Legumes as green manures and cover crops.

This chapter focuses on the main green manure and cover crop legumes such as Canavalia, Crotalaria and Mucuna species. The ability of these legumes to fix N2 in abundance is also discussed. The accumulation of N and N2-fixation in legume green manures in rice systems and the release of N and recovery by the rice crop are highlighted. Finally, the current use, benefits as well as problems of green manures are also explored.