Li, P., Hao, X., Aryal, M.,
Thompson, M. and
Seneweera, S.
2019
Elevated carbon dioxide
and nitrogen supply
affect photosynthesis
and nitrogen partitioning
of two wheat varieties.
Journal of Plant Nutrition 42: 1290-1300.
SUMMARY:
Wheat biomass of these
two cultivars improves,
along with their plant water
use efficiency,
as CO2 levels rise,
regardless of the
nitrogen treatment.
The authors say that
"elevated CO2 and
high N facilitate
the improvement
of photosynthesis
and, thus,
the biomass."
"Furthermore ...
intrinsic water use
efficiency of both
the cultivars were
significantly increased
at high N level
under elevated CO2."
DETAILS:
The study was conducted
in controlled-environment
chambers, where
two cultivars of wheat
(RAC0875 and Kukri)
were grown
for six weeks
under two
atmospheric CO2
concentrations
(400 or 700 ppm)
and one of four
nitrogen (N)
treatment levels
(0.2, 0.5, 1.0 or 3.0 mM N).
See chart below:
The top panel shows
plant above and below
ground biomass,
for representative plants
growing in each nitrogen
and CO2 treatment,
for both cultivars.
Top left and right panel:
Effect of elevated CO2 (C+)
on the growth
of two wheat varieties
(Rac0875, top left;
Kukri, top right)
at different levels
of nitrogen (N) supply
(N1, N2, N3 and N4
correspond to respective
N treatment levels of
0.2, 0.5, 1.0 or 3.0 mM).
The bottom panel:
Effect of elevated CO2
(ECO2) on intrinsic water
use efficiency (WUEi)
of wheat at different
Nitrogen supply
treatments.
