The Hidden Costs of Nighttime Warming on Yields

Abstract

Nighttime warming poses a threat to global food security as it is driving yield declines worldwide, but our understanding of the physiological basis of this phenomenon remains very limited. Furthermore, it is often assumed that such declines are driven solely by increases in nighttime temperature (T_Night). Here we argue that, in addition to temperature, increases in nighttime evaporative demand may 'conspire' to penalize yields and end-use quality traits. We propose an ecophysiological framework outlining the possible mechanistic basis of such declines in yield and quality. We suggest ways to use the proposed framework as a guide to future efforts aimed at alleviating productivity losses by integrating crop ecophysiology with modeling, breeding, and management.

Keywords: drought tolerance; nighttime respiration; nighttime temperature; nighttime vapor pressure deficit; water use efficiency.