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Key message A novel approach based on the loaf volume–grain protein content relation is suggested to consider the static protein use efficiency and stability as efficient quality-related descriptors for wheat varieties. Abstract The most important trait for baking quality of winter wheat is loaf volume (V). It is mostly determined by grain protein content (GPC) and quality. New varieties with a high potential of grain protein use efficiency (ProtUE) are very important for reducing the surplus use of nitrogen fertilizer in areas where nitrogen leaching is large. This is also an important goal of agricultural policies in the European Union. Additionally, ProtUE needs to be very stable across environments in the face of progressing climate change with more volatile growing conditions. We evaluated a new approach to assess ProtUE and stability based on the V–GPC relationship instead of using only single traits. The study comprised 11,775 baking tests from 355 varieties grown 1988–2019 in 668 different environments in Germany. V was predicted by quadratic and linear regression functions for quality groups, indicating a reduction of ProtUE from 1988 to 2019. We introduced a dynamic and a static approach to assess ProtUE and stability as potential criteria in variety registration. We found a considerably lower heritability of the dynamic ProtUE (h2 = 43%) compared to the static ProtUE (h2 = 92%) and a lower dynamic stability (h2 = 32%) than for the static stability (h2 = 51%). None of these measures is in conflict with the selection for high V. In particular, V and static ProtUE are strongly genetically associated (r = 0.81), indicating an advantage of the static over the dynamic approach.

The determination of loaf volume (LV) in winter wheat by the rapid mixed test (RMT) is laborious and expensive. In Germany LV of wheat samples from a national harvest survey is predicted routinely by a linear regression equation introduced by Bolling in 1969 with predictor variables protein concentration (PC) and sedimentation value (SV). Breeding progress generated varieties with improved quality so that the predictive power of the Bolling's equations, which were updated, decreased steadily. The objective of this study is to evaluate linear regression models based on PC and SV with improved accuracy using data from mill samples and from official variety trials (VCU) including varieties with quality ratings A, E and B. As criterion for the prediction accuracy we used the root mean squared deviations sMSD of observed and predicted LV. Two basic regression models were used across quality groups and group-wise fashion. The average prediction accuracy of Bolling's equations (sMSD = 77.0) was considerably lower than the derived regression options (41.5

International audience; Technological (processing performance and end-product) and nutritional quality of wheat is in principle determined by a number of compounds within the wheat grain, including proteins, polysaccharides, lipids, minerals, heavy metals, vitamins and phytochemicals, effecting these characters. The genotype and environment is of similar importance for the determination of the content and composition of these compounds. Furthermore, the interaction between genotypes and the cultivation environment may play a significant role. Many studies have evaluated whether the genotype or the environment plays the major role in determining the content of the mentioned compounds. An overall conclusion of these studies is that except for compounds encoded by single major genes, importance of certain factors mainly depend on how wide environments and how diverse cultivars are within these comparative studies. Comparing environments all over, e.g. across Latin America, ends up with a high significance of the environment while large studies including genotypes of wide genetic background result in a significant role for the genotype. In addition, for some technological properties and components, genotype has a higher effect (e.g. grain hardness and gluten proteins), while environment influences stronger on others (e.g. protein and mineral content).Content and concentration of proteins, but also to some extent of starch, some non-starch polysaccharides and lipids, are essential in determining the technological quality of a wheat flour. For nutritional quality of the flour, the majority of the compounds are together the important determinant. Thus an increased understanding of environmental effects is essential. As to how the environment is influencing the content of the compounds, there are some differences. The protein content and composition is strongly affected by environmental factors influencing nitrogen availability and cultivar development time. However, these two factors are impacted by a range of environmental (temperature, precipitation, humidity/sun hours, etc.) and agronomic (soil properties, crop management practices such as seeding density, nitrogen fertilizer application timing and amount, etc.) components. Thus, to understand the interplay between the various environmental and agronomic factors impacting the technological quality of a wheat flour, modeling is a useful tool. Several other compounds, including minerals and heavy metals, are to a higher extent determined by site specific variation, resulting in similar rankings of entries across locations, although the total content is varying among years. The bioactive compounds and vitamins are a part of the defense mechanisms of plants and thus there is a variation in these compounds depending on prevailing biotic and abiotic stresses (heat, drought, excess rainfall, nutrition, diseases and pests). Thus, even for nutritional quality of wheat, incorporating all compounds of relevance in the evaluation would benefit from modeling tools.

