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Calcium is one of the most limiting factors for the growth and reproduction of peanut, which ultimately affects pod and seed yields. A two-year field experiment was carried out to assess the impact of five calcium applications, including nano-calcium and conventional forms, on growth, leaf nutrient content, yield traits, and quality parameters of three diverse peanut cultivars (Ismailia-1, Giza-5, and Giza-6). The applied calcium applications were calcium sulfate, which is recommended for commercial peanut cultivation and commonly referred to as gypsum (coded as Ca-1), calcium nitrate (Ca-2), nano-calcium nitrate (Ca-3), 50% calcium nitrate + 50% nano-calcium (Ca-4), and 50% calcium sulfate + 50% nano-calcium (Ca-5). Calcium sulfate (gypsum, Ca-1) was soil-supplied during the seedbed preparation as recommended, while the other calcium applications (Ca-2, Ca-3, Ca-4, and Ca-5) were exogenously sprayed three times at 30, 45, and 60 days after sowing. The soil of the experimental site was alkaline, with a high pH of 8.6. The results revealed significant differences among cultivars, calcium applications, and their interactions. The soil-supplied gypsum Ca-1 displayed lower agronomic performance on all recorded growth, leaf nutrient content, yield traits, and quality parameters. On the other hand, the foliar-supplied calcium, particularly Ca-4 and Ca-5, displayed superior effects compared to the other simple calcium forms. Ca-4 and Ca-5 produced significantly higher seed yield (3.58 and 3.38 t/ha) than the simple recommended form (Ca-1, 2.34 t/ha). This could be due to the difficulty of calcium uptake from soil-supplied calcium under high soil pH compared to the exogenously sprayed nano-calcium form. Moreover, the superior performance of Ca-4 and Ca-5 could be caused by the mixture of fertilizers from the synergistic effect of calcium and nitrate or sulfate. Furthermore, the effect of nitrate was applied in nano form in the Ca4 and Ca-5 treatments, which contributed to improving nutrient uptake efficiency and plant growth compared to the other treatments. The peanut cultivar Giza-6 showed superiority for most measured traits over the other two cultivars. The interaction effect between the assessed cultivars and calcium applications was significant for various traits. The cultivar Giza-6 showed a significant advantage for most measured traits with the mixture of 50% calcium nitrate + 50% nano-calcium (Ca-4). Conclusively, the results pointed out the advantage of the exogenously sprayed nano-calcium form combined with calcium nitrate or calcium sulfate for promoting growth, leaf nutrient content, yield, and quality traits of peanut, particularly with high-yielding cultivars under sandy soil with high pH.

Bulb onion is cultivated throughout the world for consumption as vegetable and processed products. Although having high global demand and economic significance, information about genetic diversity and genomic resources is limited. This study investigated the variability of 96 accessions representing seventeen countries. Out of 145 SSR markers, 62 SSRs amplified and 15 SSRs gave consistent polymorphic bands. Fifty three alleles were detected with an average of 3.533 alleles per locus. PIC value ranged from 0.219 (ACM463) to 0.715 (ACM091). Structure and cluster analysis grouped the onion accessions into two clusters. Discriminant analysis of principal components, a tool that maximizes variation between groups while minimizing that within groups, assorted accessions into five clusters. Analysis of molecular variance revealed maximum variation within the populations than among the populations. Highest genetic differentiation (FST = 0.11045; p

Capsicum baccatum is one of the main chili peppers cultivated in South America. However, most studies on genetics and breeding have focused on C. annuum, and not C. baccatum. To gain more insights into C. baccatum genetics and breeding, this work estimated the combinatorial abilities of dedo-de-moca-type chili peppers (C. baccatum var. pendulum) in relation to morphoagronomic and biochemical traits, determined the genetic action involved in the expression of these traits, and identified the superior hybrid combinations. Crosses among the five genotypes in a full diallel mating design resulted in 20 F1 hybrids. Morphoagronomic, phytochemical, and antioxidant data were obtained, and Griffing’s diallel model was used to estimate the general and specific combining ability (GCA and SCA, respectively) as well as the reciprocal effect (RE). High diversity was observed for all traits among the parents and hybrids. Significant effects of GCA, SCA, and RE were also detected for the majority of traits, indicating that additive, non-additive, and cytoplasmic effects are involved in the genetic control of these traits. The non-additive effects were predominant for most traits, and the ‘BRS Mari’ × ‘Mexicali’ and ‘BRS Mari’ × ‘Hortivale’ hybrids were the most promising in terms of their yield per plant and their biochemical traits.

