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33 Pags.- 6 Figs.- 1 Tabl. The definitive version is available at: https://www.sciencedirect.com/journal/scientia-horticulturae, The preservation of viable pollen is essential to overcome the problems related to the asynchronous flowering of the parental lines in onion hybrid breeding programs. The aim of this study was to establish a simple, inexpensive, and easily reproducible protocol for medium-term onion pollen storage. First, the conditions for assessing the in vitro pollen germination were optimized. The liquid medium favored the counting of germination of pollen grains in comparison to the solid medium. The addition of 75 mg/l Ca(NO3)2. 4H2O to the medium did not improve pollen germination, while that of 150 mg/l Ca(NO3)2. 4H2O inhibited pollen germination. The highest germination percentage was achieved by incubation at 30–35 °C in the dark. Second, fresh or dehydrated pollen (maintained in a desiccator with silica gel at 25 °C for 18 h) was stored at 4, –20, and –80 °C for two years to study pollen preservation. In addition, the viability and germination capacity of stored pollen were periodically evaluated at 0, 15 and 30 days; 2 and 6 months; and 1 and 2 years. Pollen viability was best retained at low relative humidity and temperatures below zero. Dehydration was essential for pollen preservation at –20 and –80 °C. The results showed that dehydrated pollen stored at –20 °C could be used, with guarantees, for pollination throughout the flowering season. However, the highest viability and in vitro germination percentages after two years of storage (29 and 32%, respectively) were achieved with dehydrated pollen stored at –80 °C. Finally, the capacity of stored pollen to produce seeds was confirmed in crosses with male sterile lines. In this way, dehydrated pollen stored at –80 °C for two years produced an average of 47.9 seeds/100 flowers, representing 43% of the seed in the control crosses. This is the first report in onion research of seed production after pollination with preserved pollen at –80 °C for two years., OF was a recipient of a predoctoral fellowship from the Spanish Ministry of Economy and Competitiveness FPI (INIA-FEDER). This work was supported by the Spanish Ministry of Economy and Competitiveness INIA-FEDER (RTA2015-00042-C02-01), by the Agreement EEAD-CSIC with CITA-Aragón for “Onion Doubled Haploid Production and Development of a Pollen Preservation Protocol”, and by the Aragon Government (Groups A11-20R and A08-20R).

Quantification, using an accurate analytical approach, of capsinoids and capsaicinoids was performed on three chili pepper (Capsicum spp.) genotypes: “Chiltepı́n”, “Tampiqueño 74”, and “Bhut Jolokia” at various stages of fruit development. The accumulation of capsinoids, in all these peppers started between 10 to 20 days post-anthesis (dpa), increased and reached the highest capsinoid amount at 40 dpa, and then decreased until 60 dpa. Conversely, capsaicinoids could already be determined at 10 dpa in “Bhut Jolokia” and their accumulation pattern was different from that of the capsinoids in this genotype. The capsiate/dihydrocapsiate ratio presented a higher variation between genotypes and developmental stages than the capsaicin/dihydrocapsaicin ratio. Capsinoid ratios (4–24%) and Pun1/pAMT genotyping were determined. These results provide information on the progress of the accumulation of capsinoids in the aforementioned pungent and superhot cultivars and could support future breeding studies toward the understanding of the factors affecting their accumulation., This work forms part of the project RTA2015-00042-C02-01, funded by the National Institute for Agriculture and Food Research and Technology (INIA, Spain) and cofinanced by the European Fund for Regional Development (FEDER, Spain). It was also supported by A11-17R project and OT2017/032 (University of Cadiz, Spain).

[EN] The performance of snake melon [Cucumis melo var. flexuosus (L.)] in organic farming was studied under high biotic and salt stress conditions. Soilborne diseases (mainly caused by Macrophomina phaseolina and Neocosmospora falciformis), combined with virus incidence [Watermelon mosaic virus (WMV), Zucchini yellow mosaic virus (ZYMV), and Tomato leaf curl New Delhi virus (ToLCNDV)] and Podosphaera xanthii attacks, reduced yield by more than 50%. Snake melon susceptibility to M. phaseolina and Monosporascus cannonballus was proved in pathogenicity tests, while it showed some degree of resistance to Neocosmospora keratoplastica and N. falciformis. On the contrary, salt stress had a minor impact, although a synergic effect was detected: yield losses caused by biotic stress increased dramatically when combined with salt stress. Under biotic stress, grafting onto the melon F(1)Pat81 and wild Cucumis rootstocks consistently reduced plant mortality in different agroecological conditions, with a better performance compared to classic Cucurbita commercial hybrids. Yield was even improved under saline conditions in grafted plants. A negative effect was detected, though, on consumer acceptability, especially with the use of Cucurbita rootstocks. Cucumis F(1)Pat81 rootstock minimized this side effect, which was probably related to changes in the profile of sugars, acids, and volatiles. Grafting affected sugars and organic acid contents, with this effect being more accentuated with the use of Cucurbita rootstocks than with Cucumis. In fact, the latter had a higher impact on the volatile organic compound profile than on sugar and acid profile, which may have resulted in a lower effect on consumer perception. The use of Cucumis rootstocks seems to be a strategy to enable organic farming production of snake melon targeted to high-quality markets in order to promote the cultivation of this neglected crop., This work was supported by the Spanish Ministerio de Ciencia, Innovacion y Universidades, cofunded with FEDER funds [project nos. AGL2017-85563-C2-1-R and RTA2017-00061-C03-03 (INIA)], and by PROMETEO project 2017/078 (to promote excellence groups) by the Conselleria d'Educacio, Investigacio, Cultura i Esports (Generalitat Valenciana). AF-L is a recipient of a predoctoral fellowship from Generalitat Valenciana.

