The leaf/stem biomass ratio (A) and leaf nitrogen content (B) of <i>Panicum maximum</i> under regular concentration of CO₂ and canopy temperature (Control), under elevated CO₂ concentration of 600 ppm (eC), under elevated canopy temperature of +2°C (eT), and under both treatments (eC+eT).

<p>Bars show average values and lines at the top of the bars the standard error. Different letters above the bars indicate significant differences among the datasets after the Mann-Whitney test at p < 0.1.</p

Average values of leaf biomass as a function of leaf area per tiller of <i>Panicum maximum</i> under regular atmospheric CO₂ concentration and canopy temperature (Control, A), under elevated atmospheric CO₂ concentration of 600 ppm (eC, B), under elevated canopy temperature of +2°C (eT, C), and under both treatments (eC+eT, D).

<p>Average values of leaf biomass as a function of leaf area per tiller of <i>Panicum maximum</i> under regular atmospheric CO₂ concentration and canopy temperature (Control, A), under elevated atmospheric CO₂ concentration of 600 ppm (eC, B), under elevated canopy temperature of +2°C (eT, C), and under both treatments (eC+eT, D).</p

Leaf appearance rate (A), leaf elongation rate (B), leaf area (C), and leaf biomass (D) per tiller of <i>Panicum maximum</i> under regular CO₂ and canopy temperature (Control), under elevated CO₂ concentration of 600 ppm (eC), under elevated canopy temperature of +2°C (eT), and under both treatments (eC+eT).

<p>Bars show average values and lines at the top of the bars show the standard error. Different letters above bars indicate significant differences among datasets according to a Mann-Whitney test at p < 0.05.</p

Accumulated number of expanded (A), expanding (B), and senescent (C) leaves; and the mean number of cut-expanded leaves (D) per tiller of <i>Panicum maximum</i> growing under different atmospheric conditions.

<p>A—Regular concentration of CO₂ and canopy temperature (Control). B—Elevated CO₂ concentration of 600 ppm (eC). C—Elevated canopy temperature of +2°C (eT). D—Combination of treatments (eC+eT). The days of measurement were August 22 and 29, and September 3, 9, 12, and 20, 2013.</p