Comparison of Agricultural and Power Plant By-Product Gypsum for South Texas Peanut Production

Field studies were conducted in 1998 and 1999 at one location in Atascosa and two locations in Wilson County to evaluate the effects of power plant by-product gypsum in comparison with agricultural gypsum applied to peanuts at planting or pegging.  The Atascosa County site contained moderate to high calcium (Ca) levels while the Wilson County site was low to moderate in Ca.  No differences in southern blight, Rhizoctonia pod rot disease control, peanut yield, or grade were noted with each gypsum source.  Gypsum reduced disease development at two of three locations but only increased peanut yield or grade at one of three locations.