Chili pepper (Capsicumspp.) is both an important crop and a model for domestication studies. Here we performed a time course experiment to estimate standardized gene expression profiles across fruit development for six domesticated and four wild chili pepper ancestors. We sampled the transcriptome every 10 days, from flower to fruit at 60 Days After Anthesis (DAA), and found that the mean standardized expression profile for domesticated and wild accessions significantly differed. The mean standardized expression was higher and peaked earlier for domesticated vs. wild genotypes, particularly for genes involved in the cell cycle that ultimately control fruit size. We postulate that these gene expression changes are driven by selection pressures during domestication and show a robust network of cell cycle genes with a time-shift in expression which explains some of the differences between domesticated and wild phenotypes.

The performance of snake melon [Cucumis melo var. flexuosus (L.)] in organic farming was studied under high biotic and salt stress conditions. Soilborne diseases (mainly caused by Macrophomina phaseolina and Neocosmospora falciformis), combined with virus incidence [Watermelon mosaic virus (WMV), Zucchini yellow mosaic virus (ZYMV), and Tomato leaf curl New Delhi virus (ToLCNDV)] and Podosphaera xanthii attacks, reduced yield by more than 50%. Snake melon susceptibility to M. phaseolina and Monosporascus cannonballus was proved in pathogenicity tests, while it showed some degree of resistance to Neocosmospora keratoplastica and N. falciformis. On the contrary, salt stress had a minor impact, although a synergic effect was detected: yield losses caused by biotic stress increased dramatically when combined with salt stress. Under biotic stress, grafting onto the melon F1Pat81 and wild Cucumis rootstocks consistently reduced plant mortality in different agroecological conditions, with a better performance compared to classic Cucurbita commercial hybrids. Yield was even improved under saline conditions in grafted plants. A negative effect was detected, though, on consumer acceptability, especially with the use of Cucurbita rootstocks. Cucumis F1Pat81 rootstock minimized this side effect, which was probably related to changes in the profile of sugars, acids, and volatiles. Grafting affected sugars and organic acid contents, with this effect being more accentuated with the use of Cucurbita rootstocks than with Cucumis. In fact, the latter had a higher impact on the volatile organic compound profile than on sugar and acid profile, which may have resulted in a lower effect on consumer perception. The use of Cucumis rootstocks seems to be a strategy to enable organic farming production of snake melon targeted to high-quality markets in order to promote the cultivation of this neglected crop.

[EN] The sexual expression of watermelon plants is the result of the distribution and occurrence of male, female, bisexual and hermaphrodite flowers on the main and secondary stems. Plants can be monoecious (producing male and female flowers), andromonoecious (producing male and hermaphrodite flowers), or partially andromonoecious (producing male, female, bisexual, and hermaphrodite flowers) within the same plant. Sex determination of individual floral buds and the distribution of the different flower types on the plant, are both controlled by ethylene. A single missense mutation in the ethylene biosynthesis geneCitACS4, is able to promote the conversion of female into hermaphrodite flowers, and therefore of monoecy (genotypeMM) into partial andromonoecy (genotypeMm) or andromonoecy (genotypemm). We phenotyped and genotyped, for theM/mlocus, a panel of 207 C. lanatusaccessions, including five inbreds and hybrids, and found several accessions that were repeatedly phenotyped as PA (partially andromonoecious) in several locations and different years, despite beingMM. A cosegregation analysis between a SNV inCitACS4and the PA phenotype, demonstrated that the occurrence of bisexual and hermaphrodite flowers in a PA line is not dependent onCitACS4, but conferred by an unlinked recessive gene which we calledpa. Two different approaches were performed to map thepagene in the genome ofC. lanatus: bulk segregant analysis sequencing (BSA-seq) and genome wide association analysis studies (GWAS). The BSA-seq study was performed using two contrasting bulks, the monoecious M-bulk and the partially andromonoecious PA-bulk, each one generated by pooling DNA from 20 F2 plants. For GWAS, 122 accessions from USDA gene bank, already re-sequenced by genotyping by sequencing (GBS), were used. The combination of the two approaches indicates thatpamaps onto a genomic region expanding across 32.24-36.44 Mb in chromosome 1 of watermelon. Fine mapping narrowed down thepalocus to a 867 Kb genomic region containing 101 genes. A number of candidate genes were selected, not only for their function in ethylene biosynthesis and signalling as well as their role in flower development and sex determination, but also by the impact of the SNPs and indels differentially detected in the two sequenced bulks., This work has been funded by grant UAL18-BIO-B017-B, awarded by the call "Proyectos UAL-FEDER " within the framework of the 2014-2020 FEDER-Andalusia Operational Program, as well as by the research group BIO293 of the University of Almeria.

