The aim of the present study was to assess the influence of phosphorus levels and phosphorus solubilizing fungi on yield and nutrient uptake by wheat. The dry matter production by wheat at tillering, ear emergence, and harvest was significantly higher with 90 kg P2O5 ha−1 and was at par with 60 kg P2O5 ha−1. Application of
Wheat (
Phosphorus is one of the most important major nutrients required for the growth and development of crop plants. It plays a vital role in virtually every plant process like photosynthesis, energy storage and transfer, stimulating root development and growth, giving plant rapid and vigorous start leading to better tillering in wheat, and encouraging earlier maturity and seed formation. It also has a significant role in sustaining and building up of soil fertility, particularly under intensive system of agriculture. But, Phosphorus is one of the most immobile, inaccessible, and unavailable nutrient present in the soil. Deficiency of soil phosphorus is one of the important chemical factors restricting plant growth in soils. Therefore, sufficient quantity of soluble form of phosphorus fertilizers is applied to achieve maximum plant productivity. However, the applied soluble forms of phosphatic fertilizers rapidly become unavailable to plants by conversion into inorganic P fractions that are fixed by chemical adsorption and precipitation. Similarly, organic P fractions are immobilized in soil organic matter [
Phosphorus solubilizing microorganisms (bacteria and fungi) enable P to become available for plant uptake after solubilization. Several soil bacteria, particularly those belonging to the genera
The experiment was conducted at the Instructional Farm, Rajasthan College of Agriculture, Udaipur, during
The zone possesses typical subtropical climatic conditions characterized by mild winters and moderate summers associated with high relative humidity during the months of July to September. The average annual rainfall of the region is 637 mm, most of which is received during the month of July to September. The mean weekly meteorological parameters recorded at agro-meteorological observatory, Rajasthan College of Agriculture, Udaipur, during cropping periods are presented in Figure
Climatic parameters of the experimental site during crop growing season.
In order to assess the physicochemical properties of the soil before commencement of the experiment, soil samples to the depth of 0–15 cm were drawn randomly from ten different places of the field and homogeneous composite sample was prepared. The soil sample was air dried under shade and then passed through 2.0 mm sieve and stored in labeled polythene bag before analysis. The physicochemical properties of the soil were presented in (Table
Physicochemical properties of experimental soil before start of the experiment.
Soil properties | Contents |
---|---|
Mechanical composition: | |
Sand (%) | 52.83 |
Silt (%) | 20.96 |
Clay (%) | 26.21 |
Texture class | Sandy clay loam |
Chemical properties: | |
pH (1 : 2, soil : water suspension) | 8.11 |
EC [dSm−1 (1 : 2, soil : water suspension)] | 0.83 |
Organic carbon (%) | 0.53 |
Available nitrogen (kg ha−1) | 292.42 |
Available phosphorus (kg ha−1) | 21.96 |
Available potassium (kg ha−1) | 624.00 |
The experimental field was ploughed by two cross-harrowing followed by planking to obtain a good soil tilth. The seeds of wheat (Raj. 3077) were sown in plots (5 m × 2.5 m) in a randomized block design with three replications with crop geometry (23 cm × 10 cm). Recommended doses of N and K (120 and 40 kg ha−1) were applied in all the plots including control. The sources used for applying nitrogen and phosphorus were urea and single super phosphate (SSP), respectively. Murate of potash (MOP) was used to supply K. Phosphorus application was made as per the treatment.
Half dose of nitrogen was applied as a basal dose and remaining half dose of nitrogen was applied, one month after sowing as top dressing. Full doses of phosphorous and potassium were applied at the time of sowing below the seed in furrows made with the help of hand hoe. Two manual weeding was done at one and two months after sowing to provide an ideal environment to the crop. First irrigation was given at the time of sowing; however, second, third, and fourth irrigation was given as the crop requirement and to maintain the optimum moisture level in the field.
Soil pH and EC were determined using 1 : 2.5 soil : water suspension whereas soil particles, soil texture, organic carbon, available nitrogen, phosphorus, and potassium were determined following standard methods of analysis [
The experimental data were statistically analyzed for analysis of variance and test of significance through the procedure appropriate to the randomized block design. The critical differences were calculated whereas “F” test was found significant as outlined by K. A. Gomez and A. A. Gomez [
Data presented in Table
Effect of levels of phosphorus and phosphorus solubilizing microorganisms on dry matter production and yield of wheat at different stages of growth.
