An emerging root-knot nematode, Meloidogyne enterolobii: addition to the EPPO Alert List
The root-knot nematode Meloidogyne enterolobii was first described in China in 1983, in the Hainan Province on a tree species (Enterolobium contortisiliquum, Fabaceae). It was then reported from other regions in China, mainly on guava (Psidium guajava). More recently, it has been suggested that M. enterolobii was a senior synonym of Meloidogyne mayaguensis (Karssen et al., in preparation; Xu et al., 2004), a species which had been originally described in Puerto Rico in 1988 on aubergine (Solanum melongena). Since the 1980s, this nematode has increasingly been reported on a wide range of host plants from different parts of the world (e.g. Brazil, Cuba, Florida (US), South Africa). M. enterolobii has a very wide host range including important crops (e.g. tomato, bean, pepper, many ornamentals). It is considered as an aggressive root-knot nematode which is able to overcome resistance in many cultivars. Considering the potential importance of M. enterolobii and the fact that it has been intercepted approximately 10 times from 1991 to 2007 in the Netherlands (although the identity of the nematode could only be confirmed in 2007), the Dutch NPPO suggested that it should be added to the EPPO Alert List and kindly provided most of the information which was used to prepare the short article below. Finally, it must be noted that the presence of M. enterolobii has been reported in glasshouses in France (Blok et al., 2002) and Switzerland (Kiewnick et al., 2008) which clearly demonstrates that there are pathways for the introduction of this pest into the EPPO region.
Meloidogyne enterolobii (root-knot nematode)
Why: The NPPO of the Netherlands brought to the attention of the EPPO Secretariat the risk that Meloidogyne enterolobii (syn. M. mayaguensis) may present for the EPPO region. This nematode species has been intercepted by the Dutch NPPO on various commodities imported from different parts of the world. M. enterolobii has a wide host range and in particular, it is able to overcome the resistance of many important cultivars of tomato, soybean and sweet potatoes. Finally, its presence has been reported in a few glasshouse crops in France and Switzerland.
Where: In this distribution, the EPPO Secretariat has considered that M. mayaguensis was a junior synonym of M. enterolobii.
EPPO region: France (reported once from Concarneau, Bretagne region), Switzerland. In the Netherlands, M. enterolobii has been intercepted approximately 10 times (from 1991 to 2007) in imported plant material from Asia, South America and Africa. Findings before 2007 could only be confirmed in the second half of 2007 when full information needed for reliable identification became available. In Switzerland, unusual damage has recently been observed on glasshouse crops of tomato and cucumber. Typical symptoms of Meloidogyne were observed and molecular assays confirmed the presence of M. enterolobii in 2 glasshouses. Further studies will be carried out to delimit the extent of the infestation in Switzerland.
Africa: Burkina Faso, Côte d’Ivoire, Malawi, Senegal, South Africa.
Asia: China (Hainan, Guangdong).
North America: USA (Florida, first reported in 2002 on ornamentals and then in a commercial tomato field and a tropical fruit nursery).
Central America and Caribbean: Cuba, Martinique, Puerto Rico, Trinidad and Tobago.
South America: Brazil (Bahia, Ceara, Minais Gerais, Parana, Pernambuco, Piaui, Rio de Janeiro, Rio Grande do Norte, Sao Paulo), Venezuela.
On which plants: M. enterolobii is a polyphagous species. Although its precise host range is still unknown, it has been found on many different host plants including economically important crops such as: Capsicum annuum (pepper), Citrullus lanatus (watermelon), Coffea arabica (coffee), Glycine max (soybean), Ipomoea batatas (sweet potato), Lycopersicon esculentum (tomato), Nicotiana tabacum (tobacco), Phaseolus vulgaris (bean), Psidium guajava (guava), Solanum melongena (aubergine), ornamental plants (e.g. Ajuga, Brugmansia, Clerodendron, Tibouchina) and wild plants (e.g. Bidens pilosa). Experiments carried out in the Netherlands have also shown that Cactus, Ficus, Syngonium, Rosa and Vitis can also be host plants of M. enterolobii.
