Velvetbean for the Management of Root-Knot and Southern Blight in Peanut

The value of Florida velvetbean (Mucuna deeringiana) as a rotation crop for the management of root-knot nematode (Meloidogyne arenaria) and southern blight (Sclerotium rolfsii) in 'Florunner' peanut (Arachis hypogaea) was studied from 1989-1991 in a field experiment in southeastern Alabama. The field had been in peanut with winter fallow for the preceeding 10 years and was heavily infested with M. arenaria. In 1991, the yield of peanut following 2 years of velvetbean (V-V-P) was 47% higher than the yield of monoculture peanut without nematicide [P(-)] and 20% higher than that of monoculture with aldicarb [P(+)] applied at-plant (0.302 g a.i./m row in a 20-cm band). Compared with peanut plots, plots with velvetbean in 1989 and 1990 had low populations of M. arenaria juveniles in soil at peanut harvest. In 1991, M. arenaria juvenile populations in soil were lowest in plots with the V-V-P rotation and highest in those with P(-); numbers of juveniles in plots with P(+) were lower than in