摘要
根腐病近年在地黄主产区普遍发生,对地黄产量及品质影响很大。该研究从地黄主产区采集的地黄根腐病样中分离到1株不同于以往报道的新病原,其在PDA培养基上菌落呈灰黑色,菌丝结构致密,气生菌丝欠发达,菌落背面呈黑色。该病菌菌丝粗细不均,直径2~3μm,多有相互缠绕;病菌产孢结构未见,分生孢子小型,近圆形,直径约1μm。将病菌离体接种健康地黄块根,保湿培养数天后接种部位黑褐色腐烂;活体接种健康地黄根部土壤,正常培养数天后地黄苗叶片失水萎蔫,根部黑褐色腐烂,与田间症状一致。病菌基因组DNA经真菌rDNA-ITS通用引物ITS1/ITS4扩增及同源性分析,供试菌株与Heterophoma sp.,Phoma sp.,P.novae-verbascicola及P.herbarum聚为一支,核酸序列同源性为99.21%~99.43%;经tub2基因专用引物Btub2Fd/Btub4Rd扩增及同源性分析,供试菌株与H.verbascicola,H.novae-verbascicola,H.poolensis,P.herbarum,H.sylvatica,H.verbascicola,H.verbasci-densiflori核酸序列同源性为97.00%~98.02%,与H.novae-verbascicola亲缘关系最近;经lsu基因专用引物LR0R/LR7扩增及同源性分析,供试菌株与H.novae-verbascicola聚为一支。结合形态特征观察、核酸序列比对及科赫氏法则验证结果,最终将该病菌鉴定为H.novae-verbascicola。该研究工作对后续开展地黄根腐病理论研究及根腐病田间防治具有重要意义。
Root rot was occurred widely in the production area of Rehmannia glutinosa, and which result in serious influence on the yield and quality of R. glutinosa. In the present work, a new phytopathogen was isolated from roots with root rot symptom in the production area of R. glutinosa. The colony of the pathogen growing on PDA medium was gray-black, the structure of hyphae was compact, the aerial hyphae was less developed, and the back of the colony was black. The hyphae of the pathogen were uneven in size, about 2 to 3 μm in diameter and twined with each other, the conidia of the pathogen were small, nearly round and about 1 μm in diameter. The healthy roots of R. glutinosa were inoculated with the pathogen in vitro, black-brown rot was observed at the inoculate sites after a few days′ incubation. The rhizosphere soil of healthy R. glutinosa seedlings were inoculated in vivo, the leaves were wilted and the roots were black-brown rotted after several days′ normal culture, the symptoms were consistent with those observed in the field. The genomic DNA of the pathogen was amplified by fungus rDNA-ITS universal primer ITS1/ITS4 and homologous analyzed, the pathogen was in a branch with Heterophoma sp., Phoma sp., P. novae-verbascicola and P. herbarum with the nuclear acid homology of 99.21% to 99.43%. The pathogen shown 97.00% to 98.02% nuclear acid homology with H. verbascicola, H. novae-verbascicola, H. poolensis, P. herbarum, H. sylvatica, H. verbascicola and H. verbasci-densiflori when amplified by the tub2 gene special primer Btub2 fd/Btub4 rd, and H. novae-verbascicola was the highest. The pathogen was in a branch with H. novae-verbascicola when amplified by the lsu gene special primer LR0 R/LR7. Based on the morphological characteristics, nucleotide sequence analysis and Koch′s test results, the isolated pathogen causing root rot of R. glutinosa was identified as H. novae-verbascicola. This study is of great significance for the further theoretical research on root rot of R. glutinosa and root rot control in field.
作者
李勇
王蓉
陈卉青
魏若凡
刘琨
丁万隆
LI Yong;WANG Rong;CHEN Hui-qing;WEI Ruo-fan;LIU Kun;DING Wan-long(Institute of Medicinal Plant Development,Chinese Academy of Medical Sciences&Peking Union Medical College,Beijing 100193,China)
出处
《中国中药杂志》
CAS
CSCD
北大核心
2021年第11期2783-2787,共5页
China Journal of Chinese Materia Medica
基金
中国医学科学院医学与健康科技创新工程项目(2016-I2M-3-017)。
关键词
地黄
根腐病
病原菌
分子鉴定
Rehmannia glutinosa
root rot
phytopathogen
molecular identification
