# Estimation of Photosynthetic Induction Is Significantly Affected by Light Environments of Local Leaves and Whole Plants in Oryza Genus

## TL;DR

This study shows how light conditions at the leaf and whole plant levels strongly affect photosynthetic induction in rice species.

## Contribution

The study reveals that IRGA chamber and whole plant illumination significantly influence photosynthetic induction through stomatal and biochemical changes.

## Key findings

- IRGA chamber and whole plant illumination significantly enhance photosynthetic induction in rice species.
- Higher density of smaller stomata improves stomatal opening and photosynthetic induction under fluctuating light.
- Stomatal morphology has minimal impact on steady-state gas exchange under constant light.

## Abstract

Photosynthetic induction and stomatal kinetics are acknowledged as pivotal factors in regulating both plant growth and water use efficiency under fluctuating light conditions. However, the considerable variability in methodologies and light regimes used to assess the dynamics of photosynthesis (A) and stomatal conductance (gs) during light induction across studies poses challenges for comparison across species. Moreover, the influence of stomatal morphology on both steady-state and non-steady-state gs remains poorly understood. In this study, we show the strong impact of IRGA Chamber Illumination and Whole Plant Illumination on the photosynthetic induction of two rice species. Our findings reveal that these illuminations significantly enhance photosynthetic induction by modulating both stomatal and biochemical processes. Moreover, we observed that a higher density of smaller stomata plays a critical role in enhancing the stomatal opening and photosynthetic induction to fluctuating light conditions, although it exerts minimal influence on steady-state gs and A under constant light conditions. Therefore, future studies aiming to estimate photosynthetic induction and stomatal kinetics should consider the light environments at both the leaf and whole plant levels.