Treatment | Dry matter production (q ha−1) | Yield (q ha−1) | |||
Phosphorus levels | Tillering | Ear emergence | Harvest | Grain | Straw |
Control | 4.09 | 24.63 | 77.18 | 36.75 | 40.43 |
30 Kg P2O5 ha−1 | 5.27 | 30.02 | 90.32 | 43.38 | 46.94 |
60 Kg P2O5 ha−1 | 5.94 | 34.47 | 98.61 | 47.60 | 51.01 |
90 Kg P2O5 ha−1 | 6.34 | 36.43 | 102.98 | 48.67 | 52.80 |
S.Em.± | 0.227 | 1.074 | 2.675 | 0.370 | 0.617 |
C.D. (5%) | 0.665 | 3.151 | 7.845 | 1.085 | 1.811 |
Inoculum | |||||
Noninoculation | 4.21 | 26.71 | 85.64 | 41.49 | 44.14 |
| 6.09 | 33.80 | 96.12 | 45.75 | 50.37 |
| 5.94 | 33.66 | 95.07 | 45.34 | 49.77 |
S.Em.± | 0.196 | 0.931 | 2.316 | 0.321 | 0.535 |
C.D. (5%) | 0.576 | 2.729 | 6.794 | 0.940 | 1.568 |
Data presented in Table
The data related to the interaction effect of levels of phosphorus and phosphorus solubilizing microorganisms on grain and straw yield are presented in Table
Interaction effects of levels of phosphorus and phosphorus solubilizing microorganisms on grain and straw yield of wheat.
Phosphorus levels | Inoculum | |||||
Grain yield (q ha−1) | Straw yield (q ha−1) | |||||
Noninoculation | Noninoculation | |||||
Control | 32.95 | 39.06 | 38.24 | 34.98 | 44.21 | 42.09 |
30 Kg P2O5 ha−1 | 40.10 | 45.21 | 44.84 | 42.11 | 50.06 | 48.65 |
60 Kg P2O5 ha−1 | 47.85 | 49.17 | 48.78 | 49.65 | 52.87 | 54.00 |
90 Kg P2O5 ha−1 | 48.07 | 49.56 | 49.48 | 52.32 | 55.33 | 54.32 |
S.Em.± | 0.641 | 1.069 | ||||
C.D. (5%) | 1.880 | 3.136 |
It is apparent from the data (Table
Effect of levels of phosphorus and phosphorus solubilizing microorganisms on nitrogen uptake at different stages of wheat growth.
Treatments | Nitrogen uptake (kg ha−1) | ||||
Phosphorus levels | Tillering | Ear emergence | Harvest | By grain | By straw |
Control | 9.599 | 49.377 | 67.874 | 53.607 | 14.267 |
30 Kg P2O5 ha−1 | 13.318 | 66.514 | 85.623 | 66.673 | 18.949 |
60 Kg P2O5 ha−1 | 15.317 | 77.387 | 96.988 | 75.178 | 21.809 |
90 Kg P2O5 ha−1 | 16.498 | 82.325 | 101.552 | 78.476 | 23.165 |
S.Em.± | 0.6498 | 2.3276 | 1.556 | 1.275 | 0.4669 |
C.D. (5%) | 1.9059 | 6.8267 | 4.565 | 3.3070 | 1.3692 |
Inoculum | |||||
Noninoculation | 10.479 | 56.250 | 78.213 | 61.968 | 16.245 |
| 15.542 | 75.564 | 94.003 | 72.556 | 21.447 |
| 15.028 | 74.888 | 92.174 | 71.189 | 20.985 |
S.Em.± | 0.5268 | 2.0158 | 1.348 | 0.9765 | 0.4043 |
C.D. (5%) | 1.6506 | 5.9121 | 3.953 | 2.8639 | 1.1858 |
Data presented in Table
Effect of levels of phosphorus and phosphorus solubilizing microorganisms on phosphorus uptake at different stages of wheat growth.
