Brazilian savannas or "cerrados", which cover an area of 200 million ha, possess a high potential for agricultural production. Upland rice has been used as a pioneer crop to open these areas for cultivation, and covered an area of more than 4.5 million ha during the 1970s and 1980s. The cultivars used in this system were tall, japonica types, with good tolerance to drought stress and a traditional bold grain type. Subsequently, the shift of rice to more favorable production zones and a change in consumer grain preference has required the development of a new class of aerobic rice cultivars. These were derived from crosses between upland and lowland cultivars, and they combine adaptation to unflooded (aerobic) soils with responsiveness to applied inputs. Crop financing policies take into consideration the climatic risk for different savannah micro-regions, which has been established using water balance models and GIS. Research recommendations have been developed to minimize climatic risk through appropriate date of planting and choice of variety. New varieties, japonica × indica derivatives, with improved plant type and duration and with desirable grain appearance and cooking behavior, provide an economically attractive option for farmers in stable cropping systems. Such varieties have been adopted by farmers both as a regular component of grain cropping systems and as a crop to assist in renewal of degraded pasture. These aerobic rice systems help meet national demand for rice without the levels of water use and investment in infrastructure required for irrigated lowland rice production. © 2005 Elsevier B.V. All rights reserved.
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