Phenological and epidemiological impacts of climate change on peach production

CONTEXT: Agricultural food security is threatened by climate change impacts, which can distress crop growth and favor the spread of infectious diseases. OBJECTIVE: We aim to examine the synergism of two potential causes of future yield failure in peach production: the effects of global climate change on fruit tree blooming and on the spread of fungal diseases. METHODS: The 'disease triangle ', well-known concept in plant pathology that represents the interplay between the environment, plant hosts, and pathogens, was evaluated for brown rot in peach orchards in light of climate change. Coupling a climate -driven mechanistic phenological and epidemiological model across the French continental territory, we provided projections of yield losses for four peach cultivars (early, mid -early, mid -late, and late) in the XXI century under different climate change scenarios. We considered as adaptation strategy the possibility of shifting peach production sites to new suitable areas. RESULTS AND CONCLUSIONS: Global warming is expected to impair fruit phenology with blooming failure events in the south-western part of the country that comprise the 31% of the French territory at the end of the XXI century. This will be less extreme under the more moderate greenhouse gas (GHG) emission scenario, even though sporadic blooming failures will still occur that will involve less than the 10% of the French territory. In contrast, future warmer and drier conditions will decrease brown rot -induced yield loss in the historical locations devoted to peach cultivation. Thanks to the considered adaptation strategy, the peach national yield could still be fulfilled even under the most extreme GHG emission scenario. SIGNIFICANCE: Comprehensive mathematical frameworks, that concomitantly consider the climatic effects on the plant hosts and on their pathogens, are required to provide reliable future predictions of crop yields and to inform control and adaptation strategies to guarantee food security under global warming.