Grain characteristics (hardness, protein content/quality, starch properties, enzymatic activity, etc.) play an important role in the definition of end use quality for wheat-based products. Among them, gluten strength and extensibility, mostly determined by glutenin and gliadin composition, are two of the main factors that determine gluten quality. The complex inheritance of most quality traits has led to the development of indirect tests used in breeding for early and advanced generation selection. The main focus of breeders is adding resistance to biotic stress (fungi, insects, nematodes, etc.) and increasing grain yield while selection for quality often occurs in later generations. This often results in the propagation of poor quality lines that must be later discarded. Evaluation of quality in early generations requires suitable tests, preferably non-destructive. Increasing knowledge of the genes involved in quality will facilitate more precise and effective selection. Recent advances in wheat genome sequencing and the extensive genotyping of mapping populations has led to a precise molecular characterization of high molecular weight (HMW) and low molecular weight (LMW) glutenins, as well as the discovery of genes associated with quality traits like grain hardness, starch composition (e.g., waxy genes), etc. Massive genomic data will impact in breeding programs allowing quality fine tuning by precise selection of glutenins, starch, hardness and other traits, for specific end uses through marker assisted selection, genomic selection, etc. This chapter will describe different methods used for quality selection in breeding programs and research, and some examples of integration of local breeding programs with the extremely diverse end-uses of wheat based on a series of case-studies. Current and potential approaches to quality evaluation in durum wheat, wild relatives and synthetic wheat breeding programs will be also presented.

New strategies for a reliable assessment of baking quality of wheat are required since the protein content is a widely discussed indicator in this respect. In this study, the indicator value of the protein content for baking quality was evaluated using almost 600 wheat samples representing different quality and varieties. NIRS calibrations were developed to estimate bread volume at different levels of processing. Bread volume increased with increasing protein content in a wide curvilinear relationship with an R 2 of 0.59. At protein contents above 12% representing the relevant range for trading, the R 2 dropped to 0.15. Different wheat varieties showed differential responses (i.e. linear and non-linear) in bread volume to increasing protein content. The performance of NIRS calibrations for bread volume were best at the processing level of dough (R 2 0.81) and good at the level of whole grains (R 2 0.70). Hence, the protein content is not a reliable indicator for baking quality on its own. Bread volume was predicted better by NIRS calibrations than by protein content. A strategy is presented paying attention to the variety specific interplay between baking quality and protein content with implications for the variety registration system, trading, breeding and nitrogen fertilisation.

The GlutoPeak ® -Test (GPT) as a rapid small-scale technique was optimized to evaluate the gluten aggregation properties and to predict the loaf volume, on the basis of a multiyear and multilocation analysis of wheat samples, using different solvents. 5 % lactic acid and 1 % sodium chloride displayed significant GPT responses. Relationships between protein content, sedimentation value, GPT parameters and loaf volume were investigated. With 1 % sodium chloride, the torque 15 s before maximum torque (AM) presented the highest correlation with loaf volume of samples from 2013 to 2014 (r = 0.77, r = 0.63, p

