Enhanced productivities on farmers’ fields, with minimal ecological footprints, is a sustainable means for addressing the myriad constraints that threaten the 21st century global food security. Clearly, a diverse set of hardy, high yielding and input use-efficient crop varieties will, along with ecosystem-based agronomic practices, constitute the crop production packages needed to nourish an ever increasing human population, meet the demands of other industries for food-based substrates and yet leave the environment largely unharmed. The currently available cultivars of most staple crops do not fit into this envisaged highly efficient yet low-input crop production systems. This implies that a new portfolio of crop varieties will need to be bred.