Bulb onion is cultivated throughout the world for consumption as vegetable and processed products. Although having high global demand and economic significance, information about genetic diversity and genomic resources is limited. This study investigated the variability of 96 accessions representing seventeen countries. Out of 145 SSR markers, 62 SSRs amplified and 15 SSRs gave consistent polymorphic bands. Fifty three alleles were detected with an average of 3.533 alleles per locus. PIC value ranged from 0.219 (ACM463) to 0.715 (ACM091). Structure and cluster analysis grouped the onion accessions into two clusters. Discriminant analysis of principal components, a tool that maximizes variation between groups while minimizing that within groups, assorted accessions into five clusters. Analysis of molecular variance revealed maximum variation within the populations than among the populations. Highest genetic differentiation (F(ST) = 0.11045; p

[Abstract] The main goal of this work was to investigate the relationship between the fruit morphology and biochemical composition of peppers (Capsicum spp.). For that purpose, one hundred native varieties from the Andean region, where the genus Capsicum has its origin, were analysed for different phytochemical compounds. In addition, pepper fruits were assessed with the highly precise phenomics tool Tomato Analyzer. The collection showed a broad variability which was more evident within the C. annuum group. On average, C. frutescens accessions displayed the highest levels of solid soluble content, pH, polyphenols and antioxidant activity. The Tomato Analyzer descriptors under the categories of size, shape index, and latitudinal section, mostly contributed to the variance among Capsicum groups. C. annuum hold the larger fruits, whereas C. frutescens comprised fruits of smaller sizes. The correlation analysis revealed that biochemical traits were negatively correlated with the fruit parameters related to size, suggesting that huger fruits contain lower amounts of chemical metabolites. The multivariate approximations demonstrated that Andean peppers assorted according to morphometric and colorimetric characteristics, but independently of their species or geographical origin. Groups of valuable native varieties carrying promising traits were identified. This research was funded by Spanish Institute for Agricultural and Food Research and Technology (INIA), co–financed by the European Regional Development Fund (FEDER) (Project RTA2015-00042-C02-02), and by Xunta de Galicia (Project ED431C 2018/57) Xunta de Galicia; ED431C 2018/57 This research was funded by Spanish Institute for Agricultural and Food Research and Technology (INIA), co–financed by the European Regional Development Fund (FEDER) (Project RTA2015-00042-C02-02), and by Xunta de Galicia (Project ED431C 2018/57)

A broad panel of Capsicum spp. landraces, mostly originating in the Andean region, was assessed with thirteen molecular markers linked to disease resistance and pungency-related traits. Tsw and L4 were the most common loci observed within the collection, although resistant alleles associated to Pvr4, Phyto.5.2, and Cmr1 were also recorded in approximately 30% of pepper genotypes. South America and, namely the Andean region, revealed as a promising source of disease resistances, particularly against potyviruses. Clustering analysis split the collection into forty groups, each one carrying a distinctive combination of resistant alleles. Capsicum annuum and C. chinense showed the greatest variability, while the other Capsicum species generated homogeneous clusters with well-defined haplotypes. Capsicum chinense appeared as the most promising species for breeding purposes, with various accessions showing potential resistance to more than 80% of assessed diseases. PCoA analysis did not show a connection between those resistant genotypes and particular geographical regions. The pungency trait was predicted for 85.5% of pepper accessions. Markers linked to capsinoids content did not amplify or did not displayed polymorphism.

Fifteen onion landraces from Galicia (northwest Spain) were characterised with a set of 25 microsatellite markers and the genetic variability harboured by this collection was compared with the surrounding diversity by comparison with a representative panel of European onion landraces. Twenty markers were polymorphic allowing the detection of 121 alleles. Ninety-one of these were identified in the Galician group (average of 4.6 distinct alleles per locus) and 9% of the total number of alleles were recorded as unique alleles specifically contributed by onion landraces from northwest Spain. High values of observed and expected heterozygosities were detected for the majority of loci. Wright’s fixation index confirmed an excess of heterozygotes and a low level of inbreeding, suggesting that high levels of heterogeneity have accumulated within landraces. Multivariate and STRUCTURE analyses revealed that Galician onions possessed a specific genomic composition different from that found in European landraces.

