Evolution and challenges of varietal improvement strategies

Agricultural production and supply chains are facing major challenges in the form of increasing demand for food products, a diversified use of agricultural products including for non-food purposes, ecologically intensive agriculture, and the necessity of taking climate change into account. The creation and adoption of new varieties that are productive, diversified, better adapted, and more environmentally friendly can help cropping systems that seek to address these issues become more efficient. Plant breeding efforts must anticipate the needs of the end users and adapt to very different agri-chains, illustrated in this chapter by two examples: first, an agri-chain that is highly structured around targeted export products, for example, the dessert banana, which requires ideotypes that meet the requirements of production and marketing systems; and second, an emerging agri-chain for multi-use sorghum, characterized by new production objectives of increased energy potential and production of biomaterials, sometimes without compromising with the requirement of high grain yields. To meet the objectives and the sustainability of agri-chains, research into genetic improvement must propose new approaches, new tools, and innovative breeding methods. The objectives, and sometimes the entire breeding process, are shared with all the actors, especially the end users, as part of an enhanced partnership within agri-chains. The breeding strategy also depends on ease of access, better use of available and useful genetic resources, in-depth knowledge of the structure and diversity of these resources, genetic determinism of desirable traits, and pre-breeding approaches. All these scientific and partnership innovations ensure the necessary responsiveness to support the execution of current breeding processes and the identification of new varieties that meet current and future uses and services. (Résumé d'auteur