云南西双版纳地区橡胶树炭疽病菌的系统进化分析和室内药剂筛选

Phylogenetic Analysis and Fungicide Screening for Colletotrichum Causing Rubber Anthracnose in Xishuangbanna,Yunnan

【目的】旨在明确我国云南省主要植胶区——西双版纳橡胶树炭疽病菌复合群的种属分类,筛选橡胶树炭疽病菌Colletotrichum cliviae的防治药剂。【方法】采集分离西双版纳地区橡胶树炭疽病菌,通过形态学和多基因系统进化分析相结合的方法进行鉴定,并采用菌丝生长速率法对杀菌剂进行室内毒力测定。【结果】成功分离鉴定出35株橡胶树炭疽病菌,其中63%的菌株属于胶孢炭疽菌复合群,34%的菌株属于尖孢炭疽菌复合群。系统发育树进一步将35株炭疽菌归为4个种属,分别为胶孢炭疽菌复合群下的C.siamense,尖孢炭疽菌复合群下的C.laticiphilum和C.wanningense,以及云南首次发现的C.cliviae。另外,室内药剂筛选结果表明,咪鲜胺、苯醚甲环唑、嘧菌酯、吡唑醚菌酯、吡噻菌胺5种杀菌剂对云南和海南地区橡胶树C.cliviae菌株的EC_(50)值为0.075~1.09 mg/L,其中咪鲜胺抑制活性最佳。【结论】云南西双版纳地区橡胶树炭疽病菌的优势种为胶孢炭疽菌复合群下的C.siamense。咪鲜胺对我国新发现的橡胶树C.cliviae的抑制效果依然良好。本研究进一步提高了对橡胶树炭疽病菌分类的认识,为有效防治该病害提供了技术支持。

【Objective】The study aimed to identify Colletotrichum species complexes causing rubber anthracnose in Xishuangbanna,the main planting area of Yunnan province,China,and screen fungicides against Colletotrichum cliviae from rubber trees.【Method】The Colletotrichum isolates causing rubber anthracnose in Xishuangbanna were collected and identified by the morphological and multilocus phylogenetic analysis.The indoor toxicity of fungicides against C.cliviae was determined by the mycelium growth rate method.【Result】The 35 isolates obtained from rubber trees in Xishuangbanna were identified to Colletotrichum spp.The 63%of the 35 Colletotrichum isolates were identified as C.gloeosporioides species complex and the 34%as C.acutatum species complex.The phylogenetic tree classified the isolates into four species,C.siamense in the C.gloeosporioides species complex,C.laticiphilum and C.wanningense in the C.acutatum species complex,and the first-discovered species C.cliviaein Yunnan.In addition,the results of in vitro inhibitory activity against C.cliviae isolates from Yunnan province and Hainan province showed that the EC_(50) values of prochloraz,difenoconazole,azoxystrobin,pyraclostrobin and penthiopyrad was 0.075 to 1.09 mg/L,and prochloraz exhibited the best activity.【Conclusion】C.siamense,a known species of C.gloeosporioides species complex is the major causative agent of rubber anthracnose in Xishuangbanna,Yunnan.Prochloraz shows good inhibitory effects against the first-discovered species C.cliviae from rubber tree in China.This study improves the understanding of the classification of Colletotrichum species from rubber trees and provides technical support for effectively controlling rubber anthracnose.