Watts-Williams, S.J.,
Smith, F.A.,
Smith, F.A.,
and Jakobsen, I.
2019
"Soil phosphorus availability
is a driver of the responses
of maize (Zea mays)
to elevated CO2 concentration
and arbuscular mycorrhizal
colonization."
Symbiosis 77: 73-82
NOTE:
Arbuscular mycorrhizal fungi (AMF)
maintain a symbiotic relationship
with certain plants, providing
those the plants with valuable
soil nutrients and in return
receive carbon resources.
Both plant and fungi growth
are enhanced.
SUMMARY:
Watts-Williams et al. (2019)
examined the interactive response
between AMF, soil phosphorus (P)
supply and atmospheric CO2
concentration on the growth
of maize (Zea mays, cv. B73).
Regardless of phosphorus
supply or AMF presence,
rising atmospheric CO2
concentrations will likely
enhance the growth
of maize plants.
The observations add to the
"growing body
of literature
of literature
that challenges
the classic theory
that C4 plants
[ like maize ]
[ like maize ]
are non-responsive
to elevated CO2."
This study will help scientists
and farmers select the best
possible growing conditions
to maximize future yields.
DETAILS:
The experiment was conducted
in pots in controlled indoor
environments over a period
of 40 days.
AMF treatments included with
or without inoculation,
soil P supply treatments
included 0, 15 or 90 mg P kg-1 soil
and atmospheric CO2 treatments
included 400 or 900 ppm.
The scientists report that maize shoot
and root dry weights increased
with P supply and CO2 concentration,
albeit the increases were
more noticeable and significant
for shoot dry weights
than they were for the roots.
The greatest relative CO2 increase
in dry weight (+33.3%)
occurred in maize plants
growing without AMF inoculation
in the no P added treatment.
In contrast, the smallest
CO2 growth response (+4.6%)
was observed in plants
subjected to AMF inoculation
in the no P added treatment.
