Update: Impacts of fluctuating light on crop performance

Light intensity varies seasonally, with time of day, with cloudiness, and as overlying leaves move in the wind.  A sudden change in light intensity alters photosynthetic responses, but not all responses change at the same rate. For example, upon an increase in light intensity, photosynthetic electron transport can be upregulated more rapidly than stomatal conductance, affecting photosynthetic productivity. Sluggishness in stomatal closure in response to shade can adversely affect water-use efficiency. Slattery et al. explore how various facets affect photosynthesis in fluctuating light, and compare the impacts on C3 versus C4 plants. The “lagging response of photosynthesis to both increasing and decreasing light intensity… reveals opportunities for improving performance”, but more studies in natural, light-fluctuating environments are needed.  (Summary by Mary Williams) Plant Physiol. 10.1104/pp.17.01234