Table 1.
Effects of year, cultivar, and levels of NPK on dry matter accumulation (DMA, g plant–1) in different plant organs at different growth stages and on dry matter harvest index of maize.
| Treatments | At silking | At physiological maturity | Post-silking DM accumulation | HI (DM)† | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Leaf | Stalk | Total | Leaf | Stalk | Grain | Total | |||||
| