The response of mesophyll conductance and Rubisco activity to water stress vary with the rice supplied nitrogen nutrition

<b>Figure 1</b> Rice xylem sap amount (A), root secretion rate (B) and water use efficiency (C) under different N forms and water conditions. The data refer to the mean ±SE (<i>n</i>=4). N, NP, A, AP, NA and NAP represent the nitrate (NO₃^-), NO₃^-+PEG6000, ammonium (NH₄⁺), NH₄⁺+PEG6000, mixture of ammonium and nitrate (NO₃^-+NH₄⁺) and NO₃^-+NH₄⁺+PEG6000 treatments, respectively. Significant differences (<i>p</i>&lt;5%) between treatments of rice are indicated by different letters. The same as below. <b>Figure 2</b> Rice leaf Chl (A), total N (B) and Rubisco (C) contents under the different N forms and water conditions. <b>Figure 3</b> The relationships of net photosynthesis (<i>A</i>) and water use efficiency (WUE) to the mesophyll conductance (<i>g_m</i>), stomatal conductance (<i>g_s</i>) and ratio of g_m/g_s in rice leaves.