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Tipa (Tipuana tipu) is a common tree in gardens and carparks, although the shading effect of its canopy must be still characterised to assess the decrease of temperature and quality of irradiance. This work is a preliminary study aimed to assess the effect of shading of tree canopies on the diffuse irradiance pattern received at the soil level in comparison to other conditions. The shade provided by a group of Tipa trees, located at the Universitat Politècnica de València (Valencia, Spain), was evaluated in this experiment and compared to cloudy days and direct sun. Photosynthetic Photon Flux Density (PPFD) and red/near infrared ratios were recorded with a portable spectrometer. Measurements were recorded in January and February 2017, at 10h, 13h and 16h. Depending on the region of the spectrum and time of the day, PPFD values ranged from 0.05 to 0.42, 0.40 to 1.14, and 0.94 to 3.90 μmol·m-2·s-1, for Tipa shade, cloudy days and direct sun, respectively. The spectral analysis of PPFD in cloudy days revealed maximum values in the green region and minimum at near infrared region, while maximum PPFD for tipa shade was mostly found at near infrared, revealing higher importance of this spectral region compared to cloudy days.

Spain is one of the most important centers of diversity for Capsicum annuum peppers, and a plethora of ecotypes can be found throughout the country. These resources represent a valuable genetic pool which must be characterized in depth both morphologically and molecularly. The aim of the present work was to assess phenotypic and genotypic diversity and relationships within some Spanish pepper landraces. A collection of 12 Spanish pepper landraces and 15 foreign controls was characterized with a set of 46 descriptors from International Plant Genetic Resources Institute (IPGRI, now Bioversity International) and genotyped using Genotyping-by-Sequencing (GBS). The studied collection was genetically diverse. The morphological characterization allowed discrimination of the varieties through fruit size, growth habit and others traits. SNP-based phylogenetics clustered together Spanish accessions. Our results provide useful information of several different ecotypes to boost breeding programs.

This work displays the preliminary results of a study of the volatile fraction of fool s watercress (FW) (Apium nodiflorum), an underutilized vegetable species with potential use for salads and as spice. A comparative study of the volatile fraction of FW samples from Northern Valencia periurban area and samples from relatives parsley and celery was performed by head-space solid phase microextraction (HS/SPME) and GC-MS analysis. The profile of FW was richer than the profile of celery and parsley and resulted as a mixture of those ones. Moreover, some volatiles like isothiocyanates were identified as specific of FW. Thus, the flavour of this species can be considered similar to its relatives but more intense and consequently, may be used in salads or even as spice herb.

[EN] Adapting eggplant (Solanum melongena) cultivars to climate change requires the development of drought tolerant cultivars. In order to identify sources of variation for drought tolerance we have characterized nine accessions of eggplant and six of related species for tolerance to drought using a control with optimum irrigation and a drought treatment with a 50% reduction of irrigation. Many differences were found in the materials studied for the four parameters measured (leaf length and width, plant height and dry biomass). The materials with better performance have been S. elaeagnifolium and one accession of eggplant, while the most discriminant traits have been plant height and dry biomass. Overall, the results indicate that there is a large diversity in the germplasm of eggplant and related species for tolerance to drought., This work was completed as part of the initiative “Adapting Agriculture to Climate Change: Collecting, Protecting and Preparing Crop Wild Relatives”, which is supported by the Government of Norway. The project is managed by the Global Crop Diversity Trust with the Millennium Seed Bank of the Royal Botanic Gardens, Kew and is implemented in partnership with national and international gene banks and plant breeding institutes.

Diplotaxis erucoides is an edible plant with potential for marketing. Here, we analysed the influence of the growing conditions in this species, D. tenuifolia and Eruca sativa, and studied the relation among the ascorbic (AA) and dehydroascorbic (DHA) acid forms. Plants were grown in the late winter-spring season under two conditions, greenhouse and field. The contents in AA, DHA and vitamin C (VC) were analysed by HPLC. The content of VC and AA were, in general, remarkable higher in the plants grown in the field. On the other hand, the mean percentage of DHA was less than 11%, being in this case higher for plants grown in the greenhouse. Thus, growing this potential crop in the field seems a better option in order to increase the content in VC, being AA the main form present at the moment of gathering.

Drought is a limiting factor for plant survival and food production. Plants have developed various strategies in response to this stress. The immediate response to drought is the closure of the stomata. However, it prevents the transpiration and the photosynthesis. From the point of view of crops, it is interesting the ability of the plants to keep photosynthesizing under drought. Leaf water content is affected by the difference among leaf and soil water potentials (I¨ leaf -I¨ h ) and by the xylem-specific hydraulic conductivity (Ks). It has been hypothesized that the number and diameter of the xylem vessels would affect the drought tolerance. In this experiment the influence of the xylem anatomy in the tolerance to water stress of three Capsicum sp accessions: Bol 58, Piquillo, Chimayo was studied. Plants were grown in plastic pots filled with soil:sand mixture in a glasshouse at UPV, during spring season. Two different treatments were used in the assay: normal irrigation and restricted irrigation (50% less irrigated than the control). Three and a half months after transplantation plants were harvested; roots, stems and fruits were weighted. Portions of the stem bases were fixed in FPA and rehydrated for the analysis of the xylem total area. Material was sectioned with a freezing microtome and dyed with phloroglucinol. Vessel element area was calculated with Autocad software. There were significant differences of biomass among genotypes and treatments. Piquillo showed lowest reduction of biomass under stress. The genotypes studied showed differences in the xylem structure. In addition, there were changes in the vessel diameter pattern from control to drought conditions. Generally, plants grown under water deficit reduce the number of bigger vessels (>7500µm 2 ). Chimayo was the accession with bigger vessels, in normal and stress conditions, whereas Piquillo had smaller vessels. Therefore results showed a negative correlation between vessel size and production under stress conditions. Big vessels are prone to cavitation and a high proportion of small vessel may contribute to maintain Ks without collapse risk.