Dabu, X., Li, S.,
Cai, Z., Ge, T.
and Hai, M.
2019
The effect of potassium
on photosynthetic
acclimation in cucumbers
during CO2 enrichment.
Photosynthetica 57: 640-645
SUMMARY:
Dabu et al. (2019)
studied the
combined effects
of elevated CO2
and potassium
on the growth
of cucumber
(Cucumis sativus
cv. Zhongnong 20).
Elevated CO2 increased
the total biomass
of the cucumbers by
+73% and +33% in the
K120 and K240 potassium
treatments, respectively.
Higher potassium
concentrations also
positively impacted
biomass, helping
to increase
the transport
of photosynthetic
products
from the leaves
into other plant organs
(e.g., stems, roots).
A mere 4 hours of
CO2 enrichment and
potassium application
can significantly improve
the growth of cucumbers.
This study is based on
only 4 hours of
CO2 enrichment
each morning --
it would seem logical
that 24 hours a day
of CO2 enrichment
would be even better !
DETAILS:
Work was conducted in
open-top chambers within
a controlled-environment
greenhouse at Yunnan
Agriculture University
in China.
Two-month-old cucumber
seedlings were grown
hydroponically in the
chambers for 43 days
under either
ambient (380 ppm) or
elevated (1000 ppm)
CO2 conditions,
with the elevated CO2
only being applied
in the morning
from 8 am to 12 pm.
Within each CO2 treatment
half the plants received
a potassium concentration
of 120 mg L-1 (K120)
and half a concentration
of 240 mg L-1 (K240).
