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Resumen del trabajo presentado en la 6th International Conference on the Olive Tree and Olive Products, celebrada en Sevilla (España) del 15 al 19 de octubre de 2018., The wide olive genetic patrimony has revealed high variability for most of the agronomic and oil quality traits of interest in olive growing. Few studies, however, have addressed the interaction of this variability with the environment, a subject of particular interest considering the natural high instability of the Mediterranean climate and the challenge of the predicted climate change. The current work presents results on the interaction between genotype and environment from multi-environment trials of olive cultivars and breeding selections, planted in different edaphoclimatic conditions of Andalusia, Southern Peninsular Spain and Canary Islands. For most of the agronomic and oil quality characters evaluated (flowering phenology, flower quality, pattern of oil accumulation, fatty acid composition and phenol content and composition), significant genotype and environment effects have been observed. For example, olive cultivars grown in Tenerife under much milder winter temperatures than in the Iberian Peninsula showed substantially earlierflowering and oil accumulation. Only in the case of flowering phenology was no significant genotype effect found. Furthermore, a strong genotype x environment effect was highly consistent in all characters considered. Regarding resistance to disease, such as Verticillium wilt, the variability of results from both natural and artificial inoculations also tends to indicate a considerable environmental effect and the need for careful testing of disease evolution. All this information strongly suggests the necessity of comparative trials of olive cultivars for both adequate choice of cultivar and final selection in breeding programs.

6 Figuras.-- 1 Tabla, Different scientific evidences suggest that the long term dietary consumption of virgin olive oil (VOO) seems to be related to an attenuation of the inflammatory response and reduction of the associated risk of chronic inflammatory disease states. VOO phenolic compounds are claimed to be the main responsible for these positive health benefits. They are mainly synthetized from phenolic glucosides present in the olive fruit by the action of glucosidases occurring when they come together once the olive fruit is crushed during olive oil extraction. The genetic variability of the major phenolic compounds was studied in a representative sample of olive cultivars (Olea europaea L.) from the World Olive Germplasm Collection established at IFAPA Centre “ Alameda del Obispo in Cordoba, Spain. The most abundant phenolic components found in VOO are the secoiridoid derivatives resulting from the enzymatic hydrolysis of oleuropein, ligstroside and demethyloleuropein present in the fruit, which showed to be on average their main phenolic glucosides. The mean content of phenolic compounds in the oils was 494.51 µg/g oil, displaying a variability range of 63.74-1432.04 µg/g oil. The mean content of phenolic compounds in the fruits was 12384.23 µg/g fruit with a range of 3754.13-30696.39 µg/g fruit. Total phenolic compounds in the fruits and the oils were significantly correlated (r = 0.66). Thus, the composition and biochemical status of the olive fruit seems to be the most important variables determining the synthesis of the VOO phenolic compounds during the oil extraction process. On the other hand, the content of oleuropein and derivatives in the oils and fruits showed a correlation coefficient (r = 0.64) lower than that observed for ligstroside and derivatives (r = 0.73). These findings might be related to the higher oxidation rates of the former due to the action of oxidative enzymes during the oil extraction process as a consequence of the orthodiphenolic structure they possess. Data on phenolic composition would be of interest for the selection of optimal parents in olive breeding programs with the aim of obtaining new cultivars with improved nutritional quality

Virgin olive oil (VOO) represents the primary dietary lipid source in the Mediterranean diet and has been linked to its positive health benefits. VOO metabolites responsible for its nutritional and organoleptic quality include certain components that are transferred almost unchanged from fruit to oil (fatty acids and tocopherols) and other compounds that are synthesized during the oil extraction process by endogenous enzymes from precursors already present in the fruit (volatile and phenolic compounds). The health - promoting characteristics of VOO seems to be related to the high level of oleic acid, an adequate balance of saturated/unsaturated fatty acids, the presence of tocopherols and, specially, the contents of phenolic compounds. Meanwhile, volatile compounds are responsible for its aroma, whereas phenolic compounds are also responsible for the bitter and pungent taste notes of this oil. The final content of these metabolites related to VOO quality is controlled by the levels of expression/activity of the corresponding genes/enzymes involved in their biosynthesis which are cultivar dependent. Given that oil quality is one of the main objectives of the breeding programs aiming at obtaining new olive cultivars, knowledge of the content of these key components for the VOO quality might be very useful for the selection. Moreover, the combination of biochemical and molecular studies would allow to identify the most important genes/enzymes in relation to the oil quality and to know their regulatory mechanisms, so that this knowledge may be used in the molecular marker assisted selection of olive clones with improved oil quality features. For this purpose, the natural variability of the olive species was assessed in a collection of cultivars from the World Olive Germplasm Bank (WOGB) located at Córdoba, and the progeny of a cross of Picual x Arbequina olive cultivars. Analytical data showed that the cultivar collection displayed, in general, a higher level of variability than the progeny cross for most of the metabolites assessed, and that a single cross of olive cultivars might apparently provide enough degree of variability for most of the oil quality traits sought in a breeding program.

VI International Strawberry Symposium. Editor: J. López-Medina., Several strawberry products: whole fruits, strawberry purees (5°Brix) and strawberry concentrates (≥21°Brix), submitted to different processing temperatures (fresh non-pasteurized, enzymatically inactivated and pasteurized) have been characterized in terms of their organoleptic quality. Quality parameters such as color (L, a, b values, Hue, Chroma, browning index, and anthocyanin content), taste (total soluble solids, acidity, sugars and organic acids profile), nutritional value (vitamin C and polyphenols contents) and aroma (volatile compounds) have been analyzed during 12 months of storage at 2°C and -18°C. Although quality changes showed quite different rates in whole fruits, purees, and concentrates, losses of anthocyanins and vitamin C were the most relevant changes observed during storage. In general, storage temperature had a greater effect on quality maintenance than processing temperature, particularly for anthocyanins and vitamin C contents. Thus, frozen non-pasteurized strawberry purees had significantly higher content of anthocyanins and vitamin C than refrigerated products, either previously submitted to thermal enzymatic inactivation and/or pasteurization, which lose 80% vitamin C and 40% anthocyanins after 3 months of storage. On the other hand, the quality standards of the fruits before processing seem to be critical for quality maintenance of the strawberry products.