Effect of Cropping Regime on Populations of Belonolaimus sp. and Pratylenchus scribneri in Sandy Soil

The host efficiencies of corn, sorghum, soybean, and wheat were compared for a Kansas population of Belonolaimus sp. under greenhouse conditions. In a related field study conducted in 1989 and 1990, the responses of Belonolaimus sp. and Pratylenchus scribneri populations to eight cropping regimes were monitored at depths of 0-30 and 31-60 cm in sandy soil. With the exception of alfalfa, all crop species examined supported substantial increases in populations of both nematodes. Largest nematode population increases in the field occurred in corn plots, whereas alfalfa did not allow reproduction by either species during the 2 years of observation. Soil populations of both nematodes remained at detectable levels after 2 years of fallow. The distribution of numbers of Belonolaimus sp. between soil depths varied with sampling date, whereas populations of P. scribneri were consistently concentrated in the top 30 cm of soil.