Incidence and Economic Importance of Plant-Parasitic Nematodes on Peanut in Texas

The distribution of plant-parasitic nematodes in five Texas peanut producing counties was determined during 1985 and 1986 growing seasons. Criconemella, the most frequently detected genus, was present in 83.4% of the samples; evidence of crop damage was not observed. Meloidogyne arenaria was detected in 15.5% of the samples. In microplot tests, there was a significant negative relationship between initial populations of M. arenaria and peanut yields; a linear model estimates a 10% yield loss with initial populations of 44–83 M. arenaria/500 cm³ soil. At least 10% of the survey samples were estimated to have root-knot nematode populations exceeding that necessary for a 10% yield loss. Other parasitic genera found in the survey were Pratylenchus (15.7% of the samples) and Belonolaimus (0.8% of the samples). While pod symptoms of Pratylenchus damage were observed, reliable yield loss estimates can not be made with existing data.