Feibo Wu
Zhejiang University, China
Title: Tolerance to combined stress of drought and salinity in Tibetan wild barley
Biography
Biography: Feibo Wu
Abstract
Drought and salinity are the major abiotic stresses that limit agricultural production and dramatically threaten the food supply worldwide. Development of barley for improved drought and salinity resistance requires the knowledge of physiological mechanisms and genetic control of the contributing traits. Tibetan annual wild barley is rich in genetic variation. Here, we demonstrate the physiological and molecular differences between Tibetan wild (XZ5, drought-tolerant; XZ16, salinity/aluminum-tolerant) and cv. CM72 (salinity tolerant cultivar) in response to individual and combined stresses (D+S) of drought (4% soil moisture, D) and salinity (S). Tibetan wild barley XZ5/XZ16 showed to be more tolerant to combined stress of drought and salinity than cv. CM72. The stress tolerance mechanism of wild barley is partially attributed to lower Na+/K+ ratio, improved water use efficiency (WUE), increased capacity of anti-oxidative enzymes to scavenge reactive oxygen species (ROS), increased activities of the carbohydrate and secondary metabolism related enzymes relative to cv. CM72. Comparative proteomic analysis identified 34 differentially expressed proteins (DEPs) related tolerance to drought and salinity alone or a combination. Differentially regulated proteins predominantly had functions in photosynthesis, but also in detoxification, energy metabolism, and protein biosynthesis. Importantly, identification of stress responsive proteins and higher expression of their related genes i.e. SAM3, BSA1, PDX11 and TUFA in Tibetan wild barley represents the stress adaption mechanisms. Our findings add knowledge that wild barley is a treasure trove of useful genes and offer rich sources of genetic variation which can be exploited
in future efforts for breeding barley for multiple stress tolerance.