Nematropica (2001) 31, 195-209
L.K. Carta, A.M. Skantar and Z.A. Handoo (2001)
Molecular, morphological and thermal characters of 19 Pratylenchus spp. and relatives using the D3 segment of the nuclear LSU rRNA gene
Nematropica 31 (2), 195-209
Abstract: Gene sequences are provided for the D3 segment of the large subunit rRNA gene in Pratylenchus agilis, P. hexincisus, P. teres, and P. zeae. They were aligned with the closest comparable previously published molecular sequences and evaluated with parsimony, distance and maximum-likelihood methods. Different outgroups and more taxa in this study compared to a previous D3 tree resulted in improved phylogenetic resolution. Congruence of trees with thermal, vulval and lip characters was evaluated. A tropical clade of Pratylenchus with 2 lip annules was seen in all trees. Maximum-Parsimony and Quartet-Puzzling Maximum-Likelihood trees, with ambiguously-alignable positions excluded and Radopholus similis as an outgroup, had topologies congruent with species possessing 2, 3 or 4 lip annules. An updated sequence for Pratylenchus hexincisus indicated it was an outgroup of P. penetrans, P. arlingtoni, P. fallax and P. convallariae. Pratylenchus zeae was related to P. neglectus in a Neighbor-Joining tree, but was equivocal in others. The relatives of P. teres were P. neglectus and Hirschmanniella belli rather than morphometrically similar P. crenatus. The P. agilis sequence is more closely related to the nearly identical sequences of P. pseudocoffeae and P. brachyurus, than to that of P. scribneri, which is a species closely related morphologically.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): Lynn K. Carta, Zafar A. Handoo, Andrea M. Skantar
Research topic(s) for pests/diseases/weeds:
identification/taxonomy
molecular biology - genes
