Agriculture Reference
In-Depth Information
Fig. 9.1
Effect of PSB and
PR with OA on phosphatase
activity in rice roots.
PSB16
¼Bacillus
sp., PSB
0
¼
non-inoculated,
CIPR
¼
phosphate rock,
OA
¼
oxalic acid
12
10
CIPR0
CIPR60
8
6
4
2
0
CIPR60
CIPR0
Fig. 9.2
Effect of PSB and
PR with OA on phytase
activity in rice roots.
PSB16
30
25
CIPR0
CIPR60
¼
Bacillus
sp., PSB
0
non-inoculated,
CIPR
¼
20
phosphate rock,
OA
¼
oxalic acid
¼
15
10
5
CIPR60
0
CIPR0
specific activity (
32
P) in the aerobic rice tissue showed a positive effect of PSB
inoculation or OA application to make the bioavailable P from PR and native soil
sources (Table
9.5
). This result is in concurrence with the earlier findings of Bolan
(
1991
), who found lower values of
32
P in the inoculated treatments. The PSB
treatments showed effectiveness at releasing
31
P from sparingly soluble sources
and the total amount of P derived either from the available (labeled) soil fraction
(Pdfl) or from the added PR (PdfCIPR) in plants. In fact, PSB released P from the
low-available P sources. The inoculation of PSB with CIPR (expand) and OA
showed higher values in plant P uptake and the amount of P derived from the
unavailable sources. Our results are in agreement with the findings of Toro
et al. (
1997
), who also found that plant total P and
32
P activity were lowered due