The influence of calcium within the fruiting zone on the initiation of peanut pod rot was evaluated in laboratory, greenhouse and microplot studies. Peanut (Arachis hypogaea L.) plants were raised under gnotobiotic conditions to determine if a calcium deficiency alone can be considered a primary cause of the disease. The relative distribution of K, Mg, and Ca within the pericarp of fruit from the experiments was determined. Greenhouse and microplot studies were conducted to evaluate the effect of calcium sulfate in reducing pod rot in soil containing increasing populations of Pythium myriotylum. The relationship of calcium rates applied at early bloom to the calcium content of the pericarp and the level of disease was determined.Plant Patholog