Cucurbit yellow stunting disorder virus (CYSDV) is one of the main limiting factors of melon cultivation worldwide. To date, no commercial melon cultivars resistant to CYSDV are available. The African accession TGR-1551 is resistant to CYSDV. Two major quantitative trait loci (QTLs) have been previously reported, both located near each other in chromosome 5. With the objective of further mapping the gene or genes responsible of the resistance, a recombinant inbred line (RIL) population derived from the cross between TGR-1551 and the susceptible cultivar &lsquo, Bola de Oro&rsquo, was evaluated for resistance to CYSDV in five different assays and genotyped in a genotyping by sequencing (GBS) analysis. The major effect of one of the two QTLs located on chromosome 5 was confirmed in the multienvironment RIL assay and additionally verified through the analysis of three segregating BC1S1 populations derived from three resistant RILs. Furthermore, progeny test using the offspring of selected BC3 plants allowed the narrowing of the candidate interval to a 700 kb region. The SNP markers identified in this work will be useful in marker-assisted selection in the context of introgression of CYSDV resistance in elite cultivars.

Interest in the consumption of the fruits of pepper (Capsicum spp.) is not only due to its organoleptic characteristics, but also due to its bioactive compounds content, which are reported to provide essential benefits to human health. However, the amount and diversity of these compounds in each fruit specimen depend on its genotype and on a number of environmental factors. This work describes the quantitative ultra-high-performance liquid chromatography coupled to photodiode-array (UHPLC-PDA) analysis of the capsinoids content in four varieties of pepper (‘Habanero’, ‘Habanero Roxo’, ‘Bode’, and ‘Malagueta’) grown until different development stages in a greenhouse under controlled conditions. In all the varieties analyzed, capsiate was the only capsinoid found. The accumulation of capsiate, in all the pepper varieties, started from the 10th to the 20th day post-anthesis (dpa), and increased during the first days (between the 20th and the 27th dpa). From that moment a drastic reduction took place until the end of the ripening stage, except for ‘Bode’ peppers, where the capsiate content increased from the first harvest point on the 20th dpa up to the 76th dpa. The capsiate accumulation patterns over the development of the fruit has been related to the capsaicionoids accumulation patterns in the same samples of the four varieties of pepper. According to our results, the content evolution of both families of compounds will vary depending on each fruit’s genotype, as well as on environmental conditions. No clear trends have been established and, therefore, an in-depth analysis under controlled conditions should be carried out.

The sexual expression of watermelon plants is the result of the distribution and occurrence of male, female, bisexual and hermaphrodite flowers on the main and secondary stems. Plants can be monoecious (producing male and female flowers), andromonoecious (producing male and hermaphrodite flowers), or partially andromonoecious (producing male, female, bisexual, and hermaphrodite flowers) within the same plant. Sex determination of individual floral buds and the distribution of the different flower types on the plant, are both controlled by ethylene. A single missense mutation in the ethylene biosynthesis gene CitACS4, is able to promote the conversion of female into hermaphrodite flowers, and therefore of monoecy (genotype MM) into partial andromonoecy (genotype Mm) or andromonoecy (genotype mm). We phenotyped and genotyped, for the M/m locus, a panel of 207 C. lanatus accessions, including five inbreds and hybrids, and found several accessions that were repeatedly phenotyped as PA (partially andromonoecious) in several locations and different years, despite being MM. A cosegregation analysis between a SNV in CitACS4 and the PA phenotype, demonstrated that the occurrence of bisexual and hermaphrodite flowers in a PA line is not dependent on CitACS4, but conferred by an unlinked recessive gene which we called pa. Two different approaches were performed to map the pa gene in the genome of C. lanatus: bulk segregant analysis sequencing (BSA-seq) and genome wide association analysis studies (GWAS). The BSA-seq study was performed using two contrasting bulks, the monoecious M-bulk and the partially andromonoecious PA-bulk, each one generated by pooling DNA from 20 F2 plants. For GWAS, 122 accessions from USDA gene bank, already re-sequenced by genotyping by sequencing (GBS), were used. The combination of the two approaches indicates that pa maps onto a genomic region expanding across 32.24–36.44 Mb in chromosome 1 of watermelon. Fine mapping narrowed down the pa locus to a 867 Kb genomic region containing 101 genes. A number of candidate genes were selected, not only for their function in ethylene biosynthesis and signalling as well as their role in flower development and sex determination, but also by the impact of the SNPs and indels differentially detected in the two sequenced bulks.

This research was supported by the Spanish Ministry of Economy and Competitivity co-funded with FEDER (AGL-2008-05687-C02-1, AGL 2011-29516-C02-02, AGL2014-53398-C02-1-R and AGL2014-53398-C2-2-R) and by Generalitat Valenciana through Prometeo Excellence Program (PROMETEO/2017/078).

