Phytophthora infestans Prediction for a Potato Crop

Abstract

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).

Spatiotemporal variation in airborne sporangia of Phytophthora infestans: characterization and initiatives towards improving potato late blight risk estimation

“…Also, there was a weak correlation between the ASC and selected weather parameters (Table 1). These results differ from those reported by Iglesias et al (2010), who found a significant correlation between ASC of P. infestans and meteorological factors. Therefore, it is reasonable to suggest the hypothesis that early in the season, most sporangia captured at a height of 3 m were attributable to long-distance transport (incoming sporangia or off-farm inoculum sources).…”

Interrupted Wet Period (IWP) to Forecast the Aerial Alternaria in Potato Crops of A Limia (Spain)

“…Forecasting the risk of infection by a pathogen in cultivars is indispensable for the correct management of agricultural crops [18]. The susceptibility of the cultivars, the presence of primary inoculum, and the variations in disease sensitivity depending on environmental conditions are fundamental factors for improvement in fungal control [18,[34][35][36]. In recent years, diverse modelling approaches such as control strategies for the prediction of fungal diseases have been proposed.…”

Aerobiological monitoring of Aspergillus/Penicillium spores during the potato storage

“…Many studies have shown that the concentration of fungal spores in indoor and outdoor air is strongly related to meteorological factors (Burch and Levetin 2002;Sakiyan and Inceoglu 2003;Sen and Asan 2009;Iglesias et al 2010;Escuredo et al 2011). The two storage periods studied with higher number of spores counted (2002/2003 and 2007/2008) coincided with the higher mean temperature of all the period, and this relation has been seen in the main peaks recorded.…”

“…The majority of these studies focused on predicting the airborne fungal spores circulating in the air (GrinnGofron and Strzelczak 2008;Iglesias et al 2010;Escuredo et al 2011). Since weather is one of the most important factors influencing the development of fungus, these models were based on the weather.…”