Serge Bouzinac

Improvement of cropping systems by integration of rice breeding: a novel genetic improvement strategy

Rice improvement is based to an increasing extent on ever-sharper genetic analysis to the detriment of classical breeding, which is disappearing. Analytical genetics are very promising, but they cannot replace integrated and finalized breeding. Little attention has been paid to improving participatory rice breeding methods for subsequent integration into sustainable cropping systems. Special methodological initiatives are required to ensure the success of this breeding-agronomy integration. This integration of inexpensive breeding methods has increased the biodiversity of rice: low temperature and drought tolerant upland rice varieties for mountain areas, and polyvalent varieties, which have the ability to grow in both rainfed or irrigated conditions, they are perfectly adapted to improved cropping systems and to beneficiaries’ needs and preferences. These preliminary results on this integration demonstrate that the present approach is relevant.

Direct seeding on plant cover : sustainable cultivation of our planet's soils

Savannas (cerrados) in the humid tropics of Brazil cover an area of 200 million ha, a quarter of which is under intensive agriculture. Tillage techniques used in the cerrados have resulted in serious failures and highly degraded soils. CIRAD and its public and private Brazilian partners have developed direct seeding systems over permanent mulch or plant cover. Seven million ha are currently being cropped with direct seeding strategies in the cerrados as an upshot of this research. Three systems have been developed: continuous grain production with two annual crops, followed by temporary dry-season grazing; production of grain crops and sward for mulching and temporary grazing; and an annual sequence of grain crops on live forage cover. These systems cost-effectively produce high stable crop yields, function like natural ecosystems, and require that farmers be constantly innovative and flexible.