[Key message]: Loci on LGIV, VI, and VIII of melon genome are involved in the control of fruit domestication-related traits and they are candidate to have played a role in the domestication of the crop., The fruit of wild melons is very small (20–50 g) without edible pulp, contrasting with the large size and high pulp content of cultivated melon fruits. An analysis of quantitative trait loci (QTL) controlling fruit morphology domestication-related traits was carried out using an in vitro maintained F2 population from the cross between the Indian wild melon “Trigonus” and the western elite cultivar ‘Piel de Sapo’. Twenty-seven QTL were identified in at least two out of the three field trials. Six of them were also being detected in BC1 and BC3 populations derived from the same cross. Ten of them were related to fruit morphological traits, 12 to fruit size characters, and 5 to pulp content. The Trigonus alleles decreased the value of the characters, except for the QTL at andromonoecious gene at linkage group (LG) II, and the QTL for pulp content at LGV. QTL genotypes accounted for a considerable degree of the total phenotypic variation, reaching up to 46%. Around 66% of the QTL showed additive gene action, 19% exhibited dominance, and 25% consisted of overdominance. The regions on LGIV, VI, and VIII included the QTL with more consistent and strong effects on domestication-related traits. QTLs on those regions were validated in BC2S1, BC2S2, and BC3 families, with “Trigonus” allele decreasing the fruit morphological traits in all cases. The validated QTL could represent loci involved in melon domestication, although further experiments as genomic variation studies across wild and cultivated genotypes would be necessary to confirm this hypothesis., This work was supported by the Spanish Ministry of Economy and Competitiveness/FEDER grants AGL2012-40130-C02-02, AGL2015-64625-C2-2-R to AJM, AGL2014-53398-C2-2-R to BP, AGL2015-64625-C2-1-R, Centro de Excelencia Severo Ochoa 2016–2020, and the CERCA Programme/Generalitat de Catalunya to JGM and AMMM-H. AD was supported by a JAE-Doc contract from CSIC.

“Naga Jolokia” (Capsicum chinense Jacq.) is a hot pepper variety native to India which has received the attention of the global scientific community due to its high capsaicinoid concentration. The present study evaluated the influence of fruit ripening on the total and individual capsaicinoids, as well as capsiate content. The aim was to determine the optimal moment to harvest the peppers depending on their pungent properties. Ultrasound-assisted extraction (UAE) using methanol as the extraction solvent and reverse-phase ultra-high-performance liquid chromatography (UHPLC-photodiode array (PDA)) were employed. Capsaicinoids gradually accumulated in the peppers from the moment they started growing until they reached a maximum concentration (7.99 ± 0.11 mg g−1 of fresh weight (FW)) at 33 days postanthesis (dpa). For this reason, based on its content of pungent compounds, as it is one of the main attributes of this variety, the optimal time for collection would be on day 33. From then on, there was a sharp decrease (96.35% of the total concentration) due to the peroxidase enzymes. The evolution of the principal capsaicinoids in “Naga Jolokia” peppers had a different behavior with respect to literature reports. After this investigation, these changes in content can be attributed to each pepper genotype. Capsiate content reached it maximum value at 19 dpa (0.27 ± 0.01 mg g−1 of FW). Then, there was a gradual drop due to the activities of different peroxidases. Given the important biological activity of capsaicinoids and capsinoids, the information described here allows for determining the ideal time to harvest “Naga Jolokia” peppers.

‘Cantaloupe’ and ‘Piel de Sapo’ are melon (Cucumis melo L.) varieties cultivated in Spain. In 2018, during a pathogens survey in experimental fields of Valencia and Alicante provinces (southeast Spain), wilt and root rot of melon plants were detected in grafted and ungrafted plants. Disease incidence ranged from 10% (Alicante) to 45% (Valencia). Symptoms included yellowing and wilting of leaves, rotting at the stem base and upper root, and collapse of the entire plant. Samplings were conducted from severely decayed and dead plants. Fragments (0.5 to 1 cm) from rotted lower stems and roots were surface disinfected for 1 min in 1.5% NaOCl, washed twice with sterilized distilled water, and plated onto potato dextrose agar (PDA) with streptomycin sulfate (0.5 g/liter). Plates were incubated at 25°C in the dark for 3 to 5 days. Mycelia resembling Fusarium were isolated and characterized by morphological and molecular methods. Based on their adpressed beige mycelia, growth in concentric rings, and absence of sporodochia, colonies growing on PDA and Spezieller Nahrstoffarmer agar were preliminary identified as belonging to the Fusarium solani species complex. On PDA, colonies were white-greyish to pale-cream growing in concentric rings with beige reverse after 6 days. No sporodochia were observed. Macroconidia were slender, falcate, hyaline, three to five septate 43 (38 to 47) × 4.5 (3.8 to 5.2) µm; aerial microconidia were abundant, borne on short, undifferentiated monophialides, ellipsoidal to reniform, sometimes with a truncate base, and zero to one septate 10 (9.2 to 11.4) × 3.5 (2.5 to 6) µm. Chlamydospores were globose, single or in chains, intercalary and thin- to thick-walled. Sequencing of the internal transcribed spacer (ITS) region, a fragment of translation elongation factor-1α (TEF-1α), and RNA polymerase II (RPB2) partial genes was done using ITS1/ITS4 (White et al. 1990), EF1/EF2 (O’Donnell et al. 1998), and fRPB2-7cF/fRPB2-11aR (Reeb et al. 2004) primers, respectively. After comparisons using BLASTn and the Fusarium ID database (http://www.wi.knaw.nl/fusarium/), eight isolates were identified as Neocosmospora falciformis. The ITS, EF-1α, and RPB2 sequences of isolate CRR 2-6 showed 99% homology with N. falciformis EU329691 (ITS), AB817158 (EF-1α), and EU329650 (RPB2). Sequences were deposited in GenBank with accession numbers MN086327 (ITS), MN509809 (TEF-1α), and MN509810 (RPB2). For pathogenicity tests, isolate CRR 2-6 was grown in 250-ml flasks containing potato sucrose medium for 3 days at 25°C in the dark with constant agitation. Roots of ten 15-day-old Piel de Sapo seedlings grown 6 days in trays with sterilized substrate were submerged into a suspension of 5 × 10⁶ conidia/ml for 2 min and transferred to the plastic containers. Three plants submerged in sterile water served as controls. Plants were incubated in a growth chamber (25°C; 16-h/8-h photoperiod). Scarce development, wilting, and yellowing followed by plant death were observed 15 days postinoculation. Noninoculated controls remained asymptomatic. The fungus was reisolated from all the inoculated plants and identified using ITS, TEF-1α, and RPB2. N. falciformis belongs to the Neocosmospora (Fusarium) solani species complex (O’Donnell et al. 2008). To our knowledge, this is the first report of N. falciformis causing wilt and root rot of melon in Spain. The adoption of molecular-based identification methods should lead to a more precise determination on incidence of the pathogen in this Mediterranean area.