Seventeen onion landraces from North-West Spain were evaluated using microsatellites markers. Eleven polymorphic markers identified 32 alleles in the whole collection, with an average of 2.9 alleles per locus. High values of observed (mean of 0.45) and expected heterozigosity (mean of 0.51) were detected for the majority of loci. Wright?s fixation index confirmed an excess of heterozygotes and a low level of inbreeding within the collection. Multivariate analyses revealed that Oimbra was the most distinctive genotype. The remaining 16 onion genotypes were in part assorted according to some morphological traits of bulbs. Pungency and solid soluble content highly varied among landraces and bulbs. Five landraces were classified as sweet, whereas 9 possessed medium pungency and 3 were recorded as pungent. This onion collection represents a useful source of genetic heterogeneity that might be exploited in breeding programs for the generation of new onion varieties that satisfy consumer demands.

25 Pags., 5 Tabls., 2 Figs. The definitive version, with all the supplementary materials, is available at: http://link.springer.com/journal/122, Scald, caused by Rhynchosporium commune, is one of the most prevalent barley diseases worldwide. A search for new resistance sources revealed that Spanish landrace-derived lines SBCC145 and SBCC154 showed outstanding resistance to scald. They were crossed to susceptible cultivar Beatrix to create large DH-mapping populations of 522 and 416 DH lines that were scored for disease resistance in the greenhouse using two R. commune isolates. To ascertain the pattern of resistance, parents and reference barley lines with known scald resistance were phenotyped with a panel of differential R. commune isolates. Subpopulations were genotyped with the Illumina GoldenGate 1,536 SNP Assay and a large QTL in the centromeric region of chromosome 3H, known to harbour several scald resistance genes and/or alleles, was found in both populations. Five SNP markers closest to the QTL were converted into CAPS markers. These CAPS markers, together with informative SSR markers used in other scald studies, confirmed the presence of the Rrs1 locus. The panel of differential scald isolates indicated that the allele carried by both donors was Rrs1 Rh4 . The genetic distance between Rrs1 and its flanking markers was 1.2 cM (11_0010) proximally and 0.9 cM (11_0823) distally, which corresponds to a distance of just below 9 Mbp. The number and nature of scald resistance genes on chromosome 3H are discussed. The effective Rrs1 allele found and the closely linked markers developed are already useful tools for molecular breeding programs and provide a good step towards the identification of candidate genes., This work was funded by the German BMELV and BLE through the project “Rhynchosporium secalis-resistance in barley (project 28-1-41.009-06) and PLANT KBBE II “ExpResBar” AZ 0315702C and by the Spanish Ministry of Science and Innovation (projects GEN2006-28560-E, AGL2007-63625, RFP2012-00015-00-00, and PLANT KBBE “ExpResBar”, EUI2009-04075), and co-funded by the European Regional Development Fund. CS held an I3P contract from CSIC. BCM is supported by Fundación ARAID, Zaragoza, Spain.

Recent advances in next-generation sequencing techniques and the development of genomics resources for crop plants with large genomes allow the detection of a large number of single nucleotide polymorphisms (SNPs) and their use in a high-throughput manner. However, such large numbers of SNPs are on the one hand not needed in some plant breeding projects and on the other hand not affordable in some cases, raising the need for fast and low-cost innovative techniques for marker detection. In marker selection in plant breeding programs, cleaved amplified polymorphic sequence (CAPS) markers still play a significant role as a complement to other high-throughput methods for SNP genotyping. New methods focusing on the acceleration of CAPS-based genotyping are therefore highly desirable. The combination of the classical CAPS method and a M13-tailed primer multiplexing assay was used to develop an agarose-gel-free protocol for the analysis of SNPs via restriction enzyme digestion. PCR products were fluorescence-labeled with a universal M13 primer and subsequently digested with the appropriate restriction endonuclease. After mixing differently labeled products, they were detected in a capillary electrophoresis system. This method allowed the cost-effective genotyping of several SNPs in barley in a multiplexed manner at an overall low cost in a short period of time. This new method was efficiently combined with the simultaneous detection of simple sequence repeats in the same electrophoresis run, resulting in a procedure well suited for marker-based selection procedures, genotyping of mapping populations and the assay of genetic diversity.

