Response to atmospheric CO₂ concentration of number of leaves appeared on main culm (A), number of tillers produced per hill (B) and leaf area index (C) at flowering stage.

<p>Error bars indicate SEM of means of biological replications within a chamber and not replications of treatment.</p

Observations and ANOVA for measured days from sowing to flowering, days from sowing to grain maturity and aboveground dry weight (agdw) for four CO₂ concentration treatments and four seasons.

<p>Observations and ANOVA for measured days from sowing to flowering, days from sowing to grain maturity and aboveground dry weight (agdw) for four CO₂ concentration treatments and four seasons.</p

Sowing date and mean daily solar radiation (Rs) at canopy tops in the chambers; for four CO₂ concentrations and two dry seasons (DS) and two wet season (WS).

<p>Sowing date and mean daily solar radiation (Rs) at canopy tops in the chambers; for four CO₂ concentrations and two dry seasons (DS) and two wet season (WS).</p

CO₂ concentration effect on cumulative ET as directly measured during 27 days of observation (for daily values see Table 3) and for the whole crop cycle (extrapolated using the model in S1 Fig).

<p>CO₂ concentration effect on cumulative ET as directly measured during 27 days of observation (for daily values see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0169706#pone.0169706.t003" target="_blank">Table 3</a>) and for the whole crop cycle (extrapolated using the model in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0169706#pone.0169706.s002" target="_blank">S1 Fig</a>).</p

Summary of mean climate variables inside the CO₂ chambers observed during the crop cycle in WS 2013 on top of the crop canopy.

<p>Summary of mean climate variables inside the CO₂ chambers observed during the crop cycle in WS 2013 on top of the crop canopy.</p

The effect of maleic hydrazide (MH) on the pre-anthesis anthers of <i>Setaria</i>.

<p>(A) Untreated control spikelet and (B) spikelet treated with 500 μM MH. (C and D) Androecium and gynoecium of control and MH-treated spikelets, respectively. (E and F) Anthers of control and MH-treated spikelets, respectively. (G and H) A representative anther of control and MH-treated spikelets, respectively. (I) In control panicles, mature seeds were observed in the spikelets. (J) Brown specks were observed as remnants of anther dehiscence in the MH-treated panicles and no seeds were set although the florets remained green. The scale bar represents 5 mm in A and B, 0.5 mm in C, D, E and F, and 0.75 mm in G and H; I and J are not to scale.</p

Daily measured evapotranspiration (ET), calculated potential evapotranspiration (ET_o), and derived crop coefficient (K_C = ET ETo-1) for 27 days in the growth chambers having different CO₂ concentration.

<p>Daily measured evapotranspiration (ET), calculated potential evapotranspiration (ET_o), and derived crop coefficient (K_C = ET ETo-1) for 27 days in the growth chambers having different CO₂ concentration.</p

Atmospheric CO₂ concentration effects on rice water use and biomass production - Fig 1

<p>A: Response of final above ground dry weight (agdw) to atmospheric CO₂ concentration for two dry seasons (DS) and two wet seasons (WS), differing in solar radiation levels. B: Dynamics of potential ET (ET_o, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0169706#pone.0169706.t003" target="_blank">Table 3</a>) and crop ET in 2013 WS. C: Dynamics of crop coefficient Kc (ET/ET_o) in 2013 WS. D: Response of Kc to atmospheric CO₂ concentration during three periods of crop development. Error bars represent SEM for multiple measurements on different plants within a chamber.</p

Atmospheric CO₂ concentration effects on rice water use and biomass production - Fig 3

<p>A: Response to atmospheric CO₂ concentration of final total agdw (TDW) and cumulative crop water use. Water use was calculated from daily calculations of Kc as shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0169706#pone.0169706.s002" target="_blank">S1 Fig</a>. B: Response of leaf-level transpiration efficiency (TE) and crop-level water use efficiency (WUE).</p

Manual emasculation of <i>Setaria viridis</i>.

<p>Equipment needed for manual emasculation included (A) a magnifying glass, (B) glassine bag, scissors, forceps and ear pick. (C) A panicle of correct developmental stage, when the lowest spikelet of the panicle was between 0 to 2 cm from the collar of the flag leaf, was selected for emasculation. (D) The spikelets from the tip and base of the panicle were trimmed leaving approximately 10 to 20 spikelets, and then their bristles were trimmed. (E) One third of each spikelet was removed using sharp scissors and then all three anthers from each spikelet of the panicle were removed using an ear pick and/or forceps. (F) The emasculated panicles were enclosed in glassine bags. (G) On the following day, the spikelets were checked and were dusted with pollen. (H) The pollination was repeated for two days. (I) The emasculated and pollinated panicles were then bagged until seed set. (J) Seed set was checked 10 to 12 days after pollination, if immature seed germination was required. (K) The seeds were allowed to mature and were harvested with care to avoid shattering.</p