Damage: As with other root-knot nematodes, M. enterolobii can induce root galling and plant decline but it is considered to be particularly aggressive (i.e. by a combination of a high reproduction rate, induction of large galls and a very wide host range). In addition, the virulence displayed by M. enterolobii against several sources of resistance to M. incognita, M. javanica and M. arenaria makes it a potential threat. For example, M. enterolobii is able to overcome resistance in tomato cultivars carrying the resistance gene Mi-1.
Dissemination: As a root-knot nematode species, it can be easily transmitted with soil and plant root material.
Pathway: Soil and growing medium, plants for planting from countries where M. enterolobii occurs.
Possible risks: Recent reports of M. enterolobii in glasshouses in the EPPO region clearly demonstrate that it has the potential to enter Europe. It was also recently detected in the USA during routine regulatory sampling at ornamental nurseries in South Florida which has a comparable climate with Southern Europe. It is very likely that this species can survive in the warmer parts of the EPPO region and in glasshouses throughout the EPPO region. In addition, this species was detected on roses (plants for planting) originating from China (see EPPO RS 2008/107), thus suggesting that it can also survive slightly cooler temperatures. Once root-knot nematodes have been introduced, it is in general difficult to control or eradicate them.
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EPPO RS 2008/105
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Panel review date: -
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Entry date 2008-05
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Sources
Blok VC, Wishart J, Fargette M, Berthier K, Philips MS (2002) Mitochondrial DNA differences distinguishing Meloidogyne mayaguensis from the major species of tropical root-knot nematodes. Nematology 4, 773-781.
Brito JA, Stanley J, Cetintas R, Powers T, Inserra R, McAvoy G, Mendes ML, Crow B, Dickson D (2004) Identification and host preference of Mleoidogyne mayaguensis and other root-knot nematodes from Florida, and their susceptibility to Pasteuria penetrans. Journal of Nematology 36(3), 308-309.
CABI (2000) Distribution Maps of Plant Diseases no. 804. Meloidogyne mayaguensis. CABI, Wallingford (GB).
NPPO of the Netherlands (2008-06).
Fargette M, Davies KG, Robinson MP, Trudgill DL (1994) Characterization of resistance breaking Meloidogyne incognita-like populations using lectins, monoclonal antibodies and spores of Pasteuria penetrans. Fundamental and Applied Nematology 17(6), 537-542.
Kiewnick S, Oggenfuss M, Frey B, Roth I, Eder R, Frey JE (2008) Nouvelle espèce de nematode dans les serres suisses. Der Gemüsebau/Le Maraîcher no. 2, 7-9. http://www.db-acw.admin.ch/pubs/wa_cma_08_pub_10498_d.pdf
Rammah A, Hirschmann H (1988) Meloidogyne mayaguensis n.sp. (Meloidogynidae), a root-knot nematode from Puerto Rico. Journal of Nematology 20, 58-69.
Xu J, Liu P, Meng Q, Long H (2004) Characterisation of Meloidogyne species from China using isozyme phenotypes and amplified mitochondrial DNA restriction fragment length polymorphism. European Journal of Plant Pathology 110, 309-315.
Yang B, Eisenback JD (1983) Meloidogyne enterolobii n.sp. (Meloidogynidae), a root-knot nematode parasitizing pacara earpot tree in China. Journal of Nematology 15(3), 381-391.
Yang BJ (1984) The identification of 15 root-knot nematode populations. Acta Phytopathologica Sinica 14(2), 107-112 (abst.).
INTERNET (last retrieved 2008-05).
CABI (2008) Crop Protection Compendium. Meloidogyne mayaguensis. http://www.cabicompendium.org
Florida Department of Agriculture and Consumer Services (US) Pest Alert. The root-knot nematode, Meloidogyne mayaguensis prepared by Rammah and Hirschmann, 1988 (Nematoda: Tylenchida) by Brito J, inserra R, Lehman P, Dixon P in 2002 (updated in 2007). http://www.doacs.state.fl.us/pi/enpp/nema/mayaguensis.html
NAPPO Phytosanitary Alert System. News stories (2002-06-20). Root-knot nematode new to the US. http://www.pestalert.org/viewArchNewsStory.cfm?nid=192