摘要
【目的】枯萎病在广东省荸荠产区普遍发生,严重影响荸荠产量。探明荸荠枯萎病病原菌种类和生物学特性,对该病害防治有重要意义。【方法】2022—2024年自广东韶关乐昌采集病害样本,用组织分离法分离病原菌,基于病原菌致病性、形态和分子生物学特征确定其分类地位,采用菌丝生长法测定温度、pH、光照、碳源和氮源对病原菌菌丝生长的影响。【结果】分离获得形态特征基本一致的34株镰刀菌,在PDA培养基上,菌落呈白色;产孢细胞瓶梗状,长度为8.46~55.65µm;小型分生孢子较多,卵形或纺锤形,大小4.22~12.65µm×2.24~3.82µm,在产孢细胞顶端聚集成假头状;大型分生孢子镰刀形,稍弯,向两端逐渐变尖,有3~5个隔膜,大小为18.24~36.40µm×2.92~4.50µm;厚垣孢子球形,直径为7.85~12.32µm。盆栽回接试验结果表明,分离菌株对荸荠具有致病性。基于于EF-1α、RPB2和TUB基因序列构建系统发育树,发现病原菌与共享镰刀菌Fusarium commune聚为一支,与尖孢镰刀菌F.oxysporum明确区分,特异性引物扩增结果也证明分离菌株为F.commune。病原菌适宜生长温度为26~30℃,适宜pH为7~8,碳源麦芽糖、有机氮源牛肉浸粉、酵母提取物和蛋白胨均利于菌丝生长,28℃黑暗培养120 h后菌落直径均达60 mm左右。【结论】明确引起广东韶关乐昌荸荠枯萎病的病原菌为F.commune,研究结果可为病害防治提供依据。
【Objective】Fusarium wilt is prevalent in Chinese water chestnut producing regions of Guangdong Province,severely impacting crop yields.Identifying the pathogen and analyzing its biological characteristics is of significant importance for the effective management of the disease.【Method】Diseased samples were collected from Lechang,Shaoguan,between 2022 and 2024.Strains were isolated using the tissue isolation method.Their taxonomic status was determined based on pathogenicity,morphological characteristics and molecular biological features.The effects of temperature,pH,light,carbon and nitrogen source on the pathogens were measured by mycelium growth method.【Result】34 Fusarium spp.isolates with similar morphological characteristics were obtained.The colony was white on PDA medium.Conidiogenous cells were phialidic,8.46~55.65µm in length.Microconidia were abundant,oval or spindle-shaped,4.22~12.65µm×2.24~3.82µm,and borne false heads from phialides.Macroconidia were falcate,slightly curved,tapering apically with 3 to 5 septa,and 18.24~36.40µm×2.92~4.50µm.Chlamydospores were spherical,7.85~12.32µm in diameter.Pot experiments confirmed their pathogenicity to Chinese water chestnut.The phylogenetic trees constructed using combined sequences of the EF-1α,RPB2 and TUB revealed the pathogens clustered with Fusarium commune strains and distinctly differentiated from F.oxysporum.Specific primers amplification further confirmed the pathogens belonged to F.commune.The suitable temperature for mycelium growth of F.commune was 26~30℃,and the suitable pH was 7~8.Carbon source maltose,organic nitrogen source beef extract powder,yeast extract and tryptone were beneficial to mycelium growth,colony diameters reached approximately 60 mm after 120 h incubation at 28℃in dark.【Conclusion】The study identified F.commune as the causative agent of Chinese water chestnut wilt in Guangdong,providing critical insights for disease control strategies.
作者
沈会芳
张景欣
蒲小明
杨祁云
孙大元
刘平平
SHEN Huifang;ZHANG Jingxin;PU Xiaoming;YANG Qiyun;SUN Dayuan;LIU Pingping(Institute of Plant Protection,Guangdong Academy of Agricultural Sciences/Guangdong Key Laboratory of New Technique for Plant protection,Guangzhou 510640,China)
出处
《广东农业科学》
2025年第6期99-109,共11页
Guangdong Agricultural Sciences
基金
国家重点研发计划项目(2024YFD1701202)
广东省烟草专卖局科技项目(201908)。
关键词
荸荠
枯萎病
病原鉴定
共享镰刀菌
尖孢镰刀菌
生物学特性
Chinese water chestnut
Fusarium wilt
pathogen identification
Fusarium commune
Fusarium oxysporum
biological characteristics
