Resistance to soil-borne viruses as Soil-borne Wheat Mosaic Virus (SBWMV) has gained evident importance in wheat research and breeding. Very few varieties of bread and durum wheat are resistant to these viruses. Search for new sources of SBWMV is conducted worldwide and loci causing resistance have been described on the B and D genomes of tetraploid and hexaploid wheat. In the present study, a gene locus was identified on the A genome of Triticum monococcum and was successfully transferred to hexaploid wheat. In hexaploid wheat, it is expressed in a stable dominant manner. As this is the first SBWMV resistance gene located on the A genome, this locus is proposed as Sbm3 .

Due to several reasons soil-borne viruses such as the furoviruses, i. e., cereal mosaic virus (SBCMV) and wheat mosaic virus (SBWMV) as well as the bymovirus wheat spindle streak mosaic virus (WSSMV) gained importance in cereal breeding including rye. High yield losses are recorded, today. Since there is no or little resistance to these viruses in modern rye cultivars, an extended screening for resistance was initiated. In addition to earlier screenings, 37 rye genotypes were tested for resistance. Among them, three genotypes were found with persistent resistance to SBCMV. They belong to Secale montanum and S. vavilovii species, i. e., wild types of rye. One accession, PC2243 ( S. montanum ), was used as a resistance donor for the present genetic study. In F2 generation, it was observed that resistance to SBCMV is independently inherited from WSSMV. The evaluation of the ELISA values pointed to a 3:1 distribution assuming duplicate dominant epistasis. Molecular marker analysis supports this segregation pattern. By composite interval mapping a QTL on chromosome 2R could be detected. It can be assumed that there is a DNA region of about 13 cM on the long arm of chromosome 2R (2RL) harboring SBCMV resistance with the closest markers “C9654_1947” and “ isotig11640” . Moreover, genotypes with a yellow seed coat showed practically no infection with SBCMV. Thus, the resistance gene could be linked to the allele an1 determining non expression of anthocyanins. This locus was also mapped earlier on chromosome 2R.

Improved adaptation of potato to limited water availability is needed for stable yields under drought. The maintenance of the cell water status and protection of cellular components against dehydration are important for drought tolerance, and the N status of plants affects the regulation of various respective metabolic processes. A 2-year pot trial with 17 potato cultivars was conducted under a rain-out shelter including two water regimes and two N-levels to investigate genotypic differences concerning osmotic adjustment (OA) and relevant biochemical traits in relation to nitrogen (N) supply. Drought stress resulted in a rapid decrease in the leaf osmotic potential. The N, protein and proline contents increased under drought, while the N protein/N-Kjeldahl ratio decreased. Initially, total soluble sugars increased at both N-levels but dropped back to the control level at high N-availability under prolonged drought while remaining high in N-deficient plants. Results indicate that potatoes have only a limited capacity of active OA and that increasing sugar and proline concentrations are rather associated with the protection of cellular components. High N supply promoted the N protein/N-Kjeldahl ratio at short-term drought and enhanced proline accumulation. Significant genotypic differences were observed for all investigated traits.

Drought stress is an important limitation for potato (Solanum tuberosum L.) production as potato depends on appropriate water availability for high yields of good quality. Therefore, especially in the background of climate change, it is an important goal in potato breeding to improve drought stress tolerance. In this study, 34 European starch potato cultivars were evaluated for drought stress tolerance by growing under well-watered and long-term drought stress conditions in rainout shelters in 2years' pot trials. Besides yield, six physiological traits, that is free proline content, osmolality, total soluble sugar content, chlorophyll content (SPAD), cell membrane stability and crude protein content, were determined in leaves sampled during vegetative growth and during flowering to investigate their association with drought tolerance. ANOVA revealed significant treatment effects for all physiological traits and increased genotypic effects at flowering. The sensitivity of physiological traits to drought was significantly higher during flowering than during vegetative growth. Drought stress decreased starch yield significantly (p < .001), on average by 55%. Starch yield was significantly influenced by genotype and genotypextreatment interactions. Stress tolerance index (STI) calculated from starch yield ranged from 0.26 (sensitive) to 0.76 (tolerant) with significant genotype effects (p <= .001). STI correlated positively with cell membrane stability (r = .59) and crude protein content (r = .38) and negatively with osmolality (r = -.57) and total soluble sugar content (r = -.71). These contrary correlations suggest a dual adaptation strategy in potato under long-term drought stress conditions including increased membrane stability combined with an increased osmolality due to an increased soluble sugar content.

