中国铁皮石斛茎腐病的病原鉴定

Pathogen identification of stem rot disease in Dendrobium officinale of China

为了研究铁皮石斛茎腐病的发生与防治,2013年4月至2015年8月,观察了铁皮石斛茎腐病症状、并进行了病原菌分离、致病性试验和病原菌鉴定。结果表明,该病害仅为害铁皮石斛茎秆,严重发生时,可导致病斑以上的茎秆死亡;TP-1菌株分离得率可达65.7%;接种病原菌14 d检查全部发病,出现水渍状坏死病斑,直径约3mm,症状与自然发病相似,再分离得到了原菌株。经形态学和DNA分子测序鉴定,确定TP-1为可可球二孢,它是引起铁皮石斛茎腐病的主要病原菌。这由可可球二孢造成铁皮石斛的茎腐病,属国内外首次报道。

For the control of stem rot disease in Dendrobium afficinale,the symptoms were observed,pathogen was isolated and identified in April 2013 to August 2015. The pathogen only infected the stem of D. officinale,resulting in the stem death above diseased spot. Strain TP-1 accounted for 65. 7% of the isolated fungi colonies. After inoculation of TP-1for 14 d,watery lesions about 3 mm in diameter occurred,which was similar to natural infections,and original strain was re-isolated. Morphological and sequencing identified that TP-1 is Lasiodiplodia theobromae,This is the first report of stem rot disease in D. afficinale caused by L. theobromae in China.