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Esta investigación es parte del proyecto de I+D+i PID2019-108081, financiado por MCIN/ AEI /10.13039/501100011033 y el grupo consolidado de investigación A12 del Gobierno de Aragón Published

5 Pags.- 1 Tabl., Este trabajo tiene como objetivo determinar la estrategia más adecuada para la selección del conjunto mínimo de accesiones (núcleo optimizado) que represente eficientemente la variación genética del manzano conservado en las colecciones españolas. Este núcleo optimizado mediante criterios genéticos constituirá la base de la colección nuclear de conservación, que podrá ser complementado con accesiones seleccionadas por otros criterios (morfo-fisiológicos, agronómicos, valor histórico, etc.). Se ha evaluado la eficiencia de estrategias de selección por búsqueda local estocástica avanzada (ASLS) que diferían tanto por el tamaño final del núcleo como por la combinación (y peso relativo) de las medidas de distancia genética y riqueza alélica a optimizar. Las estrategias empleadas han proporcionado núcleos optimizados con grandes diferencias en la diversidad conservada, así como en el nivel de representación de la estructura genética general. Teniendo en cuenta el uso principal de la colección nuclear, la estrategia que ofrece un mejor equilibrio entre representatividad y adecuación al uso es la que combina la optimización de la distancia media entre cada accesión de la colección y la entrada en el núcleo más cercana con el índice de Shannon y la recuperación de alelos., Este trabajo ha sido financiado por los proyectos INIA RF2011-00017-C05-00 y RTA2015-00052-C02-00

87 Pags.- 3 Tabls.- 5 Figs.- 1 Suppl. Fig.- 5 Suppl. Tabls. The definitive version is available at: http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1744-7348, The nature and structure of genetic diversity in the Spanish apple germplasm preserved at the national level was widely unknown, since studies performed to date on this topic have been exclusively carried out at the regional scale. Here, 1453 accessions from Spanish collections of Malus × domestica were evaluated with a common set of 13 SSR (Simple Sequence Repeats) markers in order to estimate genetic diversity, to identify the underlying genetic structure and to unravel the relationships among them and among a wide set of international cultivars for reference. In total, 737 unique genotypes were identified, 581 diploids and 156 triploids. Using a model-based Bayesian clustering procedure, two reconstructed populations were obtained for diploid genotypes; one retaining only Spanish cultivars (42% of genotypes), and a second containing all foreign cultivars the latter exhibiting evidence supporting the existence of a secondary sub-structure. Similarly, analysis performed on the 156 triploid genotypes also revealed two reconstructed populations; one exclusively associated with local Spanish genotypes (44%). The Jaccard coefficient allowed clustering by UPGMA (Unweighted Pair Group Method) diploid and triploid genotypes, and remarkable differences in allelic composition among the different partitioning levels were found. AMOVA analyses showed moderate but significant differentiation among the main groups (0.08 ≤ FST ≤ 0.12). Our results highlight an important fraction of the Spanish apple germplasm that constitutes a differentiated genepool with respect to the international and commercial apple cultivars. Moreover, the extent of the Spanish genetic diversity was spatially distributed along the northern Iberian Peninsula, suggesting an extensive migration of genotypes along the country. This study is the first valuable action for genetic conservation of apple at the national scale, and constitutes a decisive step towards the definition of a Spanish core collection that will be useful for further studies in dissecting the genetic control of important horticultural traits through genome-wide association analysis in apple., This work was supported by INIA (Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria), under the Project: 'Harmonization of the methodology of characterization, assessment of genetic diversity and definition of the core collection of the apple germplasm conserved in Spanish genebanks (ref. RF2011-00017-C05)'.

1 Pag., A total of 1543 accessions from Spanish collections of Malus x domestica Borkh were evaluated with a set of 13 SSRs, including 11 recommended by ECP/GR Malus/Pyrus WG, in order to estimate their genetic diversity and to identify the genetic structure and relationships among their accessions, as part of the objectives of the project funded by INIA “Harmonization of the methodology of characterization, assessment of genetic diversity and definition of the core collection of the apple germplasm conserved in Spanish genebanks”.

The Spanish Program of Plant Genetic Resources integrates, among others, the collections located at Public University of Navarre, Centro de Investigaciones Agrarias de Mabegondo, Cabildos (Tenerife, La Palma and Gran Canaria), University of Lleida, Estación Experimental de Aula Dei-CSIC and CITA of Aragon. Those collections include mainly local cultivars from their respective regions, covering most of the Spanish apple-growing areas. Though some previous studies about the genetic variability of apple genetics resources from Spain were already performed, a complete analysis is needed in order to evaluate the complete diversity of Malus spp. in Spain. For doing that, the Spanish Government funded the project ¿Harmonization of the methodology of characterization, assessment of genetic diversity and definition of the core collection of the apple germplasm conserved in Spanish genebanks¿. In total, we have evaluated 1206 accessions using standardized methodologies, with SSR markers and morphological descriptors. SSR fingerprinting was performed with 13 SSR markers. SSR profiles were obtained independently and allele sizes were compared using a common set of cultivars selected as references. Results showed 601 genotypes for 1206 accessions. Most of the genotypes (438) were identified only in one accession. The other 163 genotypes were repeated in two to 81 accessions (involving 767 accessions in total). The harmonization of morphological descriptors will allow us to determine if the accessions with the same genotype are synonymies or closely related individuals. Results of this study highlight the interest of coordinated actions in order to optimize the management of germplasm collections and to evaluate the complete genetic diversity of Malus spp. in Spain.