Nine varieties and two breeding lines of sweet Lupinus angustifolius were cultivated under organic and conventional conditions in Northern Germany in growing seasons 2010, 2011 and 2012. The alkaloid content was significantly influenced by the growing system and year and also by genotype. The variety `Vitabor` and the breeding line Bo 083521AR revealed a very low alkaloid content in all years and cropping systems, while `Sanabor`, `Borlu` and `Boregine` had a higher content. In the years 2010-2012 significantly lower alkaloid contents (475 µg/g) were found under organic conditions than under conventional conditions (615 µg/g). The mean alkaloid level of all varieties and breeding lines in organic farming was highest in 2010 (640 µg/g) and lowest in 2012 (364 µg/g), depending on temperature during the seed filling period. Investigations on the yield of L. angustifolius revealed significant effects of the genotype, the year and the growing system. Normal 0 21 false false false DE X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:Normale Tabelle; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:Calibri,sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Times New Roman; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;}

Lupin seeds are gaining attention as highly palatable and healthy ingredients for human food in the last decades. But, lupin cultivars available today in some respect do not meet the requirement for a broad application in the food industry. Important seed quality traits, e.g. protein and alkaloid content, vary considerably depending on environmental conditions. In this study, advanced German breeding lines of narrow-leafed lupins (Lupinus angusufolius L.) were evaluated in 12 environments all over Germany to determine environmental stability and heritability of important agronomic and nutrient traits and to identify environmentally stable genotypes for these traits. Heritability was high for all analysed traits (h(2) > 50%), especially for seed alkaloids (h(2) = 95.2%) and thousand seed weight (h(2) = 94.5%). Out of the genotypes tested one breeding line were identified, which combined constantly low alkaloid content with a high and stable seed protein content and yield. However, results of range and genotypic- and phenotypic coefficient of variation revealed a low genetic diversity within the tested breeding material for most of the traits, which limits the potential for improvement of lupins without broadening the gene pool in German lupin breeding. (C) 2015 Elsevier B.V. All rights reserved.

In the last decades procedures for obtaining protein isolates and concentrates derived from narrow-leafed lupins (L. angustifolius) for human nutrition have been developed. Since this processes starts with defatting of seeds, lupin oil is obtained in large quantities. Therefore, 50 genotypes of L. angustifolius were analysed regarding the fatty acid (FA) composition of seed oil and the environmental stability of fatty acid contents in order to get information on the application of lupin oil in the food industry. The results revealed an n-3/n-6 poly unsaturated fatty acid ratio of 0.13. Furthermore, the seed oil of L. angustifolius contains rather high amounts of saturated FAs (22%). Significant genotypic differences and a high heritability (h(2)>85%) for the content of all fatty acids are suggesting that the potential for genetic improvement of fatty acid composition by breeding is given. However, coefficients of variation below 10% for all considered traits point out that a rapid improvement in seed oil quality will be hindered by the narrow genetic base of the breeding material tested.

Fusarium culmorum causes head blight, produces toxins and reduces yield and quality of cereals. To prevent damage caused by fusarium head blight (FHB), azole fungicides are mainly applied. The occurrence of insensitivity to azoles is a major problem in agriculture. The present study shows that a tebuconazole insensitive strain of F.culmorum can be readily produced in the laboratory, but that the resulting strain of the fungus is of lower fitness in vitro. Insensitivity was confirmed microscopically and by cell viability and metabolic activity. The tebuconazole insensitive strain shows cross insensitivity to nine important azoles. In addition, plants inoculated with the insensitive F.culmorum strain showed no reduction of FHB symptoms and deoxynivalenol (DON) content after tebuconazole treatment, compared to an inoculation with the sensitive strain. Use of wheat cultivars carrying a high resistance level (i.e. cv. Toras) was the most effective method for reducing symptoms and decreasing DON content, independent from the level of fungicide insensitivity of the F.culmorum strain. In conclusion, resistant cultivars and a fungicide mixture which combines different mechanisms of action in fungal metabolism should be applied to avoid fungicide insensitivity of Fusarium spp. in future.

