橡胶树叶斑病病原菌鉴定及其生物学特性测定和防治药剂筛选  

Identification and biological characterization of rubber tree leaf spot disease pathogen and fungicide screening

作　　者：施玉萍[1] 刘一贤[1] 李岚岚 戴利铭 蔡志英[1] SHI Yu-ping;LIU Yi-xian;LI Lan-lan;DAI Li-ming;CAI Zhi-ying(Yunnan Institute of Tropical Crops,Jinghong,Yunnan 666100,China)

机构地区：[1]云南省热带作物科学研究所,云南景洪666100

出　　处：《南方农业学报》2022年第9期2575-2584,共10页Journal of Southern Agriculture

基　　金：西双版纳橡胶林生态系统云南省野外科学观测研究站项目(202205AM070004);云南省“三区”人才支持计划项目(599-18);云南省财政专项(RF2022-7)。

摘　　要：【目的】明确一种橡胶树新叶斑病的病原菌分类地位及其生物学性状,筛选有效的防治药剂,为其防治提供理论依据。【方法】以采自云南省普洱市江城县曲水镇怒那村橡胶树苗圃的橡胶叶斑病病叶为材料,采用组织分离法和单胞分离法进行病原菌分离纯化,结合柯赫氏法则进行致病性测定,通过形态特征观察及ITS、GADPH、TEF1-α多基因序列分析对病原菌进行分类鉴定;采用单因子变量法研究病原菌生物学特性;采用菌丝生长速率法测定8种药剂对该叶斑病病原菌的毒力。【结果】经组织分离法从橡胶病叶上分离获得2株真菌分离物,其中菌株JCMP17a的孢子形态与感病叶片上挑取的孢子形态相似。柯赫氏法则证明菌株JCMP17a是橡胶树叶斑病的致病菌,该菌的形态特征与双色平脐蠕孢(Bipolaris bicolor)相似,且多基因联合聚类分析显示与B. bicolor聚在系统发育进化树同一分支上。菌株JCMP17a最适生长温度为28℃,最适生长p H 7;致死温度为55℃处理15 min;能利用多种碳源和氮源,碳源以可溶性淀粉最有利于菌丝生长,牛肉浸膏为最适氮源;全黑暗(0 L∶24 D)和光暗交替(12 L∶12 D)条件下均有利于菌丝生长。250 g/L苯醚甲环唑、30%咪鲜胺和250 g/L戊唑醇对病原菌有很好的抑制效果,EC_(50)分别为0.1158、0.2427和0.2613 mg/L。【结论】引起云南省普洱市江城曲水镇怒那村橡胶树苗圃橡胶叶斑病的病原菌为双色平脐蠕孢,这是首次在云南植胶区内发现双色平脐蠕孢侵染引起橡胶叶斑病。250 g/L苯醚甲环唑乳油、30%咪鲜胺微囊悬浮剂和250 g/L戊唑醇水乳剂可用于该病害的防治。【Objective】To identify taxonomic status and biological characteristics of a rubber tree leaf spot disease pathogen,and to screen fungicides,so as to provide theoretical basis for the control and prevention.【Method】Rubber leaves infected with leaf spot collected from seedling nursery in Nuna Village,Qushui County,Puer City,Yunnan Province were taken as materials. Pathogens was isolated and purified by tissue isolation and single-spore isolation method,and their pathogenicity were determined by Koch’s postulates test. Based on morphological characteristics and ITS,GADPH,TEF1-α multigene sequence analyses,the pathogen was classified and identified. Biological characteristics were determined with single factor variable experiment. Toxicities of 8 kinds of fungicides were tested through mycelial growth rate method.【Result】Two fungal isolates were obtained from the diseased rubber leaves through tissue isolating method,in which the spore morphology of JCMP17a was similar to that of the spores from diseased leaves. Isolate JCMP17a from the infected tissues was determined to be the pathogen of the disease through Koch’s postulates. Morphological characteristics of the fungi were consistent with those of Bipolaris bicolor. According to multigene cluster analysis showed that the pathogen was clustered in the same evolutionary branch of phylogenetic tree with B. bicolor. For strain JCMP17a optimum mycelial growth temperature was 28 ℃ with p H of 7,and the lethal temperature for was 55 ℃ for 15 min. Diverse carbon resources could be used. The best carbon source was soluble starch,and the best nitrogen source was beef extract. Full darkness(0 L∶24 D),light and darkness alternation(12 L∶12 D)were good for mycelial growth. The best fungicides against the mycelial growth of the pathogen were 250 g/L of difenoconazole,30% of prochloraz and 250 g/L of tebuconazole with the EC_(50) value of 0.1158,0.2427 and 0.2613 mg/L.【Conclusion】Leaf spot disease pathogen from the germplasm nursery in seedling nurser

关 键 词：橡胶树 叶斑病 双色平脐蠕孢 鉴定 生物学性状 药剂筛选 

分 类 号：S435.76[农业科学—农业昆虫与害虫防治]