Lenka, N.K., Lenka, S.,
Singh, K.K., Kumar, A.,
Aher, S.B.,Yashona, D.S.,
Dey, P., Agrawal, P.K.,
Biswas, A.K. and Patra, A.K.
2019
Effect of elevated carbon dioxide
on growth, nutrient partitioning,
and uptake of major nutrients
by soybean under varied
nitrogen application levels.
Journal of Plant Nutrition
and Soil Science 182: 509-514.
NOTE:
Field studies on elevated CO2
and nitrogen (N) supply
on plant metabolism and
nutrient assimilation
are scarce for soybean.
Lenka et al. (2019)
investigated the effects of
elevated CO2 and various
levels of Nitrogen supply
on the biomass, grain yield,
nutrient concentration
and uptake of soybeans.
SUMMARY:
The ten Indian researchers
report that both elevated CO2
and N-supply positively
impacted soybean growth
and yield.
Both elevated CO2 and N-supply
improve soybean seed yield,
with the greatest yield value
observed under elevated CO2
and 100% of the recommended
supply of N.
These improved yield gains
come with no effect on seed
N or K concentration
and only minimal decline
of P concentration,
which decline would
most likely be overcome
with the application
of a little more P-supply
as a soil management
technique.
DETAILS:
Aboveground biomass
of soybean at harvest
increased by +40, +38,
+65 and +30% in the
0, 50, 100 and 150%
N supply treatments,
respectively.
Soybean seed yield increased
by +39, +59, +51 and +26% in the
0, 50, 100 and 150% N supply
treatments, also respective.
Under elevated CO2,
the highest aboveground
biomass and seed yield
values occurred in the
normal N supply treatment
(i.e., 100% of N supply
recommendation).
Under ambient CO2,
they occurred in the
150% of normal
N treatment.
The work was conducted
in open-top chambers
at a research farm of the
Indian Institute of Soil Science,
Bhopal, Pune, India in 2016.
The two CO2 concentrations
investigated were ambient
(395 ppm)
and elevated
(535 ppm, applied daylight hours only),
and the four N-supply levels
included 0, 50, 100 and 150%
of the normal recommended
dose.
Two other nutrients,
phosphorus (P) and
potassium (K),
were supplied in
each treatment
at their normal
recommended dose.
The soybean cultivar
used in the experiment
was JS-20-29.
Lenka et al. also found that
soybean seed N and K
concentrations were
unaffected by either
CO2 or N application.
Seed P concentration,
on the other hand,
was reduced in all
N applications
under elevated CO2
with the exception of the
highest N supply treatment.
More specifically,
seed P decreased by
7, 9 and 3% in the
0, 50% and 100%
N-supply treatments,
whereas it increased by 7.5%
at the highest N-supply level
(150% of normal).
Despite the relative decline
in seed P concentration
at elevated CO2,
the total plant P uptake
significantly increased
by 23-62% depending on
N-supply level.
Elevated CO2
also stimulated
plant N and K uptake
by 18-61% and 22-62%
at the various N treatments.
