金莲花苗期猝倒病病原菌的分离鉴定  

Isolation and identification of pathogen causing damping off at seedling stage of Trollius chinensis

作　　者：李勇[1] 王蓉[1] 魏若凡 丁万隆[1] LI Yong;WANG Rong;WEI Ruo-fan;DING Wan-long(Institute of Medicinal Plant Development,Chinese Academy of Medical Sciences&Peking Union Medical College,Beijing 100193,China)

机构地区：[1]中国医学科学院北京协和医学院药用植物研究所,北京100193

出　　处：《中国中药杂志》2021年第12期3102-3105,共4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);河北省重点研发计划项目(20326301D)。

摘　　要：金莲花是我国传统中药材,目前野生资源已濒临枯竭,市售药用金莲花主要依赖人工栽培。猝倒病是金莲花苗期主要病害之一,对金莲花种苗繁育威胁较大。迄今,未见金莲花猝倒病相关报道。为此,笔者2018年从河北沽源金莲花种苗繁育基地采集相关病害样本,开展病菌分类学鉴定研究。金莲花猝倒病每年5月中旬至6月下旬在产区发生,病害初期,金莲花茎基部出现褐色斑点,后病斑环周扩展缢缩,最终植株倒伏死亡。病菌分离物在PDA培养基上生长迅速,灰白色气生菌丝发达,后期菌丝逐渐变为棕褐色,在菌落中部及外围生成大量暗褐色小菌核,菌丝直径710μm,近直角或锐角分枝,近分枝处有隔膜,分枝及隔膜处多有缢缩。病菌分离物接种健康金莲花幼苗后很快发病,且与田间发病症状一致。经rDNA-ITS序列比对,该病菌与立枯丝核菌Rhizoctonia solani及其AG-1 IC菌丝融合群、丝核菌有性型瓜亡革菌Thanatephorus cucumeris同源性高达99.49%99.84%,且病菌分离物与立枯丝核菌R.solani AG-1 IC菌株有明显的菌丝融合现象。基于上述研究结果,将该病菌分离物鉴定为立枯丝核菌R.solani AG-1 IC菌丝融合群。研究结果对后续开展病菌相关基础生物学研究以及病害综合防控具有重要参考价值。Trollius chinensis is a traditional Chinese medicinal material in China, the wild resource of T. chinensis are now exhausted, and commercial medicinal T. chinensis mainly depends on artificial cultivation. As one of the most severely happened diseases at the seedling period, damping off has been a serious threaten to the breeding of T. chinensis seedlings. However, no related research have been reported so far. So, the authors collected damping-off samples of T. chinensis in 2018 from seedling breeding nursery in Guyuan, Hebei province, and carried out study on taxonomic identification of the pathogen. Damping off occurs in the T. chinensis production area from mid-May to late June every year. At the beginning, brown lesions were observed on the basal stem, then the lesions circumferential expanded and constricted, and finally resulted in the fall and death of T. chinensis seedlings. Pathogenic isolate was growing rapidly on the PDA medium, well developed aerial mycelia were grey white at first, then turned brown gradually, and a great number of small dark brown sclerotia were developed in the middle and periphery of the colony. Mycelial diameter of the pathogen was about 7 to 10 μm, near right angle or acute angle branches, near branches with septa, branches and septa with constriction. After the healthy T. chinensis seedlings were inoculated by pathogenic isolate, damping-off was observed soon, and the symptom was as same as those observed in the field. Through homogenous blast, the rDNA-ITS sequence of the pathogenic isolate shown 99.49% to 99.84% homology with Rhizoctonia solani, R. solani AG-1 IC mycelium anastomosis group and Thanatephorus cucumeris, the sexual type of Rhizoctonia. Furthermore, obvious mycelial anastomosis phenomena were observed when the pathogenic isolate and R. solani AG-1 IC strain were confronting cultured. Based on the results above, the pathogenic isolate causing damping off of T. chinensis was identified as R. solani AG-1 IC mycelial anastomosis group. Results in the present work h

关 键 词：金莲花 猝倒病 立枯丝核菌 病原鉴定 

分 类 号：S435.672[农业科学—农业昆虫与害虫防治]