Natural genetic variation of the photosynthetic induction response to fluctuating light environment.

Field-grown plants experience fluctuating light intensity for periods extending from seconds to hours because of cloud movements and self-shading. When full light intensity returns after shading, the net CO2 assimilation rate in leaves does not reach its maximum value immediately, but rises gradually over several minutes to approach a new steady state. This phenomenon has been termed photosynthetic induction, which substantially affects the efficiency of carbon fixation, and thus crop production. The significant natural variation of the speed of induction response exists among not only interspecies but also intraspecies. Recent advances in molecular analysis and high-throughput measurement techniques have revealed the genetic and eco-physiological basis of observed genetic variations in photosynthetic induction response. Here, we review the current understanding of the physiological and genetic mechanisms behind photosynthetic induction, and discusses routes to further advances.