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47Th Annual Meeting of the Organization of Nematologists of Tropical America / 47 Reunión Anula De La Organización De Nematólogos De Los Trópicos Americanos

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47Th Annual Meeting of the Organization of Nematologists of Tropical America / 47 Reunión Anula De La Organización De Nematólogos De Los Trópicos Americanos 47TH ANNUAL MEETING OF THE ORGANIZATION OF NEMATOLOGISTS OF TROPICAL AMERICA / 47 REUNIÓN ANULA DE LA ORGANIZACIÓN DE NEMATÓLOGOS DE LOS TRÓPICOS AMERICANOS “Plaza América” Conventions Center / Centro de Convenciones “Plaza América” Varadero, Cuba 17-22 May, 2015 / 17 al 22 de mayo del 2015 Members of the International Scientific Committee ONTA/ Miembros del Comité Científico Internacional ONTA/\ Dr. Larry Wayne Duncan, USA (President) Prof. Alejandro Esquivel MSc., Costa Rica (Vice-president) Dr. C. Overstreet, USA Dr. Danny Coyne, Kenia Dr. Deborah A. Neher, USA Prof. Edward McGawley PhD., USA Dr. Ernesto San Blas, Venezuela Dr. Juan C. Magunacelaya, Chile Dr. Luis V. López-Llorca, España Prof. Nahum Marbán-Mendoza PhD., México Dr. Nicole Viaene, Bélgica Dr. Patricia Stock, USA Dr. Paula Agudelo, USA Dr. Pierre Abad, Francia Dr. Raquel Campos-Herrera, Suiza Dr. Renato Inserra, USA Dr. Ricardo Holgado, Noruega Dr. Rosa Manzanilla-López, Reino Unido Dr. Soledad Verdejo-Lucas, España Prof. Wilfrida Decraemer PhD., Bélgica Members of the National Scientific Committee/ Miembros del Comité Científico Nacional Dr. Mayra G. Rodríguez Hernández (Presidenta) Dr. Emilio Fernández Gonzálvez Dr. Hortensia Gandarilla Basterrechea Dr. Iván Castro Lizazo Dr. Cs. Leopoldo J. Hidalgo Díaz Dr. Ricardo Cuadra Molina ABST 1 ABST 2 NEMATROPICA Vol. 45, No. 2, 2015 ORAL PRESENTATIONS / PRESENTACIONES ORALES PERSPECTIVES IN NEMATOLOGY NEMATODE COMMUNITIES AS RESEARCH, CROP PROTECTION AND ECOLOGICAL INDICATORS OF ECOSYSTEM FOOD SECURITY [PERSPECTIVAS EN HEALTH [COMUNIDADES DE NEMATODOS LA INVESTIGACIÓN NEMATOLOGICA, COMO INDICADORES ECOLÓGICOS DE PROTECCIÓN DE CULTIVOS Y LA SALUD DEL ECOSISTEMA] SEGURIDAD ALIMENTARIA] 1 Deborah A. Neher * A. Ciancio1* 1Department of Plant & Soil Science, University of 1Istituto per la Protezione Sostenibile delle Piante, Vermont, Vermont, USA Consiglio Nazionale delle Ricerche, Bari, Italy *E-mail: [email protected] *E-mail: [email protected] Nematodes have attributes that make them useful as Nematology originated as a specific monophyletic ecological indicators. Various kinds of perturbations science stemming from more general disciplines to soils, such as addition of mineral or organic like zoology and natural history, and early studies nitrogen fertilizer, cultivation, and accumulation concerned descriptions and taxonomy. Research of heavy metals affect the species richness, trophic work was intensified in the 50s, when monocultures structure and successional status of nematode of industrial cropping systems required effective communities. Through a series of experiments on nematode management tools. Actual research is part sampling and experimental design at various spatial of advanced endeavours, largely multidisciplinary, scales, it is concluded that maturity and trophic integrating approaches ranging from ecology to diversity indices are capable of differentiating among molecular biology and genome studies. As defined sampling sites better and more efficiently than by FAO, food security means that all people have the measures based on populations or ratios of individual right to sufficient and safe food. A fundamental ethic trophic groups. Maturity and trophic diversity indices committment of research in agriculture is then how measure different aspects of soil communities and are to satisfy, in space and time, any dietary need and complementary when used together. ‘Maturity’ is a preference for a healthy life. A key issue concerns measure of successional status and trophic diversity the transfer and application of main achievements measures food web structure. There are two major and knowledge in other regions of the world, with impediments to implement nematode communities in different needs. Challenges include facing the large-scale environmental monitoring programs, i.e., consequences of demography and climate changes or ecological interpretation and accessibility to non- other threats present. We have to recognize that the specialists capable of identifying a multitude of free- magnitude of the problems is much more demanding living nematode taxa. Molecular probes are one way to than ever in the history of agriculture, in terms of expedite identification and enumeration of nematodes research and technology transfer. Given the social, within whole community samples. Although this political or economic roots of many food security approach is available to non-taxonomists, it does not threats, nematology may only partially contribute address concerns about interpretation and potential to reach this