The need for increased sustainability of performance in cereal varieties, particularly in organic agriculture (OA), is limited by the lack of varieties adapted to organic conditions. Here, the needs for breeding are reviewed in the context of three major marketing types, global, regional, local, in European OA. Currently, the effort is determined, partly, by the outcomes from trials that compare varieties under OA and CA (conventional agriculture) conditions. The differences are sufficiently large and important to warrant an increase in appropriate breeding. The wide range of environments within OA and between years, underlines the need to try to select for specific adaptation in target environments. The difficulty of doing so can be helped by decentralised breeding with farmer participation and the use of crops buffered by variety mixtures or populations. Varieties for OA need efficient nutrient uptake and use and weed competition. These and other characters need to be considered in relation to the OA cropping system over the whole rotation. Positive interactions are needed, such as early crop vigour for nutrient uptake, weed

Modern agriculture and conventional breeding and the liberal use of high inputs has resulted in the loss of genetic diversity and the stagnation of yields in cereals in less favourable areas. Increasingly landraces are being replaced by modern cultivars which are less resilient to pests, diseases and abiotic stresses and thereby losing a valuable source of germplasm for meeting the future needs of sustainable agriculture in the context of climate change. Where landraces persist there is concern that their potential is not fully realised. Much effort has gone into collecting, organising, studying and analysing landraces recently and we review the current status and potential for their improved deployment and exploitation, and incorporation of their positive qualities into new cultivars or populations for more sustainable agricultural production. In particular their potential as sources of novel disease and abiotic stress resistance genes or combination of genes if deployed appropriately, of phytonutrients accompanied with optimal micronutrient concentrations which can help alleviate aging-related and chronic diseases, and of nutrient use efficiency traits. We discuss the place of landraces in the origin of modern cereal crops and breeding of elite cereal cultivars, the importance of on-farm and ex situ diversity conservation; how modern genotyping approaches can help both conservation and exploitation; the importance of different phenotyping approaches; and whether legal issues associated with landrace marketing and utilisation need addressing. In this review of the current status and prospects for landraces of cereals in the context of sustainable agriculture, the major points are the following: (1) Landraces have very rich and complex ancestry representing variation in response to many diverse stresses and are vast resources for the development of future crops deriving many sustainable traits from their heritage. (2) There are many germplasm collections of landraces of the major cereals worldwide exhibiting much variation in valuable morphological, agronomic and biochemical traits. The germplasm has been characterised to variable degrees and in many different ways including molecular markers which can assist selection. (3) Much of this germplasm is being maintained both in long-term storage and on farm where it continues to evolve, both of which have their merits and problems. There is much concern about loss of variation, identification, description and accessibility of accessions despite international strategies for addressing these issues. (4) Developments in genotyping technologies are making the variation available in landraces ever more accessible. However, high quality, extensive and detailed, relevant and appropriate phenotyping needs to be associated with the genotyping to enable it to be exploited successfully. We also need to understand the complexity of the genetics of these desirable traits in

Differences among six winter wheat varieties regarding N efficiency (NE) and its components were assessed in field trials in four locations over 3 years under conditions of organic farming (OF). N uptake and utilization efficiency, redistribution of N vs. direct N uptake during grain filling, N uptake in three periods (tillering, stem elongation/heading and grain filling) and the quantity of mineralized N during the same sub-periods were determined. Significant differences for these traits and significant interactions among varieties and environments could be detected for NE and its components. Limiting N availability during grain filling was typical for the more extensive organic environments. Under these conditions, differences of NE could be attributed to differences in preanthesis uptake and in translocation from vegetative tissues to the developing grain. Pre-anthesis uptake contributed more to N efficiency than translocation efficiency. Under more favourable conditions, differences became more evident and were mainly due to direct uptake during grain filling. This confirms, that different varieties are necessary in different environments and that breeding may contribute to improve baking quality to a certain extent. However, utilization of mineralized N is still unsatisfactory in OF systems in Germany. More N efficient varieties alone will help only little to resolve this problem; this can be achieved only by also improving the cropping systems.

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The temperature of leaves and canopies of plants has long been recognised to be an indicator of plant water stress and can be assessed by thermometry or thermography. Considerable research has been carried out with each of these techniques individually; however, a comparable assessment has not been done to the best of our knowledge. Therefore, we compared the potential of high‐resolution thermography and infrared (IR) thermometry to discriminate among stress treatments (control, drought, salt and combined salt and drought) and cultivar effects in large container‐based experiments that mimicked field conditions. Differences among treatments and between cultivars, with differences varying between 1–9 and 0–2 °C, respectively, were in dense crop stands comparably well ascertained by IR thermometry and thermography. Both methods allowed discriminating differences in salt tolerance. Interestingly, enough similar results were observed for processed, by unmixing the soil influence, and unprocessed thermal images at soil coverage higher than 60 %. Using thermography and IR thermometry, highly significant and close relationships were established between canopy temperature and leaf water potential. Overall, in this study, the more simplistic technique based on IR thermometry performed in dense crop stands similarly well as the more sophisticated method provided by thermography.