Geographical Distributions of Rotylenchulus reniformis, Meloidogyne incognita, and Tylenchulus semipenetrans in the Lower Rio Grande Valley as Related to Soil Texture and Land Use.

A survey was conducted over a 22-year period to evaluate the influence of soil texture and land use on the geographical distributions of Rotylenchulus reniformis, Meloidogyne incognita, and Tylenchulus semipenetrans in the lower Rio Grande valley. The distributions of R. reniformis and M. incognita were related to soil texture, whereas T. semipenetrans occurred wherever host plants were present regardless of soil texture. The incidence of M. incognita was greatest in elevated sandy loams and moderately well-drained silts of modern flood terraces of the Rio Grande river. Rotylenchulus reniformis occurred predominantly in clay silts and clays of ancient flood terraces. Clay loams and sandy clay loams of the central, irrigated portion of the lower Rio Grande valley appeared favorable for M. incognita and R. reniformis. Differences between the geographical distributions of these two species could not be attributed to host crops.