Indications of strong adaptive population genetic structure in albacore tuna (Thunnus alalunga) in the southwest and central Pacific Ocean

Albacore tuna (Thunnus alalunga) has a distinctly complex life history in which juveniles and adults separate geographically but at times inhabit the same spaces sequentially. The species also migrates long distances and presumably experiences varied regimes of physical stress over a lifetime. There are, therefore, many opportunities for population structure to arise based on stochastic differences or environmental factors that promote local adaptation. However, with the extent of mobility consistently demonstrated by tagged individuals, there is also a strong argument for panmixia within an ocean basin. It is important to confirm such assumptions from a population genetics standpoint for this species in particular because albacore is one of the principal market tuna species that sustains massive global fisheries and yet is also a slow‐growing temperate tuna. Consequently, we used 1,837 neutral SNP loci and 89 loci under potential selection to analyze population genetic structure among five sample groups collected from the western and central South Pacific. We found no evidence to challenge panmixia at neutral loci, but strong indications of structuring at adaptive loci. One population sample, from French Polynesia in 2004, was particularly differentiated. Unfortunately, the current study cannot infer whether the divergence is geographic or temporal, or possibly caused by sample distribution. We encourage future studies to include potentially adaptive loci and to continue fine scale observations within an ocean basin, and not to assume genome‐wide panmixia

Strawberry cultivar and breeding lines susceptibility to Phytophthora crown and root rot in Huelva (Spain)

4 Páginas, 1 FiguraPhytophthora crown and root rot of strawberries is caused by Phytophthora cactorum. Breeding programs for resistance to this disease are in progress in Spain. In a previous work, the different susceptibility of the most important strawberry cultivars used in Huelva (Spain) was observed. In the present work, 2 cultivars and 3 breeding lines were included in assays of susceptibility with artificial inoculation. Eighteen plants of each cultivar were inoculated with a root bath in a suspension with P. cactorum propagules. After inoculation, plants were cultivated in a growth chamber in a randomized design with three repetitions of six plants each. The assays were conducted two times from September to December in 2014 and 2015. Results showed 4 susceptibility groups: 'Fortuna' the most susceptible cultivar; 'Primoris' with moderate susceptibility; 'A11-407P-3' and 'A10-48-3' with lower susceptibility and 'A10-207P-8' the lowest susceptible breeding line. 'A10-207P-8' had 56.4% less disease severity than the most susceptible cultivar. Therefore, the use of these three breeding lines will be an interesting resource to control this disease in an integrated disease management program.This research was supported by grants from Corporación Tecnológica de Andalucía (CTA: 12/633). We thank S. Castillo, A. Gata and S. Pérez for excellent technical assistance.Peer reviewe

Strawberry postharvest shelf life is related to total acid content and fruit firmness

Strawberry fruit has a short postharvest shelf life because it is very perishable and susceptible to several pathogens that quickly reduce the quality of the fruit. A large part of Huelva's strawberry production is exported, so the shelf life of the fruit is one of the main factors that determines the quality of the fruit when it reaches its destination. The aim of this work was to explore the relationship between postharvest shelf life and the agronomic and quality traits in different strawberry genotypes during several seasons. For this, the postharvest shelf life, early and total yield, soluble solids content, fruit firmness and the content of sugars and organic acids were quantified during four consecutive seasons (2016-2019). First, the relationships of the shelf life with the other variables were explored through a principal components analysis (PCA). Subsequently, the variables that showed a stronger association with the shelf life were analysed in more detail by correlation and linear regression analysis. The PCA showed a positive relationship of the shelf life with the acid content and with fruit firmness measured with penetrometer and subjectively. Specifically, the correlation between the shelf life and firmness (measured with a penetrometer and subjectively) and the total acid was 0.59, 0.48 and 0.53, respectively. In conclusion, the variables of firmness and acid content can be useful to select genotypes in a strawberry breeding program with an increased shelf life.Peer reviewe

Relationship between sugar content and °Brix as influenced by cultivar and ripening stages of strawberry

