01677nas a2200145   4500008004100000245008900041210006900130300001500199490000700214520117000221100002001391700002301411700001901434856007801453       2012                        eng d00aChanges in stomatal conductance along grass blades reflect changes in leaf structure0 aChanges in stomatal conductance along grass blades reflect chang  a1040 -10490 v353 a<p>Identifying the consequences of grass blade morphology (long, narrow leaves) on the heterogeneity of gas exchange is fundamental to an understanding of the physiology of this growth form. We examined acropetal changes in anatomy, hydraulic conductivity and rates of gas exchange in five grass species (including C3 and C4 functional types). Both stomatal conductance and photosynthesis increased along all grass blades despite constant light availability. Hydraulic efficiency within the xylem remained constant along the leaf, but structural changes outside the xylem changed in concert with stomatal conductance. Stomatal density and stomatal pore index remained constant along grass blades but interveinal distance decreased acropetally resulting in a decreased path length for water movement from vascular bundle to stomate. The increase in stomatal conductance was correlated with the decreased path length through the leaf mesophyll. A strong correlation between the distance from vascular bundles to stomatal pores and stomatal conductance has been identified across species; our results suggest this relationship also exists within individual leaves.</p>1 aOcheltree, T.W.1 aNippert, Jesse, B.1 aPrasad, P.V.V.  uhttps://onlinelibrary.wiley.com/doi/full/10.1111/j.1365-3040.2011.02470.x