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This paper provides an updated of airborne Alternaria spore spatial and temporal distribution patterns in the Iberian Peninsula, using a common non-viable volumetric sampling method. The highest mean annual spore counts were recorded in Sevilla (39,418 spores), Mérida (33,744) and Málaga (12,947), while other sampling stations never exceeded 5,000. The same cities also recorded the highest mean daily spore counts (Sevilla 109 spores m(-3); Mérida 53 spores m(-3) and Málaga 35 spores m(-3)) and the highest number of days on which counts exceeded the threshold levels required to trigger allergy symptoms (Sevilla 38 % and Mérida 30 % of days). Analysis of annual spore distribution patterns revealed either one or two peaks, depending on the location and prevailing climate of sampling stations. For all stations, average temperature was the weather parameter displaying the strongest positive correlation with airborne spore counts, whilst negative correlations were found for rainfall and relative humidity.

The present work studies the seasonal variation of Phytophthora infestans concentrations in the atmosphere of a potato crop grown in A Limia. Different models have also been tested to predict the attack of this pathogen in order to establish the necessary treatments. Sampling has been carried out during crop cycles in 2004, 2005 and 2007 by using a volumetric spore trap, located in the centre of the plot at a height of 1.5 m. The collection of meteorological data was done with an automatic gauge. The highest concentrations of Phytophthora infestans were registered during June and July, with maximum daily levels ranging from 82 to 145 spores/m 3 , as a result of the maximum temperature average, around 16-23°C. Three prediction models for Phytophthora infestans have been adjusted to our area of study. The Smith Periods model provides better results in years with low and medium levels of the oomycete inoculum. The NegFRY model is useful to adjust the day of first treatment application, when used together with the Negative Prognosis model. To observe the influence of meteorological parameters on Phytophthora infestans spore concentration, besides applying these models, a Spearman correlation analysis was carried out. This test allowed the establishment of a correlation between the temperature parameter and the oomycete, obtaining positive and significant correlations (p<0.01).Resumen El presente trabajo estudia la variación temporal de las concentraciones de Phytophthora infestans en la atmósfera de un cultivo de patata en A Limia. Se han probado también diferentes modelos para predecir el ataque de este patógeno a fin de establecer los tratamientos necesarios. Se tomaron muestras durante los ciclos de cultivo en 2004, 2005, y 2007 mediante el uso de un captador volumétrico de esporas, ubicada en el centro la finca a una altura de 1.5 metros. Los datos meteorológicos se tomaron con una estación automática. Se registraron las concentraciones más altas de Phytophthora infestans durante junio y julio, con niveles diarios máximos fluctuando de 82 a 145 esporas/m 3 , como resultado del promedio máximo de temperatura, alrededor de 16-23°C. Se ajustaron tres modelos predictivos para Phytophthora infestans en nuestra área de estudio. El modelo de períodos Smith da mejores resultados en años con niveles bajos y medios de inóculo del oomycete. El modelo NegFRY es útil para ajustar el día de la aplicación del primer tratamiento, cuando se usa junto con el modelo de Prognosis Negativa. Además de aplicar estos modelos, se efectuó un análisis de correlación de Spearman, para observar la influencia de los parámetros meteorológicos en la concentración de esporas de Phytophthora infestans. Esta prueba permitió el establecimiento de una correlación entre la temperatura y el oomycete, obteniéndose correlaciones positivas y significativas (p<0.01).

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