Evaluation of Selected Nematicides for Control of Meloidogyne arenaria in Peanut: A Multi-Year Study

A 5-year study was conducted to evaluate the relative efficacy of at-plant application of aldicarb, carbofuran, ethvlene dibromide (EDB), ethoprop, oxamyl, and phenamiphos for control of the root-knot nematode [Meloidogyne arenaria (Neal) Chitwood] on 'Florunner' peanut (Arachis hypogaea L.). Each year EDB was applied at rates of 8.4 and 16.8 L/ha, ethoprop at 2.2 and 4.4 kg ai/ha, and the remaining nematicides at 1.1 and 2.2 kg ai/ha. All nematicides and rates reduced larval populations of the nematode in the soil, determined near harvest time, and increased yields. The low rate of all nematicides resulted in the highest ratio of yield increase to the amount of nematicide used. The relation between yield (Y) and nematicide rates (N) could be described by Y=Ym-e, where b and k are constants and Ym represents the maximal theoretical yield. Larval numbers in soil were negatively and linearly related to the amount of nematicide added. Highest average yields were obtained with applicatio