In addition to or as substitution for a regulated isolation distance, conventional maize (Zea mays L.) border rows at the genetically modified (GM) maize field edge are considered as feasible measure to ensure coexistence between GM and conventional or organic maize. Therefore, we examined the effectiveness of 9-m-and 18-m-wide non-GM maize borders at the GM maize field edge on outcrossing rates into a neighboring non-GM maize field. One field experiment each was conducted in 2008 at three sites in Germany using a field orientation representing a worst-case scenario concerning wind direction. In each case, the distance between GM and non-GM maize fields was 51 m. At two sites, sizes of GM and non-GM maize fields were 0.8 ha, respectively, and at the third site 0.5 ha (GM) and 0.3 ha (non-GM). The GM percentages of individual samples taken at recipient field depths between 0 and 90 m were quantified by real-time polymerase chain reaction. Overall, no pollen-mediated gene flow reducing effect of border rows was observed in the present study, although synchrony of anthesis between GM maize and border row maize was given at each site. Calculated GM contents of the total non-GM fields harvest were always below the European Union labeling threshold of 0.9%. In consequence, planting 9-m- or 18-m-wide conventional maize border rows at the GM field edge is no reliable coexistence measure, at least if combined with an isolation distance.

Recently, the introduction of GM maize in agricultural production in the EU and elsewhere has raised the issue of adventitious presence of GM seeds in conventional seed lots. Adventitious presence may occur in all arable farming, and at any step in the production of seeds or grain, or in processing of harvested product in the food/feed chain. As of today, there are no official thresholds governing the adventitious presence of GM seeds in conventional seed lots in Europe. However, it is assumed that GM admixture in seed lots could have a considerable influence on the level of adventitious presence in the non-GM harvested product. The experiments highlighted in this paper aim at the consequences of adventitious presence of GM maize seeds in conventional seed lots. It is shown for varieties belonging to the same maturity group that the final GM rate (% seeds) in the harvest product is nearly same as the initial seed admixture (% seeds). This corresponds to Hardy–Weinberg expectations. The variation depends mainly on the flowering coincidence, the site and climatic conditions. In cases where the admixed seeds are of different maturity group, the level of cross-pollination in the harvest product is reduced. Furthermore a comparison between the visual GM seed detection and real-time PCR detection was done. It is evident that the result of the real-time PCR detection method has a more variable uncertainty associated with its results than the visual seed testing method. The accuracy of prediction from % GM seed to % GM DNA depends on the reference material used for calibration curves.

With 3 figures and 4 tables Abstract At the field scale, pollen flow between adjacent fields limits the potential of coexistence of different farming production systems, especially for allogamous crops like oilseed rape whose pollen is disseminated by insects or wind. In this article, we examine the efficiency of cleistogamy in an oilseed rape line which showed between 90% and 99% of flowers closed at flowering, in limiting deposition of allo-pollen. Five trials were established, consisting of two adjacent blocks, the one sown with the cleistogamous low-erucic acid line and the other with a classically flowering high-erucic acid line, used as source of contaminating pollen, itself artificially contaminated with a 1% mix of cleistogamous plants. Analyses showed that cross-fertilization rates of cleistogamous plants, estimated through erucic acid contents of seeds collected from them, were lower than those generally observed in oilseed rape: it averaged 10.1% on isolated plants within the erucic blocks, reached to the maximum 14% immediately adjacent to the erucic block, then decreased exponentially at higher distances. Cleistogamy appeared therefore as one imperfect means of gene bio-containment.

The most reliable and practicable measure in assuring coexistence in respect to pollenmediated gene fl ow from genetically modifi ed (GM) to conventional maize (Zea mays L.) is an isolation distance separating GM and non-GM fi elds. Therefore, we tested distances between 24 and 102 m at three sites in northern Germany using a fi eld orientation representing a worst case scenario concerning wind direction. During the 3 yr of fi eld trials the highest levels of gene fl ow occurred at the site and year with the longest fl owering synchrony and the strongest wind blowing constantly from the GM to the non-GM fi eld. It was shown that the GM content of a neighboring non-GM maize fi eld is mainly determined by wind speed and direction as well as by non-GM maize fi eld depth. Based on the maximum outcrossing data obtained it can be concluded that for non-GM maize fi elds being 200 m deep or more an isolation distance of 50 m is suffi cient to keep the GM content of the total fi elds grain harvest below the European Union (EU) labeling threshold of 0.9%. However, non-GM grain maize fi elds with smaller fi eld depth require larger isolation distances or additional coexistence measures. In most cases discarding 6 m of the GM maize facing non-GM maize fi eld edge has proven to be such a valuable measure. In silage maize production 50 m isolation distance is adequate even for non-GM maize fi eld depths down to 50 m. We recommend fl exible separation distances in dependence on non-GM maize fi eld depth to comply with EU coexistence requirements.

