Response of Five Peanut Cultivars to Gypsum Fertilization On Soils Varying in Calcium Content1

Abstract

Abstract Experiments were conducted to characterize the response to Ca of two recently released peanut (Arachis hypogaea L.) cultivars, ‘Tifrun’ and ‘Early Bunch’ and to compare their response to that obtained from ‘Florunner’, ‘Florigiant’, and ‘NC-Fla 14’. Gypsum (CaSO4•2H2O, approximately 72% CaSO4) was applied at rates of 0 and 1,121 kg/ha in a split plot design using the above cultivars. The experiment was conducted on Fuquay loamy sand low in Ca content and on Greenville sandy loam relatively high in Ca content. Yield, percent sound mature Kernels (% SMK), percent extra large kernels (% ELK), and percent oil in the seed were measured. The peanut cultivars differed in their response to soil Ca level and to Ca fertilizaton. Gypsum applications did not increase % SMK and yield of Florunner significantly when soil Ca content was low and pH adequate, whereas the other four cultivars produced large increases in these factors. Gypsum applications to the low Ca soil with high pH increased the percent oil 4.0% for all varieties every year. The response of Tifrun and Early Bunch to gypsum fertilization was similar to Florigiant and NC.FLA 14 Tifrun quality factors and yields were comparable to Florunner on the Greenville soil without supplementary Ca, whereas Ca fertilization of the Fuquay soil was necessary. Early Bunch was similar to Florigiant and NC-Fla 14 in both yield and quality factors.