Watermelon and melon crops are affected by some important soil-borne fungal diseases like carbonaceous rot (Macrophomina phaseolina), collapse (Monosporascus cannonballus), or the most important pathology at an economic level, the Fusarium wilt (Fusarium oxysporum f. sp. niveum, F. oxysporum f. sp. melonis, F. solani f. sp. cucurbitae, Neocosmospora falciformis, and N. keratoplastica). The methods commonly used for their control are often ineffective, thus new approaches, as the use of biological control agents, are constantly being sought. This work aimed to isolate, identify, and test endophytic fungi for their antagonistic properties against the three mentioned diseases. For this, about 350 endophytic fungal strains were isolated from asymptomatic watermelon plants. Among these, 7 fungal species were selected to evaluate their antagonistic potential against 14 pathogens. Dual culture assays allowed to select two Trichoderma strains according to the high inhibition rates observed (up to 93%), that were further employed in melon and watermelon plants, showing that some of the pathogens were controlled in terms of disease incidence, exhibiting a decrease up to 67% for T. lentiforme. In addition, three concentrations of Epicoccum purpurascens extract was selected to evaluate the germicide effect, obtaining significant differences in the growth of the pathogens depending on fermentation parameters.

Peppers are fruits with wide genetic variability and multiple ways of being consumed that hold a relevant position in the human diet. Nowadays, consumers are interested in new gastronomic experiences provided by pepper cultivars that present new shapes, colors, and flavors while preserving their bioactive compounds, such as their capsaicinoids and capsinoids. However, numerous changes take place during their development that may alter their biological properties. Therefore, this work evaluates the capsaicinoid and capsiate contents in two traditional varieties of ornamental peppers (&ldquo, Filius Blue&rdquo, and &ldquo, Filius Green&rsquo, &rdquo, ) during fruit maturation. The aim is to determine the ideal harvesting moment depending on the farmer&rsquo, s objective (e.g., achieving a specific color, shape, or flavor, achieving the maximum concentrations of bioactive compounds). The capsaicinoid contents followed different patterns in the two varieties analyzed. The &ldquo, variety exhibited increasing concentrations of capsaicinoids up to the 41st day post-anthesis (dpa), from which point on this trend was reversed. The concentrations in the &ldquo, Filius Green&rdquo, variety increased and decreased several times, reaching maximum concentrations on the 69th dpa. Regarding capsiate contents, both varieties varied in the same way, reaching maximum concentrations on the 34th dpa and then decreasing.

Quantification, using an accurate analytical approach, of capsinoids and capsaicinoids was performed on three chili pepper (

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.

A highly sensitive, selective method has been developed and validated for determination of capsiate and dihydrocapsiate for the first time using HPLC-ESI/MS(QTOF). For both capsinoids, LODs and LOQs were 0.02 and 0.05 µmol/l, respectively. The intra- and interday repeatability values (RSD %) were 0.26–0.41% for retention time, and 2.25–2.11% for peak area. Recoveries were up to 98% and 97% for capsiate and dihydrocapsiate, respectively. This method was successfully applied to quantify capsiate and dihydrocapsiate in eight pepper fruit accessions. Capsinoids were found in the range of 1.21–544.59 μg/g DW for capsiate and of 0.61–81.95 μg/g DW for dihydrocapsiate. In the ‘Tabasco’ accession, capsiate and dihydrocapsiate were quantified for the first time, ranging from 3.09 to 58.76 and 1.80 to 6.94 μg/g DW, respectively. Additionally, the ESI-MS/MS(QTOF) analysis has allowed the tentative identification of two other minor capsinoids by exact mass and fragmentation pattern, in the ‘Bhut Jolokia’ accession., This work forms part of the project RTA2015-00042-C02-01, funded by the National Institute for Agriculture and Food Research and Technology (INIA, Spain) and co-financed by the European Fund for Regional Development (FEDER, Spain). It was also supported for GA-A16 and OT2017/032 (University of Cadiz, Spain). O. Fayos is the beneficiary of an INIA fellowship programme (RTA2011-00118-C02-01).

