calculates photosynthesis rate (i.e., flux, µmol·m −2 ·s −1 ) from direct measures (via two IRGAs) of the CO 2 concentration entering and exiting the leaf cuvette, relative to the leaf area in the cuvette (4.5 cm 2 ). CO 2 concentration was controlled (390
Not much is known about the influence of leaf position on photosynthesis in water-stressed leaves. We do know that stomatal control of water loss is an early plant response to water deficit under field conditions ( Chaves, 1991 ; Cornic and
therefore effectively enhance plant photosynthesis and growth ( Lu et al., 2015 ; Zhang et al., 2015 , 2017 , 2018 ). It is generally considered that the movement of water through the soil–plant–atmosphere continuum is driven by a gradient in water
photosynthesis in lower plant canopy levels and subsequently increase plant yield at the whole plant canopy level ( Dou et al., 2019a ; Terashima et al., 2009 ; Wang and Folta, 2013 ). In addition, G wavelengths induce shade avoidance responses in plants, such
stressors are known to create source–sink imbalances that can inhibit gene expression related to the production of chloroplast protein complexes, which can have a lasting negative effect on the photosynthesis rate (P n ) ( Balachandran et al. 1997 ). This
Photosynthesis was reduced by 85% to 90% in perennial ryegrass (Lolium perenne L. cv. Derby) following a one-day chilling exposure at 8C day (450 μmol·s-1·m-2 PPF) and 5C night. Seven days of recovery at 22/17C day/night were required for full recovery of photosynthesis. More than 75% of the limitation in photosynthesis following chilling was due to non-stomatal factors, and reduced initial slopes of CO2 assimilation vs. intercellular CO, indicate that photosynthetic capacity was reduced for 5 days following chilling. Carbon dioxide assimilation at saturating intercellular CO2 (>500 μmol·mol-l) was also reduced by chilling, indicating again that stomatal limitations were a minor contributor to the photosynthetic reduction observed under ambient CO2.
Over the past 15 years tremendous progress has been made in the study of photosynthetic pathways. It is now accepted that there are 3 distinct photo-synthetic pathways in higher plants: the Calvin-Benson pathway (C3 photosynthesis), the Hatch-Slack pathway (C4 photosynthesis), and Crassulacean Acid Metabolism (CAM photosynthesis). Much progress has been made in describing the biochemistry and physiology of these pathways, but less is understood of the.genetics, ecology, evolution, and regulation of these pathways. The purpose of this review will be to bring the reader up to date on the significant details of the biochemistry and physiology of the 3 photosynthetic pathways and to present an ecological/evolutionary view of the significance of differences in the pathways.
the photosynthetic characteristics, antioxidant system, and osmotic regulation of multiple vegetative organs of various crops have been studied. Salt stress can inhibit photosynthesis in plants (Han et al., 2014). High salt stress can reduce g S
photosynthesis ( Zelitch, 1982 ). The increases in yield over the last century have been largely the result of increases in harvest index and light interception; however, the role that photosynthesis has played is not completely understood ( Richards, 2000 ). In
environment) ( Fanourakis et al., 2016 ). Research has shown that VPD not only has a direct effect on stomatal conductance ( g s ), photosynthesis, and water transport ( Sinclair et al., 2007 ) but also affects plant temperature via transpiration. Greater VPD