show Abstracthide AbstractDespite that climate change is currently one of the most pervasive challenges, its effects on the plant-associated microbiomes is still poorly studied. The aim of this study was to evaluate the impact of climate warming and drought stress on the microbiome assembly of oak plants from seed to seedling. In a multifactorial experimental set up, acorns were subjected to different temperature (15, 20 and 25 degree Celsius) and soil moisture levels (drought and control) from germination until the seedling stage, after which the bacterial and fungal communities associated with the rhizosphere and phyllosphere of the seedlings were analyzed. The interaction of temperature and drought affected both the bacterial and the fungal communities, with the latter being more strongly affected. This effect was more significant in the phyllosphere and contrasting depending on soil moisture level. Both temperature and drought affect the microbial community composition with more profound effect in the rhizosphere. Regardless of temperature, Actinobacteriota was significantly enriched in drought conditions. This study provides new insights into climate change related impacts on the plant-associated microbiota of a major forest tree species such as oak.