Table 2.
Rates of N, P, and K fertilizer, total fertilizer cost (TFC), measured grain yield, partial factor productivity of added N (PFP), and added net benefit (ANB) for field-specific nutrient management provided by Rice Crop Manager (RCM), farmers’ fertilizer practice (FFP), and blanket fertilizer recommendation (BFR); historical grain yield reported by farmers (GYR); and target grain yield with RCM (GYT) across two seasons (kharif and rabi) and two years in Odisha, India.
| Parameter | Treatment or contrast | Kharif |
Rabi |
||
|---|---|---|---|---|---|
| 2014 | 2015 | 2013–2014 | 2014–2015 | ||
| Trials (n) | 84 | 24 | 39 | 62 | |
| N rate (kg ha–1)a | RCM | 103 ab | 106 a | 102 a | 98 a |
| FFP | 70 a | 81 ab | 101 c | 94 bc | |
| RCM–FFPc | 33*** | 25*** | 1 ns | 4 ns | |
| P rate (kg ha–1)a | RCM | 14 a | 12 a | 11 a | 14 a |
| FFP | 20 a | 18 a | 28 b | 24 b | |
| RCM–FFP | –6*** | –6** | –17*** | –11*** | |
| K rate (kg ha–1)a | RCM | 28 b | 34 b | 19 a | 27 ab |
| FFP | 39 a | 47 a | 47 a | 44 a | |
| RCM–FFP | –11*** | –12** | –28*** | –17*** | |
| TFC (US$ ha–1) | RCM | 88 a | 90 a | 78 a | 85 a |
| FFP | 70 a | 90 bc | 100 c | 85 b | |
| BFR | 90 a | 87 a | 96 a | 90 a | |
| RCM–FFP | 17*** | 0 ns | –22*** | –1 ns | |
| RCM–BFRd | –3 ns | 3 ns | –18*** | –5 ns | |
| BFR–FFPe | 20*** | –3 ns | –4 ns | 4 ns | |
| Grain yield (Mg ha–1) | RCM | 5.5 b | 4.8 a | 5.4 ab | 4.9 a |
| FFP | 4.7 ab | 4.2 a | 5.2 b | 4.4 a | |
| BFR | 5.2 b | 4.6 a | 5.0 ab | 4.7 a | |
| RCM–FFP | 0.8*** | 0.6*** | 0.3* | 0.5*** | |
| RCM–BFR | 0.3*** | 0.3 ns | 0.4*** | 0.2* | |
| BFR–FFP | 0.5*** | 0.3* | –0.2 ns | 0.3*** | |
| PFP (kg kg–1) | RCM | 54 a | 46 a | 54 a | 51 a |
| FFP | 73 b | 54 a | 61 a | 55 a | |
| BFR | 65 a | 56 a | 63 a | 59 a | |
| RCM–FFP | –19*** | –9 ns | –7 ns | –5 ns | |
| RCM–BFR | –11*** | –10 ns | –8* | –8* | |
| BFR–FFP | –8** | 2 ns | 2 ns | 3 ns | |
| ANB (US$ ha–1) | RCM–FFP | 150 b | 129 ab | 76 a | 110 ab |
| RCM–BFR | 65 a | 54 a | 106 a | 50 a | |
| Difff | 85*** | 75** | –30 ns | 60*** | |
| GYR (Mg ha–1)g | 4.6 b | 4.4 b | 3.7 a | 4.4 b | |
| Diff from FFP yieldh | –0.1 b | 0.2 b | –1.5 a | 0.0 b | |
| GYT (Mg ha–1) | 5.1 b | 4.9 b | 4.2 a | 4.9 b | |
| Diff from RCM yieldi | –0.5 b | 0.1 c | –1.2 a | 0.0 c | |
ns = not significant (P > 0.05). *, **, and *** indicate significance at the 0.05, 0.01, and 0.001 probability levels, respectively.
Fertilizer applied with BFR: N = 80 kg ha–1, P =17 kg ha–1, and K =33 kg ha–1.
Means within a row followed by the same lowercase letter are not different at P ≤ 0.05.
RCM–FFP = Difference between RCM and FFP.
RCM–BFR = Difference between RCM and BFR.
BFR–FFP = Difference between BFR and FFP.
Diff = Difference between RCM–FFP and RCM–BFR.
Number for trials: 2014 = 82, 2015 = 24, 2013–2014 = 39, and 2014–2015 = 60.
Diff from FFP yield = Difference between the historical grain yield reported by farmer (GYR) and the measured yield with FFP.
Diff from RCM yield = Difference between the RCM target grain yield (GYT) and the measured yield with RCM.