The site selected for this study, which has a resident population of the peanut root-knot nematode (M. arenaria race 1), was cropped to peanut the previous year. On 7 Mar, a blended fertilizer containing 30 lb N+60 lb P+60 lb K/A was broadcast. Afterthe rows were laid off with a KMC strip tillage unit, corn varieties were sown on 19 Mar. Weed control was obtained with an application of Atrazine at 2 qt/A on 27 Mar. A topdressapplication of 120 lb/A of N + 20 lb/A of sulfur on 14 Apr was followed a second topdress of 80 lb/A of N + 20 lb/A of sulfur on 2 May. Between 3 May and 9 Aug, the corn received a total of 13.5 in of water via a center pivot irrigation system. The experimental design was a randomized complete block with four replications. Individual plots consisted of two 30-ft rows on 3-ft centers. Soil samples, which were collected on 12 Apr (Pi)and 10 Sep (Pf), were processed using the sugar flotation method. Peanut root-knot populations are expressed as the number of juveniles (J2) per 100 cm3 of soil. For each corn variety, the reproduction (Pf/Pi) ratio for thepeanut root-knot nematode was calculated by dividing the Pf (final population) value by the Pi (initial population value) for each plot and then dividing by the number of replications. Plots were harvested on 16 Aug. Significance of treatment effects were tested by analysis of variance and Fisher’s protected least significantdifference (LSD) test (P<=0.05).
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