About 250 farmers have tried comparing cereal cultivation under direct seeding mulch-based cropping systems (DMC) against the traditional cropping practices from year 2001 to 2004. The on-farm tested systems include mixed cropping of a cereal (maize, sorghum, millet) and a cover crop (mucuna, brachiaria, crotalaria, cowpea, dolichos). These mixed cropping practices are done for the following objectives: 1) Produce aboveground biomass to build-up mulch for the following season's crop (mainly cotton). 2) Soil improvement through the physical and chemical (produce N) contribution of the associated plants. 3) Forage production. 4) Weed control. 5) Protect the soil surface against erosion and rain impact. 6) Produce consumable grains for man and animals. Up till present the tested plants meet the above objectives differentially and are adapted to the local agro climatic conditions of North Cameroon (rainfall from 700 to 1200 mm). Thus Brachiaria ruzisiensis produces aboveground biomass in quantities (4-5 t/ha even under mixed cropping) and quality (persisting as mulch for over one year after production). Further, it is very efficient in controlling Striga and is a good forage crop. However, it can impoverish the soils if its biomass is exported several times without any fertiliser supplements since it is not a nitrogen fixing plant. On the contrary Crotalaria retusa is a nitrogen fixing plant and therefore enriching the soils. This plant is less palatable to animals and therefore advantageous to farmers who cannot protect their farmland from pasturing animals in the dry season. It is equally very efficient in controlling weeds. Four years of experimentation has enabled us to produce practical recommendations in mixed cropping on the following : sowing date, crop type, tolerance to herbicides, competition with cereals, etc. This experimentation has also enabled us to see how the various plants tie with the above-mentioned objectives. On-going research work is on the following: 1) Diversifying the range of plant material available, focusing on local varieties. 2) Extending these cropping techniques to cover vertisols covering tens of thousands of hectares in North Cameroon. 3) Introducing these plants at the beginning and at the end of the cycle of the main crop in order to better use early and the late rains.

Principes et clés pour l'action. Restitution de la formation UEPG/Cirad au Brésil par le collectif SCV.

Petit rapport sur DMC dans le monde pour monter un plan d'action pour le Sud-Est asiatique.

Direct seeding Mulch based Cropping systems (DMC) under Eau Sol Arbre (ESA) project Since 1994 Sodecoton, through the DPGT and ESA projects, has popularised several techniques for soil fertility maintenance on over 150 000 ha in the north of Cameroon (Sadou et al, 2005): This include anti-erosion management (weeded bands, stone lines and reach,....), leguminous trees planting and preservation in cultivated fields (preservation of Acacia albida tree), promotion of organic manure. In addition to these large scale extension actions, conservation agriculture (CA) was experimented through cropping systems improvement approach developed by CIRAD, based on DMC (Direct seeding - Mulchbased - Cropping systems) practices. From 2001 to 2005, DMC techniques were designed and tested by more than 70 farmers in their fields in North and Far North provinces of Cameroon.

Farming systems throughout the Lao PDR have changed drastically over the last 15 years due to a range of factors. In some areas where market forces are prevalent, shifting cultivation systems have given way to more conventional high-input agricultural systems. In other more remote areas, the traditional swidden system with long rotations has been put under pressure primarily due to modification of land access and increasing population pressure. In southern Xayabury in the Mekong corridor, where there is access to the Thai market, land preparation has become based on burning residues and ploughing on steep slopes. Because of the environmental and financial costs of land preparation, farmers are shifting to herbicides, which lead to chemical pollution, while crop residues and weed mulch are usually burned, thereby increasing mineral losses and erosion on bare soil. In mountainous areas such as Xieng Khouang Province, the rationale of shifting cultivation is collapsing as farmers use land for longer periods of cropping and return more frequently to each field. A holistic research approach has been implemented in Xayabury and Xieng Khouang to find direct seeding mulch-based cropping (DMC) systems that are compatible with farmers' strategies and which can be reproduced inexpensively on a large scale. The methodological framework, based on five main components, emphasises the process of adaptation and validation by farmer groups, meaning that priorities are defined by smallholders in light of the constraints of their farming systems and the overall environmental conditions.

la pratique des associations culturales frappe par sa généralisation : dans les zones exondées en permanence, elle concerne de 65 à 85 % des exploitants agricoles. Les objectifs de cet article sont: (i) de caractériser l'importance et la diversité des systèmes d'associations mis en œuvre ; (ii) d'étudier comment les différentes catégories d'associations culturales pratiquées permettent de répondre à des contraintes agronomiques propres à certains terroirs et/ou à certaines exploitations agricoles ; (iii) d'en mesurer l'intérêt économique ainsi que le potentiel pour le développement de systèmes de culture à base de semis direct sous semis direct sous couvert végétal.

Le rythme d'adoption des SCV en petite agriculture, en tant que nouveau paradigme, serarelativement lent et se fera à l'échelle de une ou deux générations. Les effets néfastes duchangement climatique apparaîtront avec un rythme comparable. Raison majeure pouraccélérer la diffusion là où les SCV ont déjà été implantés et pour commencer le plus tôtpossible ailleurs.

Developing and maintaining water control in paddy fields is difficult, costly and requires sufficient water reserves. Thus, even in the main rice growing area of Madagascar, the Alaotra lake region (800 metres above sea level), only 30 000 ha of paddy fields can be properly irrigated when over 70 000 ha will remain under poor water control. In these fields, traditional techniques based on irrigated cropping practices are very unreliable: late transplanting (which can be done only when sufficient water is available) and occurence of dry conditions at the end of the plant cycle lead to usually low yields (0.8 to 1 t/ha on average) and production is very unreliable (from nil, during the dry years to 3t/ha when rains are favourable), which makes crop intensification very hazardous. For such situations, a change in paradigm is proposed: abandoning irrigated practice and making the choice of growing upland or ",poly-aptitude", rice varieties (SEBOTA) with agro-ecological practices adapted to the specific field water regime.

Ce rapport, rédigé après un «survol» très court de 5 jours, des 3 régions pré-sélectionnées, sera volontairement court. Son ambition majeure est de soumettre à l’analyse des Autorités marocaines et de l’AFD, de manière la plus simple, concise et concrète possible : -Des objectifs, -Des stratégies, -Des méthodes d’intervention de la recherche –action participative au service dudéveloppement de l’agro-écologie, -Des moyens spécifiques et des possibilités d’appui scientifique et technique possibles pour démarrer ce projet dans les meilleures conditions possibles.

Cette mission a été réalisée à la demande du directeur général de la Socoma (société cotonnière du Gourma) sur financement DAGRIS dans le cadre des accords CIRAD-DAGRIS. Elle avait 3 objectifs: +Informer les agents de la Socoma et des représentants de paysans sur le SCV. +Conseiller la Socoma sur un dispositif expérimental « léger » à mettre en place pour la saison 2005. + Former plus en profondeur les agents Socoma en charge de ce dispositif.