Abstract
Plant roots can be colonized by many symbiotic fungi, whereas it is unclear whether and how symbiotic fungi including arbuscular mycorrhizal fungi and endophytic fungi promote phosphorus (P) uptake in
Camellia oleifera
plants. The objective of the present study was to analyze the effect of inoculation with a culturable endophytic fungus (
Piriformospora indica
), three arbuscular mycorrhizal fungi (
Funneliformis mosseae
,
Diversispora versiformis
, and
Rhizophagus intraradices
), and mixture of
F
.
mosseae
,
D
.
versiformis
and
R
.
intraradices
on plant growth, root architecture, soil Olsen-P, soil phosphatase activities, leaf and root P concentrations, and phosphate transporter gene expressions, in order to explore the potential and mechanism of these symbiotic fungi on P acquisition. All the symbiotic fungi colonized roots of
C
.
oleifera
after 16 weeks, with
P
.
indica
showing the best effect on fungal colonization. All the symbiotic fungi significantly increased acid, neutral, and total phosphatase activities in the soil, accompanied with an elevation of soil Olsen-P, of which
P
.
indica
presented the best effect. All symbiotic fungal treatments, except
D
.
versiformis
, significantly promoted plant growth, coupled with an increase in root total length, area, and volume. Symbiotic fungi almost up-regulated root
CoPHO1-3
expressions as well as leaf
CoPHO1-1
,
CoPHO1-3
, and
CoPHT1;4
expressions. Correlation analysis showed that P concentrations in leaves and roots were significantly positively correlated with root morphological variables (length, volume, and surface area) and soil acid, neutral and total phosphatase activities. It is concluded that symbiotic fungi, especially
P
.
indica
, played an important role in P uptake of
C
.
oleifera
plants through regulating root architecture, part plant phosphate transporter gene expressions and soil phosphatase activities.