Breeding for resistance against Pyrenophora teres f. teres in barley is difficult due to the high virulence diversity of the pathogen and the fact that in field trials a simultaneous infection with Rhynchosporium commune, Puccinia hordei or Blumeria graminis f. sp. hordei often takes place. To avoid this, a so-called “summer hill trial” was developed in which winter barley is sown at the beginning of August at optimum conditions for P. teres infection. These trials allowed an unequivocal scoring of P. teres resistance. Using this approach, strong correlations of the results obtained in 3 years at two locations were observed and heritability was estimated at h 2 = 0.80 for the doubled haploid (DH) population Uschi × HHOR3073 and h 2 = 0.62 for (Post × Viresa) × HHOR9484. In parallel, genetic maps based on DArT, SSR and SNP markers were constructed, comprising 705.7 cM for the DH population Uschi × HHOR3073 and 1,035.8 cM for (Post × Viresa) × HHOR9484. In the population Uschi × HHOR3073, one quantitative trait locus (QTL) was detected on each of chromosomes 2H and 3H and two on chromosome 5H, explaining between 9.4 and 19.0 % of the phenotypic variance. In the population (Post × Viresa) × HHOR9484, three QTL were detected on chromosome 5H and one on chromosome 7H, explaining between 12.6 and 34.7 % of the phenotypic variance. These results show that the new summer hill trial design is best suited to obtain reliable phenotypic data for P. teres resistance under field conditions, as on the one hand already known QTL were confirmed and on the other hand new QTL were detected.

A H ordeum bulbosum L . ( P oaceae) clone A17 was identified, which showed complete resistance to B arley yellow dwarf virus ( BYDV ) and C ereal yellow dwarf virus ( CYDV ). It was not possible to infect plants of A17 with BYDV ‐ PAV , ‐ MAV , or with CYDV ‐ RPV by the aphid vectors R hopalosiphum padi ( L .) or S itobion avenae ( F abricius) (both H emiptera: A phididae). Plants of the A17 clone and of the BYDV ‐susceptible H . bulbosum clone A21 revealed some resistance to R . padi compared to the susceptible winter barley cultivar R ubina [ H ordeum vulgare L . ( P oaceae)]. The development time to the imago was longer and the number of nymphs was reduced on both clones compared with cv. R ubina. The probing and feeding behaviour of R . padi on plants of the H . bulbosum clones was studied over 12 h and compared with that on plants of the barley cv. R ubina. Principal component analysis of the results of the feeding behaviour revealed a clear separation of the H . bulbosum genotypes from R ubina. On H . bulbosum the number of penetrations was higher but total feeding time was shorter. Significant differences were mainly found in the phloem feeding parameters for plants of both clones in comparison to R ubina, with the virus resistant A17 clone having the strongest effect and the susceptible A21 clone being intermediate. Most significant differences were found in parameters of the phloem salivation phase. On A17, an average of less than one (0.9) E1 phase per plant was observed (3.3 on A21 and 5.7 on R ubina) and its duration was reduced to less than 1 min (0.9 min) in comparison to 2.4 min on A21 and 5.7 min on R ubina. Also, the phloem feeding (E2) phase was clearly reduced on A17 plants with 0.5 E2 phases per test and a mean duration of 1.1 min in contrast with 2.9 and 3.5 E2 phases per test and 34.1 and 421.3 min for A21 and R ubina, respectively. These results point towards a phloem‐localized factor for aphid resistance in H . bulbosum , i.e., on A17 plants the phloem salivation time is too short for a successful infection by BYDV leading to vector resistance.

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In Germany, the first six-rowed waxy winter barley cultivar (cv.) 'Waxyma' was registered in 2008. Besides changes in starch composition, waxy barley is rich in beta-glucans offering new applications in the food industry as beta-glucans reduce the blood cholesterol level. To investigate the stability of the beta-glucan content, cv. 'Waxyma', three waxy breeding lines and the non-waxy cv. 'Lomerit' were grown in field trials, shelter-, green house-and growth chamber experiments. Besides this, 'Waxyma' was grown in field trials at varying nitrogen levels and different seed rates, both with and without fungicide treatment. Waxyma showed a significant increase of the beta-glucan content under optimal nitrogen fertilization and fungicide treatment, but the influence of the seed density was not significant. Under shelter and greenhouse conditions, the influence of drought stress during grain filling was analyzed. The increase of the beta-glucan content under drought stress in the shelter and under rising temperatures in growth chambers was only significant for the non waxy cv. 'Lomerit' while no influence of drought stress was observed under green house conditions. In summary, the high beta-glucan content of cv. 'Waxyma' seems to be relatively stable with respect to growing conditions making it a suitable raw material for human nutrition.

