Population Dynamics of Meloidogyne arenaria Juveniles in a Field with Florunner Peanut

Abstract

The development of juvenile populations of Meloidogyne arenaria was studied for 3 years in a peanut field near Headland, Alabama. The field had been in peanut for the preceeding 7 years. Soil samples for the study were collected from 20 different sites in the 7-ha field. Each site consisted of a plot 2 rows wide and 20 m long. Soil samples were collected every 2-3 wk through the peanut-growing season (May-September). In the last year of the study (1985 season) samples were also taken after harvest at 1-2 month intervals. Samples were collected to a depth of 20-25 cm and consisted of 16-20 cores (2.5-cm-diam.) per site. The cores from each site were composited and a 100-cm subsample was used to determine juvenile populations. Juvenile numbers were low ( 50/100 cm soil) during the first 80 days after planting but increased rapidly through the last month before harvest. The relation between numbers of juveniles in soil (J) and days from planting to harvest (T) was best described each ye