Depth (cm) |
Horizon |
Particle size (%) |
Textural Class |
Silt/ |
*BD |
TP (%) |
Water content |
||||
|
|
Sand |
Silt |
Clay |
|
|
|
|
FC (%) |
PWP (%) |
AWHC (mm m-1) |
0-25 |
H1 |
11 |
38 |
51 |
Clay-loam |
0.75 |
1.14 |
56.98 |
42 |
27 |
128.00 |
25-55 |
H2 |
13 |
37 |
50 |
Clay-loam |
0.74 |
1.23 |
53.58 |
39 |
25 |
125.00 |
55-80 |
H3 |
15 |
40 |
45 |
Clay-loam |
0.89 |
1.27 |
52.07 |
37 |
22 |
123.60 |
80-115 |
H4 |
15 |
52 |
33 |
Silty-loam |
1.58 |
1.26 |
52.45 |
37 |
22 |
123.60 |
115-155 |
H5 |
45 |
30 |
25 |
Sandy-loam |
1.20 |
1.21 |
50.34 |
29 |
16 |
110.50 |
155-200 |
H6 |
54.6 |
26.4 |
19 |
Sandy loam |
1.39 |
1.16 |
51.98 |
25 |
14 |
109.00 |
Composite surface (0 – 30 cm) soil samples before planting (from experimental nearby profile) |
|||||||||||
Block 1 |
- |
11 |
38 |
51 |
Clay-loam |
0.75 |
- |
- |
- |
- |
- |
Block 2 |
- |
12 |
37 |
49 |
Clay-loam |
0.76 |
- |
- |
- |
- |
- |
Block 3 |
- |
11 |
39 |
50 |
Clay-loam |
0.78 |
- |
- |
- |
- |
- |
Block 4 |
- |
11 |
38 |
51 |
Clay-loam |
0.75 |
- |
- |
- |
- |
- |
Block 5 |
- |
13 |
37 |
50 |
Clay-loam |
0.74 |
- |
- |
- |
- |
- |
Block 6 |
- |
12 |
37 |
49 |
Clay-loam |
0.76 |
- |
- |
- |
- |
- |
Mean |
|
12 |
38 |
50 |
Clay-loam |
0.76 |
- |
- |
- |
- |
- |
Table 1: Selected physical properties of the soil profile and composite surface soil samples of the study area
*BD = Bulk density; TP = Total porosity; FC = Field capacity; PWP = Permanent wilting point; AWHC = Available water holding capacity
Depth (cm) |
Horizon |
pH |
CaCO3 |
*OM |
C:N |
Total N |
Exchangeable bases and CEC soil (cmolc kg-1) |
PBS |
||||
|
|
|
|
|
|
|
Na |
K |
Mg |
Ca |
CEC |
|
0-25 |
H1 |
6.38 |
0.21 |
2.34 |
9.34 |
0.092 |
0.3 |
0.7 |
9.4 |
41 |
70.1 |
82.00 |
25-55 |
H2 |
6.65 |
0.24 |
2.12 |
9.05 |
0.086 |
0.5 |
0.8 |
10.24 |
42.3 |
60.5 |
90.5 |
55-80 |
H3 |
6.98 |
0.24 |
1.53 |
7.25 |
0.089 |
0.7 |
0.7 |
9.1 |
42.9 |
75.6 |
86.7 |
80-115 |
H4 |
7.79 |
0.35 |
0.89 |
10.17 |
0.053 |
0.8 |
0.8 |
9.04 |
48 |
58.4 |
110.5 |
115-155 |
H5 |
8.31 |
10.78 |
0.45 |
4.34 |
0.024 |
0.9 |
0.3 |
9.61 |
78.5 |
75.2 |
152.4 |
155-200 |
H6 |
8.22 |
3.15 |
0.08 |
3.95 |
0.011 |
1.3 |
0.31 |
10.8 |
61 |
62.7 |
136.8 |
Composite surface (0 – 30 cm) soil samples before planting (from experimental nearby profile) |
||||||||||||
Block 1 |
- |
6.38 |
0.21 |
2.41 |
9.34 |
0.092 |
0.3 |
1.05 |