Field studies were conducted in growing seasons 2004, 2005, and 2010 to investigate the effect of different soil pH values on the alkaloid content in seeds of Lupinus angustifolius. Two-year experiments with eleven cultivars were carried out in acid soils with an average of pH = 5.8 (Mecklenburg-Western Pomerania) and on calcareous soils with an average pH of 7.1 (Bavaria), respectively. In addition, in 2010, eight cultivars were grown in field experiments in soils with pH values varying between pH = 5.3 and pH = 6.7. In all experiments conducted on soils with a higher pH (pH = 6.7 and pH = 7.1), a significantly lower alkaloid content was detected in all Lupinus angustifolius cultivars than on soils with a lower pH (pH = 5.3 and pH = 5.8). Results clearly show that the alkaloid content is significantly influenced by the soil pH but genotypic differences regarding the reaction to different pH values in the soil were observed.

Leaf rust, caused by Puccinia hordei Otth, is an important disease of barley (Hordeum vulgare L.) in many areas of the world. The appearance of new virulent races necessitates the identification of new resistance genes in barley. Screening of spring barley landraces from former Yugoslavia led to the identification of an accession (MBR1012) carrying resistance to the most widespread virulent leaf rust pathotypes in Europe. Ninety-one doubled haploid lines derived from a cross between landrace MBR1012 and the susceptible German cultivar Scarlett were evaluated for resistance to P. hordei isolate I-80 and segregated 48 resistant : 43 susceptible (\( \chi_{1:1}^{2} = \, 0.29, \) p = 0.6), indicating a monogenic inheritance of resistance. Using simple sequence repeats (SSR) and single nucleotide polymorphism (SNP) markers, the resistance gene in MBR1012 was mapped to the telomeric region of chromosome 1HS. This gene is assigned the temporary locus designation of Rph MBR1012 until it can be unequivocally determined to be different from all previously reported resistance genes. The closest flanking markers for Rph MBR1012 are located 0.8 cM distal (SNP marker GBS546 and SSR marker GBMS187) and 6.0 cM proximal (SSR marker GMS21). The diagnostic value of the closest linked markers was assessed in a genetically diverse collection of 51 susceptible and resistant barley lines and cultivars. The SSR GBMS187 predicted the presence of Rph MBR1012 with 100% accuracy. However, this marker could not be used singly for the rapid incorporation of resistance into high yielding barley cultivars, since it detects a null allele in MBR1012. Therefore, simultaneous use of the markers closely linked to Rph MBR1012 is needed for transferring Rph MBR1012 into adapted cultivars.

With 2 figures and 4 tables Abstract The Spanish Barley Core Collection, consisting of one hundred and fifty‐nine landrace‐derived inbred lines and sixteen cultivars, was characterized for resistance to powdery mildew ( Blumeria graminis f. sp. hordei ) using a set of 27 isolates with a wide spectra of virulences/avirulences on most of the genes expected to occur in Europe. No landrace‐derived line and no cultivar were resistant to all the isolates but at least three landraces showed infection types below 2 for 23 isolates. Twenty‐two landraces and one cultivar showed resistance against half of the isolates used. Eleven isolates were sufficient to separate the majority of resistance profiles. In total, thirty‐four resistance spectra were detected and fourteen resistance genes/alleles were postulated alone or in combination: MlLa, Mlh, Mlg, Mla22, Mla7(Mlu), Mla7(Mlk), Mlk, Mla12, Mla9, Mla3, Mla6(Mla14), Mlra and Mla1. The majority of resistance spectra are composed only by one line. Resistance in twenty‐one landrace‐derived lines and four cultivars was based on either unidentified genes or combinations of known and unknown genes/alleles. Therefore, the SBCC may be a source for broadening the genetic base of powdery mildew resistance.

With 2 figures and 7 tables AbstractEyespot, caused by Oculimacula acuformis and O. yallundae, is an important disease of wheat (Triticum aestivum). The two pathogens generate similar symptoms and cannot be distinguished visually. In order to distinguish O. acuformis and O. yallundae infections and to identify reliable quantitative differences in the level of resistance of wheat genotypes, two SYBR Green based real‐time PCR assays were developed. The influence of time after inoculation until sample collection, the effect of species (O. acuformis, O. yallundae), and the relevance of wheat cultivars carrying Pch1, Pch2, or none of the resistance genes on the pathogen‐DNA content were analysed. The most clear‐cut difference of pathogen content between resistant and susceptible wheat genotypes was obtained 12 weeks after inoculation with O. yallundae. Growth chamber tests using artificial inoculation with O. yallundae and sampling 12 weeks after inoculation for real‐time PCR is shown to be a reliable procedure to determine the resistance level of wheat against eyespot. Likewise, this is the basis for the development of efficient molecular markers.