莲藕腐败病导致藕节组织结构变异的显微观察研究  

Histopathological assessment on the lotus rhizome tissue infected by Fusarium spp.causing lotus rhizome rot

作　　者：滕辉 杨继硕 李思雨 周冬梅[2] 王楠 孙树艳 刘华琪 魏利辉 王云鹏[1] 邓晟 TENG Hui;YANG Jishuo;LI Siyu;ZHOU Dongmei;WANG Nan;SUN ShuYan;LIU Huaqi;WEI Lihui;WANG Yunpeng;DENG Sheng(School of Life Science and Food Engineering,Huaiyin Institute of Technology,Huaian 223001,China;Institute of Plant Protection,Jiangsu Academy of Agricultural Sciences,Nanjing 210014,China;Nanjing Bostec Bioengineering Co.,Ltd,Nanjing 210019,China)

机构地区：[1]淮阴工学院生命科学与食品工程学院,江苏淮安223003 [2]江苏省农业科学院植物保护研究所,江苏南京210014 [3]南京百特生物工程有限公司,江苏南京210019

出　　处：《植物病理学报》2024年第1期82-91,共10页Acta Phytopathologica Sinica

基　　金：财政部和农业农村部:国家现代农业产业技术体系资助(CARS-24-C-01);江苏省自主创新资金项目【CX(22)3022】。

摘　　要：莲藕是我国栽培面积最大、最重要的水生蔬菜。随着种植规模的扩大及栽培制度和栽培方式的单一化,莲藕病害问题日趋严重,其中莲藕腐败病危害最大也最难防治。目前国内外对镰刀菌引起莲藕腐败病致病机理方面的研究较少,本研究基于莲藕地下茎的发病症状,从微观和超显微层面揭示病害发生后地下茎及其维管束组织的变化。石蜡组织切片观察表明,随着病程的发展,发病组织会出现越来越多的被甲苯胺蓝染成深色的坏死细胞,而且这些细胞围绕维管束出现,越靠近维管束其数量越多,分布越密集。为了进一步揭示病原菌侵染对维管束的影响,本研究又利用光学显微镜和扫描电子显微镜对病藕藕丝进行观察,结果表明,随着病变程度加深,藕丝表面原本光滑紧凑的结构变得粗糙松散,且表面附着大量瘤状凸起物以及其它可能的代谢附着物。这些变化势必影响维管束内水分和养分的疏导,最终造成植株地上部分表现失水萎蔫的症状。本研究结果揭示了病害症状发生的细胞生物学机制,并为今后抗性品种的选育提供理论依据。Lotus is the most important aquatic vegetable in China and has the largest cultivation area.With the expansion of cultivation and the simplification of agricultural practices,various lotus diseases have been becom-ing more serious,among which lotus rhizome rot disease is the most harmful and the most difficult to control.At present,there are few research reports on the pathogenesis of Fusarium spp.causing lotus rhizome rot disease around the world.From the microscopic and ultra-microscopic levels,this study revealed the changes to the rhi-zome and its vascular tissues during Fusarium infection.The observation of paraffin-embedded tissue sections showed that with the development of the disease,necrotic cells stained by toluidine blue appeared around the vascular bundles,and the closer to the bundles,the more numerous necrotic cells and the more densely distribu-ted.In order to further reveal the influence of pathogen infection on vascular bundles,brightfield optical and scanning electron microscopy were used to observe the lotus fibers in the diseased lotus rhizomes.The results showed that the smooth and compact lotus fibers became rough and dispersed with the disease tending to be more severe,and a large number of galls-like protrusions and other possible metabolic attachments were attached to the surface.These changes to the vascular bundles are likely to reduce the water and nutrient transportation,and finally the aboveground parts of the plant exhibited the symptoms of water loss and wilting.The results of this study revealed the cellular biological mechanism of the disease symptom development,and provided a basis of histology for the breeding of resistant varieties in the future.

关 键 词：莲藕腐败病 镰刀菌 致病机理 组织学 扫描电子显微镜 莲藕丝 

分 类 号：S432.44[农业科学—植物病理学]