洛阳市牡丹灰霉病病原菌的鉴定
Identification of gray mold pathogens on tree peony Paeonia suffruticosa in Luoyang

为明确洛阳市牡丹灰霉病的病原菌种类，于2015年从该地区的4个牡丹Paeonia suffruticosaAndr.种植区采集灰霉病样品，采用组织分离法对病原菌进行分离和纯化，结合形态学和基因序列分析对分离物进行鉴定，采用针刺接种法测定不同分离物对牡丹离体叶片的致病性。结果表明，从灰霉病样品中分离获得40株分离物，这些分离物分别属于I、Ⅱ、Ⅲ型菌，I型菌不易产孢但产菌核；Ⅱ型菌易产孢，后期产生少量菌核；Ⅲ型菌易产孢，且产生大量菌核。产孢分离物均形成直立状分生孢子梗，孢子梗分枝顶端聚生葡萄穗状分生孢子，分生孢子卵圆形或长卵圆形。供试菌株的ITS序列和G3PDH基因序列与灰葡萄孢Botrytis cinerea Pers.的同源性达到99%；致病性测定结果表明，各菌群代表菌株对牡丹均有致病性，但不同菌群间致病力有差异。研究表明，引起洛阳市牡丹灰霉病的病原菌为灰葡萄孢，且菌群类型多样。
In order to clarify the pathogen causing tree peony gray mold, the infected leaves were collected from four tree peony-growing regions in Luoyang in 2015. The pathogenic isolates were obtained by tissue isolation methods and were identified based on morphological characteristics and gene sequencing analysis. The pathogenicity of isolates was carried out in vitro by leaf acupuncture inoculation. The results showed that forty isolates were obtained from infected leaves and they were divided into three groups:group I with sclerotia but without conidia; group Ⅱ with conidia and a little sclerotia; group Ⅲ with conidia and a large number of sclerotia. The conidiophores of spore isolates were erect and the terminal branch expanded with a large number of conidia like grape spikes, the conidia were ovoid or elliptical in shape. The ITS regions and G3PDH gene sequences of the representative isolates were 99% similar to Botrytis cinerea Pers.. The results of tree peony leaves pathogenicity test showed that all the representative isolates could infect the leaves, but their pathogenicity were different and the pathogenic fungus of tree peony gray mold was B. cinerea in Luoyang, and the pathogenic isolate type was complex.