Sesbania Species as Green Manures for Rice
Green manuring has been practiced widely in Asia, where fields are often small but intensively managed. Many Asian cropping systems are based on rice cultivation. Because of the ability of Sesbania species to grow in heavy soils, withstand waterlogging and flooding, and tolerate soil salinity, they are often the preferred green manure crop for rice. As greenmanure, sesbanias are grown and plowed under in the same field in rotation with the crop to be benefited. They may also be used as greenleafmanure: green matter cut and brought from elsewhere to the field for burial. Green manure legumes are sometimes intercropped as a method of economizing time and space in intensive cropping patterns. Farmers in parts of South and Southeast Asia make use of field borders and miscellaneous areas to grow crops to provide green leaf manure. Early estimates of the yield response of rice to green manuring may have been low because of the low yield potential of traditional varieties.