8 Páginas, 2 Figuras, 1 TablasWe have evaluated eight cultivars of strawberry, seven short-day and one day-neutral, for two years with two sampling dates and two repetitions by date to assess the relationship between sugar content and degree Brix. The fruits were collected and evaluated at the ripe stage. Contents of sucrose, glucose, fructose, °Brix, citric acid, ascorbic acid and malic acid in the fruit were measured. The data were analyzed using principal component analysis (PCA) and Pearson correlations. The PCA groups most of the variability in the first component (62.2%). This component shows a positive relationship between the Brix degrees, sugars and acids (higher values of this component indicate increased Brix degrees, and the contents of sugars and acids). The second component collects 20.74% of the variability, which is mainly related to differences in the sugars/acids ratio. The plotting of the factor barycenter over the two principal components of PCA analysis shows that second harvest date has a higher content of sugars, organic acids and °Brix. With regard to cultivars representation over PCA, the good quality cultivar 'Primoris' is characterized by a high sugar content and a balanced total sugars/acids ratio. Moreover, the day-neutral cultivar 'Nieva' shows the lowest values of sugars, acids, °Brix and total sugars/acids ratio. Featured correlations exist between ascorbic acid content and glucose and fructose content (R2=0.82 and 0.81, respectively). The °Brix shows a relative correlation with the total sugars content (R2=0.74). In conclusion, the genotype has large effect in the content of sugars and organic acids. Therefore, the high content of sugars and acids and a balanced relationship between them could be used as a quality trait for the selection of strawberry varieties. On the other hand, °Brix is a relative good measure of the total sugar content.Fernando Pistón is partially supported by the Torres Quevedo Programme, which is managed by Ministerio de Agricultura, Alimentación y Medio of the Spanish GovernmentPeer reviewe

A10-48-3 and A7-32-10, two strawberry selections with well-balanced nutritional and organoleptic quality

10 Páginas; 3 Figuras; 2 TablasIn the last few years organoleptic and nutritional traits have become the major breeding targets in most strawberry breeding programs all over the world. Furthermore, the joint improvement of the nutritional value and the sensory key parameters of strawberry might increase the consumption rate of this fruit, which in turn will have a positive effect on consumer's health and a positive economic impact on the producing areas. New cultivars and strawberry selections bred in Huelva (southwestern Spain) have been characterized in relation to their organoleptic and nutritional properties. Key metabolites associated to the strawberry flavor (sucrose, fructose, glucose, malic and citric acid and 20 main volatile compounds) as well as specific phytochemicals (nine phenolic compounds plus vitamin C) with relevant antioxidant capacities have been analyzed by high resolution gas chromatography coupled to mass spectrometry (HRGC-MS) and high performance liquid chromatography (HPLC). Data were analyzed using principal component analysis (PCA) and Pearson correlations to discriminate those strawberry selections that, besides good agronomic performances, produce fruits with high contents of key flavor components and health-promoting phytochemicals. PCA clearly distinguish selections A10-48-3 and A7-32-10 as having significantly different metabolic profiles and displaying the highest contents of sugars, organic acids, ethyl esters, mesifurane, terpineol, quercetin and vitamin C.We are grateful to Mar Pascual for her excellent technical assistance. This work was supported by research project Recupera 2020 financed by MINECO-CSIC with FEDER funding.Peer reviewe

Moss cover and browsing scores as sustainability indicators of mountain ungulate populations in Mediterranean environments