Treatments | Phosphorus uptake (kg ha−1) | ||||
Phosphorus levels | Tillering | Ear emergence | Harvest | By grain | By straw |
Control | 1.168 | 5.955 | 8.790 | 6.165 | 2.625 |
30 Kg P2O5 ha−1 | 1.732 | 8.646 | 12.385 | 8.522 | 3.863 |
60 Kg P2O5 ha−1 | 2.084 | 10.678 | 14.831 | 9.991 | 4.840 |
90 Kg P2O5 ha−1 | 2.270 | 11.492 | 15.472 | 10.484 | 5.087 |
S.Em.± | 0.0813 | 0.366 | 0.2589 | 0.1729 | 0.1043 |
C.D. (5%) | 0.2383 | 1.0735 | 0.7593 | 0.5070 | 0.3059 |
Inoculum | |||||
Noninoculation | 1.318 | 7.191 | 11.462 | 7.875 | 3.587 |
| 2.101 | 10.289 | 13.869 | 9.371 | 4.498 |
| 2.022 | 10.097 | 13.577 | 9.175 | 4.403 |
S.Em.± | 0.0704 | 0.317 | 0.2242 | 0.1497 | 0.0903 |
C.D. (5%) | 0.2064 | 0.930 | 0.6576 | 0.4391 | 0.2649 |
Data presented in Table
Effect of levels of phosphorus and phosphorus solubilizing microorganisms on potassium uptake at different stages of wheat growth.
Treatments | Potassium uptake (kg ha−1) | ||||
Phosphorus levels | Tillering | Ear emergence | Harvest | By grain | By straw |
Control | 5.624 | 27.856 | 67.309 | 14.862 | 52.447 |
30 Kg P2O5 ha−1 | 8.005 | 35.757 | 82.596 | 19.451 | 63.145 |
60 Kg P2O5 ha−1 | 9.347 | 42.762 | 94.221 | 22.276 | 71.945 |
90 Kg P2O5 ha−1 | 10.015 | 45.938 | 101.619 | 23.371 | 76.045 |
S.Em.± | 0.352 | 1.519 | 1.741 | 0.376 | 1.462 |
C.D. (5%) | 1.033 | 4.455 | 5.104 | 1.104 | 4.288 |
Inoculum | |||||
Noninoculation | 5.944 | 29.885 | 76.669 | 17.261 | 59.408 |
| 9.521 | 42.309 | 92.001 | 21.620 | 78.380 |
| 9.277 | 42.041 | 90.640 | 21.236 | 69.404 |
S.Em.± | 0.305 | 1.316 | 1.507 | 0.326 | 1.266 |
C.D. (5%) | 0.894 | 3.858 | 4.421 | 0.956 | 3.714 |
The data related to the interaction effect of levels of phosphorus and phosphorus solubilizing microorganisms on nitrogen and phosphorus uptake by wheat are presented in Table
Interaction effects of levels of phosphorus and phosphorus solubilizing microorganisms on nitrogen and phosphorous uptake by wheat.
Phosphorus levels | Nitrogen uptake (kg ha−1) | Phosphorus uptake (kg ha−1) | ||||
Inoculum | ||||||
Noninoculation | Noninoculation | |||||
Control | 41.02 | 58.22 | 61.58 | 4.37 | 6.76 | 7.37 |
30 Kg P2O5 ha−1 | 59.63 | 72.09 | 68.30 | 7.53 | 9.32 | 8.72 |
60 Kg P2O5 ha−1 | 72.08 | 79.19 | 75.27 | 9.62 | 10.57 | 10.04 |
90 Kg P2O5 ha−1 | 75.14 | 80.73 | 80.61 | 9.99 | 10.84 | 10.82 |
S.Em.± | 1.95 | 0.30 | ||||
C.D. (5%) | 5.72 | 0.88 |
The data on the performance of phosphorus levels revealed a significant positive relation of grain and straw yield with the increased phosphorus application (Table
Significant increasing trends of nitrogen uptake by wheat were recorded with increasing levels of phosphorus up to 60 kg P2O5 ha−1 (Table
Results presented in Table