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This is the peer reviewed version of the following article: [FULL CITE], which has been published in final form at [Link to final article using the DOI]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving., [EN] BACKGROUND: The grafting of watermelons (Citrullus lanatus) is a common technique that increases yield under stressful soil conditions. Themost common rootstocks for watermelons are Cucurbita hybrids. However, they often have a negative impact on fruit quality. Exploiting novel Citrullus germplasm such as citronmelon (Citrullus lanatus var. citroides) is an alternative to avoid these quality problems. RESULTS: Citron melon has been validated as watermelon rootstock, comparing its effects on watermelon quality to those of Cucurbita hybrids. Larger fruits with thicker rinds were observed in fruits from plants grafted onto both citron and Cucurbita rootstocks. The citron melon had no significant effect on flesh sugars or acid profiles compared to non-grafted watermelons, except for an increase in glucose and malic acid content, which also occurred in the Cucurbita rootstocks. The aroma profile of fruits produced on citron melon was similar to that of the non-grafted and self-grafted controls. The citron rootstock did not display the increased levels of (Z)-6-nonen-1-ol (a compound associated with pumpkin-like odors) found in fruits produced with Cucurbita hybrids. CONCLUSION: The low impact of citron melon rootstock on fruit quality, along with the enhanced resistance against nematodes, make the citron a promising alternative to Cucurbita rootstocks. (C) 2016 Society of Chemical Industry

[EN] The influence of irrigation doses on standard and high lycopene tomato varieties has been analyzed during two years in one of the main processing tomato growing areas of Spain. Deficit irrigation (75% ETc) implied a mean reduction in water use of 28.2%, while it caused a significant reduction in the marketable production of 16.4% and increase insoluble solids (8.4%) and Hunter a/b ratio (2.4%). The effect on lycopene content was not significant. Increasing irrigation dose over the recommended 100% ETc had no significant effect on the agronomical performance, while it provoked a dilution effect reducing total soluble solids and lycopene content. The effects on 33 tomato volatiles were also analyzed, 11 of them related to main aroma notes and 22 to the background volatile profile. The effect of deficit irrigation on aroma was dependant on climatic conditions and it may either not have a significant effect on the aroma profile or may lead to higher logodor units in main aroma volatiles. High lycopene cultivars showed higher contents in most volatiles, including some volatiles originated in pathways that have not been related with carotenoid degradation processes. In both the fresh and processing tomato market the improvement of organoleptic and functional quality and the reduction of the impact of agriculture on environment represent main goals. The use of high lycopene cultivars and restricted irrigation would enhance the aroma of materials targeted to quality markets, contributing to increase the efficiency of water use in agriculture. (C) 2016 Elsevier B.V. All rights reserved.

The use of a new atmospheric-pressure chemical ionization source for gas chromatography (APGC) coupled with a tandem quadrupole mass spectrometry (MS/MS) system, as an alternative to high-resolution mass spectrometry (HRMS), for the determination of PCDDs/PCDFs is described. The potential of using atmospheric-pressure chemical ionization (APCI) coupled to a tandem quadrupole analyzer has been validated for the identification and quantification of dioxins and furans in different complex matrices. The main advantage of using the APCI source is the soft ionization at atmospheric pressure, which results in very limited fragmentation. APCI mass spectra are dominated by the molecular ion cluster, in contrast with the high energy ionization process under electron ionization (El). The use of the molecular ion as the precursor ion in MS/MS enhances selectivity and, consequently, sensitivity by increasing the signal-to-noise ratios (S/N). For standard solutions of 2,3,7,8-TCDD, injections of 10 fg in the splitless mode on 30- or 60-m-length, 0.25 mm inner diameter (id), and 25 mu m film thickness low-polarity capillary columns (DB5MS type), signal-to-noise (S/N) ratios of >10:1 were routinely obtained. Linearity was achieved in the region (correlation coefficient of r(2) > 0.998) for calibration curves ranging from 100 fg/mu L, to 1000 pg/mu L. The results from a wide variety of complex samples, including certified and standard reference materials and samples from several QA/QC studies, which were previously analyzed by EI HRGC/HRMS, were compared with the results from the APGC/MS/MS system. Results between instruments showed good agreement both in individual congeners and toxic equivalence factors (TEQs). The data show that the use of APGC in combination with MS/MS for the analysis of dioxins has the same potential, in terms of sensitivity and selectivity, as the traditional HEMS instrumentation used for this analysis. However, the APCI/MS/MS system, as a benchtop syst, Funding Agencies:Generalitat Valenciana, as research group of excellence PROMETEO/2009/054Serveis Centrals d'Instrumentacio Cientifica (SCIC) of the University Jaume IChina Scholarship Council 201206400003