云南玉溪冰糖橙果斑病致病菌的鉴定及室内药剂筛选

Identification of fruit spot pathogen on the fruit of Bingtang oranges in Yuxi area of Yunnan province and laboratory screening of fungicides

2017年,采集云南玉溪冰糖橙典型果斑病病果,从病灶组织中分离致病菌,根据形态学特征、致病性和多种保守基因序列分析对病原菌进行鉴定,并进行室内药剂筛选。分离获得的3个菌株guo-1、NS2-2、NS2-6经鉴定为茎点霉(Phoma sp.),对当年生冰糖橙叶片和果实的致病力较强;基于ITS、SSU、EF1-α、LSU、TUB、ACT的系统发育分析表明,致病菌与Phoma sp.处于同一个分支。室内药剂筛选结果表明,3%噻霉酮可湿性粉剂、11.5%吡唑嘧菌酯悬乳剂、22.5%咪鲜胺水乳剂和60%唑醚代森联水分散粒剂对玉溪冰糖橙果斑病致病菌有明显的抑制效果。

Bingtang oranges with fruit spot were collected in Yuxi area of Yunnan province in 2017,the pathogens were isolated from typical lesions of Bingtang oranges.According to the morphological characteristics,pathogenicity and a variety of conservative gene sequence analysis,the pathogens were identified and the drugs against the pathogens were screened in the laboratory.The results showed that the isolated three strains guo-1,NS2-2 and NS2-6 belong to Phoma sp.,which had strong pathogenicity to the leaves and fruits of the current year’s Bingtang orange;the phylogenetic analysis based on ITS,SSU,EF1-α,LSU,TUB and ACT showed that the pathogenic bacteria were in the same branch with Phoma sp.;the inhibition effect of 3%thiamycin wettable powder,11.5%pyrazoxystrobin suspension,22.5%prochloraz water emulsion and 60%dimefon water dispersible granule on the pathogen was obvious.