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International audience; Since the 1970s, winter wheat management in France has focused on growing high-yielding cultivars with the intensive use of external inputs. However, over the last 10 years, breeding priorities have changed in favour of the development of cultivars with multiple resistance to fungal diseases and lodging. Low-input strategies have also been developed, to reduce costs and to meet environmental targets. In this study, we assessed the economic, energetic and environmental performances of three cultivars (C) grown under four management intensities. Two of these cultivars (Isengrain and Tremie) are both high-yielding and disease-susceptible, whereas the third (Oratorio) is multiresistant to diseases and lodging but has a lower potential yield. The four crop management systems (CM) were designed with a decrease in input level (seeds, N fertilizer, fungicides, growth regulator) from CM1 to CM4. We set up a multi-year ant multi-site network to test the C-CM pairs in a wide range of environments. The evaluation of C-CM pairs was based on a set of indicators dealing with economics (profitability, input and machinery costs per tonne), environment (pesticide use, N recovery), and energy (energy use efficiency, energy costs). As regards profitability and costs per tonne, we assessed the vulnerability of the C-CM pairs to several grain and oil price scenarios. The demonstration of synergy between the two types of innovation (multiresistant cultivars, low-input management) is a major result: each makes the other more profitable, increasing its chances of adoption in the field. The ecology-based technology package, involving the use of lower-yielding multiresistant cultivars under lower external input levels, was more profitable when grain prices were low (less than (sic)123-157 per tonne (for low and high oil prices, respectively)). By contrast, the intensive technology package, consisting of high-yielding cultivars and high levels of external inputs (N, fungicides and growth regulators), was more profitable when grain prices exceeded (sic)123-157 per tonne (for low and high oil prices, respectively). However, it was less optimal in terms of fossil energy use and potential on environmental impact. In a context of fluctuating grain and oil prices and a need to preserve resources (e.g. fossil energy, water quality), our results demonstrate the potential benefits of using low-input crop management systems. with cultivars displaying multiple resistance to diseases and lodging (Oratorio-CM3). The loss of productivity (1 t ha(-1) less than for Isengrain-CM2) due to the lower yield potential of the multiresistant cultivar and the lower levels of inputs must be seen as a necessary evil if we are to decrease the overuse of resources. There is a need to adapt current procedures for cultivar evaluation, to promote the breeding of multiresistant cultivars for low-input systems. New cultivars should be evaluated under a range of conditions, from high- to low-input systems. (C) 2011 Elsevier B.V. All rights reserved.

The breeding of winter wheat (Triticum aestivum L.) for resistance to major fungal diseases has been a priority over the last 15 years in France. During this period, integrated low-input strategies have been developed for winter wheat, to cope with falling grain prices and growing environmental concerns. We investigated the interactions between genotype and management for disease and lodging intensities, and analysed their effects on yield within an integrated crop management (CM) context. A multi-environment experimental network (13 locations, studied in three seasons, between 1999-2000 and 2001-2002) comprising several combinations of cultivars and CM systems was carried out. Four rule-based CM plans were defined, with a decrease in input level from CM1 (a high-input CM plan designed to maximise the yield of a given cultivar) to CM4 (a low-input system with no fungicide protection, no plant growth regulator applications, a sowing density 40% lower than for CM1, and 90 kg ha−1 less N fertiliser than for CM1). Cultivars were clustered into three groups (cultivar type (CT) CT1-CT3), according to their scores for resistance to diseases, for the analysis of yield, whereas the resistance cultivar rating (CR) for each disease and for lodging was considered for the analysis of disease and lodging intensities. For all diseases, CM had a significant effect (P