Direct seeding mulch-based cropping systems (DMC) in Latina America

Areas permanently cultivated under DMC systems (Direct seeding mulch-based cropping systems, which are part of the family of practices known as Conservation Agriculture) have increased remarkably in Latin America over recent decades, reaching around 50% of total cropped area in Brazil, Paraguay and Argentina. These systems have been developed to counteract soil degradation and to achieve more sustainable grain production. Under tropical and sub-tropical conditions the efficiency of such systems increases with the introduction of multi-functional cover crops growing in rotation with the main commercial crops or whenever climatic conditions are too risky for planting a commercial crop. The introduction of cover crops leads to a better utilization of available natural resources throughout the year, more biomass production, permanent soil protection and higher organic restitutions to the soil. DMC systems also offer environmental, economic and agronomic advantages to farmers. Nevertheless they are quite complex systems and their adaptation to specific local constraints and conditions is not straightforward, especially in the case of smallholder, resource-limited agriculture. Specific approaches have been designed, based on systemic and participatory research principles, to create, adapt and disseminate these systems among farmers by working mainly under actual farming conditions. The active participation of farmers and their organizations is fundamental at all stages, as well as that of other key stakeholders of the agricultural sector. Farmers, researchers and their key partners still need to meet several challenges to further increase the success and large-scale adoptability of DMC systems. These include understanding and enhancing the underlying biological processes, creating DMC systems less dependant on chemicals or external inputs, as well as fitting these systems for conditions of close interactions between agriculture and livestock production. These last two challenges are especially true for small-scale farmers operating in marginal environments. Also, the knowledge and experience about DMC systems functioning, creation and management, and about adoption stories, needs to be better systematized and made available through the development of synthetic tools such as data bases, dynamic models and global indicators of DMC system functioning and impact, as well as through enhanced networking among the different stakeholders. Putting together these various pieces will facilitate the conception and implementation of new projects aiming to enhance DMC adaptation and adoption.