23 Pags., 2 Tabls., 3 Figs. The definitive version is available at: http://link.springer.com/journal/10658, wo major quantitative trait loci (QTLs) associated with resistance to powdery mildew (Blumeria graminis f. sp. hordei) were previously identified on chromosome 7H of the Spanish barley line SBCC097. The two QTLs seemed to share the same chromosomal position as the major genes mlt and Mlf, which were formerly described in Hordeum vulgare ssp. spontaneum-derived lines. In the present work, different lines that carry mlt (RS42-6*O), Mlf (RS137-28*E), or a combination of both (SI-4 and SI-6) were compared with SBCC097 to evaluate their relatedness at the phenotypic, cellular, and genetic levels. The resistance of the lines was characterised by inoculating them with a set of 27 isolates of B. graminis, which displayed a wide range of virulence. It was revealed that SBCC097 possessed a distinctive resistance spectrum. Microscopic assessment of the cytological development of the resistance response showed that SBCC097 clearly formed fewer well-established colonies and secondary hyphae than the other lines. This was confirmed by the infection type recorded after visual inspection. Genetic analyses of all five lines, based on markers flanking the QTLs derived from SBCC097, supported the macroscopic and microscopic data and pointed to the presence of a combination of novel genes or alleles in SBCC097, which may be included in the category of “intermediate-acting” genes, governing resistance mainly at the post-penetration stage., C.S. held a mobility fellowship from the University of Coruña. Part of the results were obtained within the project ExpResBar funded by the German Federal Ministry of Education and Research under grant number 0315702B within the KBBE-II call, and by the Spanish Ministry of Science and Innovation, grant number EUI2009-04075.

Verticillium dahliae is an economically relevant soilborne pathogen that causes vascular wilt in several crops, including pepper (Capsicum annuum). Fungal infection is usually visualized as a vascular browning, likely due to the onset of phenylpropanoid metabolism, which also seems to play a crucial role in the tolerance of some pepper varieties. In the current work, the potential function of distinct phenylpropanoid derivatives (suberin, lignin and phenolic compounds) in the pepper tolerance response against V. dahliae, was investigated. Histochemical and biochemical analyses ruled out suberin as a key player in the pepper-fungus interaction. However, changes observed in lignin composition and higher deposition of bound phenolics in infected stems seemed to contribute to the reinforcement of cell walls and the impairment of V. dahliae colonization. Most importantly, this is the first time that the accumulation of the hydroxycinnamic acid amide N-feruloyltyramine was reported in pepper stems in response to a vascular fungus. Fungitoxic activity for that hydroxycinnamate-tyramine conjugate was demonstrated as well.

24 Pag., 4 Tabl., 2 Fig. The definitive version is available at: www3.interscience.wiley.com

Pepper (Capsicum annuum L.) plants stressed by copper showed less disease symptoms after inoculation with Verticillium dahliae Kleb. We tested if such protection was accompanied of a defence response induced by copper stress by measurement of peroxidase and chitinase activity, phenolics and the expression of four genes related to plant defence. Peroxidase activity, but not chitinase, increased in roots, stem and leaves of copper-stressed plants. However, treating the plants with an ethylene perception inhibitor (MCP) before applying the copper stress, caused a synergic enhancement of both enzymes in stem and cotyledons. Phenolic compounds were also induced by copper but downregulated by MCP in stem. The expression of a peroxidase gene (CAPO1), a sesquiterpene cyclase gene (CASC1), a PR1 gene (CABPR1) and a β-1,3-glucanase (CABGLU) was highly upregulated by copper stress, but MCP neither suppresses nor enhances such an effect. Globally, copper stress causes an induction of defence mechanisms that may partially explain tolerance to Verticillium wilt.

This study investigated the expression pattern of genes encoding for a basic PR-1 protein, a basic beta-1,3-glucanase, a peroxidase, and a sesquiterpene cyclase involved in defense responses in three pepper cultivars with different levels of resistance to Phytophthora capsici. All genes were up-regulated in infected stems of the pepper cultivars, with expression being detected 8h post-inoculation. mRNA levels of these genes increased markedly by 24h post-inoculation, and maximal induction levels were observed for the PR-1 and sesquiterpene cyclase genes. PR-1, peroxidase, and sesquiterpene genes were always expressed at higher levels in resistant cultivars than in the susceptible cultivar, although up-regulation was observed in both, suggesting that the differences between these pepper genotypes in susceptibility and resistance are a matter of the timing and magnitude of the defense response.

