The use of multi-resistant cultivars allows a significant reduction in fungicide use in low-input cropping systems. However, many major wheat cultivars used in Europe remain sensitive to frequent diseases and require fungicide protection. This paper aims at understanding the factors explaining the low level of adoption of multi-resistant wheat cultivars in Wallonia (Belgium). Cultivar adoption has been an important topic of research, but few analyses have been done in Europe in the past decades. We used a systems approach combining a survey among stakeholders in the food chain and a systematic analysis of the publications of extension services. We identified twelve factors impeding wider adoption of multi-resistant cultivars. These factors explain why current wheat-cropping systems are maintained in a 'pesticide lock-in' situation, an economic concept that could be used more frequently to study agricultural innovations. Considering these intangible 'barriers' to current and forthcoming innovations is a first step towards a more comprehensive policy to promote sustainable agriculture. Similarities between Wallonia and France are discussed and methods of promoting wide use of resistant cultivars are proposed.