goal. Actual advances of scientific errors in assignments. Alternatively, nematode knowledge, spanning from genomes to plant community indices would be more cost-effective biology and ecosystem services are, however, very and interpretable if ambiguous genera were removed significant. To solve or at least alleviate some of the and indices reduced to include sentinel taxa with food security problems affecting many rural systems known sensitivity or response to specific types of and communities, nematology may contribute to disturbance. Sentinel taxa will represent a subset of reach specific milestones through the international nematode communities but require knowledge of cooperation. Fundamental are freedom and right for species assemblage patterns under different scenarios access to education and scientific information for of management practices, which often represent a everyone, and the support of global efforts aiming at complicated mixture of abiotic and biotic factors. an independent production of knowledge. Once sentinel taxa are identified, subsequent studies are needed to verify their sentinel status to determine the geographic or ecological range of their utility. 47TH ANNUAL MEETING OF THE ORGANIZATION OF ABST 3 NEMATOLOGISTS OF TROPICAL AMERICA INTEGRATED TAXONOMIC STUDIES REVERSE TAXONOMY, PHYLOGENY, HIGHLIGHT THE VIRUS VECTOR FAMILY AND DNA BARCODING TO ILLUMINATE TRICHODORIDAE AS A SOURCE OF MANY THE DIVERSITY OF APHELENCHOIDES UNKNOWN CRYPTIC SPECIES IN SPAIN [TAXONOMÍA INVERSA, FILOGENIA, [ESTUDIOS TAXONÓMICOS INTEGRADOS Y CÓDIGO DE BARRAS GENÉTICO DESTACAN A LA FAMILIA VECTORA DE PARA ILUSTRAR LA DIVERSIDAD DE VIRUS TRICHODORIDAE COMO FUENTE APHELENCHOIDES] DE MUCHAS ESPECIES CRÍPTICAS Alcides Sánchez-Monge1*, Toon Janssen1, and Wim Bert DESCONOCIDAS EN ESPAÑA] Ghent1 1,2 3 3 W. Decraemer *, J. E. Palomares-Rius , C. Cantalapiedra , 1 3 University, Department of Biology, Nematology Research and P. Castillo Unit, Ledeganckstraat 35, B-9000 Ghent, Belgium 1,2Royal Belgian Institute of Natural Sciences, Brussels, 2 *E-mail: [email protected], toon.janssen@ugent. Belgium; Ghent University, Biology Department, be, [email protected] Ghent, Belgium; 3Instituto de AgriculturaSostenible (IAS),Consejo Superior de InvestigacionesCientíficas Aphelenchoidea comprises nematodes with a (CSIC), ceiA3, Apdo. 4084, 14080-Córdoba, Spain high variety of feeding types and ecology roles; *E-mail: [email protected] mycophagous, predators as well as insect and plant parasites are represented in this superfamily. Among The polyphagous root ectoparasitic family plant-parasites, species of Bursaphelenchus and Trichodoridae occurs worldwide. Its major pest Aphelenchoides have an important impact on several status is as vector of Tobraviruses, especially in the plant species. Selected taxa of both genera have been didelphic genera Paratrichodorus and Nanidorus, characterized and the resulting molecular analyses with 27% and 28.6% of vector species, respectively. revealed a monophyletic origin of Bursaphelenchus Current study focused on the biodiversity of but the phylogeny and the evolution of the plant- Paratrichodorus from southern Spain. Identification parasitism within Aphelenchoidesis not yet well of Paratrichodorus species is hampered even more understood. Moreover, species of the genera than in Trichodorus, by their largely conserved Laimaphelenchus and Schistonchus are found within morphology and restricted number of diagnostic the clade of Aphelenchoides, confirming its origin is morphological features, overlap of morphometrics, not monophyletic and that the family needs major difficulty to fix specimens properly and co-occurrence revision. Little is known about the phylogenetic of at least two species in the same soil sample, often relationship depicted by molecular data in relation with a restricted number of specimens. Molecular to the morphology-based classification. For example, analyses based on nuclear ribosomal RNA genes four groups of Aphelenchoides (based on the tail (D2-D3 expansion segments of 28S and partial 18S shape) are commonly referred in literature, but gene) clearly directs the comparative morphological such grouping lacks molecular evidence despite study while the morphology and morphometrics its taxonomical importance. Furthermore, some helps the molecular research to interpret the results molecular data of Aphelenchoides spp. in GenBank when dealing with co-occurrence of several species. appear to be completely wrong, but these data cannot Surveys for trichodorids were carried out in cultivated be checked because morphological vouchers are and natural habitats in southern Spain. The integrative absent. To tackle these problems, we will record taxonomic approach revealed several new species the detailed morphology of several Aphelenchoides belonging to two main clades: (1) a P. hispanus specimens from different locations and several related group, characterized
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