Plant Protection: A Phylogenetic Tree of Nematodes

Researchers at the Wageningen University in the Netherlands, working with scientists from the Dutch Plant Protection Service, have published the largest nematode phylogenetic tree to date. The researchers used a specific segment of the ribosomal DNA that allowed them to distinguish between most nematode species.

Nematodes are the world's most numerous groups of animals with two to 20 million individuals, normally smaller than one millimeter, per square meter of soil. Some nematodes are beneficial, for instance members of the Steinernematidae and Heterorhabditidae families are being used to control insect pests. However, most useful species share a strong resemblance to pathogenic species. This makes finding out which nematodes are present in a soil of a given area an extremely time-consuming and a specialist task. Accurate identification is vital to developing a successful management program against plant parasitic nematodes.

"[The phylogenetic tree] contains over 1,200 species and is entirely based on the analysis of DNA sequence data. It is relatively straightforward - and in fact we've shown it already - to define species-specific DNA barcodes on the basis of this data set that allows for the detection of nematodes in soil with an unprecedented accuracy," the scientists wrote in the paper published by Nematology.

Download the paper at http://dx.doi.org/10.1163/156854109X456862 For more information, read http://www.wur.nl/UK/newsagenda/news/On_the_origin_of_nematodes__A_phylogenetic_tree_of__the_
worlds_most_numerous_group_of_animals.htm