杨树灰斑病菌(Coryneum populinum Bres.)对5种杀菌剂的敏感性  

Sensitivity of Coryneum populinum Bres.to Five Fungicides

作　　者：唐秀丽 杨建敏 孟志龙 石瑛[1,2] TANG Xiu-li;YANG Jian-min;MENG Zhi-long;SHI Ying(College of Biological Sciences and Technology,Taiyuan Normal University,Jinzhong 030619,China;Shanxi Vocational University of Engineering Science and Technology,Jinzhong 030619,China)

机构地区：[1]太原师范学院生物科学与技术学院,山西晋中030619 [2]山西工程科技职业大学,山西晋中030619

出　　处：《林业科学研究》2023年第5期160-168,共9页Forest Research

基　　金：山西省重点研发项目(201603D221008-1);山西省教育厅高校科技创新项目(2020L0523);太原师范学院研究生创新项目(SYYJSYC-2246)。

摘　　要：[目的]在测定杨树灰斑病菌最适生长温度的基础上,开展病菌对5种杀菌剂的敏感性试验,为进一步筛选出可用于杨树灰斑病防治的有效药剂和明确杀菌剂对病菌的作用机制提供理论参考。[方法]采用菌丝生长速率法和分生孢子萌发法测定5种供试杀菌剂对C.populinum菌丝生长和分生孢子萌发的抑菌效果,构建毒力回归方程并计算EC50值;同时,利用光学显微镜观察杀菌剂对菌丝生长和分生孢子萌发的影响。[结果]C.populinum的最适生长温度为20℃,20℃条件下,第25 d菌落直径为4.25 cm,12 h分生孢子萌发率为79.00%;30℃条件下,病菌菌丝生长和分生孢子萌发均受到抑制。室内试验发现5种供试杀菌剂对C.populinum菌丝生长的抑制作用效果表现为恶醚唑>戊唑醇>多菌灵>咪鲜胺>甲基托布津,平均EC50值分别为0.0048、0.024、0.047、0.25和0.49μg·mL^(−1);对分生孢子萌发率的抑制作用效果表现为恶醚唑>咪鲜胺>甲基托布津>多菌灵>戊唑醇,平均EC50值分别为85.07、101.23、123.28、254.80和327.78μg·mL^(−1)。恶醚唑作用后病菌菌丝表面粗糙、分支处膨大,不产孢;分生孢子形态异常,出现芽管分支、膨大或不伸长等畸形特征。[结论]恶醚唑对杨树灰斑病菌具有较高的抑菌活性,是田间防治杨树灰斑病的有效候选药剂。[Objective]On the basis of the optimum mycelial growth temperature investigation of Coryneum populinum Bres,the pathogen was measured for susceptibility to five fungicides.The approach provides a theoretical reference for disease control of poplar gray spot and fungicide acting mechanism against the pathogen.[Method]The mycelium growth rate method and conidia germination method were used to determine the antibacterial effects of five tested fungicides on C.populinum mycelium growth and conidia germination,and the toxicity regression equation was constructed and the EC50 value was calculated.The morphological changes of mycelia and conidial germination were observed after fungicide treatment.[Result]The optimum mycelial growing temperature of C.populinum was 20℃with the colony diameter of 4.25cm after 25 days,and the conidial germination rate was 79.00%after 12h on PDA.The mycelial growth and conidial germination were both inhibited at above 30℃.The inhibitory effects of the five fungicides on mycelial growth of the pathogen showed the trend of Difenoconazole>Tebuconazole>Carbendazim>Prochloraz>Thiophanate-methyl,with the average EC50 values of 0.0048,0.024,0.047,0.25 and 0.49μg·mL^(−1),respectively.The virulence of the five fungicides to the pathogen’s conidial germination showed the pattern of Difenoconazole>Prochloraz>Thiophanate-methyl>Carbendazim>Tebuconazole,with the average EC50 values of 85.07,101.23,123.28,254.80 and 327.78μg·mL^(−1),respectively.The hyphal surface of the pathogen became rough with enlarged branches,and no spore was produced after application of Difenoconazole.The conidial germination became morphologically abnormal with branching and enlargement or no enlagement of germ tubes.[Conclusion]The fungicide difenoconazole has high virulence to C.populinum,and it shows a potentially effective candidate agent for management of popular grey spot.

关 键 词：杨棒盘孢菌 温度 药剂 EC50 显微形态 

分 类 号：S763.1[农业科学—森林保护学]