Response of Sorghum bicolor L. to Residual Phosphate on Two Contrasting Soils Previously Planted to Cowpea or Maize
Table 3
Effects of phosphorus sources as well as soil characteristics P sources interaction on fresh and dry shoot weight, relative agronomic efficiency, and P uptake of maize and cowpea in the first cropping.
Treatment
Fresh weight (g/pot)
RAE (%)
Dry weight (g/pot)
RAE (%)
P uptake (mg/pot)
P sources
Maize
P0
76.27
—
11.50
—
0.23
MRP
95.83
68.97
15.63
98.33
0.27
SRP
96.48
71.26
13.57
49.29
0.28
SSP
104.63
100.00
15.70
100.00
0.25
LSD (5%)
17.14
1.77
NS
Cowpea
P0
58.86
—
7.38
—
0.12
MRP
69.53
120.29
9.73
112.98
0.16
SRP
43.21
−176.44
5.62
−84.62
0.10
SSP
67.73
100.00
9.46
100.00
0.17
LSD (5%)
13.74
2.51
0.66
Soil P sources
Maize
Strongly acidic soil P0
31.20
—
4.30
—
0.06
Strongly acidic soil MRP
65.10
69.57
10.60
78.07
0.22
Strongly acidic soil SRP
69.33
78.25
9.67
66.54
0.25
Strongly acidic soil SSP
79.93
100.00
12.37
100.00
0.18
Slightly acidic soil P0
121.33
—
18.70
—
0.39
Slightly acidic soil MRP
126.57
65.50
20.67
596.97
0.31
Slightly acidic soil SRP
123.63
28.75
17.47
ND
0.31
Slightly acidic soil SSP
129.33
100.00
19.03
100.00
0.32
LSD (5%)
2.50
0.13
P0: control, MRP: Morocco rock phosphate, SRP: Sokoto rock phosphate, SSP: single superphosphate, NS: not significant (), ND: not determined, and RAE = [(GRP − CONTROL/SSP − CONTROL) × 100]%.