Maize (Zea mays L.) Plus-Hybrids are a blend of cytoplasmic male-sterile (CMS) hybrids and unrelated male-fertile hybrids ensuring pollination of the whole stand. Combining potential benefits of male sterility (CMS effect) and allopollination (xenia effect), they often outperform the corresponding male-fertile sib-pollinated hybrids in terms of yield. The combining abilities of five CMS hybrids and eight pollinators were investigated in a factorial split-plot design in 12 environments in four countries and two years. The plant material from different breeders represented the three types of male-sterile cytoplasm. Plus-Hybrids increased grain yield, on average, by 10% or more and by up to 20% in specific environments. Three highly responsive CMS hybrids and four generally good pollinators were identified. The Plus-Hybrid effect affected both yield components, CMS leading mainly to a higher number of kernels (KN) and the xenia effect mainly to an increase in the thousand kernel weight (TKW). Despite some differences in the response of the three types of CMS, the effect of the cytoplasm was not significant. While the CMS effect depended strongly on environment, the xenia was consistent in all environments but its extent varied. As well as increasing yield, we can expect that Plus-Hybrids can make a large contribution to the coexistence of transgenic and conventional maize by biocontainment, that is, eliminating or reducing the release of transgenic pollen in Bacillus thuringiensis (Bt) maize or herbicide-tolerant (HT) maize.

Several biological containment methods have been developed to reduce pollen dispersal; many of them only have a proof of concept in a model plant species. This review focuses on biological containment measures which were tested for their long-term efficiency at the greenhouse or field scale level, i.e. plastid transformation, transgene excission, cleistogamy and cytoplasmic male sterility (CMS). Pollen-mediated gene transfer in transplastomic tobacco could occur at very low frequencies if the predominant mode of inheritance is maternal. Transgene excision from tobacco pollen can be made highly efficient by coexpression of two recombinases. For cleistogamous oilseed rape it was shown that some flowers were partially open depending on genotypes, environment and recording dates. Reports on the stability of CMS in maize and sunflower indicated that there is a high variability for different genotypes under different environmental conditions and over successive years. But for both crop types some stable lines could be selected. These data demonstrate that the biological containment methods discussed are very promising for reducing gene flow but that no single containment strategy provides 100% reduction. However, the necessary efficiency of biological containment methods depends on the level of containment required. The containment level may need to be higher for safety purposes (e.g. production of special plant-made pharmaceuticals), while much lower containment levels may already be sufficient to reach coexistence goals. It is concluded that where pollen-mediated gene flow must be prevented altogether, combinations of complementary containment systems will be required.

Cytoplasmic male sterility (CMS) is a maternally transmitted trait, whereby a plant is unable to produce viable pollen. Studies have revealed that this trait is a tool for enabling effi cient and reliable coexistence between genetically modified (GM) and non-GM cultivation by biocontainment of GM maize (Zea mays L.) pollen. Maize has three types of male-sterile cytoplasm (T, S, and C), the fertility of which can be restored by nuclear rf genes or by interactions with the environment. Twenty-two CMS versions of modern European maize hybrids were evaluated in 17 environments in Switzerland, France, and Bulgaria, with two or three sowing dates, in 2005 and 2006. Stable and unstable male sterility occurred in all three CMS types. T-cytoplasm hybrids were the most stable, while S-cytoplasm hybrids often showed partial restoration of fertility. C-cytoplasm was similar to T-cytoplasm with regard to maintaining male sterility. Climatic factors, especially air temperature, evapotranspiration, and water vapor, during the 10 d before anthesis as well as during anthesis, were correlated positively or negatively with the partial reversion to male fertility of CMS hybrids, indicating an interaction between genetic and climatic factors. This study illustrates that T- and C-cytoplasm in particular open up viable prospects for containing transgenic pollen, especially for Bt-maize.

