Abstract

Studies were conducted in 2004 and 2005 to evaluate the effect of redroot pigweed on peanut. Redroot pigweed aboveground dry weight was 44, 42, 40, 38, 35 and 30 g plant^-1 at density of 0.2, 0.5, 0.8, 1.2, 2.3, or 4.7 plants m^-1 of crop row. Peanut yield decreased as weed density increased. Yield reduction under redroot pigweed interference was 4.1 and 63.9% at 0.2 and 4.7 plants m^-1 crop row, respectively. Theresults suggest that redroot pigweed is a strong competitor with peanut and should be controlled to prevent high peanut yield loss.

Key words: Competition, Amaranthus retroflexus, density, interference, peanut, biomass.