Here, we aimed to define ecological indicators of environmental change for monitoring the effect of a reintroduced species, the Iberian ibex (Capra pyrenaica), over the vegetation of a natural protected area with contrasting habitats. This species was reintroduced 30 years ago in the Sierra de Guadarrama National Park, Spain, and its population has since grown exponentially, reaching high densities in some areas. We tested the suitability of two complementary indicators: browsing damage on woody species and the percentage of moss cover loss on rocky outcrops. For this purpose, we used a mathematical approach to zone the natural protected area according to the historical presence of the species and established five different Iberian ibex pressure classes (Classes I–V). Our results showed a direct link between Iberian ibex pressure and vegetation status. Model predictions suggested 10% moss loss in the areas with low pressure (Class I) but 64% loss in the areas with high pressure (Class III), mostly due to ungulate trampling on rocks. Similarly, browsing damage increased with increasing pressure classes for different woody species. Low palatable plant species such as Pinus spp. showed little change in browsing damage for increasing ungulate pressure whereas more palatable plants (e.g., Erica arborea) showed significantly greater browsing damage variation across pressure classes (i.e., high sensitive to herbivory pressure). Both, moss cover on rocks and widely distributed palatable woody plants proved useful ecological indicators for monitoring ungulate populations in mountainous areas with a diverse array of habitats (e.g., rocky vs. woody). This methodology may help select the most suitable indicators for each type of ecosystem or dominant habitat in ungulate-dominated ecosystems.En este trabajo se pretende definir indicadores ecológicos de cambio ambiental para monitorizar el efecto de una especie reintroducida, la cabra montés (Capra pyrenaica), sobre la vegetación de un espacio natural protegido. Esta especie fue reintroducida hace 30 años en el Parque Nacional de la Sierra de Guadarrama, España, y desde entonces su población ha crecido exponencialmente, alcanzando altas densidades en algunas zonas. Se comprobó la idoneidad de dos indicadores complementarios: los daños por ramoneo en especies leñosas y el porcentaje de pérdida de cobertura de musgo en afloramientos rocosos. Para ello, utilizamos una aproximación matemática para zonificar el espacio natural protegido en función de la presencia histórica de la especie y establecimos cinco clases diferentes de presión de la cabra montés ibérica (Clases I-V). Nuestros resultados mostraron una relación directa entre la presión de la cabra montés y el estado de la vegetación. Las predicciones del modelo sugerían una pérdida de musgo del 10% en las zonas con baja presión (Clase I) pero del 64% en las zonas con alta presión (Clase III), debido principalmente al pisoteo de rocas por parte de los ungulados. Del mismo modo, los daños causados por el ramoneo aumentaron con el incremento de las clases de presión para las diferentes especies leñosas. Las especies vegetales poco palatables, como Pinus spp., mostraron pocos cambios en los daños por ramoneo al aumentar la presión de los ungulados, mientras que las plantas más palatables (por ejemplo, Erica arborea) mostraron una variación significativamente mayor de los daños por ramoneo entre las clases de presión (es decir, alta sensibilidad a la presión herbívora). Tanto la cobertura de musgo en las rocas como las plantas leñosas palatables ampliamente distribuidas resultaron ser indicadores ecológicos útiles para el seguimiento de las poblaciones de ungulados en zonas montañosas con una gran diversidad de hábitats (por ejemplo, rocosos frente a leñosos). Esta metodología puede ayudar a seleccionar los indicadores más adecuados para cada tipo de ecosistema o hábitat dominante en ecosistemas dominados por unguladosComunidad de MadridMinisterio de UniversidadesUnión Europea (EU)Ministerio de Ciencia e Innovación (MICIN)Universidad Politécnica de Madrid (UPMDepto. de Biodiversidad, Ecología y EvoluciónFac. de Ciencias BiológicasTRUEpu

COVID-19 Confinement Effects on Game Actions during Competition Restart in Professional Soccer Players

The main objective of the present study was to compare high-intensity actions in a week of three matches before and after the COVID-19 lockdown. The observational methodology was used. This study analysed 551 professional soccer players from 22 different Spanish teams (LaLiga Smartbank 2019–2020) by a multi-camera tracking system and associated software (Mediacoach®, Spain). Variables of distances per minute and totals, travelled at High Intensity (HIR), Very High Intensity (VHIR), Sprint (HSR), player’s maximum speed, average speed, and the number of efforts in VHIR and HSR were analysed in the first and second half of the games, the full match, as well as in relation to the playing position. Players who participated in the same number of matches pre- and post-COVID-19 showed an increase in the total minutes played, p < 0.05, and small decreases in game actions, p < 0.05, with an effect size between 0.21 and 0.45, while players who participated in different number of matches pre- and post-COVID-19 showed a performance decrease, p < 0.05, with a size effect between 0.13 and 0.51; this was evident, particularly, for midfielders, p < 0.05, with a size effect between 0.39 and 0.75. The results seem to show that the playing intensity after COVID-19 confinement did not lead to large performance losses, except for midfielders who were the most involved players and showed a higher decrease in performance. The main findings of this study could provide insight to football coaches for rotations in starting line-ups and game substitutions, so as not to affect the intensity levels of the competitions