Abstract:
Concentration of CO
2
in the atmosphere is likely to increase up to 550 μ
mol mol
-1
by the
middle of 21
st
century. Such an increase in the atmospheric CO
2
would affect plant
growth, and as well the productivity of crop plants
. A field experiment was conducted
with two potato cultivars namely Kufri Surya and Ku
fri Chipsona-3 grown inside Open
Top Chambers (OTCs) at ambient (385±30 μmol mol
-1
)
vs.
elevated CO
2
(570±50 μmol
mol
-1
) levels during
rabi
(winter) season of the year 2009-2010. The photosy
nthetic rate
significantly increased in both cultivars when unde
r high CO
2
concentration, with the
enhancement being more in Kufri Chipsona-3 than in
Kufri Surya. There were
significantly increased accumulations of reducing,
non-reducing and total sugars
observed in the leaves of both cultivars as due to
CO
2
enrichment. Crop Growth Rate
(CGR) and Tuber Growth Rate (TGR), in both cultivar
s, were recorded higher in plants
grown under elevated CO
2
as compared with the ambient CO
2
content. High CO
2
increased the partitioning of dry matter towards th
e tubers at all the harvesting stages.
Potato plants grown under elevated CO
2
exhibited increased tuber yield due to the
enhanced number of tubers per plant. At the final h
arvest, total tuber fresh weight was by
36% higher, under high CO
2
treatments, as compared with that in the ambient.
The
response of K. Chipsona-3 was more pronounced, to e
levated CO
2
concentration, as
compared with K. Surya. It is concluded that rising
atmospheric CO
2
in the future
climatic change scenario may be beneficial to such
tuber crops like potato to enhance
growth as well as tuber number and finally yield.
