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During a complex investigation programme on the evaluation of the long‐term ecological impact of cropping Miscanthus, the substrate composition of residues in 4–8‐year‐old stands of Miscanthus × giganteus and the contribution of Miscanthus residues to soil organic matter (SOM) were investigated. Only about 50 % of the above‐ground biomass produced yearly was suitable for harvest because of pre‐harvest losses and harvesting residues. The potential supply to SOM was therefore 3.1 t ha−1 carbon annually accumulated by the litter, and 9.1 t ha−1 carbon accumulated by rhizomes and roots in the long term. These organic residues mineralized differently in laboratory experiments at generally high rates of decomposition. Analysis of soluble portions of the organic substance of these biomass components by hydrolysis with hot water, 2 % HCl and 80 % H2SO4 confirmed the results. Setting the SOM effect of an equivalent farmyard‐manure (FYM) supply to 100 %, Miscanthus residues reached 60 % (stubble, rhizomes), 80–90 % (pre‐harvest losses) and 100 % (roots). Established Miscanthus stands are able to produce about 8.2 t ha−1 organic substance, which is comparable with FYM in terms of SOM impact. This kind of calculation showed higher values for Miscanthus than for the agricultural crops investigated to date. An SOM increase of about 0.5 % on sandy soils and 0.2 % on silt soil was determined after 6–8 years of cropping Miscanthus × giganteus.

Using the advanced backcross quantitative trait loci (AB-QTL) strategy, we successfully transferred and mapped valuable allelic variants from the high b-glucan (BG) accession IAH611 (PI 502955), into the genome of cultivar 'Iltis'. By backcrossing one BC 1 F 1 plant to 'Iltis', we developed two BC 2 F 2-6 populations A and B, comprising 98 and 72 F 2 -individuals, respectively. Genotyping of BC 2 F 2 individuals with predominantly AFLP markers resulted in 12 linkage groups with a map size of 455.4 cM for Population A and 11 linkage groups with a map size of 313.5 cM for Population B. Both populations were grown at three sites in Germany over a three-year period. Individuals were then phenotyped for 13 traits including grain yield (YD) and b-glucan content (BG). QTL analysis via stepwise regression detected a total of 33 QTLs, most of which were clustered in three linkage groups. Two dense linkage groups A1 and B13 were found to be putatively homologous to groups KO_6 and KO_11 of the 'Kanota'/'Ogle' map, respectively. Materials and MethodsPlant materials and trait assessment: The development of two AB-QTL populations was initiated by evaluating and identifying parents with high b-glucan content for a crossing programme. Two accessions, known to have high b-glucan content, IAH611-447 (PI 502955), abbreviated IAH611 and PA8290-5869 (Tables S1 and S3) obtained Plant Breeding, 133, 588-601 (2014)

Over the last three decades, Fusarium infections and related mycotoxin contamination have caused significant economic losses in oats (Avena sativa L.). Breeding for resistance is highly prioritized in oats, but infection processes and resistance components against Fusarium species are not fully identified. In this study, the genetic variation for flowering traits and its impact on mycotoxin accumulation in oats is described. The first experiment of this paper was focused on flowering traits in 50 oat genotypes (Panel 1) to identify cleistogamic oats. Then, two separate Fusarium-inoculated experiments in three (Panel 2 with 25 genotypes) and two environments (Panel 3 with 16 genotypes) were conducted to assess the relationship between the degree of anther retention (AR) and resistance to Fusarium infestation and mycotoxin accumulation in oats. Panel 2 was inoculated with Fusarium culmorum, F. langsethiae, and F. sporotrichioides, and Panel 3 was inoculated with either F. graminearum or F. culmorum. The assessment of open flowering score and AR displayed a continuous variation from dominating chasmogamy to complete cleistogamy. Significant differences for deoxynivalenol and T-2 were found, with a modest correlation between both mycotoxins. The lowest mycotoxin levels were found in two old and one modern cultivar, and the highest levels were found in a dwarf oat cultivar.

The breadmaking potential of six oat varieties was compared with and related to their physicochemical properties. The most significant differences in the bread characteristics were found in the crumb structure. The varieties Buggy, Energie, and Zorro resulted in good bread quality with an even gas‐cell distribution characterized by a high number of relatively small pores. In contrast, Typhon, Ivory, and Nord 08/311 each had a large hole in the center of the crumb and accordingly poor quality. Breads differed little in specific volume, bake loss, and density. Rheological analysis revealed positive effects of low batter resistance to deformation on oat bread quality. On the basis of the physicochemical characterization, protein and fat contents were identified as key factors responsible for differences observed in bread quality, provided that starch damage and water‐hydration capacity were low. Additionally, high setback and final viscosity, as determined by Rapid Visco Analyser (RVA) analysis, positively affected oat bread quality. High α‐amylase activity was found to influence negatively the breadmaking performance of oats. Overall, protein, fat, dietary fiber content, starch pasting properties, and α‐amylase activity were responsible for the breadmaking properties of oat varieties.