Jeudi 18 janvier 2018 (Amphi 208) à 14h00
Ning TANG (B&PMP équipe Aquaporines)
Yin-Yang in plant water relations and stress responses
Water usage by plants, especially in the context of climate change, has become a key issue in both ecology and agriculture. In particular, we need to understand how combined genetic and physiological adjustments of root water uptake contribute to plant adaptation to specific habitats or climatic scenarios. Root water transport capacity (i.e. root hydraulics) is a key trait during these processes. To get a species-wide picture of the genetic diversity of this trait, we analyzed Arabidopsis thaliana in genome-wide association studies and uncovered XYLEM NAC DOMAIN 1 (XND1) as a major genetic component of root hydraulic conductivity (Lpr), in relation to unsuspected roles of vascular tissues. This work also revealed a novel mechanism for trade-off between abiotic stress tolerance and biotic defense in plants. In addition, our work in rice elucidated complex interactions between key transcription regulators, OsbZIP46 and MODD (mediator of OsbZIP46 deactivation and degradation), in fine-tuning abscisic acid (ABA) signaling and drought stress response. Taken together, these findings show that plants have evolved elaborate protective mechanisms, involving the coordination and balance of genetic and physiological factors, to confer fitness and survive adverse conditions.