The evolution of individual and total capsaicinoids content in three pepper varieties of Capsicum chinense Jacq. (&lsquo, Bode&rsquo, (B), &lsquo, Habanero&rsquo, (H), and &lsquo, Habanero Roxo&rsquo, (Hr)) during fruit ripening was studied. The five major capsaicinoids (nordihydrocapsaicin, capsaicin, dihydrocapsaicin, homocapsaicin, and homodihydrocapsaicin) were extracted using ultrasound-assisted extraction and the extracts were analysed by ultra-performance liquid chromatography with fluorescence detection (UHPLC-Fl). The plants were grown in a glasshouse and sampled every 7 days until over-ripening. As expected, the results indicated that the total capsaicinoids content increases during the ripening of pepper fruits. The maximum contents of capsaicinoids were reached at different fruit development stages depending on the cultivar. The &lsquo, pepper presented the greatest total capsaicinoids content (3.86 mg g&minus, 1 fresh weigh, F.W.), followed by the &lsquo, pepper (1.33 mg g&minus, 1 F.W.) and &lsquo, pepper (1.00 mg g&minus, 1 F.W.). In all the samples, capsaicin represented more than 80% of the total capsaicinoids content. Due to the high variability observed in the evolution of capsaicinoids content over the ripening process, this work intends to contribute to the existing knowledge on this aspect in relation to the quality of peppers.

Published

La cebolla ( Allium cepa L.) y el pimiento ( Capsicum spp.) han sido cultivados durante miles de años por sus propiedades medicinales y terapéuticas. En la actualidad, estas propiedades bioactivas promotoras de la salud se han atribuido, principalmente, a la acción de los compuestos responsables de la pungencia de la cebolla y del pimiento. El potencial nutracéutico de los sulfóxidos de cisteína en cebolla y de los capsinoides y capsicinoides en pimiento ha despertado especial interés en las industrias tanto farmacéuticas como agro- alimentarias para el desarrollo de nuevos alimentos funcionales. Además, el aumento de la demanda por los consumidores de alimentos frescos más saludables ha incentivado el desarrollo de nuevos programas de mejora de la calidad dirigidos a la obtención de variedades hortícolas con mayores contenidos en es- tos compuestos nutracéuticos. La presente revisión aborda estos aspectos desde el punto de vista de la com- plejidad de las rutas de biosíntesis de los compuestos y cómo las técnicas analíticas modernas, más preci- sas y sensibles, se han convertido en una herramienta fundamental para el estudio del carácter picante. Onion ( Allium cepa L.) and pepper ( Capsicum spp.) have been cultivated for thousands of years due to their medicinal and therapeutic properties. Nowadays, these health-promoting properties have been attributed to the bioactive compounds responsible for the pungency of onion and pepper. The nu- traceutical potential showed by cysteine sulfoxides in onion and by capsinoids and capsaicinoids in pep- per has given rise to a special interest in the pharmaceutical and food industries for the development of novel functional foods. In addition, the increase in demand for consumers of healthy fresh foods has stimulated the development of breeding programs for obtaining new vegetable varieties with higher contents of nutraceutical compounds. The present review addresses these aspects from the point of view of the complexity of the biosynthesis pathways of such compounds, and as modern analytical techniques, more precise and sensitive, have become a fundamental tool for the study of the pungency. Este trabajo ha sido financiado por los pro- yectos INIA-FEDER (RTA2011-00118-C02-01 y RTA2015-00042-C02-01) y el Gobierno de Aragón (Grupo de Investigación A16). O. Fa- yos es beneficiaria de una beca predoctoral FPI-INIA Sulfóxidos de cisteína capsinoides capsicinoides alimentos funcionales rutas de biosíntesis HPLC S -alk(en)yl-L-cysteine sulfoxides capsinoids capsaicinoids functional foods biosynthesis path- ways HPLC Published

Capsinoids exhibit health-promoting properties and are therefore compounds of interest for medical and food sciences. They are minor compounds present in relatively high concentrations in only a few number of pepper cultivars. It is desirable to quantify capsinoids to provide selected cultivars with high capsinoid contents, which can then be employed as health food product. Quantifying low concentrations of capsinoids from pepper fruit requires a precise and selective analytical technique such as HPLC coupled to electrospray ionization - mass spectrometry, with development of an internal standard essential. In this work, the synthesis method of a novel compound analogue of capsinoids, the (±)-3,4-dimethoxybenzyl-4-methyloctanoate, which could be a suitable internal standard for capsinoid determination by electrospray ionization - mass spectrometry is described.(±)-3,4-dimethoxybenzyl-4-methyloctanoate was stable under the analysis conditions and exerted chemical and physical properties similar to those of capsinoids. This internal standard will provide an accurate capsinoid determination by electrospray ionization - mass spectrometry, thus facilitating the pepper breeding programs, screening pepper cultivars and a better understanding of capsinoid biosynthetic pathway., This study was supported by the National Institute for Agriculture and Food Research and Technology (INIA) and has been co-financed by the European Fund for Regional Development (FEDER) (grant number RTA2011-00118-C02 and RTA2015-00042-C02-00). Also, it was supported for Aragon Government-A16. Author O. Fayos has received research grants from INIA (RTA2011-00118-C02-01).

