,prevalence and population dynamics of rice diseases caused by Rhizoctonia genus.In order to explore the difference in pathogenicity between multinucleate isolates and binucleate isolates of Rhizoctonia spp.,in this study,the scanning electron microscope and transmission electron microscope were used to observe the ultrastructure of the two pathogens infecting rice leaves,and the 3,5-dinitrosalicylic acid method and qRT-PCR technique were used to analyze the activities of polygalacturonase(PG),pectin methylgalacturonidase(PMG),cellulase(Cx),polygalacturonate trans eliminase(PGTE),pectin methyl trans eliminase(PMTE)and the expression of the polygalacturonase gene(PG gene).The results showed that the hyphae expansion rate and the number of infection structures of multinucleate isolates were significantly higher than those of binucleate isolates during the infection process.At 24h of infection,multinucleate isolates formed more infection structures on the surface of rice leaves,while the number of infection structures formed by binucleate isolates were significantly less than that of multinucleate isolates.At 48h of infection,the chloroplasts of rice leaf cells infected by multinucleate isolates disintegrated,while the organelles of rice leaf cells infected by binucleate isolates did not change significantly.Both multinucleate and binucleate isolates could produce five cell wall degrading enzymes when they infected rice,and the activity of cell wall degrading enzymes of multinucleate isolates was significantly higher than those of binucleate isolates.The PG enzyme activity was significantly higher than the other four cell wall degrading enzyme activities.Th

关 键 词：水稻纹枯病菌 多核菌株 双核菌株 侵染结构 细胞壁降解酶 PG基因 

分 类 号：S435.111[农业科学—农业昆虫与害虫防治]