9.60 |
40.00 |
73.10 |
78.00 |
Block 2 |
- |
6.15 |
0.23 |
2.402 |
9.25 |
0.096 |
0.3 |
0.95 |
10.28 |
41.30 |
65.50 |
69.50 |
Block 3 |
- |
6.49 |
0.24 |
2.39 |
8.95 |
0.089 |
0.3 |
1.01 |
10.23 |
39.90 |
61.60 |
71.70 |
Block 4 |
- |
6.55 |
0.25 |
2.46 |
8.97 |
0.083 |
0.3 |
1.03 |
9.54 |
41.40 |
59.40 |
70.50 |
Block 5 |
- |
6.05 |
0.22 |
2.37 |
9.21 |
0.094 |
0.3 |
0.98 |
9.61 |
38.50 |
62.20 |
62.40 |
Block 6 |
- |
6.27 |
0.25 |
2.44 |
9.05 |
0.091 |
0.3 |
0.97 |
10.80 |
36.75 |
62.75 |
59.84 |
Mean |
- |
6.32 |
0.23 |
2.412 |
9.13 |
0.091 |
0.3 |
0.998 |
10.01 |
39.64 |
64.09 |
68.66 |
Table 2: Selected soil chemical properties of the soil profile and composite surface soils of the study area
*OM = Organic matter; C: N = Carbon to nitrogen ratio; CEC = Cation exchange capacity; PBS = Percent base saturation
Applied N rate (kg ha-1) |
Total N available (%) |
Mean |
||||
0 |
0.070 |
0.068 |
0.066 |
0.067 |
0.069 |
0.068 |
25 |
0.075 |
0.070 |
0.072 |
0.075 |
0.073 |
0.073 |
50 |
0.074 |
0.074 |
0.069 |
0.074 |
0.071 |
0.072 |
75 |
0.078 |
0.073 |
0.075 |
0.078 |
0.076 |
0.076 |
100 |
0.073 |
0.071 |
0.073 |
0.073 |
0.074 |
0.073 |
Mean |
0.074 |
0.071 |
0.071 |
0.073 |
0.073 |
|
Table 3: Effects of different levels of applied N on total N of the soil after crop harvest
Parameters to be considered |
Mean squares for source of variation |
|
|
N (5) |
Error |
Stand count |
632.454545ns |
956.4527 |
Plant height (cm) |
609.4722258** |
4.5784523 |
Days to heading |
105.6525554** |
1.0576243 |
Days to maturity |
112.5477851** |
2.1624753 |
Grain filling period |
6.3647771ns |
3.0578231 |
Number of fertile tillers |
192750.254** |
7251.612 |
Number of spikes 2.4 m-2 |
23547.5671** |
1547.256 |
Spike length (cm) |
13.4586222** |
0.175421 |
Spikelets per spike |
10.8954234** |
0.194586 |
Thousand grain weight (g) |
84.2475621** |
2.5463218 |
Grain yield (kg ha-1) |
6547621.56** |
52761.52 |
Straw yield (kg ha-1) |
9754628.54** |
142357.24 |
Total biomass yield (kg ha-1) |
33591264.8** |
258653.51 |
Harvest index (%) |
0.0095468** |
0.0010458 |
Table 4: Mean square estimates for wheat agronomic parameters, yield and yield components as affected by application of N fertilizers
*Statistics in parentheses are values for degrees of freedom for respective source of variation; ** = Significant at P = 0.01: ns = Non-significant.
