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.

中文翻译：

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西班牙西北部马铃薯生长周期中链格孢的季节性变化以及天气对早疫病的影响

主要由马铃薯链格孢和链格孢引起的早疫病Keissl是马铃薯的主要病害之一。为了改善疾病风险的预测并为良好的决策支持系统提供有用的工具，必须了解环境条件对链格孢菌种的影响。分析了“ A Limia”（西班牙西北部）八个马铃薯生长周期中的链格孢菌孢子分布，并分析了链格孢菌水平与气象参数之间的关系。此外，还监测了马铃薯植株的物候和研究过程中的气象条件。高链念珠菌在植物衰老过程中发现了峰值。然而，当病害更具破坏性时，可能会出现极高水平的植物开始开花。统计分析表明温度和相对湿度与空气中链格孢菌的浓度密切相关。平均温度高于20°C，平均相对湿度低于70％，观察到较高的链格孢菌水平。同样重要的是要强调夜间较低的温度和较高的相对湿度有利于白天形成链格孢菌孢子。本研究表明天气差异如何与链格孢菌的存在有关马铃薯作物大气中的孢子，以及气候变化如何影响这种农作物的生长。如果西班牙继续经历温度升高的事件，那么预计未来几年马铃薯作物的病害持续时间会更长，早期疫病流行的强度也会增加。