The use of mulch-based no-tillage is limited in organic cropping systems despite its benefit to soil quality and savings in both labor and fuel. Scientists Vincent-Caboud et al. recently reviewed the production issues of this technique in organic agriculture. They showed that the main problems were cover crop establishment and termination, nutrient management and adequate seed-to-soil contact when planting into thick mulch. More research is needed on cover crops and on developing adequate equipment with farmers’ constraints.
In the context of the European crisis in conventional milk production, many conventional farms are converting to organic farming at the risk of rendering them vulnerable during and after this conversion. In France, scientists Bouttes et al. studied farm ability to respond to technical, climatic and economic effects of such conversion. They showed that conversion to organic farming can be a powerful mechanism for reducing farm vulnerability.
An increasing number of vineyards are converting to organic farming due to concerns about the environmental impacts of agriculture. Change strategies need to be classified to identify the situations requiring the most effort to achieve organic conversion. Scientists Merot et al. classify transition strategies according to a scale of change intensity and speed of changes. This approach improves the understanding of conversion and leads to better support winegrowers during conversion.
Lentil has been overlooked by organic farmers mainly because of low and unstable yields. Scientists Viguier et al. demonstrate that growing lentil in intercrop with low-density spring wheat under organic farming rules provides higher profitability than sole crops, despite additional costs associated with grain sorting.
Peat is the standard substrate used in nursery transplant production although its utilization is cause for environmental and ecological concerns. Scientists Pascual et al. review the new substrate alternatives for organic production. They reckon that compost or other materials supplemented with coir and minerals can bring added values that peat cannot provide, including seedling nutrition, the presence of beneficial microorganisms and pathogen suppression, and allow a more sustainable production.
Olive is a key crop in the Mediterranean basin. Scientists Pleguezuelo et al. analysed the situation of organic farming in Andalusia. They emphasize the need for educational and research programs to promote the demand for these products. They reckon that further support for funding research is essential to characterize the effects of olive cultivation on soils and biodiversity.
Many people highlight the need to increase yields in organic agriculture to provide more organic food for a growing population. Scientists Röös et al. recently reviewed the opportunities and risks of revising the main factors controlling yield in organic agriculture. For example, increased nitrogen inputs carry many risks and few opportunities, whereas the management of ecosystem services provides many risk-free opportunities for improved pest control, thus increasing yields. Organic agriculture needs to reconsider fundamental principles to improve food system sustainability.
What are the convergence and divergence between organic agriculture and agroecology ? Scientists Migliorini and Wezel recently reviewed and compared the principles and practices defined and described in EU organic agriculture regulations, IFOAM norms, and scientific literature in agroecology. They concluded that although these two streams differ on some points, both offer promising contributions for a more sustainable agriculture, especially if their principles and practices transform the agro-food systems.
Organic agriculture seeks to reduce our reliance on non-renewable resources and to affect positively human health. However, its capacity to feed the growing world population is questioned. Scientists Lesur-Dumoulin et al. analysed an extensive dataset of yields from organic vs conventional horticulture and showed that in organic agriculture, yields are on average 10 to 32% lower than in conventional agriculture. Extreme yield reductions (>50%) are very unlikely and there is no evidence that organic agriculture gives more variable yields than conventional one.
Conversion to organic farming is a great challenge in vineyard systems, causing major changes in system structure and management. Agronomists Merot and Wery proposed six complexity indicators to assess modifications to cropping system structure and management during conversion. They demonstrate that conversion to organic viticulture increase the complexity of vineyard structure and management. These indicators can be extended to all agricultural systems to diagnose the impact of organic farming conversion.