Application Time and Effectiveness of Four Systemic Nematicides Against Meloidogyne arenaria on Florunner Peanuts

The effect of application time on the effectiveness of four systemic nematicides (aldicarb, carbofuran, oxamyl, and phenamiphos) for control of root-knot nematode [Meloidogyne arenaria (Neal) Chitwood] on Florunner peanuts (Arachis hypogaea L.) was determined in field experiments at Headland, Alabama. The nematicides were applied at planting time and at two, four, and eight weeks after planting. Each nematicide was studied in a separate experiment and was applied at rates of 1.1, 2.2, and 3.4 kg a.i./ha. Effectiveness of the treatments was compared to that of an untreated control and a fumigant control consisting of a planting time injection of EDB 90 (Soilborm(?) 90) at 18.7 l/ha. Results indicated that greatest yield increments were obtained when the nematicides were applied during the first two weeks of crop growth; lowest yields were obtained when treatments were effected at the blooming-early pegging stage of peanut development, eight weeks after planting. Applications of phenam