广东省木榄炭疽病病原菌鉴定及其拮抗细菌筛选  

Identification of Colletotrichum fructicola Causing Anthracnose on Bruguiera gymnorhiza and Screening of its Antagonistic Bacteria in Guangdong Province

作　　者：袁永强 周舜 米仁军 潘继东 邓小大 辛琨 蔡书静 王福生 饶雪琴[1] Waqar Ahmed 王新荣[1] YUAN Yong-qiang;ZHOU Shun;MI Ren-jun;PAN Ji-dong;DENG Xiao-da;XIN Kun;CAI Shu-jing;WANG Fu-sheng;RAO Xue-qin;Waqar Ahmed;WANG Xin-rong(College of Plant Protection,Guangdong Province Key Laboratory of Microbial Signals and Disease Control,South China Agricultural University,Guangzhou 510642,Guangdong,China;Forestry Bureau of Chenxi County,Huaihua 419500,Hunan,China;Chinese Academy of Forestry,Research Institute of Tropical Forestry,Guangzhou 510642,Guangdong,China)

机构地区：[1]华南农业大学植物保护学院,广东省微生物信号与作物病害防控重点实验室,广东广州510642 [2]湖南省辰溪县林业局,湖南怀化419500 [3]中国林业科学研究院,热带林业研究所,广东广州510520

出　　处：《林业科学研究》2025年第2期185-195,共11页Forest Research

基　　金：广东省重点领域计划研究项目;广东省红树林生态修复和功能提升技术研究与示范(2020B020214001)。

摘　　要：[目的]]明确引起广东省湛江市木榄炭疽病的病原菌,揭示病原菌生物学特性,并筛选拮抗菌,为该病的防控提供依据。[方法]采用组织分离法和单孢分离法进行病原分离纯化,通过形态学和多基因系统发育分析(ITS-TUB2-ACT-GAPDH)相结合的方法对分离菌株进行鉴定,通过人工接种测定其致病性。用菌丝生长速率法和产孢量法研究其生长特性;利用平板对峙法进行拮抗菌的筛选。[结果]28℃条件下,木榄炭疽病病原菌菌株MLYB1A5在PDA培养基上菌落为圆形,气生菌丝绒毛状,中间灰色,边缘白色,菌落背面为灰白色,子囊壳棕色,分生孢子梗透明,光滑,有隔膜,分支,12~15 d开始产孢,分生孢子单细胞,椭圆形,两端钝圆或一端钝圆一端稍尖。分生孢子平均大小为(16.48±2.13)×(4.82±1.03)μm,(n=100)。根据形态特征和多基因系统发育分析将分离菌株鉴定为果生刺盘胞(Colletotrichum fructicola)。人工接种分离菌株,可以引起木榄叶片发病,症状与林间一致。从发病部位同样可以分离获得接种菌株。果生刺盘孢菌株MLYB1A5最适生长温度为28℃,最适pH值范围为4~9,最适产孢温度为30℃,平均产孢量为(23.54±0.53)×10^(6)个·mL^(-1),温度高于30℃时,产孢量急剧下降。果生刺盘孢菌株MLYB1A5最适碳源为蔗糖和可溶性淀粉,最适氮源为酵母粉和牛肉膏,最适培养基为PDA培养基。最适产孢碳源为果糖和麦芽糖。解淀粉芽孢杆菌(Bacillus amyloliquefaciens)对果生刺盘孢菌株MLYB1A5的菌丝生长抑制率达到(74.69±3.14)%。[结论]首次明确了果生刺盘胞是引起广东省湛江市木榄炭疽病的致病菌。该菌最适生长温度为28℃,对pH适应范围较广。首次发现解淀粉芽孢杆菌对果生刺盘孢菌株MLYB1A5的拮抗效果较好。[Objective]To identify the pathogen causing leaf anthracnose on Bruguiera gymnorhiza(largeleafed mangrove)in Zhanjiang City,Guangdong Province,characterize its biological features,and screen for antagonistic bacteria to effectively control the disease.[Methods]Surface sterilized infected leaf tissues were used for pathogen isolation and purification.The isolated strains were identified using both morphological and phylogenetic analysis based on concatenated ITS-TUB2-ACT-GAPDH.The pathogenicity of the isolated strain was confirmed by artificial inoculation of the isolated strain onto healthy B.gymnorhiza leaves.The basic biological characteristics of the fungus were studied,and antagonistic bacteria were screened using a co-culture method.[Results]The fungal strain MLYB1A5 formed round colonies with a gray center and white edges on the upper surface,and a grayish-white underside.The conidia were single-celled,cylindrical,with smooth hyaline walls,and had obtuse to slightly rounded ends.The average conidial size was(16.48±2.13)×(4.82±1.03)μm(n=100).Morphological characteristics and phylogenetic analysis identified the strain as C.fructicola.Artificial inoculation of the strain on B.gymnorhiza leaves caused symptoms consistent with those observed in the field.The pathogen was reisolated from the infected leaves,fulfilling Koch’s postulates.The optimal growth conditions for C.fructicola strain MLYB1A5 were at 28℃,with a pH range of 4 to 9.Sporulation was highest at 30℃,with an average spore count of(23.54±0.53)×10^(6)spores·mL^(−1),which sharply decreased above this temperature.Sucrose and soluble starch were the optimal carbon sources,while yeast extract and beef extract were the best nitrogen sources.The PDA medium significantly influenced the cultural and morphological traits of the fungus,and fructose and maltose were most favorable for sporulation.In bioassays,B.amyloliquefaciens inhibited the mycelial growth of C.fructicola by 75.25±2.79%.[Conclusion]C.fructicola is identified as the causal path

关 键 词：木榄炭疽病 病原菌鉴定 多基因系统分析 生物学特性 拮抗菌 

分 类 号：S436.65[农业科学—农业昆虫与害虫防治]