N (kg ha-1) |
Days to 50% heading |
Days to 50% maturity |
Grain filling (days) |
|
Effects of N fertilizer* |
|
|
0 |
89a |
152a |
56 |
25 |
86b |
145b |
54 |
50 |
83c |
139c |
54 |
75 |
78e |
139c |
55 |
100 |
80d |
135d |
55 |
LSD (0.05) |
0.92 |
1.62 |
Ns |
SE (±) |
0.37 |
0.52 |
0.53 |
CV (%) |
1.12 |
1.06 |
2.64 |
Table 5: Main effects of N on wheat phenology
*Means within a column sharing common letter(s) are not significantly different at P < 0.05; ns = Non significant; CV values of the respective parameters are main effects N fertilizer rates
N (kg ha-1) |
Stand count (number) |
Plant height (cm) |
Tillers 3m-2 |
|
Effects of N fertilizer* |
|
|
0 |
291 |
49.26d |
95d |
25 |
283 |
55.64c |
169c |
50 |
312 |
56.14c |
275b |
75 |
301 |
61.05b |
315b |
100 |
288 |
65.52a |
381a |
LSD (0.05) |
Ns |
1.32 |
63.51 |
SE (±) |
7.32 |
0.64 |
19.53 |
CV (%) |
9.56 |
3.57 |
26.54 |
Table 6: Main effects of N on wheat growth parameters
*Means within a column sharing common letter(s) are not significantly different at P < 0.05; ns =Non-significant; CV values of the respective parameters are main effects N fertilizer rates
N (kg ha-1) |
Spikes per 3 m2 |
Spike length (cm) |
Spikelets per spike |
|
Effects of N fertilizer* |
|
|
0 |
204d |
3.26d |
4.0d |
25 |
325c |
4.64c |
6c |
50 |
386b |
5.14b |
8b |
75 |
405b |
6.05a |
10a |
100 |
412a |
6.52a |
10a |
LSD (0.05) |
32.24 |
0.31 |
0.51 |
SE (±) |
6.35 |
0.14 |
0.53 |
CV (%) |
10.12 |
6.57 |
7.54 |
Table 7: The main effects of N fertilizers on wheat yield components
*Means within a column sharing common letter(s) are not significantly different at P < 0.05; ns = Non significant; CV values of the respective parameters are main effects N fertilizer rates
|
N |
GY |
SY |
TBY |
TGW |
HI |
SC |
PH |
DH |
DPM |
DGF |
FT |
SN |
SL |
SPS |
N |
1.00 |
0.95** |
0.89** |
0.92** |
0.801** |
0.08 |
0.13 |
0.90** |
-0.80** |
-0.85** |
0.00 |
0.76** |
0.61** |
0.88** |
0.77** |
GY |
|
1.00 |
0.94** |
0.93** |
0.81** |
0.27* |
0.18 |
0.80** |
-0.82** |
-0.77** |
0.15 |
0.72** |
0.67** |
0.80** |
0.68** |
SY |
|
|
1.00 |
0.92** |
0.71** |
-0.13 |
0.19 |
0.76** |
-0.85** |
-0.85** |
0.01 |
0.70** |
0.65** |
0.73** |
0.74** |
TBY |
|
|
|
1.00 |
0.72 |
0.02 |
0.17 |
0.85** |
-0.84** |
-0.82** |
0.04 |
0.78** |
0.72** |
0.85** |
0.75** |
TGW |
|
|
|
|
1.00 |
0.30* |
0.06 |
0.2* |
-0.78** |
-0.70** |
0.13 |
0.61** |
0.51** |
0.72** |
0.65** |
HI |
|
|
|
|
|
1.00 |
0.05 |
0.03 |
0.06 |
0.25 |
0.54* |
0.08 |
0.18 |
0.00 |
-0.02 |
SC |
|
|
|
|
|
|
1.00 |
0.02 |
-0.36 |
-0.37 |
0.06 |
0.20 |
0.57** |
0.15 |
0.15 |
PH |
|
|
|
|
|
|
|
1.00 |
-0.91** |
-0.92** |
-0.05 |
-0.74** |
0.55** |
