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Knowledge about the timing of the aerobiological and phenological processes in plants with economic interest results of great agronomical importance, mainly for the establishment of the adaptive capacity of different varieties to various environmental conditions and the optimization of cultural practices. An agrometeorological study in two authorized varieties (Treixadura and Godello) of the Designation of Origin Ribeiro (North-western Spain) was conducted during the years 2008–2011. As consequence of the studied area bioclimatic conditions, the grapevine cycle exceed than 190 days and the varieties cultivated are considered as “late varieties.” The presence of Vitis pollen grains in the vineyard atmosphere was mainly registered during the stages 5 (inflorescence emerge) and 6 (flowering) which benefit a successful fertilization process. The variations in airborne pollen concentrations are related to temperature and humidity. Phenological models proposed in this paper offer a high accuracy as the standard deviation of error between estimated and observed values was low. The prediction variability ranges around 2 phenological scales in 2008 and 1 phenological scale in 2009, 2010 and 2011. These results indicate that the models developed to predict the phenology, in terms of degree days accumulated (GDD) using as a threshold temperature 10 °C, can be a useful tool to forecast the successive phenological events in the Designation of Origin Ribeiro area. During the stage 8 (ripening of berries), the GDD and the Brix Index were particularly correlated, so far as the differences between plants of the same variety are minimal.

In order to survive periods of adverse cold climatic conditions, plant requirements are satisfied by means of physiological adaptations to prevent cells from freezing. Thus, the growth of woody plants in temperate regions slows down and they enter into a physiological state called dormancy. In order to identify the chilling and heat requirements to overcome the dormancy period of Betula in the south of Europe, a comparative study was carried out with aerobiological pollen data of a 7-year (1995-2001) period in Vigo (Spain) and Perugia (Italy). To satisfy chilling requirements, base temperatures of 7 degrees C and 5.75 degrees C showed a lower standard variation coefficient: 3.94% and 2.36% in Perugia and Vigo respectively. In the case of heat accumulation, the sum of mean temperatures in Perugia and the sum of maximum temperatures in Vigo were the parameters that showed a minor coefficient of variation (11.13% and 14.51% respectively).

Although aerobiological data are often used in phenological research as an indicator of flowering, airborne pollen concentrations are influenced by a number of factors that could affect pollen curves. This paper reports on a study of various aspects of reproductive biology in Q. ilex subsp. ballota, together with environmental factors influencing pollen release and transport, with a view of achieving reliable interpretation of Quercus pollen curves in Ourense (NW Spain). Aerobiological data were recorded from 2002 to 2004 at two sites in the province of Ourense. From 1st February to the end of the flowering period, phenological observations were carried out on 19 trees from the Q. ilex subsp. ballota population found in the Ourense area. Pollen production was calculated for the same trees. The chilling and heating requirements for triggering development were also calculated. The mean flowering period lasted 11-15 days. Reduced pollen output per catkin and, especially, a reduced number of catkins per tree in 2003 and 2004, prompted a marked decline in overall pollen production. Major differences observed in Q. ilex subsp. ballota pollen curves were attributed to the considerable influence both of weather conditions during pollination and pollen production. In years with high pollen production and weather conditions favouring pollen release, Q. ilex subsp. ballota contributed almost 10% to the total Quercus pollen curve. Around 20% of the pollen trapped was captured before or after flowering periods.

The main crop of the A Limia region is the potato, with an average production of 5 million kilos per year, under the protected geographic indication (IGP) Pataca de Galicia (Galician potato) label recognized by the European Community. Alternaria represents an important part of the pathogenic fungus spectra on this crop, representing an average of 1.9-3.1% of the spores collected. It represents the fourth and third most common type, respectively, in the years of study, after the Cladosporium type (which represented 80% and 64% respectively in each year of study), the Basidia type (5.5% and 1.4%), Botrytis (3.5% and 1.3%), and Fusarium (2.7% and 25.2%). A Lanzoni VPPS 2000 Hirst volumetric sampler was placed in Damil, in the region of A Limia in order to determine the airborne concentration of Alternaria conidium over a potato crop and finally to try to establish the most suitable prediction models for Alternaria attacks and how they might be controlled. We applied different models based on temperature, such as the model of propitious days (P-Days), the model of accumulation of disfavourable days (DD), and the relative humidity model of interrupted wet periods (IWP). The most efficient model was found to be the interrupted wet periods (IWP) method as it could predict several days of attack during the development of the crop. It is efficient in A Limia even when the features described in this model are fulfilled during five consecutive days. In the first year of study the efficiency of this method was lower as alternariosis did not proliferate to the same degree due to the adverse meteorological conditions registered for the development of the fungus. This study is the first step towards prediction of infection by Alternaria in potato crops. We need more years of study in order to adjust these models to the conditions of the sampling area, and thus be able to confirm the necessary values and their suitability with the aim of developing possible alternatives to reduce the negative consequences of this pathogen.

This paper reviews the terms and major criteria used to define and limit the pollen season. Pollen data from Cordoba (Spain), Ourense (Spain) and Bologna (Italy) were used to ascertain the extent to which aerobiological results and pollen curves are modified by the criteria selected. Results were analysed using Spearmanȁ9s correlation test. Phenological observations were also used to determine synchronization between pollen curves and plant phenology. The criteria for limiting the shortest and longest pollen season periods, as well as the earliest and latest start and end dates, varied according to the city and the taxon under study; in many cases, results for a given taxon also depended on the year. The smallest differences were obtained for Platanus and the greatest for Poaceae.