43 Pags.- 5 Tabls.- 3 Figs. The definitive version is available at: http://www.sciencedirect.com/science/journal/03044238, Pepper (Capsicum annuum L.) is one of the most valuable vegetables in the world. Over the last decades, highly performing cultivars have progressively replaced the diversified and heterogeneous landraces worldwide, causing wide genetic erosion in this crop. The recovery of these ancient landraces, which might preserve alleles of agricultural interest and local adaptations, results of pivotal importance for the development of new varieties and the maintenance of a sustainable agriculture. In the present work, a collection of twenty-six landrace-derived inbred lines and three landraces from North-West Spain were evaluated for their agronomic performance and genetic diversity based on a set of twenty-seven morphological descriptors and twenty microsatellite markers. The collection featured phenotypic variability for all the studied traits, which were influenced by the location, except for the yield. The principal component analysis divided the landraces in well-defined groups, with only Arnoia, Punxin and Blanco Rosal showing some degree of overlapping. The greater part of the variance was accounted for traits such as fruit weight, pericarp thickness and fruit shape and color. The molecular analyses suggested a high level of genetic diversity within the collection and the presence of specific alleles, which were not previously detected in other Spanish pepper landraces. Multivariate and Bayesian clustering showed that landraces were primarily grouped according to their geographical origin and secondarily in agreement with the characteristics of their fruits. Six groups of landraces, with a great genetic differentiation, were clearly identified. Only the landraces Mougan and Arnoia possessed an allele associated to the pungency character., This work was supported by Xunta de Galicia (Project EM2014/048) and by the Spanish Institute for Agricultural and Food Research and Technology (INIA), co-financed by the European Regional Development Fund (FEDER) (Project RTA2011–00118–C02–02).

Unlocking resistance genes in genbank collections are of prime importance for securing sustainable crop production. In this regard, the Serbian GenBank barley collection, comprising 93 local landraces and 36 commercial cultivars and elite barley breeding lines, was screened for novel resistances to powdery mildew (Blumeria graminis f. sp. hordei) using a set of 28 isolates with a wide spectrum of virulences/avirulences. No line was resistant to all the isolates, but one and three accessions showed resis- tance to 27 and 26 isolates, respectively. Twenty landraces (21.51 %) and ten cultivars (27.78 %) exhibited resistance to 50 % of the isolates. Infection type 2 was most frequent among resistant accessions. Nine B. graminis isolates were sufficient for gene postulation in 73 barley lines. In total, thirty-five different resistance spectra were recorded and the following known resistance genes were postulated namely, Mlra, Mlh, Mla12, Mla7(Mlu), Mlg, MlLa, Mla6, Mla7, Mlt, Mla22, Mlat, Mla1, Mlk. The majority of resistance profiles was constituted by only one line. Unidentified genes alone or in combination were proposed for twenty landraces and six cultivars. This report demonstrated that the barley collection held at the Serbian GenBank could be exploited as a new source for powdery mildew resistance.

14 Pags.- 5 Figs. © Crop Science Society of America. This is an open access article distributed under the CC BY-NC-ND, Powdery mildew causes severe yield losses in barley production worldwide. Although many resistance genes have been described, only a few have already been cloned. A strong QTL (quantitative trait locus) conferring resistance to a wide array of powdery mildew isolates was identified in a Spanish barley landrace on the long arm of chromosome 7H. Previous studies narrowed down the QTL position, but were unable to identify candidate genes or physically locate the resistance. In this study, the exome of three recombinant lines from a high-resolution mapping population was sequenced and analyzed, narrowing the position of the resistance down to a single physical contig. Closer inspection of the region revealed a cluster of closely related NBSLRR (nucleotide-binding site–leucine-rich repeat containing protein) genes. Large differences were found between the resistant lines and the reference genome of cultivar Morex, in the form of PAV (presence-absence variation) in the composition of the NBS-LRR cluster. Finally, a template-guided assembly was performed and subsequent expression analysis revealed that one of the new assembled candidate genes is transcribed. In summary, the results suggest that NBS-LRR genes, absent from the reference and the susceptible genotypes, could be functional and responsible for the powdery mildew resistance. The procedure followed is an example of the use of NGS (next-generation sequencing) tools to tackle the challenges of gene cloning when the target gene is absent from the reference genome.