Published Poster number 69

2 Pags., La Red de Colecciones de manzano del Programa Nacional de Recursos Fitogenéticos integra, entre otras, a las colecciones situadas en la Universidad Pública de Navarra (UPNA), el Centro de Investigaciones Agrarias de Mabegondo (CIAM), Cabildos (Tenerife, La Palma y Gran Canaria), la Universidad de Lleida (UdL), el Servicio Regional de Investigación y Desarrollo de Asturias (SERIDA), la Estación Experimental de Aula Dei-CSIC (EEAD) y el Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA). Estas colecciones comprenden mayoritariamente cultivares locales prospectados en sus respectivas regiones y, en conjunto, representan la práctica totalidad de áreas productoras de manzano del país. Las colecciones habían sido caracterizadas, total o parcialmente, con caracteres morfológicos, agronómicos y moleculares, pero los métodos, caracteres y marcadores que se emplearon no estaban estandarizados, por lo que para evaluar de forma global la diversidad conservada por la Red era preciso realizar un trabajo previo de armonización. En este contexto, en 2012 se inició el Proyecto Coordinado "Armonización de la metodología de caracterización, evaluación de la diversidad genética y definición de la colección nuclear de los recursos genéticos de manzano conservados en los Bancos de Germoplasma españoles" (RF2011-00017-COS-OO), financiado por el INIA, e integrado por las colecciones citadas anteriormente. Su objetivo principal es el de optimizar el manejo de los recursos genéticos del manzano conservado en España, desarrollando e implantando metodologías y criterios comunes para la caracterización morfológica, agronómica, tecnológica y molecular de las colecciones. En esta comunicación presentamos los primeros resultados obtenidos de la armonización de las caracterizaciones moleculares., Este trabajo ha sido financiado por el proyecto INIA RF2011-00017-C05-00.

8 páginas.- 3 figuras.- referencias.- Comunicación oral presentada en el XI International Workshop on Sap Flow 7-11 Oct. 2019 in Hyytiälä (Finland), Olive oil is considered as one of the healthiest oils for human consumption due to its high amount of monounsaturated fats and also to the content of antioxidants, polyphenols and triterpenes. Among these last compounds, the oleanolic acid and maslinic acid are of great interest because they are shown to have anti-tumoral and anti-cancer activity. Interestingly, water stress has been observed to enhance these compounds in olive oil. Thus, an irrigation tool based on tree physiology to manage the water stress level would be useful for improving health benefits of olive oil. The general objective of our work was to develop an irrigation approach, based on sap flow-related measurements, to evaluate and control the water stress of olive trees in order to increase the above-mentioned compounds in olive. To achieve this objective we conducted an experiment having four irrigation treatments, where we applied 100, 75, 50 and 25% of the irrigation needs. Sap flow gauges were installed in 16 olive trees, four replicates for each irrigation treatment, to estimate sap flux density by the compensation heat flux method. Sap flux density was used to estimate stomatal conductance in a continuous manner, using a method developed previously for olive. This simulated stomatal conductance was linked to a biochemical model of CO2 assimilation to estimate daily photosynthesis. Moreover, we determined the carbon isotope ratio (δC) in oil of the same monitored trees, as well as the oil compounds above-mentioned. Our results showed that those trees with a higher water supply had higher accumulated photosynthesis on a daily and seasonal basis. Oil δ13C showed the same trend, confirming the effect of stomatal closure on reduction of oil synthesis and the robustness of our methodological procedure to estimate gas exchange from sap flux density dynamics. Furthermore, the level of stomatal conductance achieved correlated inversely with the concentrations of oleanic acid and maslinic acid in the oil. Our results encourage the potential use of sap flow-related measurements to manage irrigation and control the desired level of water stress based on physiological criteria, which could be useful to improve the content of relevant compounds in olives., This work was funded by the Centro para el Desarrollo Tecnológico Industrial and the research project AGL2015-71585-R (Spanish Ministry of Science and Innovation), the European project ERA-NET JPI-Waterworks (PCIN-2017-002, UE) and Grupo Castillo de Canena. A. Pérez-Martı́n and R. Romero helped us with the field measurements.