1. Climate change effects on leaf rust of wheat: Implementing a coupled crop-disease model in a French regional application
- Author
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Dominique Ripoche, Marie Odile Bancal, Marie Launay, David Gouache, Frédéric Huard, Samuel Buis, Julie Caubel, Laurent Huber, François Brun, Instituts techniques agricoles (ACTA), UE Agroclim (UE AGROCLIM), Institut National de la Recherche Agronomique (INRA), ARVALIS - Institut du végétal [Paris], Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes (EMMAH), Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, MICMAC Design project, ANR-09-STRA-06 and the ACCAF-CLIF project (Climate change and fungal diseases), and Agroclim (AGROCLIM)
- Subjects
0106 biological sciences ,Canopy ,STICS soil-crop model ,maladie foliaire ,sporulation ,[SDE.MCG]Environmental Sciences/Global Changes ,Microclimate ,Soil Science ,Climate change ,Context (language use) ,Plant Science ,Biology ,01 natural sciences ,Rust ,MILA model ,high temperature ,Crop ,Effects of global warming ,modèle sol culture ,Durum wheat ,Overwintering ,triticum durum ,2. Zero hunger ,rouille jaune du blé ,Ecology ,food and beverages ,Puccinia triticina ,puccinia ,04 agricultural and veterinary sciences ,15. Life on land ,Foliar diseases ,modèle couplé stics - mila ,Agronomy ,blé dur ,13. Climate action ,hard wheat ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Climate change impact ,adaptation au changement climatique ,haute température ,Agronomy and Crop Science ,010606 plant biology & botany - Abstract
Leaf rust is responsible for significant wheat yield losses. Its occurrence and severity have increased in recent years, partly because of warmer climate. It is therefore critical to understand and anticipate the effects of climate change on leaf rust. Direct climate effects and indirect effects via host plants that provide a biophysical environment for disease development were both considered. The coupled STICS-MILA model simulates both crop and pathogen dynamics in a mechanistic way and their interaction is managed by two sub-models: one calculating the microclimate within the canopy and the other converting numbers of spores and lesions to affected surfaces. In this study, STICS-MILA was first calibrated and evaluated using leaf rust severity observed at various sites in France for multiple years. STICS-MILA was then run on three contrasting French sites under 2.6, 4.5 and 8.5 RCP future climate scenarios. Results focused firstly on changes in disease earliness and intensity, secondly on disease dynamics, particularly the synchronism between plant and disease developments, and finally on elementary epidemic processes. The calibration and evaluation of STICS-MILA revealed a high sensitivity to the initial amount of primary inoculum (a forcing variable in STICS-MILA) and thus the need to properly simulate the summering and overwintering pathogen survival. The simulations in the context of future climate showed a significant change in host-pathogen synchronism: in the far future, according to RCP 4.5 and 8.5 scenarios, disease onset is expected to occur not only with an advance of around one month but also at an earlier developmental stage of wheat crops. This positive effect results from rising temperatures, nevertheless partly counter-balanced during spring by lower wetness frequency. The crop growth accelerates during juvenile stages, providing a greater support for disease development. The resulting microclimate shortens latency periods and increases infection and sporulation efficiencies, thus causing more infectious cycles. An increase of final disease severity is thus forecasted with climate change.
- Published
- 2017