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The integrated approach of weed management refers to a combination of direct and indirect methods in order to limit chemical applications. In oilseed rape, sunflower and soybean, mechanical weed control can be an alternative or a complement to herbicides and should take progressively a larger place in the direct weed control options, taking into account of the policy of restriction of chemical use. CETIOM launched a research program to assess, in different backgrounds, the selectivity and the efficacy of three tools, used either alone or combined with herbicides: the rotary hoe, the finger weeder and the in-row hoe. As an alternative or a complement to herbicides, mechanical weed control strategies were selective enough for oil crops if they were used in appropriate conditions (crop stage, soil surface moisture, adjustments of the tools). Linked with long term preventive measures to maintain weed population at a low level, they could be as efficient as herbicides but with an irregularity and strongly dependent on weed development stage. These techniques could be economically competitive but require often more working time. Mechanical management can thus be an answer to some of the new requirements of the agricultural context but operator skill, experience and knowledge are critical to success. Introducing these weed control methods in a farm requires a deep change of state of mind which appears today as a major restraint for the farmers.

INRA has initiated a comprehensive approach to food loss and waste for all the plant and animal sectors, from field to distribution. In this study, all comestibles that leave the human food chain and are not recycled into animal feed are considered as losses and waste. The main French oilseed sectors are studied (rapeseed, sunflower and soya, as well as tofu). In order to identify the key sources of loss, all of the various steps in the process of the oleaginous production chain are described, from harvesting through to distribution, including storage, transport, crushing, refining and packaging. For tofu, the study also examines the chain from harvest through to distribution, including as soy milk and tofu paste. Published data are lacking; they were therefore primarily collected directly from professionals in the sectors concerned. Although oilseeds and vegetable oils are apt to have a relatively long shelf-life compared to other products, losses of vegetable oil from field to distribution are substantial (approximately 71.4 kT, equivalent to 10% of the amount consumed in France). We establish that the principal steps giving rise to losses are harvesting and refining. Total losses in French rapeseed oil, sunflower and soybean were estimated at 9.8%, 7.0% and 6.0% of their respective total potential production, worth approximately 50.6, 14.3 and 6.5 € million and equivalent to the annual consumption of approximately 3 030 000, 855 000 and 390 000 people. In the case of tofu, harvest is the most important area of loss. Total losses of tofu are equivalent to 8.2% of potential production. We discuss potential measures to improve the efficiency of the individual steps of French oilseed production.

Oilseed rape seed loss during harvest can cause subsequent unwanted gene flow and thus give raise to management difficulties in order to keep segmented different productions. Furthermore, seed loss reduces benefits of producers. This loss was evaluated in different conditions and trials carried out in three French regions from 2002 to 2004. Seed loss was divided into three categories : before harvest, under the cutter bar and behind the combine harvester. Total loss represented on average 8,2 % of the harvest for grain water content under 12 %. But this figure does not take an important variability into account. Indeed, an advanced cutter bar could reduce loss by 80 % and grain humidity at harvest plays an important part in the total loss level and its distribution. Before harvest low grain water content could make seed loss more sensitive to climatic events. Under the cutter bar, seed loss is inversely proportional to grain water content. On the contrary, it increases with grain water content behind the combine, due to loss in green siliquae. These studies can help improving advice to producers and contribute to improve gene flow models.