0.86** |
0.73** |
DH |
|
|
|
|
|
|
|
|
1.00 |
0.96** |
-0.16 |
-0.73** |
-0.72** |
-0.30** |
-0.71** |
DPM |
|
|
|
|
|
|
|
|
|
1.00 |
0.18 |
-0.68** |
-0.48** |
-0.71** |
-0.63** |
DGF |
|
|
|
|
|
|
|
|
|
|
1.00 |
0.01 |
0.34* |
0.05 |
0.02 |
FT |
|
|
|
|
|
|
|
|
|
|
|
1.00 |
0.65** |
0.68** |
0.64** |
SN |
|
|
|
|
|
|
|
|
|
|
|
|
1.00 |
0.54** |
0.58** |
SL |
|
|
|
|
|
|
|
|
|
|
|
|
|
1.00 |
0.93** |
SPS |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1.00 |
Table 8: Correlation matrix of N fertilizer, crop yield and growth parameters
* = Significant at P = 0.05; ** = Significant at P = 0.01; N = Nitrogen rate; GY = Grain yield; SY = Straw yield; TBY = Total biomass yield; TGW = Thousand grain weight; HI = Harvest index; SC = Stand count; PH = Plant height; DH = Days to heading; DPM = Days to physiological maturity; DGF = Days to grain filling; FT = Fertile tiller per 3m2; SN = Spike number per 3m2; SL = Spike length; SPS = Spikelet per spike
N (kg ha-1) |
Thousand grain |
Grain yield |
Straw yield |
Total Biomass |
Harvest index (%) |
|
Effects of N fertilizer* |
|
|||
0 |
38.35c |
856.2e |
1134.0d |
2104.4e |
39.0b |
25 |
41.54c |
1097.6d |
1857.6c |
3043.5d |
35c |
50 |
45.14b |
1234.3c |
2661.8b |
4127.6c |
36c |
75 |
48.57a |
2154.4b |
2761.10b |
4857.7b |
45a |
100 |
49.35a |
2584.5a |
3576.30a |
6127.4a |
45a |
LSD (0.05) |
1.24 |
213.31 |
284.51 |
492.24 |
2.24 |
SE (±) |
0.45 |
74.14 |
112.53 |
174.35 |
1.35 |
CV (%) |
3.12 |
11.57 |
12.54 |
12.12 |
6.12 |
Table 9: Major effects of N on yield and harvest index of wheat
*Means within a column sharing common letter(s) are not significantly different at P < 0.05; ns = Non-significant; CV values of the respective parameters are main effects N fertilizer
N (kg ha-1) |
Grain N (%) |
Straw N (%) |
Grain N uptake |
Straw N uptake |
Total N uptake |
|
Effects of N fertilizer* |
|
|||
0 |
1.52 |
0.20e |
13.20 |
2.40 |
15.60 |
25 |
1.64 |
0.22 |
18.40 |
3.50 |
21.90 |
50 |
1.75 |
0.34 |
24.01 |
7.60 |
31.61 |
75 |
2.09 |
0.35 |
37.54 |
8.10 |
45.64 |
100 |
2.45 |
0.45 |
62.57 |
16.51 |
79.08 |
Table 10: Effects of applied N on grain and straw N contents and uptake parameters of wheat
N (kg ha-1) |
N |
|||
|
AR |
AE |
PE |
|
0 |
- |
- |
- |
|
25 |
27.13 |
12.05 |
41.18 |
|
50 |
40.05 |
15.02 |
38.08 |
|
75 |
53.24 |
19.15 |
33.36 |
|
100 |
67.21 |
21.63 |
28.17 |
|
Table 11: Effects of N fertilizer application on N apparent recovery, and agronomic and physiological efficiencies
AR = Apparent recovery (%); AE = Agronomic efficiency (kg grain per kg nutrient applied); PE = Physiological efficiency (kg grain per kg total nutrient uptake)
Tables at a glance