Climatic drivers of Verticillium dahliae occurrence in Mediterranean olive-growing areas of southern Spain Requena-Mullor, Juan M. García Garrido, José Manuel García López, Pedro Antonio Rodríguez Navarro, Estefanía We would like to thank farmers from Granada province for kindly permitting us to research their olive groves. We also wish to give special thanks to Mr. Antonio Leo´n, chief executive officer of Caja Rural in Granada, for encouraging this research and Toby Wakely for reviewing this manuscript in English. Data Availability Statement: All data are available from the GitHub repository (https://github.com/ jmrmcode/Verticillium-wilt-Dataset.git). Verticillium wilt, caused by the soil-borne fungus Verticillium dahliae, is one of the most harmful diseases in Mediterranean olive-growing areas. Although, the effects of both soil temperature and moisture on V. dahliae are well known, there is scant knowledge about what climatic drivers affect the occurrence of the pathogen on a large scale. Here, we investigate what climatic drivers determine V. dahliae occurrence in olive-growing areas in southern Spain. In order to bridge this gap in knowledge, a large-scale field survey was carried out to collect data on the occurrence of V. dahliae in 779 olive groves in Granada province. Forty models based on competing combinations of climatic variables were fitted and evaluated using information-theoretic methods. A model that included a multiplicative combination of seasonal and extreme climatic variables was found to be the most viable one. Isothermality and the seasonal distribution of precipitation were the most important variables influencing the occurrence of the pathogen. The isothermal effect was in turn modulated by the seasonality of rainfall, and this became less negative as seasonality increases. Thus, V. dahliae occurs more frequently in olive-growing areas where the day-night temperature oscillation is lower than the summer-winter one. We also found that irrigation reduced the influence of isothermality on occurrence. Our results demonstrate that long-term compound climatic factors rather than “primary” variables, such as annual trends, can better explain the spatial patterns of V. dahliae occurrence in Mediterranean, southern Spain. One important implication of our study is that appropriate irrigation management, when temperature oscillation approaches optimal conditions for V. dahliae to thrive, may reduce the appearance of symptoms in olive trees. 2021-03-03T08:06:52Z 2021-03-03T08:06:52Z 2020-12-30 info:eu-repo/semantics/article Requena-Mullor JM, García-Garrido JM, García PA, Rodríguez E (2020) Climatic drivers of Verticillium dahliae occurrence in Mediterranean olive-growing areas of southern Spain. PLoS ONE 15(12): e0232648. [https://doi.org/10.1371/journal.pone.0232648] http://hdl.handle.net/10481/66794 10.1371/journal.pone.0232648 eng http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Atribución 3.0 España Public Library of Science