AUTHOR=Ye Miao , Wu Meng , Zhang Hao , Zhang Zuolin , Zhang Zujian 

TITLE=High Leaf Vein Density Promotes Leaf Gas Exchange by Enhancing Leaf Hydraulic Conductance in Oryza sativa L. Plants

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.693815

DOI=10.3389/fpls.2021.693815

ISSN=1664-462X

ABSTRACT=<p>Six cultivated rice genotypes showing different stomatal conductance (<italic>g</italic><sub>s</sub>) values were used to investigate the influence of leaf vein traits on leaf gas exchange and leaf hydraulics. The results showed that <italic>g</italic><sub>s</sub> was the main determinant of the varietal difference in the net photosynthetic rate (<italic>P</italic><sub>N</sub>), whereas the area-based leaf nitrogen content (N<sub>area</sub>) and mesophyll conductance (<italic>g</italic><sub>m</sub>) were not main factors. <italic>g</italic><sub>s</sub> and <italic>P</italic><sub>N</sub> were both positively correlated with leaf hydraulic conductance (<italic>K</italic><sub>leaf</sub>). A high density of leaf veins (vein length per leaf area, VLA), especially minor leaf veins (VLA<sub>minor</sub>), was of benefit for improving the <italic>K</italic><sub>leaf</sub>. The proportion of the minor leaf vein length to the total leaf vein length did not impact the leaf hydraulics or leaf gas exchange. Overall, these findings suggested that a high density of leaf veins, especially minor leaf veins, enhances <italic>K</italic><sub>leaf</sub> and promotes <italic>g</italic><sub>s</sub> and <italic>P</italic><sub>N</sub> in cultivated rice genotypes and a high VLA can be regarded as a high photosynthetic capacity trait in rice plants.</p>