Grabke A, Hu M J, Luo C X, Bryson P K, Schnabel G
Fachbereich Biologie, Westfälische Wilhelms-Universität, 48149 Münster, Germany.
Department of Plant Pathology, College of Plant Sciences and Technology and the Key Lab of Crop Disease Monitoring and Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan, PR China.
Plant Dis. 2011 Jun;95(6):772. doi: 10.1094/PDIS-02-11-0113.
Monilinia fructicola (G. Wint.) Honey is a causal agent of brown rot of stone fruits but may also affect pome fruits. M. fructicola is common in North America, Oceania, and South America as well as in Asia, but it is listed as a quarantine pathogen in Europe (3). Since its first discovery in Europe in 2001 (France), it has been reported in Spain, Slovenia, Italy, and Switzerland. Recently, the fungus was also detected in orchards of blackberries and plums in the State of Baden-Württemberg, Germany (4). In July 2010, apples (Malus domestica Borkh.) of the cultivar Jonagold were found in a residential backyard in Fronhausen an der Lahn located in the State of Hessen, Germany with symptoms resembling brown rot caused by Monilinia species. Affected apples were at or near maturity with brown decay that had spread throughout the fruits. On the surface of the decaying apples was tan to white zones of sporulation. Upon isolation, the mycelium grew at a linear rate of 9.2 mm per day at 22°C on potato dextrose agar forming branched, monilioid chains of grayish colonies with concentric rings and little sporulation. The lemon-shaped spores had an average size of 14 × 9 μm, a shape and size consistent with M. fructicola. The ribosomal ITS1-5.8S-ITS2 region was PCR-amplified from genomic DNA obtained from mycelium using primers ITS1 and ITS4. A BLAST search in GenBank revealed highest similarity (99%) to M. fructicola sequences from isolates collected in China, Italy, and Slovenia (GenBank Accession Nos. FJ515894.1, FJ411109.1, GU967379.1). The M. fructicola sequence from the apple isolate was submitted to GenBank (Accession No. JF325841). The pathogen was also identified to the species level and confirmed to be M. fructicola using two novel PCR techniques based on cytochrome b sequences (1,2). Pathogenicity was confirmed by inoculating three surface-sterilized, mature apples cv. Gala with a conidial suspension (10 spores/ml) of the apple isolate. Fruit were stab inoculated at three equidistant points to a depth of 10 mm using a sterile needle. A 30-μl droplet was placed on each wound; control fruit received sterile water without conidia. After 5 days of incubation at room temperature in air-tight plastic bags, the inoculated fruits developed typical brown rot symptoms with sporulating areas (as described above). The developing spores on inoculated fruit were confirmed to be M. fructicola. All control fruits remained healthy. To our knowledge, this is the first report of M. fructicola on apple in Germany and more indication of further geographical spread of the quarantine disease in Germany. References: (1) J.-M. Hily et al. Pest Manag. Sci. Online publication. doi 10.1002/ps.2074, 2011. (2) S. Miessner and G. Stammler. J. Plant Dis. Prot. 117:162, 2010. (3) OEPP/EPPO. EPPO A2 list of pests recommended for regulation as quarantine pests. Version 2009-09. Retrieved from http://www.eppo.org/QUARANTINE/listA2.htm , September 22, 2010. (4) OEPP/EPPO. Reporting Service. No. 1, January 2010. Retrieved from http://archives.eppo.org/EPPOReporting/2010/Rse-1001.pdf , September 22, 2010.
桃褐腐病菌（Monilinia fructicola (G. Wint.) Honey）是核果褐腐病的病原，也可侵染仁果类果实。该病菌在北美、大洋洲、南美洲以及亚洲均有分布，但在欧洲被列为检疫性有害生物（3）。自2001年在欧洲首次发现（法国）以来，西班牙、斯洛文尼亚、意大利和瑞士均有报道。最近，在德国巴登-符腾堡州的黑莓和李子果园中也检测到了该病菌（4）。2010年7月，在德国黑森州拉恩河畔弗罗恩豪森的一个居民后院发现了乔纳金品种的苹果（Malus domestica Borkh.）出现类似由链核盘菌属（Monilinia）引起的褐腐病症状。受侵染的苹果已接近成熟或处于成熟阶段，果实出现褐色腐烂，并蔓延至整个果实。在腐烂苹果表面有黄褐色至白色的产孢区域。分离培养后，该病原菌在22°C的马铃薯葡萄糖琼脂培养基上以每天9.2毫米的线性速度生长，形成分支状、念珠状的灰色菌落链，有同心环，产孢较少。柠檬形孢子平均大小为14×9微米，其形状和大小与桃褐腐病菌一致。使用引物ITS1和ITS4从菌丝体基因组DNA中PCR扩增核糖体ITS1-5.8S-ITS2区域。在GenBank中进行BLAST搜索发现，与从中国、意大利和斯洛文尼亚收集的桃褐腐病菌分离株序列相似度最高（99%）（GenBank登录号：FJ515894.1、FJ411109.1、GU967379.1）。苹果分离株的桃褐腐病菌序列已提交至GenBank（登录号：JF325841）。利用基于细胞色素b序列的两种新型PCR技术，该病原菌也被鉴定到种水平，并确认是桃褐腐病菌（1,2）。通过用苹果分离株的分生孢子悬浮液（10个孢子/毫升）接种三个表面消毒的成熟嘎拉苹果来确认致病性。使用无菌针头在果实上三个等距点刺接种至10毫米深度。在每个伤口上放置30微升的液滴；对照果实接种无菌水而无分生孢子。在室温下于密封塑料袋中培养5天后，接种的果实出现典型的褐腐病症状并带有产孢区域（如上所述）。接种果实上发育的孢子经确认是桃褐腐病菌。所有对照果实均保持健康。据我们所知，这是德国关于桃褐腐病菌侵染苹果的首次报道，也进一步表明了这种检疫性病害在德国有进一步的地理扩散趋势。参考文献：（1）J.-M. Hily等人，《害虫管理科学》在线发表。doi:10.1002/ps.2074，2011年。（2）S. Miessner和G. Stammler，《植物病害防护杂志》117:162，2010年。（3）OEPP/EPPO，《EPPO A2类建议作为检疫性有害生物进行监管的有害生物清单》。2009 - 09版。从http://www.eppo.org/QUARANTINE/listA2.htm获取，2010年9月22日。（4）OEPP/EPPO，《报告服务》。第1期，2010年1月。从http://archives.eppo.org/EPPOReporting/2010/Rse-1001.pdf获取，2010年9月22日。
