福建省彩叶草叶斑病病原菌的分离鉴定与室内药剂筛选  

Pathogen Identification and Fungicide Selection for Leaf Spot Disease on Plectranthus scutellarioides in Fujian

作　　者：王荣波[1] 陈姝樽 李本金[1] 刘裴清[1] 邓丽霞 翁启勇[1] WANG Rongbo;CHEN Shuzun;LI Benjin;LIU Peiqing;DENG Lixia;WENG Qiyong(Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests/Institute of Plant Protection,Fuzhou,Fujian 350013,China)

机构地区：[1]福建省农业科学院植物保护研究所/福建省作物有害生物监测与治理重点实验室,福建福州350013

出　　处：《福建农业学报》2021年第12期1471-1477,共7页Fujian Journal of Agricultural Sciences

基　　金：福建省科技计划公益类专项(2019R1024-4);福建省自然科学基金项目(2021J01478);福建省农业科学院科技创新团队建设项目(CXTD2021002-1);福建省农业高质量发展超越“5511”协同创新工程项目(XTCXGC2021017、XTCXGC2021011);福建省农业科学院对外合作项目(DWHZ2021-13)。

摘　　要：【目的】明确福建省彩叶草(Plectranthus scutellarioides)叶部病害的病原种类,筛选可用于病害防控的化学药剂。【方法】采用常规组织分离法获得病原菌株并进行柯赫氏法则验证,结合形态学与分子生物学(ITS与LSU序列)对分离菌株进行鉴定,采用生长速率法测定6种杀菌剂对该病原菌的室内毒力。【结果】用分离菌株ZZCYC1706分生孢子接种彩叶草,侵染叶片症状与田间症状相似;形态特征及ITS和LSU多基因序列分析表明,该病原菌为链格孢(Alternaria alternata)。供试6种药剂室内毒力测定结果显示,96%啶菌恶唑抑菌效果最好,其EC50为0.621μg·mL^(−1),其次为98%异菌脲和95%嘧霉胺,EC50分别为1.155、5.258μg·mL^(−1);而96.4%克菌丹效果较差,EC50值最高,为89.010μg·mL^(−1)。【结论】福建漳州彩叶草叶斑病病原菌鉴定为链格孢(A.alternata),该发现为国内首次报道。啶菌恶唑、异菌脲和嘧霉胺对该病原菌的毒力较高,并分属不同药剂类型,可用于链格孢引起叶斑病的防治。【Objective】Identification of the leaf spot pathogen on Plectranthus scutellarioides in Fujian and screening fungicides for effective disease prevention and control were conducted.【Method】A causative pathogen was isolated from the diseased tissues,and the species verified by Koch’s rule,morphological observations under a microscope,and molecular ITS and LSU sequence analyses.An in vitro toxicity test on 6 commercially available fungicides was performed on the pathogen to determine their efficacy.【Result】The coleus leaves inoculated with the conidia of the isolated ZZCYC1706 produced same symptoms as those observed on the diseased plants in the field.The ITS and LSU sequences of ZZCYC1706 suggested it be Alternaria alternata.The toxicity test showed,among the 6 fungicides,96%pyrisoxazole to be most effective in inhibiting the pathogenic growth with the lowest EC50 of 0.621μg·mL^(−1).It was followed by 98%iprodione with an EC50 at 1.155μg·mL^(−1),95%pyrimethanil at 5.258μg·mL^(−1),and 96.4%captan,which was the least effective,at 89.010μg·mL^(−1).【Conclusion】The pathogen of the leaf spot disease on P.scutellarioides in Fujian province was identified as A.alternata,which was the first reported in China.The fungicides,pyrisoxazole,iprodione,and pyrimethanil,were shown in the laboratory effective in inhibiting the growth of A.alternata.And,being of different types,these fungicides could potentially be applicable for the coleus leaf spot disease control with a reduced concern of the development of drug resistance by the pathogen.

关 键 词：彩叶草 叶斑病 链格孢 毒力测定 EC50 

分 类 号：S436[农业科学—农业昆虫与害虫防治]