Water-Use Efficiency: Advances and Challenges in a Changing Climate

Water use efficiency (WUE) is defined as the amount of carbon assimilated as biomass or grain produced per unit of water used by the crop. One of the primary questions being asked is how plants will respond to a changing climate with changes in temperature, precipitation, and carbon dioxide (CO2) that affect their WUE At the leaf level, increasing CO2 increases WUE until the leaf is exposed to temperatures exceeded the optimum for growth (i.e., heat stress) and then WUE begins to decline. Leaves subjected to water deficits (i.e., drought stress) show varying responses in WUE. The response of WUE at the leaf level is directly related to the physiological processes controlling the gradients of CO2 and H2O, e.g.,…

• UD
  U.S. Department of Agriculture

  Award: 2015-68007-23133
• NI
  National Institute of Food and Agriculture

  Award: 2015-68007-23133
• AR
  Agricultural Research Service