唐山地区柴胡根腐病病原菌分离鉴定及生物学特性研究

Identification and Biological Characteristics of Root Rot Pathogen of Bupleurum chinense DC. in Tangshan Area

柴胡根腐病在河北唐山地区呈逐年加重趋势,严重影响了柴胡的产量和质量。为了明确唐山地区柴胡根腐病病原菌的种类,在对柴胡根腐病菌分离纯化的基础上,通过菌落形态观察与病原菌16s rDNA分析,鉴定病原菌种类,并分析了病原菌的生长特性。结果表明:通过对分生孢子等形态学观察,初步认为柴胡根腐病病原菌属镰刀菌属;应用rDNA ITS区的通用引物对病原菌基因组DNA进行PCR扩增,PCR产物测序后经BLAST分析,检测结果与形态学鉴定结果一致,确定病原菌是腐皮镰刀菌(Fusarium solan)i。菌丝体在PDA培养基中的最适生长温度为25℃,适宜生长pH值为6~8。致病菌孢子在30℃时萌发率最高;适宜萌发pH值为6~8;孢子在25℃水滴中2 h后开始萌发,9 h后萌发率达到100%;孢子临界致死条件为50℃、10 min。

Plate dilution method were used to identification of root rot pathogen of Bupleurum chinense DC.in Tangshan area,and pathogenicity was test through in vivo and in vitro experiments.The pathogen was preliminarily identified as Fusarium spp.according to its morphology,color and growth rate of the colonies,and morphology of macroconidia,microconidia,chlamydospores,and conidiophores.The fungal rDNA ITS was amplified and sequenced.The sequencing results was accepted by GenB ank and the accession number is KU747010.The results of molecular detection and morphologic observation both showed that the pathogens causing root rot of Bupleurum chinense DC.is Fusarium solani.Pathogens optimum grow temperature and pH value were 25℃ and 6-8,respectively.Under the environment of 25℃,the spore began to germinate in 2 hours and germination rate reached 100%after 9 hours.The killing conditions of spore were 50℃,10 min.