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Vespa velutina and V. crabro are eusocial insects in which chemical communication is decisive for social interactions. V. velutina was accidentally introduced in 2004 in France and subsequently in northern Spain in 2010. It is an invasive species that severely affects the beekeeping sector. The hornet autochthonous V. crabro with a similar ecological niche is captured in bait traps used to control V. velutina populations. Insect cuticle and head structures had an important role in chemical communication so that this research approaches for the first time chemical compounds extracted from the heads of V. velutina and V. crabro. Chemical compounds were profiled using GC/MS. The main compounds identified were carbohydrates, fatty acids, and hydrocarbons. The chemical profile of both species was compared and also an intrinsic differentiation was made between queens and workers in V. velutina. Chemometric techniques (PCA and LSD) were used to achieve this goal. [ABSTRACT FROM AUTHOR]

Potatoes production is the main source of income in A Limia (Northwest Spain). Most of the potatoes harvest is stored in piles in farmer´s warehouses without systems to control temperature and relative humidity and only a few industries have storage facilities with cooling systems. This study constitutes an approach to detecting fungal spores present inside potato warehouses and the influence of the environmental conditions on the prevalence of the different types of fungi. The most common spores were Cladosporium and Aspergillus/Penicillium representing more than 94% of the identified spores of fungi. However, some potential fungal potato pathogens such as Alternaria, Helminthosporium, Fusarium and Phytophthora were also detected. In the warehouse without control of the storage conditions, the most represented fungal spores were from Cladosporium followed by Aspergillus/Penicillium, Helminthosporium and Alternaria whereas during storage with cooling conditions, the most abundant were Aspergillus/Penicillium, Cladosporium, Fusarium, Helminthosporium and Leptosphaeria. The results showed a close relationship between the storage conditions and the levels of some identified fungi. The low representation of pathogenic fungi Alternaria and Helminthosporium stood out in the facilities with cooling systems. Monitoring of airborne elements during potato storage could be useful tool for detecting the presence of potato pathogens in the environment and taking management decisions to avoid economic losses. [ABSTRACT FROM AUTHOR]

Early blight caused mainly by Alternaria solani Soraeur and Alternaria alternata (Fr.) Keissl is one of the main diseases of potato. To improve forecasting of disease risk and to provide useful tools for a good decision support system, knowledge about the influence of environmental conditions on the Alternaria species, is necessary. The pattern distribution of the Alternaria spores during eight potato growing cycles in "A Limia" (north-west Spain), and the relationships between Alternaria levels and meteorological parameters were analyzed. Also, the phenology of the potato plants and the meteorological conditions during the study were monitored. Higher Alternaria peaks were found during plant senescence. Nevertheless, extremely high levels can appear starting the plant flowering, when the disease is more destructive. Statistical analysis showed a close relationship between temperature and relative humidity with the concentration of Alternaria in the air. Higher Alternaria levels were observed with a mean temperature above 20 °C and a mean relative humidity below 70%. It is also important to highlight that lower temperature and higher relative humidity during the night, favours the formation of Alternaria spores during the day. The present study showed how differences in weather can be related with the presence of Alternaria spores in the atmosphere of potato crop, and how climate change could affect the development of this agricultural crop. If Spain continues to experience increases in temperature events, longer duration and increasing intensity of early blight epidemics in potato crops are expected in future years. [ABSTRACT FROM AUTHOR]

The yellow-legged hornet, Vespa velutina, is a recent invasive species in Galicia (NW Spain). Its invasion has an important socio-economic impact because it preys upon honeybees (Apis mellifera) and other crucial insect pollinators. The dispersal of this species must be monitored to minimise the damage it causes and to take the necessary control actions. The aims of this study were to determine target and nontarget living organisms captured by bait trapping and to compare the distribution patterns of V. velutina and the autochthonous V. crabro. Altitude and weather conditions played important roles in hornet behaviour. The traps placed in low-altitude coastal areas contained the most yellow-legged hornets. In contrast, the autochthonous hornet occurred in relatively greater numbers in the traps hung in high-altitude areas. High minimum temperatures, dew temperature, relative humidity and low maximum temperatures favour the occurrence and spread of V. velutina. These conditions are common in the coastal areas of this territory and promoted the rapid dispersal of this pest. The traps used were not bait-selective, so many other arthropod organisms were captured along with the hornet. Therefore, the use of species-selective baits is required for the ecofriendly effective management of this insect pest. [ABSTRACT FROM AUTHOR]

Potatoes are one of the main foods throughout the world contributing to the daily intake of nutrients. This work studies the relationship among some physical characteristics of tubers from 35 potato varieties, the total phenol and flavonoid content and their antioxidant potential. Some significant differences were found depending on the potato variety. Thus, Fleur Bleue, Violetta, Yona, Stronga and Flamenco tubers had the highest antioxidant capacity. This is apparently a consequence of the presence of purple and red pigments in skin and flesh. A regression model for radical scavenging activity, total phenol content and the value of coordinate a* (CIElab scale) for tuber flesh was obtained. [ABSTRACT FROM AUTHOR]

Potato is one of the main agricultural crops in north-western Spain. Varieties such as Baraka, Kennebec, Desiree and Alava are more commonly planted, but there is an interest in introducing other improved cultivars. The first step in the identification of a new potato varieties includes an assessment of the morphological characteristics of its aerial parts and their tubers characteristics. In this work, 36 botanical descriptors of 28 potato varieties were studied. The study took place during 2014 and 2015 in an experimental field at the Agricultural Research Centre of INORDE in A Limia (Ourense), Spain. Each variety was planted in three plots distributed within the experimental field. Morphological characteristics were measured on six plants of each variety. Multivariate statistical analyses were performed to identify differences and similarities between varieties. The floral characteristics and the degree of flowering were important features to differentiate the varieties. Also, plant habit, pigmentation in stem, calix and pedicel contributed to this differentiation. [ABSTRACT FROM AUTHOR]

lternaria solani Soraeur produces early blight in Solanum tuberosum L., leading to significant agricultural losses. The current study was carried out on the extensive potato crop situated in north-western of Spain during 2007, 2008 and 2009. In this area potato crops are the most important source of income. In this work we used a Hirst-type volumetric spore-trap for the aerobiological monitoring of Alternaria spores. The highest spore concentrations were recorded during the 2009 cycle (10,555 spores), and the lowest concentrations were recorded during the 2008 cycle (5,471 spores). Over the 3 years of study, the highest concentrations were registered during the last stage of the crop. The aim of the study was to observe the influence of meteorological factors on the concentration of Alternaria spores, which can lead to serious infection and early blight. Prediction of the stages during which a crop is particularly vulnerable to infection allows for adjustment of the application of fungicide and is of environmental and agricultural importance. For this reason, we tested three models (P-Days, DD and IWP) to predict the first treatment and decrease the negative effect that these spores have on potato crops. The parameter that showed the most significant correlation with spore concentrations was minimum temperature. We used ARIMA (autoregressive integrated model of running mean) time-series models to determine the forecast. We considered weather data as predictor variables and the concentration of spores on the previous day as the fixed variable. [ABSTRACT FROM AUTHOR]

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