The aim of this study was to estimate the accuracy and convergence of newly developed barley (Hordeum vulgare L.) genomic resources, primarily genome zipper (GZ) and population sequencing (POPSEQ), at the genome-wide level and to assess their usefulness in applied barley breeding by analyzing seven known loci. Comparison of barley GZ and POPSEQ maps to a newly developed consensus genetic map constructed with data from 13 individual linkage maps yielded an accuracy of 97.8% (GZ) and 99.3% (POPSEQ), respectively, regarding the chromosome assignment. The percentage of agreement in marker position indicates that on average only 3.7% GZ and 0.7% POPSEQ positions are not in accordance with their centimorgan coordinates in the consensus map. The fine-scale comparison involved seven genetic regions on chromosomes 1H, 2H, 4H, 6H, and 7H, harboring major genes and quantitative trait loci (QTL) for disease resistance. In total, 179 GZ loci were analyzed and 64 polymorphic markers were developed. Entirely, 89.1% of these were allocated within the targeted intervals and 84.2% followed the predicted order. Forty-four markers showed a match to a POPSEQ-anchored contig, the percentage of collinearity being 93.2%, on average. Forty-four markers allowed the identification of twenty-five fingerprinted contigs (FPCs) and a more clear delimitation of the physical regions containing the traits of interest. Our results demonstrate that an increase in marker density of barley maps by using new genomic data significantly improves the accuracy of GZ. In addition, the combination of different barley genomic resources can be considered as a powerful tool to accelerate barley breeding. Funding Agencies|German Federal Ministry of Education and Research [AZ 0315702]; Spanish Ministry for Science [EUI2009-04075]; Universidade da Coruna

Phytophthora crown rot, caused by Phytophthora capsici, is potentially the most destructive disease of pepper in Spain. Phenotypic and genetic diversity of 16 P. capsici isolates collected from 11 farms in northwest Spain was characterized based on virulence, mating type, sensitivity to metalaxyl, and genetic analysis using random amplified polymorphic DNA (RAPD) methods. Low variability was observed among the isolates in their metalaxyl response, with 87.5% being highly sensitive. No isolates of the A2 mating type were detected. More variability was found in the virulence assay, and isolates were classified into two groups according to their pathogenicity on a set of four pepper cultivar differentials. Genetic variation examined with eight RAPD primers generated 92 polymorphic bands and revealed the existence of different patterns among isolates. Cluster analysis using the unweighted pair-group method with arithmetic averages (UPGMA) separated the Spanish isolates into three RAPD groups and established a relationship between the Spanish population and a representative worldwide group of isolates. No correlation was found between groups obtained by RAPD analysis and groups defined by virulence or metalaxyl response.

Reliable and sensitive quantification of Phytophthora capsici in pepper plants is of crucial importance in managing the multiple syndromes caused by this pathogen. A real-time polymerase chain reaction (PCR) assay was developed for the determination of P. capsici in pepper tissues. DNA levels of a highly virulent and a less virulent isolate were measured in different pepper genotypes with varying degrees of resistance. Using SYBR Green and specific primers for P. capsici, the minimal amount of pathogen DNA quantified was 10 pg. Pathogen DNA was recorded as early as 8 h postinoculation. Thereafter, the increase was rapid in susceptible cultivars and slower in resistant ones. The amount of pathogen DNA quantified in each pepper genotype correlated with susceptibility to Phytophthora root rot. Likewise, there was a relationship between the virulence of the pathogen and the degree of colonization. Differences also were found in oomycete amount among pepper tissues, with maximal pathogen biomass occurring in stems. The real-time PCR technique developed in this study was sensitive and robust enough to assess both pathogen development and resistance to Phytophthora root rot in different pepper genotypes.

Inoculation of nonhost pepper (Capsicum annuum) plants with the tomato wilt pathogen, Fusarium oxysporum f.sp. lycopersici (FOL), caused no symptoms and the fungus was not recovered from any part of the plant. FOL, however, partially protected pepper plants from subsequent infection with Phytophthora capsici, Verticillium dahliae or Botrytis cinerea by significantly reducing the percentage of diseased plants and the appearance and intensity of symptoms. FOL did not inhibit the mycelial growth of these pathogens in vitro. The protection induced by FOL against Botrytis was inhibited by 1-methylcyclopropene (MCP), an inhibitor of ethylene perception, suggesting the involvement of this hormone in the signalling of FOL-induced resistance. The activities of β-1,3-glucanase and peroxidase 48 h after FOL induction were similar to those in control plants. Chitinase activity, however, was higher in the stems of plants inoculated with FOL. A study of the levels of phenolic compounds revealed that cell-wall-bound phenolics were more abundant in plants treated with FOL, especially in stems, while soluble phenolic contents did not differ.

