Assessment of the effects of ozone exposure and plant competition on the reproductive ability of three therophytic clover species from Iberian pastures

Ozone (O3) phytototoxicity has been reported on a wide range of crops and wild Central European plantspecies, however no information has been provided regarding the sensitivity of plantspecies from dehesa Mediterranean therophytic grasslands in spite of their great plantspecies richness and the high O3 levels that are recorded in this area. A study was carried out in open-top chambers (OTCs) to assess the effects of O3 and competition on the reproductiveability of threecloverspecies: Trifolium cherleri, Trifolium subterraneum and Trifolium striatum. A phytometer approach was followed, therefore plants of these species were grown in mesoscosms composed of monocultures of four plants of each species, of threeplants of each species competing against a Briza maxima individual or of a single plant of each cloverspecies competing with threeB. maximaplants. Three O3 treatments were adopted: charcoal filtered air (CFA), non-filtered air (NFA) and non-filtered air supplemented with 40 nl l−1 of O3 (NFA+). The different mesocosms were exposed to the different O3 treatments for 45 days and then they remained in the open. Ozoneexposure caused reductions in the flower biomass of the threecloverspecies assessed. In the case of T. cherleri and T. subterraneum this effect was found following their exposure to the different O3 treatments during their vegetative period. An attenuation of these effects was found when the plants remained in the open. Ozone-induced detrimental effects on the seed output of T. striatum were also observed. The flower biomass of the cloverplants grown in monocultures was greater than when competing with one or threeB. maxima individuals. An increased flower biomass was found in the CFA monoculture mesocosms of T. cherleri when compared with the remaining mesocosms, once the plants were exposed in the open for 60 days. The implications of these effects on the performance of dehesa acid grasslands and for the definition of O3 critical levels is discussed

Fenología y capacidad de dispersión de Monochamus galloprovincialis (Olivier 1795) en la Península Ibérica = Phenology and dispersal ability of Monochamus galloprovincialis (Olivier 1795) at Iberian Peninsula