One approach to ensuring coexistence of genetically modified (GM) and conventional maize (Zea mays L.) is reducing pollen-mediated gene flow. Field experiments were conducted in 2005 at four sites in Germany to compare a tall sunflower crop (Helianthus annuus L.) vs. a short clover-grass crop (Trifolium pratense L. and Lolium spp.) with regard to their ability to reduce outcrossing when grown as buffer between pollen donor and recipient maize plots. Three different maize test systems were used: (i) quantification of a donor transgene via real-time polymerase chain reaction (rt PCR), (ii) a nontransgenic test system based on a dominant kernel color trait, and (iii) a molecular marker test system based on rt PCR quantification of a cultivar-specific nontransgenic DNA sequence. We found that the three test systems yielded comparable results concerning buffer-crop effectiveness and edge effects. There was no difference in outcrossing rates when comparing the sunflower vs. clover-grass buffer crop. Outcrossing rates downwind beyond 12 m sun-flower as buffer crop within adjacent 12-m-wide recipient maize were 4.2, 11.7, and 3.8% for the GM maize, the kernel color, and the molecular marker test system compared with clover-grass with 4.3, 9.6, and 3.6%. Pronounced edge effects were detected at the edges of recipient maize fields. Based on the present study, growing sunflower as a tall crop between GM and non-GM maize cannot be recommended as an appropriate coexistence measure.

Resveratrol is a phytoalexin produced in various plants like wine, peanut or pine in response to fungal infection or UV irradiation, but it is absent in members of the Brassicaceae. Moreover, resveratrol and its glucoside (piceid) are considered to have beneficial effects on human health, known to reduce heart disease, arteriosclerosis and cancer mortality. Therefore, the introduction of the gene encoding stilbene synthase for resveratrol production in rapeseed is a tempting approach to improve the quality of rapeseed products. The stilbene synthase gene isolated from grapevine (Vitis vinifera L.) was cloned under control of the seed-specific napin promotor and introduced into rapeseed (Brassica napus L.) by Agrobacterium-mediated co-transformation together with a ds-RNA-interference construct deduced from the sequence of the key enzyme for sinapate ester biosynthesis, UDP-glucose:sinapate glucosyltransferase (BnSGT1), assuming that the suppression of the sinapate ester biosynthesis may increase the resveratrol production in seeds through the increased availability of the precursor 4-coumarate. Resveratrol glucoside (piceid) was produced at levels up to 361 microg/g in the seeds of the primary transformants. This value exceeded by far piceid amounts reported from B. napus expressing VST1 in the wild type sinapine background. There was no significant difference in other important agronomic traits, like oil, protein, fatty acid and glucosinolate content in comparison to the control plants. In the third seed generation, up to 616 microg/g piceid was found in the seeds of a homozygous T3-plant with a single transgene copy integrated. The sinapate ester content in this homozygous T3-plant was reduced from 7.43 to 2.40 mg/g. These results demonstrate how the creation of a novel metabolic sink could divert the synthesis towards the production of piceid rather than sinapate ester, thereby increasing the value of oilseed products.

