Church G T
U.S. Horticultural Research Laboratory, USDA-ARS, Fort Pierce, FL 34945.
Plant Dis. 2005 May;89(5):527. doi: 10.1094/PD-89-0527B.
The state of Florida is the largest producer of fresh market tomato (Lycopersicon esculentum L.) in the United States with 2003 yields of 634 million kg on 17,700 ha valued at 516 million dollars. Effective crop management is essential for production of vegetables in Florida because of the presence of intense pest pressure. The identification of the pests present is the first step in the development of a successful IPM (integrated pest management) program. Root-knot nematodes (Meloidogyne spp.) are common nematodes that parasitize vegetables in Florida and cause significant yield reductions when not properly managed. In 2003 field experiments, soil was collected from two research farms in Saint Lucie and Seminole counties in Florida. Galling caused by root-knot nematode was observed on tomato at both locations. Since females suitable for identification are difficult to obtain from field-grown roots, field soil was placed in pots in the greenhouse and planted with Lycopersicon esculentum cv. Rutgers. Standard morphological techniques, differential host tests, and isozyme phenotypes were used in nematode identification. Female root-knot nematodes were extracted from tomato roots and placed in extraction buffer (10% wt/vol sucrose, 2% vol/vol Triton X-100, 0.01% wt/vol bromophenol blue). The females were crushed, loaded on a polyacrylamide gel, and separated by electrophoresis using the PhastSystem (Amersham Biosciences, Piscataway, NJ). The activities of malate dehydrogenase and esterase enzymes were detected using standard techniques. Isozyme phenotypes consistent with Meloidogyne incognita (Kofoid and White) Chitwood and M. javanica (Treub) Chitwood as well as with the newly described M. floridensis Handoo (1) were observed at both locations. To our knowledge, this is the first report of M. floridensis naturally occurring on tomato in Florida. The identification and distribution of M. floridensis in vegetable production fields is important for disease management throughout the state since the host range is likely different from other Meloidogyne spp. Reference: (1) Z. A. Handoo et al. J. Nematol. 36:20, 2004.
佛罗里达州是美国鲜食市场番茄（Lycopersicon esculentum L.）的最大生产地，2003年在17700公顷的土地上收获了6.34亿公斤番茄，价值5.16亿美元。由于病虫害压力巨大，有效的作物管理对于佛罗里达州的蔬菜生产至关重要。识别存在的害虫是制定成功的综合虫害管理（IPM）计划的第一步。根结线虫（Meloidogyne spp.）是佛罗里达州常见的寄生在蔬菜上的线虫，若管理不当会导致大幅减产。在2003年的田间试验中，从佛罗里达州圣露西县和塞米诺尔县的两个研究农场采集了土壤。在这两个地点的番茄上均观察到了根结线虫引起的根瘤。由于难以从田间生长的根部获取适合鉴定的雌虫，因此将田间土壤置于温室的花盆中，并种植了佛罗里达大学罗格斯分校培育的番茄品种（Lycopersicon esculentum cv. Rutgers）。使用标准形态学技术、鉴别寄主测试和同工酶表型对线虫进行鉴定。从番茄根中提取雌根结线虫，并将其置于提取缓冲液（10%重量/体积蔗糖、2%体积/体积吐温X-100、0.01%重量/体积溴酚蓝）中。将雌虫碾碎，加载到聚丙烯酰胺凝胶上，使用PhastSystem（Amersham Biosciences，皮斯卡塔韦，新泽西州）通过电泳进行分离。使用标准技术检测苹果酸脱氢酶和酯酶的活性。在这两个地点均观察到了与南方根结线虫（Meloidogyne incognita (Kofoid and White) Chitwood）、爪哇根结线虫（M. javanica (Treub) Chitwood）以及新描述的佛罗里达根结线虫（M. floridensis Handoo (1)）一致的同工酶表型。据我们所知，这是佛罗里达州番茄上自然发生佛罗里达根结线虫的首次报道。佛罗里达根结线虫在蔬菜生产田中的鉴定和分布对于该州的病害管理很重要，因为其寄主范围可能与其他根结线虫属不同。参考文献：(1) Z. A. Handoo等人，《线虫学杂志》36:20，2004年。