La aparición y avance de la enfermedad del marchitamiento del pino (Pine Wilt Desease, PWD), causada por Bursaphelenchus xylophilus (Nematoda; Aphelenchoididae), el nematodo de la madera del pino (NMP), en el suroeste de Europa, ha puesto de manifiesto la necesidad de estudiar la fenología y la dispersión de su único vector conocido en Europa, Monochamus galloprovincialis (Col., Cerambycidae). El análisis de 12 series de emergencias entre 2010 y 2014, registradas en Palencia, València y Teruel, con material procedente de diversos puntos de la península ibérica, demostró una alta variabilidad en la fenología de M. galloprovincialis y la divergencia térmica respecto de las poblaciones portuguesas. Para éstas, el establecimiento de los umbrales térmicos de desarrollo de las larvas post-dormantes del vector (12,2 y 33,5ºC) permitió la predicción de la emergencia mediana para la fecha en la que se acumulaban de 822 grados-día. Ninguna de las series analizadas en este trabajo necesitó de dichos grados-día estimados para la emergencia mediana. Asimismo, la emergencia se adelantó en las regiones más calurosas, mientras que se retrasó en las zonas más templadas. Más allá de la posible variabilidad entre poblaciones locales peninsulares, se detectaron indicios de que la diferencia en la acumulación de calor durante el otoño puede afectar el grado de maduración de las larvas invernantes, y su posterior patrón temporal de emergencia. Por último, también fueron observados comportamientos de protandria en las emergencias. Respecto a la fenología de su vuelo, entre los años 2010 y 2015, fueron ejecutados un total de 8 experimentos de captura de M. galloprovincialis mediante trampas cebadas con atrayentes en diferentes regiones (Castellón, Teruel, Segovia y Alicante) permitiendo el seguimiento del periodo de vuelo. Su análisis permitió constatar la disminución de las capturas y el acortamiento del periodo de vuelo con la altitud, el inicio del vuelo en el mes de mayo/junio a partir de los 14ºC de temperatura media diaria, la influencia de las altas temperaturas en la disminución de las capturas estivales (potencial causante de perfiles bimodales en las curvas de vuelo en las zonas menos frías), la evolución de la proporción de sexos a lo largo del periodo de vuelo (que muestra una mayor captura de hembras al inicio y de machos al final) y el comportamiento diurno y ligado a las altas temperaturas del vuelo circadiano del insecto. Dos redes de muestreo sistemático de insectos saproxílicos instaladas en la Comunitat Valencia (Red MUFFET, 15 parcelas, año 2013) y en Murcia (Red ESFP, 20 parcelas, años 2008-2010) permitieron el estudio de la comunidad de insectos relacionada con M. galloprovincialis. Cada una de las parcelas contaba con una trampa cebada con atrayentes y una estación meteorológica. El registro de más de 250 especies de coleópteros saproxílicos demostró el potencial que tiene el empleo de redes de trampas vigía para la detección temprana de organismos exóticos, además de permitir la caracterización y evaluación de las comunidades de entomofauna útil, representando una de las mejores herramientas de la gestión integrada de plagas. En este caso, la comunidad de saproxílicos estudiada mostró ser muy homogénea respecto a la variación ambiental de las zonas de muestreo, y que pese a las pequeñas variaciones entre las comunidades de los diferentes ecosistemas, el rol que M. galloprovincialis desempeña en ellas a lo largo de todo el gradiente estudiado es el mismo. Con todo, el análisis mediante redes de interacción mostró su relevancia ecológica al actuar de conector entre los diferentes niveles tróficos. Por último, un total de 12 experimentos de marcaje-liberación-recaptura desarrollados entre 2009 y 2012 en Castellón, Teruel, Valencia y Murcia permitieron evaluar el comportamiento dispersivo de M. galloprovincialis. Las detecciones mediante trampas cebadas de los insectos liberados se dieron por lo menos 8 días después de la emergencia. La abundancia de población pareció relacionada con la continuidad, la naturalización de la masa, y con la afección previa de incendios. La dispersión no estuvo influida por la dirección ni la intensidad de los vientos dominantes. La abundancia de material hospedante (en lo referente a las variables de masa y a los índices de competencia) influyó en la captura del insecto en paisajes fragmentados, aunque la ubicación de las trampas optimizó el número de capturas cuando se ubicaron en el límite de la masa y en zonas visibles. Por último también se constató que M. galloprovincialis posee suficiente capacidad de dispersión como para recorrer hasta 1500 m/día, llegando a alcanzar distancias máximas de 13600m o de 22100 m. ABSTRACT The detection and expansion of the Pine Wilt Desease (PWD), caused by Bursaphelenchus xylophilus (Nematoda; Aphelenchoididae), Pine Wood Nematode (PWN), in southwestern Europe since 1999, has triggered off the study of the phenology and the dispersion of its unique vector in the continent, Monochamus galloprovincialis (Coleoptera, Cerambycidae). The analysis of 12 emergence series between 2010 and 2014 registered in Palencia, Teruel and Valencia (Spain), registered from field colonized material collected at several locations of the Iberian Peninsula, showed a high variability in the emergence phenology of M. galloprovincialis. In addition, these patterns showed a very acute thermal divergence regarding a development model fitted earlier in Portugal. Such model forecasted the emergence of 50% of M. galloprovincialis individuals in the Setúbal Peninsula (Portugal) when an average of 822 degree-days (DD) were reached, based on the accumulation of heat from the 1st of March until emergence and lower and upper thresholds of 12.2 ºC and 33,5 °C respectively. In our results, all analyzed series needed less than 822 DD to complete the 50% of the emergence. Also, emergency occurred earlier in the hottest regions, while it was delayed in more temperate areas. Beyond the possible variability between local populations, the difference in the heat accumulation during the fall season may have affected the degree of maturation of overwintering larvae, and subsequently, the temporal pattern of M. galloprovincialis emergences. Therefore these results suggest the need to differentiate local management strategies for the PWN vector, depending on the location, and the climatic variables of each region. Finally, protandrous emergence patterns were observed for M. galloprovincialis in most of the studied data-sets. Regarding the flight phenology of M. galloprovincialis, a total of 8 trapping experiments were carried out in different regions of the Iberian Peninsula (Castellón, Teruel, Segovia and Alicante) between 2010 and 2015. The use of commercial lures and traps allowed monitoring of the flight period of M. galloprovincialis. The analyses of such curves, helped confirming different aspects. First, a decline in the number of catches and a shortening of the flight period was observed as the altitude increased. Flight period was recorded to start in May / June when the daily average temperature went over 14 ° C. A significant influence of high temperatures on the decrease of catches in the summer was found in many occasions, which frequently lead to a bimodal profile of the flight curves in warm areas. The evolution of sex ratio along the flight period shows a greater capture of females at the beginning of the period, and of males at the end. In addition, the circadian response of M. galloprovincialis to lured traps was described for the first time, concluding that the insect is diurnal and that such response is linked to high temperatures. Two networks of systematic sampling of saproxylic insects were installed in the Region of Valencia (Red MUFFET, 15 plots, 2013) and Murcia (Red ICPF, 20 plots, 2008-2010). These networks, intended to serve the double purpose of early-detection and long term monitoring of the saproxylic beetle assemblies, allowed the study of insect communities related to M. galloprovincialis. Each of the plots had a trap baited with attractants and a weather station. The registration of almost 300 species of saproxylic beetles demonstrated the potential use of such trapping networks for the early detection of exotic organisms, while at the same time allows the characterization and evaluation of useful entomological fauna communities, representing one of the best tools for the integrated pest management. In this particular case, the studied community of saproxylic beetles was very homogeneous with respect to environmental variation of the sampling areas, and despite small variations between communities of different ecosystems, the role that M. galloprovincialis apparently plays in them across the studied gradient seems to be the same. However, the analysis through food-webs showed the ecological significance of M. galloprovincialis as a connector between different trophic levels. Finally, 12 mark-release-recapture experiments were carried out between 2009 and 2012 in Castellón, Teruel, Valencia and Murcia (Spain) with the aim to describe the dispersive behavior of M. galloprovincialis as well as the stand and landscape characteristics that could influence its abundance and dispersal. No insects younger than 8 days were caught in lured traps. Population abundance estimates from mark-release-recapture data, seemed related to forest continuity, naturalization, and to prior presence of forest fires. On the other hand, M. galloprovincialis dispersal was not found to be significantly influenced by the direction and intensity of prevailing winds. The abundance of host material, very related to stand characteristics and spacing indexes, influenced the insect abundance in fragmented landscapes. In addition, the location of the traps optimized the number of catches when they were placed in the edge of the forest stands and in visible positions. Finally it was also found that M. galloprovincialis is able to fly up to 1500 m / day, reaching maximum distances of up to 13600 m or 22100 m.

Co-aggregation ability of cell Wall components of Saccharomyces cerevisiae to pathogenic bacteria

Autoaggregation in bacteria is the phenomenon of aggregation between cells of the same strain, whereas coaggregation is due to aggregation occurring among different species. Aggregation ability of prebiotic bacteria is related to adhesion ability, which is a prerequisite for the colonization and protection of the gastrointestinal tract in all animal species; however, coaggregation ability of prebiotic bacteria offers a possibility of close interaction with pathogenic bacteria.