Morphometric and molecular characterization of populations of Pratylenchus kumamotoensis and P. pseudocoffeae (Nematoda, Pratylenchidae) newly recorded in Korea.

At least 70 species of root-lesion nematodes, Pratylenchus spp., have been identified worldwide, many of which are serious pests of various agricultural crop plants. In Korea, only 14 species have been recorded in vegetable and fruit fields. Here, we report two new records of root-lesion nematode species in Korea based on morphometric and molecular methods. Soil samples were collected from chrysanthemum cultivars in various regions. Morphometric diagnosis showed that two new records for Korea: Pratylenchus kumamotoensis in Chilgok County and Pratylenchus pseudocoffeae in Geumsan County. In addition, molecular diagnosis using the two sequences of the internal transcribed spacer (ITS) and the D2-D3 region of ribosomal DNA showed that these two species were most similar with those from Japan, Costa Rica and USA. The similarities of the ITS and D2-D3 sequences were 99.85 and 99.74%, respectively, for Pratylenchus kumamotoensis and 99.99 with Costa Rica populations and 99.86% with USA populations, respectively, for Pratylenchus pseudocoffeae. To our knowledge, this is the first report of two species in Korea.