Nitrogen mineralization from fIowering- and maturity- stage green manures under plooded conditions after different upland periods

Abstract

Leguminous green manure (GM) is a nitrogen (N) resource that can replace chemical fertilizers (CFs) in rice production. The pattern of N mineralization from GM, which changes according to species, growth stage, and the timing of incorporation, affects rice growth and yield. Thus, the characteristics of N mineralization should be clarified to promote the appropriate use of GM. The objectives of this study were to clarify the patterns of N mineralization from flowering- and maturity-stage GMs under flooded conditions after different upland periods, and to evaluate the denitrification loss occurring during the upland periods. Nitrogen mineralized from three species of GMs collected at both the flowering and maturity stages was measured through incubation tests.