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Summary: Understanding the genetic and physiological basis of abiotic stress tolerance under field conditions is key to varietal crop improvement in the face of climate variability. Here, we investigate dynamic physiological responses to water stress in silico and their relationships to genotypic variation in hydraulic traits of cotton (Gossypium hirsutum), an economically important species for renewable textile fiber production.In conjunction with an ecophysiological process‐based model, heterogeneous data (plant hydraulic traits, spatially‐distributed soil texture, soil water content and canopy temperature) were used to examine hydraulic characteristics of cotton, evaluate their consequences on whole plant performance under drought, and explore potential genotype × environment effects.Cotton was found to have R‐shaped hydraulic vulnerability curves (VCs), which were consistent under drought stress initiated at flowering. Stem VCs, expressed as percent loss of conductivity, differed across genotypes, whereas root VCs did not. Simulation results demonstrated how plant physiological stress can depend on the interaction between soil properties and irrigation management, which in turn affect genotypic rankings of transpiration in a time‐dependent manner.Our study shows how a process‐based modeling framework can be used to link genotypic variation in hydraulic traits to differential acclimating behaviors under drought. [ABSTRACT FROM AUTHOR]

Summary: Recent research has shown that plant acclimation to diverse patterns of light intensity modifies the dynamics of their stomatal response. Therefore, whether plants are grown in controlled conditions or in the field may impact their stomatal dynamics.We analysed the stomatal dynamics of two Populus euramericana and two Populus nigra genotypes grown in the field under contrasting water availability. By comparing their stomatal dynamics with that of the same genotypes grown in a glasshouse, we were able to test whether differences between these growing conditions interacted with genotypic differences in affecting stomatal dynamics and responses to soil water deficit.We found that, despite higher stomatal density and smaller size, in the field stomatal dynamics were much slower than in the glasshouse. Overall, differences among genotypes and their response to soil water deficit were much less pronounced in the field compared with the glasshouse.These results indicate that stomatal dynamics are regulated by both genotype‐specific and environmental factors. Moreover, having slower stomata may be advantageous under some conditions. While stomatal dynamics were linked with whole‐plant transpiration per leaf area in both experiments, the contribution of stomatal morphology varies dependent on the environmental conditions. [ABSTRACT FROM AUTHOR]

•Because the phenology of trees is strongly driven by environmental factors such as temperature, climate change has already altered the vegetative and repro-ductive phenology of many species, especially in the temperate zone. Here, we aimed to determine whether projected levels of warming for the upcoming decades will lead to linear changes in the phenology of trees or to more complex responses. •We report the results of a 3-yr common garden experiment designed to study the phenological response to artificial climate change, obtained through experimental warming and reduced precipitation, of several populations of three European oaks, two deciduous species ( Quercus robur, Quercus pubescens) and one evergreen species ( Quercus ilex), in a Mediterranean site. •Experimental warming advanced the seedlings’ vegetative phenology, causing a longer growing season and higher mortality. However, the rate of advancement of leaf unfolding date was decreased with increasing temperature. Conversely, soil water content did not affect the phenology of the seedlings or their survival. •Our results show that the phenological response of trees to climate change may be nonlinear, and suggest that predictions of phenological changes in the future should not be built on extrapolations of current observed trends. [ABSTRACT FROM AUTHOR]