Yields and Responses to Lime and Potassium Fertilizer in Different Cropping Years in Uganda

Publisher Website
Google Scholar
Abstract
SUMMARY: Trials on ferrallitic soils in Uganda showed that crops responded to lime after the first year of cropping on soils which had a pH up to 6·0, and to potassium on soils which had an extractable K level up to 18 mg 100 g−1. Soil and leaf analyses indicated that responses to lime on soils of pH above 5·2 were due to an increase in phosphate availability. Low yields at several sites in the first year were apparently due to immobilization of nutrients during rapid mineralization of soil organic matter. In later years soil organic matter did not decline appreciably, and yields dropped only at sites where potassium or minor element deficiencies apparently developed.