Nematode Populations in Corn Plots Receiving Different Soil Amendments

The magnitude of nematode populations in corn plots receiving manure, lime, or a fertilizer supplying N-P-K was compared with populations in corn plots not receiving manure, lime, or an N-P-K fertilizer. Pratylenchus spp. populations were highest in N-P-K fertilized plots and in manured plots. Helicotylenchus microlobus were highest in in plots in which no N-P-K had been applied. Xiphinema americanum populations were highest in limed plots. Seasonal population patterns for the three nematodes appeared to be characterized by two peaks, one in the early spring prior to the planting of corn, and the other in the late summer or fall related to the growth of corn. Only Pratylenchus spp. appeared to feed endoparasitically in corn roots