Association and distribution of plant parasitic nematodes in peony (Paeonia lactiflora) fields of Korea.
An extensive survey for plant parasitic nematodes of peony plants were conducted in April 1998 and a total of 195 soil and root samples were collected from six different regions of the country. The surveyed area included research stations, private farms and hills. Analysis of samples revealed that 12 species: Meloidogyne hapla, M. incognita, Pratylenchus penetrans, Tylenchorhynchus claytoni, T. nudus, Helicotylenchus pseudorobustus, Criconemoides morgensis, Ditylenchus dipsaci, Discocriconemella hengsungica, Hemicycliophora koreana, Xiphinema pini and Aphelenchus avenae were associated with the rhizosphere of peony plants. Frequency and density of these nematodes varied in different regions. M. hapla was found to be the most frequent and prevalent in all the regions surveyed, whereas high frequency and density of C. morgensis, D. hengsungica and H. koreana was recorded in hilly regions.