A PCR-based method was developed for the identification and detection of Phytophthora capsici in pepper plants. Three PCR primers (CAPFW, CAPRV1 and CAPRV2) specific for P. capsiciwere designed based on the sequence of its internal transcribed spacer regions. CAPFW/CAPRV1 amplify a 452 bp product from P. capsici DNA whereas CAPFW/CAPRV2 a 595 bp fragment; neither set amplifies DNA from pepper or several fungi pathogenic to pepper. In conventional (single-round) PCR, the limit of detection was 5 pg DNA for both primer sets, whereas in nested PCR the detection limit for both was of 0.5 fg. However, when the dilution series of target DNA were spiked with plant DNA, amplification declined two-fold in both conventional and nested PCR. The CAPFW/CAPRV2 set in conventional PCR was used to detect P. capsici DNA in inoculated plants. Detection occurred as soon as 8 h post-inoculation in stem samples from infected but still symptomless plants. The method was also tested to detect fungal DNA in infected soils.

12 Pag., 3 Fig., 3 Tabl. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited., Three quantitative trait loci (QTL) conferring broad spectrum resistance to powdery mildew, caused by the fungus Blumeria graminis f. sp. hordei, were previously identified on chromosomes 7HS, 7HL and 6HL in the Spanish barley landrace-derived lines SBCC097 and SBCC145. In the present work, a genome-wide putative linear gene index of barley (Genome Zipper) and the first draft of the physical, genetic and functional sequence of the barley genome were used to go one step further in the shortening and explicit demarcation on the barley genome of these regions conferring resistance to powdery mildew as well as in the identification of candidate genes. First, a comparative analysis of the target regions to the barley Genome Zippers of chromosomes 7H and 6H allowed the development of 25 new gene-based molecular markers, which slightly better delimit the QTL intervals. These new markers provided the framework for anchoring of genetic and physical maps, figuring out the outline of the barley genome at the target regions in SBCC097 and SBCC145. The outermost flanking markers of QTLs on 7HS, 7HL and 6HL defined a physical area of 4 Mb, 3.7 Mb and 3.2 Mb, respectively. In total, 21, 10 and 16 genes on 7HS, 7HL and 6HL, respectively, could be interpreted as potential candidates to explain the resistance to powdery mildew, as they encode proteins of related functions with respect to the known pathogen defense-related processes. The majority of these were annotated as belonging to the NBS-LRR class or protein kinase family. © 2013 Silvar et al., Project ExpResBar, funded by the German Federal Ministry of Education and Research under grant number 0315702B within the KBBE-II call, and by the Spanish Ministry of Science and Innovation, grant number EUI2009-04075. The University of Coruña and the Deutscher Akademischer Austausch Dienst funded mobility fellowships for CS.

25 Pag., 2 Tabl., 3 Fig. The definitive version is available at: http://www.springerlink.com/content/0040-5752/, Twenty-two landrace-derived inbred lines from the Spanish Barley Core Collection (SBCC) were found to display high levels of resistance to a panel of 27 isolates of the fungus Blumeria graminis that exhibit a wide variety of virulences. Among these lines, SBCC145 showed high overall resistance and a distinctive spectrum of resistance compared with the other lines. Against this background, the main goal of the present work was to investigate the genetic basis underlying such resistance using a doubled haploid population derived from a cross between SBCC145 and the elite spring cultivar Beatrix. The population was genotyped with the 1,536-SNP Illumina GoldenGate Oligonucleotide Pool Assay (Barley OPA-1 or BOPA1 for short), whereas phenotypic analysis was performed using two B. graminis isolates. A major quantitative trait locus (QTL) for resistance to both isolates was identified on the long arm of chromosome 6H (6HL) and accounted for ca. 60% of the phenotypic variance. Depending on the B. graminis isolate tested, three other minor QTLs were detected on chromosomes 2H and 7H, which explained less than 5% of the phenotypic variation each. In all cases, the alleles for resistance derived from the Spanish parent SBCC145. The position, the magnitude of the effect observed and the proportion of phenotypic variation accounted for by the QTL on 6HL suggest this is a newly identified locus for broad-based resistance to powdery mildew., This work was funded by the Spanish Ministry of Science and Innovation (projects GEN2006-28560-E, AGL2007-63625 and Plant-KBBE ExpResBar, EUI2009-04075) and co-funded by the European Regional Development Fund. CS holds an I3P postdoctoral contract from CSIC. CS was supported by mobility fellowships from the Deutsche Forschungsgemeinschaft (DFG), CSIC, Fundación Caja Inmaculada and COST Action FA0604 (Tritigen).

