Calcium level in the peanut fruiting zone as influenced by gypsum particle size and application rate and time

Abstract

Abstract The peanut requires a readily available source of Ca in the fruiting zone during fruit development. Field studies were conducted for three years on two soils to compare rates of fine and coarse gypsum material applied to peanuts shortly after planting and at early flowering in supplying Ca to the peanut fruit and its effect on yields. The fine and coarse gypsum was applied at three rates and at two different times in randomized complete block experiments. At approximately every four weeks, composite soil samples were collected at 0–5 and 5–10 cm depths and extracted with (0.05N HC1 + 0.025N H2 SO4) extractant. On the Lakeland soil fine gypsum applied at early flowering gave higher Ca levels at the 0–10 cm depth than coarse material applied shortly after planting or at early flowering. Yield data showed that at low rates coarse gypsum applied at planting was superior to early flowering application. In most instances on the Greenville soil, coarse gypsum applied at planting produced higher levels o...