Pollen forecasting models are a useful tool with which to predict episodes of type I allergenic risk and other environmental or biological processes. Parietaria is a wind-pollinated perennial herb that is responsible for many cases of severe pollinosis due to its high pollen production, the long persistence of the pollen grains in the atmosphere and the abundant presence of allergens in their cytoplasm and walls. The aim of this paper is to develop artificial neural networks (ANNs) to predict airborne Parietaria pollen concentrations in the northwestern part of Spain using a 19-year data set (1999–2017). The results show a significant increase in the length of time Parietaria pollen is in the air, as well as significant increases in the annual Parietaria pollen integral and mean daily maximum pollen value in the year. The Neural models show the ability to forecast airborne Parietaria pollen concentrations 1, 2, and 3 days ahead. A developed model with five input variables used to predict concentrations of airborne Parietaria pollen 1 day ahead shows determination coefficients between 0.618 and 0.652.

Aspergillus and Penicillium spores occur with considerable frequency in the outdoor air, and their presence is important due to implications in health, agriculture and biodeterioration of cultural heritage. The objective of this research was to study their abundance in the atmosphere of Havana from 2013 to 2017. Two study methods were used, viable method monitoring of the spores with Chirana Aeroscope equipment and the other a non-viable method Lanzoni VPPS 2000. The Aspergillus / Penicillium spores were found to occur with high frequency, their atmospheric concentration varied statistically between climatic seasons, the highest incidence was detected during 2013 and 2015. Aspergillus was more abundant (69%) than Penicillium (31%), with a predominance of the Flavi and Nigri sections, and for Penicillium predominated Penicillium and Furcatum . The viable method, 23 species of Aspergillus and 22 of Penicillium were identified, of which A. flavus , A. niger , P. aurantiogriseum and P. citrinum predominated. A greater degree of similarity was observed in the composition of Aspergillus species, with higher indices (Di,j 0.40-0.73) compared to Penicillium (Di,j 0.30-0.55). The principal component analysis (PCA) showed a high degree of positive association between Aspergillus / Penicillium and relative humidity (non-viable method) and between Aspergillus and Penicillium and maximum and average temperatures (viable method).

The most common fungal diseases of Vitis vinifera are powdery mildew ( Erysiphe necator (Schw.) Burr.), grey mould ( Botrytis cinerea Pers.) and downy mildew ( Plasmopara viticola (Berk. and Curt.) Berk. and de Toni). Knowledge about the concentration of their spores in the atmosphere of the vineyard is important in order to ascertain the fungal load in the vineyard during the reproductive vine cycle. An aerobiological study was conducted in three vineyards across Europe: in North-Western Spain (Cenlle), South Spain (Montilla) and South-Eastern Poland (Rzeszów). During 2016, three Hirst-type spore traps sampled the airborne particles in each vineyard during the reproductive cycle of grapevine. The main goal of this study was the analysis and comparison of the spore concentrations in the three studied viticultural areas using different statistical tools. The most abundant spores in the vineyards atmosphere were Erysiphe necator . The highest fungal spore concentrations belonged to the North-western Spain zone, due to rainfall and temperature conditions were optimal for mould development in this area. In South Spain and South-eastern Poland, the daily spore peaks took place before than North Spain spore peaks. Average temperature, relative humidity and rainfall were the principal factors affecting the spore concentration in all zones. Redundancy Analysis showed high correlation between meteorological parameters and fungal spore concentrations.

Olive is recognized as a crop with great impact in agricultural, socioeconomic, environmental and public health sectors. The last is becoming more important during recent years as consequence of the increase of the pollen allergy in south Europe prompted by the widespread Olea pollen allergic reactions. The aim of the study was to quantify, for the first time, the variations of the Ole e 1 allergen amount in Olea pollen grains from four cultivars in three regions of Portugal. How weather parameters can affect the allergen production was also assessed. The study was conducted in three olive producer areas of Portugal from 2010 to 2013, Santarém (Central), Elvas (Southeast) and Mirandela (Trás-os-Montes region, Northeast). Mature pollen of four different cultivars (Cobrançosa, Arbequina, Picual and Verdeal) was collected during the olive flowering season. Ole e 1 was quantified using specific 2-site antibody ELISA. Pollen of the olive groves at the boundary Olea bioclimatic distribution in the Mirandela registered the higher allergen content for all varieties in each study year. Arbequina was the variety that showed the lower Ole e 1 allergen concentration, whereas the higher content was registered for Cobrançosa. The main meteorological parameters that influenced the allergen Ole e 1 concentration in the pollen grains were the rainfall and temperatures related variables. The knowledge of the allergenicity in different olive cultivars is an important tool in the selection of the most adequate for planting as ornamental crop and to adjust the pollen extracts used for diagnosis or even immunotherapy.

The efficient evaluation of the potential pollen production of plants can provide preventive measures for the allergic population. For this purpose, a comparative study of three methods was carried out to evaluate pollen production (volumetric method, Neubauer chamber and Coulter cell counts), as well as other three methods to estimate pollen viability (fluorometry, colorimetry and germination) of Fraxinus . Our results indicate that the Neubauer chamber and the colorimetric response to two stains (acetic carmine with glycerol, ACG; 2, 3, 5-triphenyltetrazolium chloride, TTC) are the most adequate methods to determine, respectively, pollen production and quality, according to criteria of low cost, speed and reliability of the obtained data. Climate change is likely to influence vegetation, with consequent changes in growth and reproductive cycles, and therefore in pollen production. Considering the data obtained during the last two decades (1997–2017), we detected a statistically significant trend toward the increase in the airborne total annual pollen integral of Fraxinus pollen in NW Spain.