Severe fruit rot of butternut squash (Cucurbita moschata Duchesne), a fruit widely consumed and cultivated in Spain, was observed in 2016 in cultivated fields and at storage conditions in Valencia Province (southeast Spain). Fruits exhibited sunken lesions that eventually extended into the flesh and led to 10 to 20% postharvest losses. Small (3 to 4 mm) pieces of rotted tissues were surface disinfected for 1 min in 1.5% NaOCl, washed twice with sterilized distilled water, and plated onto potato dextrose agar (PDA) amended with streptomycin sulfate (0.5 g liter–1). Plates were incubated at 25°C in the dark for 3 to 5 days. Fusarium colonies were consistently isolated, transferred to PDA and Spezieller Nährstoffarmer Agar (SNA) culture media for morphological identification, and identified as belonging to the Fusarium solani species complex (FSSC) based on morphology on SNA. Sporodochial macroconidia were 3 to 4 septate in average, slender and slightly curved, 45 (34 to 51) × 4.2 (3.5 to 5) µm; aerial microconidia were abundant, borne on short monophialides, ovoid to reniform, and 8.6 (4.9 to 16.4) × 3.4 (2.7 to 4) µm. The internal transcribed spacer region and elongation factor-1a gene of isolate GIHF-146 were sequenced (using ITS1/ITS4 and EF1-728F/EF1-986R primer pairs) and deposited in GenBank with accession numbers MF535516 (ITS) and MF580776 (EF-1a), respectively. BLASTn comparison of the two sequences showed a 99% homology with those of F. petroliphilum (Q.T. Chen & X.H. Fu) D. Geiser, O’Donnell, Short & Zhang: e.g., LC184243 (ITS) and LC177308 (EF-1a). Comparison of these sequences in the Fusarium ID database (http://www.westerdijkinstitute.nl/fusarium/) exhibited similar levels of similarity...

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.

a b s t r a c t Onion (Allium cepa L.) is one of the most valuable vegetables in the world. However, despite its global culinary and economic significance, the knowledge about onion genetic diversity and resources is limited. The Vegetable Germplasm Bank of Zaragoza (BGHZ) (Spain) holds an important A. cepa L. collection, where most of the Spanish onion variability is represented. Since the genetic diversity of Spanish onion germplasm is an unexploited resource for onion breeding, a total of 85 Spanish onion landraces (A. cepa L.) and 6 related Allium outgroups from the BGHZ collection were studied by means of SSR markers. The results showed that 12 out of the 18 SSR markers amplified were useful and polymorphic to distinguish all the studied onion accessions, allowing the detection of 47 alleles, with an average of 3.9 alleles per SSR, ranging from 2 to 7. Within related Allium species, the total number of detected alleles was 45, with an average of 3.7 alleles per SSR, ranging from 1 to 10. Specific alleles were obtained both in the Spanish onion landraces and in related Allium species, with cross transferability rates ranging from 25.0% to 91.7% in the six Allium species assayed. The resulting UPGMA dendrogram grouped the 91 Allium accessions according to their taxonomical classification, producing 6 main clusters, with all the Spanish onion landraces included in one cluster at a genetic distance of 0.69. These results revealed an interesting reservoir of genetic variability, useful for onion breeding, and confirmed the need to preserve these irreplaceable genetic resources.

Fusarium wilt incited by Fusarium oxysporum f. sp. melonis (Fom) causes severe losses in melon crops. Four physiological races of Fom have been identified: 0, 1, 2 and 1.2. In most cases, resistance to race 1.2 has been described as recessive, polygenic and not race specific. However, some evidence of race-specific effects within melon resistance to race 1.2 has been reported. In this work, we study these effects and assess whether they are due to race-specific resistance. Seeds were obtained from 14 melon accessions that exhibit some level of resistance to race 1.2, and from the lines ‘Charentais-Fom1’ (resistant to races 0 and 2), ‘Charentais-Fom-2’ (resistant to races 0 and 1), and ‘Dinero F1’ (with partial resistance to Fom race 1.2). Melon seedlings were artificially inoculated using two different procedures: ‘continuous shaking’ and ‘tray immersion’. Symptom severity was assessed on leaves using a rating scale from 0 (no symptoms) to 4 (death of the plant). Symptoms were recorded weekly over the four-week period following the first appearance of symptoms and the area under the disease progress curve (AUDPC) was calculated. Six Fom isolates (3 from pathotype Y and 3 from pathotype W) were used in the inoculation. The less aggressive ‘tray immersion’ procedure seems to be more appropriate for detecting the typically small resistance factors of this type of polygenic partial resistance. ‘Kogane Nashi Makuwa’, ‘BG-5384’, ‘Shiro Uri Okayama’, ‘C-211’ and the control, ‘Dinero F1’, showed a high level of resistance to all Fom isolates. However, some genotype × isolate effects were also detected. ‘Baza’, when inoculated with isolate Fom 9302, and ‘Korca, when inoculated with Fom 37mls.1.2W, showed resistance levels similar to that of ‘Dinero F1’; this effect was not observed when ‘Baza’ and ‘Korca’ were inoculated with other isolates. These results are characteristic of race-specific resistance and offer evidence for the presence of this type of resistance to Fom race 1.2 in melons.