30 Pag., 1 Tabl., 5 Fig. The definitive version is available at: http://www.springerlink.com/content/1380-3743/, The Spanish landrace-derived inbred line SBCC97, together with other lines from the Spanish Barley Core Collection, displays high resistance to powdery mildew, caused by the fungus Blumeria graminis f. sp. hordei. The objective of this study was to map quantitative trait loci (QTLs) for resistance to powdery mildew in a recombinant inbred line population derived from a cross between SBCC97 and the susceptible cultivar ‘Plaisant’. Phenotypic analysis was performed using four B. graminis isolates, and genetic maps were constructed with mainly simple sequence repeat (SSR) markers, following a sequential genotyping strategy. Two major QTLs with large effects were identified on chromosome 7H, and they accounted for up to 45% of the total phenotypic variance. The alleles for resistance at each QTL were contributed by the Spanish parent SBCC97. One locus was mapped to the short arm of chromosome 7HS, and was flanked by the resistance gene analogue (RGA) marker S9202 and the SSR GBM1060. This corresponded to the same chromosomal region in which a major race-specific resistance gene from Hordeum vulgare ssp. spontaneum, designated as mlt, had been identified previously. The second QTL was linked tightly to marker EBmac0755, and it shared its chromosomal location with the qualitative resistance gene Mlf, which has only been described previously in the wild ancestor H. spontaneum. This is the first report of these two QTLs occurring together in cultivated barley, and it paves the way for their use in barley breeding programs that are designed to transfer resistance alleles into elite cultivars., This work was supported by the Spanish Ministry of Education and Research (Project AGL2007-63625), and by the European Regional Development Fund. C.S. holds an I3P contract from CSIC. H.D. was supported by a Masters fellowship from IAMZ-CIHEAM.

Inoculation with Fusarium oxysporum f. sp. lycopersici (FOL) protects pepper plants from subsequent infection with Phytophthora capsici. In the present paper, the level of local and systemic protection achieved by plants induced with FOL was evaluated by quantifying the pathogen biomass and using real-time PCR. Differences in the amount of pathogen were found in stems and roots between FOL-treated and untreated plants, while pathogen biomass could not be detected in leaves of induced plants. Five defence-related genes coding for a PR-1 protein, a β-1,3-glucanase, a chitinase, a peroxidase and a sesquiterpene cyclase were up-regulated 48 h after treatment in all the tissues studied, and maximal mRNAs levels were found in leaves., This work was supported by grants from MEC (project AGF99-0301) and XUGA (project PGDIT03RAG10301). C.S. held a fellowship from MEC.

The successful exploitation of germplasm banks, harbouring plant genetic resources indispensable for plant breeding, will depend on our ability to characterize their genetic diversity. The Vegetable Germplasm Bank of Zaragoza (BGHZ) (Spain) holds an important Capsicum annuum collection, where most of the Spanish pepper variability is represented, as well as several accessions of other domesticated and non-domesticated Capsicum spp from all over the five continents. In the present work, a total of 51 C. annuum landraces (mainly from Spain) and 51 accessions from nine Capsicum species maintained at the BGHZ were evaluated using 39 microsatellite (SSR) markers spanning the whole genome. The 39 polymorphic markers allowed the detection of 381 alleles, with an average of 9.8 alleles per locus. A sizeable proportion of alleles (41.2%) were recorded as specific alleles and the majority of these were present at very low frequencies (rare alleles). Multivariate and model-based analyses partitioned the collection in seven clusters comprising the ten different Capsicum spp analysed: C. annuum, C. chinense, C. frutescens, C. pubescens, C. bacatum, C. chacoense and C. eximium. The data clearly showed the close relationships between C. chinense and C. frutescens. C. cardenasii and C. eximium were indistinguishable as a single, morphologically variable species. Moreover, C. chacoense was placed between C. baccatum and C. pubescens complexes. The C. annuum group was structured into three main clusters, mostly according to the pepper fruit shape, size and potential pungency. Results suggest that the diversification of C. annuum in Spain may occur from a rather limited gene pool, still represented by few landraces with ancestral traits.This ancient population would suffer from local selection at the distinct geographical regions of Spain, giving way to pungent and elongated fruited peppers in the South and Center, while sweet blocky and triangular types in Northern Spain. This work was supported by the Spanish Institute for Agricultural and Food Research and Technology (INIA) and co-financed by the European Regional Development Fund (FEDER) (Project RTA2011–00118). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Published