进境美国加州脐橙中丁香疫霉phytophthora syringae 的截获.pdfVIP

菌物学报 jwxt@ 15 January 2012, 31(1): 24-30 Http:// Mycosystema ISSN1672-6472 CN11-5180Q © 2012 IMCAS, all rights reserved. 进境美国加州脐橙中丁香疫霉 Phytophthora syringae 的 截获 * 罗加凤 刘跃庭 廖芳 胡晓红 刘鹏 黄国明 天津出入境检验检疫局 天津 300461 摘 要：从产自美国加利福尼亚州的新鲜脐橙样品中发现多个腐烂病果，通过分离培养得到 3 个疑似丁香疫霉 Phytophthora syringae 菌株，对 3 个菌株进行形态学研究、致病性测定和分子序列比对分析。结果表明病菌在 V8A 培养基上菌落稀疏、平铺，呈星状，菌丝紧贴培养基生长或埋于基质内生长；在 PDA 培养基上菌落呈菊花花瓣状， 菌丝致密，乳白色；游动孢子囊和菌丝膨大体在无菌水和土壤浸出液中黑暗条件下 48h 后产生；菌株为同宗配合， 卵孢子在带有新鲜脐橙果实组织或杜鹃叶片的 V8A 培养基中大量产生；创伤接种脐橙果实，7d 后接种脐橙出现典型 的褐腐症状；通用引物 ITS1/ITS4 扩增测序，Blastn 分析表明序列与 GenBank 中P . syringae 序列相似性为 99% 。依 据上述研究结果，将分离获得的 3 株菌鉴定为丁香疫霉 Phytophthora syringae ，系国内首次截获的一种植物检疫性真 菌病害。 关键词：柑橘，丁香疫霉，形态学特征，致病性测定，序列比对 Interception of Phytophthora syringae on Citrus fruits imported from California, USA * LUO Jia-Feng LIU Yue-Ting LIAO Fang HU Xiao-Hong LIU Peng HUANG Guo-Ming Tianjin Entry-Exit Inspection and Quarantine Bureau, Tianjin 300461, China Abstract: Several brown rot fruits have been found from Californian fresh orange sample. Three isolates similar to Phytophthora syringae were obtained from these rot fruits. The colonies grew slowly on PDA and V8 juice agar (V8A). They were stellate, tiled and thin on V8A, but on PDA, the margin was chrysanthemum petaloid; mycelia dense, milk-white-colored. Sporangia and catenulate hyphal swellings formed in sterilizing water and soil extract water in 48h. The isolates were homothallic. Oospores were produced abundantly on PDA and V8A mixed with fresh Citrus fruit tissue or leaf of rhododendron. The isolates were wounded-inoculated on fres