Effects of Dolomitic Limestone, Gypsum, and Potassium on Yield and Seed Quality of Peanuts1

Abstract

The interactive effects of dolomitic limestone, gypsum, and potassium on yield and seed quality of a Virginia-type peanut was investigated. Responses were assessed in field experiments using a split-plot design with varying rates and combinations of dolomitic limestone and gypsum as the main plots. Two rates of potassium applied at planting were used as the split plots. Treatment effects were measured by changes in soil mineral composition, mineral content of the plant and fruit, yield, seed maturity, and seed quality.Applications of dolomitic limestone increased soil pH and soil calcium levels, but did not improve seed quality or increase yields or kernel content of the fruits. Applications of gypsum improved seed germination, seedling survival, seedling vigor, and root growth. Dark plumule abnormality was reduced by addition of gypsum. Soil pH was reduced and chemical composition of peanut leaves, hulls, and seed was influenced more by gypsum than by either dolomitic limestone or potassium. Potassium was less detrimental to fruit yield and seed quality when applied in combination with gypsum. Two seedling abnormalities, watery hypocotyl and physiological root breakdown, were associated with low levels of seed calcium.