PARENT SESSION
Poster Session 19: Biodiversity
Wednesday, August 10, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal
Xiphinema krugi, species complex or a complex of species?
Oliveira, Marcelo1, Ferraz, Luiz Carlos2, Neilson, Roy 3, 1 Instituto Biológico, Campinas, SP, Brazil2 ESALQ/USP, Piracicaba, SP, Brazil3 Plant Soil Interactions Research Programme, Dundee, Tayside, Scotland, UK
ABSTRACT- The underlying basis of biodiversity is manifested directly and indirectly, through studies of taxonomic relationships, and of growth, form, adaptation and function. With a decreasing taxonomic resource base, at some point the delineation of a "species", based solely on molecular data will have to be addressed. Such decisions in the future will have to consider the impact of intra- and inter-population variability. Although recognised in classical taxonomy, few if any molecular studies have dealt with this issue. As a result of inter-population morphological and morphometric heterogeneity, the taxonomic status of Xiphinema krugi (Nematoda: Longidoridae) has previously been questioned. Thus fourteen morphologically putative X. krugi populations were used as a model and subjected to both taxonomic and molecular analyses to compare and contrast inter-population variability. The molecular and classical taxonomic data yielded four congruent groupings. The study of X. krugi presented here clearly demonstrates the potential problems ahead for molecular based biodiversity/ecological studies. We have demonstrated the possibility that X. krugi, currently believed to be a morphologically variable single species is in fact, either a species complex comprising of four distinct genotypes or a complex of cryptic species. The use of emerging technologies in ecological studies not only presents opportunities to the ecologist but also challenges of interpretation and understanding at a resolution hitherto unknown.
Key words: biodiversity, nematode, soil ecology