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The effects of living mulch (LM) introduction and management strategies on cash crop yield, product quality and energy use were studied in a wide range of European vegetable cropping systems, climatic and soil conditions, as well as species of LM grown as agro-ecological service crops. Nine field experiments were carried out in research stations and commercial farms located in Denmark, Germany, Italy and Slovenia. Farmers’ perception of the feasibility and applicability of the LM technique was also assessed.The results demonstrated that the LM systems with a substitutive design can be effectively implemented in vegetable production if the value of the ecological services (positive externalities) delivered by LM can counterbalance the yield loss due to the cash crop density reduction. The crop density of the system and the length of the period in which the LM and cash crop coexist are oppositely related both for competition and yield. Moreover, if an additive design is used, the LM should be sown several weeks after the cash crop planting. Overall, different cash crop genotypes (i.e., open pollinated/local cultivars in comparison with the hybrids) performed similarly. Use of human labor (HL) and fossil fuel (FF) energy slightly increased in LM systems (7%), and there was a shift in the proportion of FF and human energy consumption. The farmers’ acceptance of the LM techniques was quite high (75% of the interviewed sample), even though their critical considerations about yield quality and quantity need consideration in future research and practical implementation of LM systems.

International audience; The development of sustainable cropping systems is a key priority for agronomists and crop scientists. A first step involves understanding the relationship between cropping system performance and farmers’ practices. To complete this step, a methodological framework entitled Regional Agronomic Diagnosis (RAD) has been developed. During the last ten years, the scope of the regional agronomic diagnosis has been enlarged to include several factors describing crop quality and the environmental impact of cropping systems. Regional agronomic diagnosis has led to several major advances such as (1) the assessment of the effect of preceding crop and soil structure on malting barley quality in France and (2) the assessment of the effects of ploughing, nematicide use and fertilisers on soil properties in intensive banana plantations in the West Indies. Improvements have also been gained in methodology, particularly by the selection of indicators for assessing the effects of crop management, soil and weather conditions, and data analysis. Finally, regional agronomic diagnosis has been integrated into more general approaches of agricultural development. We review here this methodological progress.

Identifying the appropriate germplasm to be improved is a key component of any participatory breeding effort because of its implications for impacts on social welfare and genetic diversity. This paper describes a method developed to select a subset of 17 populations for a participatory breeding project from a set of 152 maize landraces. The larger set of landraces was collected in order to characterize, for conservation purposes, the maize diversity present in the Central Valleys of Oaxaca, Mexico. The method combines data representing the perspectives of both men and women members of farm households and those of genetic resources specialists, including professional plant breeders, gene bank managers, and social scientists. The different perspectives complement each other. The results show that when the choice of germplasm is based only on the perspective of genetic resources specialists, traits and materials that are important to farm households may be ignored. Such selections may be less valuable to farmers, limiting the impact of the participatory breeding effort on their livelihoods. However, the findings also indicate that relying solely on the perspectives of farm households may lead to lower diversity. Choosing populations based solely on either perspective involves a social cost-either in terms of diversity or in terms of farmer welfare. Although our approach has limitations, many of which are common to participatory research, it represents a systematic method for meeting one of the important challenges of participatory plant breeding.