福建省多花黄精根腐病的病原菌鉴定

Identification of Root Rot Pathogens on Polygonatum cyrtonema in Fujian

【目的】明确福建地区多花黄精根腐病的发病率和病原菌种类,并为该病害的防治提供理论依据。【方法】调查福建省3个多花黄精种植基地的根腐病发病率,并采集具有典型根腐病症状的植株和块根病样,分离纯化获得病原菌,利用形态学特征、分子生物学特征及致病性测定对其进行鉴定。【结果】福建省多花黄精种苗的根腐病平均发病率为10.50%,采收时根茎的根腐病平均发病率为17.65%。分离纯化获得98株菌株,结合菌株的形态学特征、特异性引物FOF1/FOR1和F8/R8、tef-1α基因序列分析,分别鉴定为尖孢镰刀菌Fusarium oxysporum、腐皮镰刀菌F.solani和藤仓镰刀菌F.fujikuroi,三者的分离频率依次为75.51%、20.41%和4.08%。代表性菌株经回接根茎进行致病性检测发现其发病症状与田间表现一致,符合柯赫氏法则。【结论】尖孢镰刀菌、腐皮镰刀菌和藤仓镰刀菌是福建地区多花黄精根腐病的主要病原菌,首次报道藤仓镰刀菌可引起我国多花黄精根腐病。

【Objective】Pathogens that caused the root rot disease on Polygonatum cyrtonema Hua in Fujian were identified.【Methods】Based on the survey of P.cyrtonema root rot disease in three planting areas in the province,infected plants and rhizomes were sampled to isolate the microbes.Suspected pathogens were examined morphologically and molecular biologically prior to a pathogenicity test for a confirmed identification.【Results】Approximately 10.50% the typical disease symptoms appeared on the seedlings,and 17.65% on the rhizomes at harvest.Based on the morphological characteristics,FOF1/FOR1 and F8/R8 PCR amplification of specific primers,and sequences of translation elongation factor-1α(tef-1α) gene,the pathogens that caused the infection were identified to include Fusarium oxysporum,F.solani,> and F.fujikuroi from 98isolates.The frequency of isolating F.oxysporum from the collected samples was 75.51%,20.41% on F.solani,and 4.08% on F.fujikuroi.Inoculating the isolated pathogens on healthy rhizomes reproduced the same symptoms as observed in the field and followed Koch's rules.【Conclusion】F.oxysporum,F.solani,and F.fujikuroi were identified to be the pathogens of the root rot disease on P.cyrtonema in Fujian.F.fujikuroi was the first time to be associated with the outbreak in China.