Plasma treatment is recognized as a suitable technology to improve germination efficiency of numerous seeds. In this work Quinoa seeds have been subjected to air plasma treatments both at atmospheric and low pressure and improvements found in germination rate and percentage of success. Seed water uptake by exposure to water vapor, although slightly greater for plasma treated seeds, did not justify the observed germination improvement. To identify other possible factors contributing to germination, the chemical changes experienced by outer parts of the seed upon plasma exposure have been investigated by X-ray photoemission spectroscopy (XPS) and scanning electron microscopy (SEM-EDX). XPS revealed that the outer layers of the Quinoa plasma treated seeds were highly oxidized and appeared enriched in potassium ions and adsorbed nitrate species. Simultaneously, SEM-EDX showed that the enrichment in potassium and other mineral elements extended to the seed pericarp and closer zones. The disappearance from the surface of both potassium ions and nitrate species upon exposure of the plasma treated seeds to water vapor is proposed as a factor favoring germination. The use of XPS to study chemical changes at seed surfaces induced by plasma treatments is deemed very important to unravel the mechanisms contributing to germination improvement.

populations from a copper contaminated site and an uncontaminated site, and in the 54 grapevine rootstock "41B", investigating the effects of copper (0-23 mmol l -1 ) on 55 growth, photosynthetic performance and mineral nutrient content. The highest Cu 56 treatment induced nutrient imbalances and inhibited photosynthetic function, causing a 57 drastic reduction in growth in the three study plants. Effective concentration was higher 58 than 23 mmol l -1 Cu in the wild grapevines and around 9 mmol l -1 in the "41B" plants. 59The wild grapevine accessions studied controlled root Cu concentration more efficiently 60 than is the case with the "41B" rootstock and must be considered Cu-tolerant.

1The adaptation capacity of olive trees to different environments is well recognized. 2 However, the presence of microorganisms in the soil is also a key factor in the response of 3 these trees to drought. The objective of the present study was to elucidate the effects of 4 different arbuscular mycorrhizal (AM) fungi coming from diverse soils on olive plant 5 growth and water relations. Olive plants were inoculated with native AM fungal 6 populations from two contrasting environments, i.e. semi-arid -Freila (FL) and humid -7 Grazalema (GZ) regions, and subjected to drought stress. Results showed that plants grew 8 better on GZ soil inoculated with GZ-fungi, indicating a preference of AM fungi for their 9 corresponding soil. Also under these conditions, the highest AM fungal diversity was 10 found. However the highest root hydraulic conductivity (Lp r ) value was achieved by plants 11 inoculated with GZ fungi and growing in FL soil under drought conditions. So, this AM 12 inoculum also functioned in soils from different origins. Nine novel aquaporin genes were 13 also cloned from olive roots. Diverse correlation and association values were found among 14 different aquaporin expressions and abundances and Lp r , indicating how the interaction of 15 different aquaporins may render diverse Lp r values. 16 17

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Wild subspecies of Olea europaea constitute a source of genetic variability with huge potential for olive breeding to face global changes in Mediterranean-climate regions. We intend to identify wild olive genotypes with optimal adaptability to different environmental conditions to serve as a source of rootstocks and resistance genes for olive breeding. The SILVOLIVE collection includes 146 wild genotypes representative of the six O. europaea subspecies and early-generations hybrids. These genotypes came either from olive germplasm collections or from direct prospection in Spain, continental Africa and the Macaronesian archipelago. The collection was genotyped with plastid and nuclear markers, confirming the origin of the genotypes and their high genetic variability. Morphological and architectural parameters were quantified in 103 genotypes allowing the identification of three major groups of correlative traits including vigor, branching habits and the belowground-to-aboveground ratio. The occurrence of strong phenotypic variability in these traits within the germplasm collection has been shown. Furthermore, wild olive relatives are of great significance to be used as rootstocks for olive cultivation. Thus, as a proof of concept, different wild genotypes used as rootstocks were shown to regulate vigor parameters of the grafted cultivar "Picual" scion, which could improve the productivity of high-density hedgerow orchards.