This study was supported by the Spanish Ministry of Science (project INIA RTA2008-00095-00-00)and by the Aragon Gobernment (Group A16)

Pungency in Capsicum spp. is an important quality trait for pepper breeding. The perception of pungency in pepper is due to the presence of a group of compounds named capsaicinoids, only found within the Capsicum genus. How pungency is controlled at genetic and molecular levels has not been completely elucidated. The use of molecular markers to assess pungency trait is required for molecular breeding, despite the difficulty of development of universal markers for this trait. In this work, a DNA sequence possibly related to pungency with a high similarity to Pun1 locus was studied, and sequence analysis of this homolog revealed a 15 bp deletion in non-pungent pepper accessions. An allele-specific pair of primers was designed and specific fragments of 479 bp from non-pungent and 494 bp from pungent accessions were obtained. Polymorphism of this marker, named MAP1, was tested in a wide range of accessions, belonging to several Capsicum species, including pungent and non-pungent accessions of C. annuum L., and pungent accessions of C. chinense, C. baccatum, C. frutescens, C. pubescens, C. galapagoense, C. eximium, C. tovarii, C. cardenasii, and C. chacoense. All these Capsicum accessions were correctly discriminated. The marker suitability to assess pungency in domesticated and wild Capsicum species was demonstrated, and therefore it will be very useful in marker assisted selection (MAS). Moreover, MAP1 was located in a saturated pepper linkage map and its possible relationship with the Pun1 locus has been discussed. Among the available markers for this complex quality trait, the marker developed in this study is the most universal so far.

28 Pags.- 6 Tabls.- 1 Fig. This Document is Protected by copyright and was first published by Frontiers. All rights reserved. it is reproduced with permission (Creative Commons Attribution License)., The use of doubled haploids in onion breeding is limited due to the low gynogenesis efficiency of this species. Gynogenesis capacity from Spanish germplasm, including the sweet cultivar Fuentes de Ebro, the highly pungent landrace BGHZ1354 and the two Valenciana type commercial varieties Recas and Rita, was evaluated and optimized in this study. The OH-1 population, characterized by a high gynogenesis induction, was used as control. Growing conditions of the donor plants were tested with a one-step protocol and field plants produced a slightly higher percentage of embryogenesis induction than growth chamber plants. A one-step protocol was compared with a twostep protocol for embryogenesis induction. Spanish germplasm produced a 2 to 3 times higher percentage of embryogenesis with the two-step protocol, Recas showing the highest percentage (2.09%) and Fuentes de Ebro the lowest (0.53%). These percentages were significantly lower than those from the OH-1 population, with an average of 15% independently of the protocol used. The effect of different containers on plant regeneration was tested using both protocols. The highest percentage of acclimated plants was obtained with the two-step protocol in combination with Eco2box (70%), whereas the lowest percentage was observed with glass tubes in the two protocols (20- 23%). Different amiprofos-methyl (APM) treatments were applied to embryos for chromosome doubling. A similar number of doubled haploid plants were recovered with 25 or 50 μM APM in liquid medium. However, the application of 25 μM in solid medium for 24 h produced the highest number of doubled haploid plants. Somatic regeneration from flower buds of haploid and mixoploid plants proved to be a successful approach for chromosome doubling, since diploid plants were obtained from the 4 regenerated lines. In this study, doubled haploid plants were produced from the four Spanish cultivars, however further improvements are needed to increase their gynogenesis efficiency., O. Fayos was a recipient of a predoctoral fellowship from the Spanish Ministry of Economy and Competitiveness FPI (INIA-FEDER). This work was supported by the Spanish Ministry of Economy and Competitiveness INIA-FEDER (RTA2011-00118- C02-01), by the Agreement EEAD-CSIC with CITA-Aragón for Onion Doubled Haploid Production and the Aragon Government (Group A16 and Group A06).

A new Rhizoctonia-like fungus associated with ectomycorrhizal tips of evergreen oak inoculated with Tuber melanosporum is described. Tulasnella tubericola sp. nov. is characterized by its particular habitat, apparently not associated with the roots of any orchid species, its fast-growing rate in plate culture, the creamy-white to pale orange tones of the colonies, the production of both typical globose monilioid cells together with terminal, finger-like monilioid projections and the absence of true sclerotia. In addition, phylogenetic analyses based on the sequences of the internal transcribed spacer (ITS) region of the ribosomal DNA (rDNA) showed that the different isolates that define the new species constitute an isolated, monophyletic lineage within the genus. The fungus is exclusively isolated from mycorrhizal roots of Quercus ilex subsp. ballota, being absent both in the culture substrate or in the natural soil employed in the mycorrhization processes. No sexual fruiting bodies have been observed or induced in the laboratory for this fungus.

Published

The ontogenetic variation of total and individual capsaicinoids (nordihydrocapsaicin (n-DHC), capsaicin (C), dihydrocapsaicin (DHC), homocapsaicin (h-C) and homodihydrocapsaicin (h-DHC)) present in Malagueta pepper (Capsicum frutescens) during fruit ripening has been studied. Malagueta peppers were grown in a greenhouse under controlled temperature and humidity conditions. Capsaicinoids were extracted using ultrasound-assisted extraction (UAE) and the extracts were analyzed by ultra-performance liquid chromatography (UHPLC) with fluorescence detection. A significant increase in the total content of capsaicinoids was observed in the early days (between 12 and 33). Between day 33 and 40 there was a slight reduction in the total capsaicinoid content (3.3% decrease). C was the major capsaicinoid, followed by DHC, n-DHC, h-C and h-DHC. By considering the evolution of standardized values of the capsaicinoids it was verified that n-DHC, DHC and h-DHC (dihydrocapsaicin-like capsaicinoids) present a similar behavior pattern, while h-C and C (capsaicin-like capsaicinoids) show different evolution patterns. Published