Seeds of oilseed rape (Brassica napus) accumulate high amounts of antinutritive sinapate esters (SE) with sinapoylcholine (sinapine) as major component, accompanied by sinapoylglucose. These phenolic compounds compromise the use of the protein-rich valuable seed meal. Hence, a substantial reduction of the SE content is considered essential for establishing rape as a protein crop. The present work focuses on the suppression of sinapine synthesis in rape. Therefore, rape (spring cultivar Drakkar) was transformed with a dsRNAi construct designed to silence seed-specifically the BnSGT1 gene encoding UDP-glucose:sinapate glucosyltransferase (SGT1). This resulted in a substantial decrease of SE content in T2 seeds with a reduction reaching 61%. In T2 seeds a high and significant correlation between the contents of sinapoylglucose and all other sinapate esters has been observed. Among transgenic plants, no significant difference in other important agronomic traits, such as oil, protein, fatty acid and glucosinolate content in comparison to the control plants was observed. Maximal reduction of total SE content by 76% was observed in seeds of one homozygous T2 plant (T3 seeds) carrying the BnSGT1 suppression cassette as a single copy insert. In conclusion, this study is an initial proof of principle that suppression of sinapoylglucose formation leads to a strong reduction of SE in rape seeds and is thus a promising approach in establishing rape, currently an important oil crop, as a protein crop as well.

With 2 figures and 4 tables Abstract At the field scale, the co-existence of different farming production systems requires strategies to prevent gene flow between adjacent crops. Oilseed rape produces pollen dispersed by wind and insects and the risks of pollen mediated gene flow are significant for this crop. Cleistogamy, the trait of non-opening flowers, could be used to reduce pollen flow. Cleistogamous oilseed rape genotypes were obtained by INRA in France and were bred in order to improve the stability of this trait. In this paper, we examine the reliability of the cleistogamous trait for two inbred lines. The flower opening level was measured at different dates during the flowering period in six field experiments (three sites × 2 years). The results showed that some flowers were partially opened with rates varying from 0.5% to 33% principally depending on genotypes, trials (site and year) and recording dates. Given that other studies have shown that cleistogamy could reduce pollen dispersal, we consider that, even when partially unstable, cleistogamy could be beneficially used in combination with other means in a containment strategy.

The cultivation of genetically modified (GM) herbicide resistant oilseed rape (Brassica napus) has increased over the past few years. The transfer of herbicide resistance genes via pollen (gene flow) from GM crops to non-GM crops is of relevance for the realisation of co-existence of different agricultural cultivation forms as well as for weed management. Therefore the likelihood of pollen-mediated gene flow has been investigated in numerous studies. Despite the difficulty to compare different experiments with varying levels of outcrossing, we performed a literature search for world-wide studies on cross-fertilisation in fully fertile oilseed rape. The occurrence and frequency of pollen-mediated intraspecific gene flow (outcrossing rate) can vary according to cultivar, experimental design, local topography and environmental conditions. The outcrossing rate from one field to another depends also on the size and arrangement of donor and recipient populations and on the ratio between donor and recipient plot size. The outcrossing levels specified in the presented studies are derived mostly from experiments where the recipient field is either surrounding the donor field (continuous design) or is located as a patch at different distances from the donor field (discontinuous design). Reports of gene flow in Brassica napus generally show that the amount of cross-fertilisation decreases as the distance from the pollen source increases. The evidence given in various studies reveals that the bulk of GM cross-fertilisation occurs within the first 10 m of the recipient field. The removal of the first 10 m of a non-transgenic field facing a GM crop might therefore be more efficient for reducing the total level of cross-fertilisation in a recipient sink population than to recommend separation distances. Future experiments should investigate cross-fertilisation with multiple adjacent donor fields at the landscape level under different spatial distributions of rapeseed cultivars and different cropping systems. The level of cross-fertilisation occurring over the whole field is mainly important for co-existence and has not been investigated in agricultural scale experiments until now. Potential problems with herbicide resistant oilseed rape volunteers arising from intraspecific gene flow can be largely solved by the choice of suitable cultivars and herbicides as well as by soil management.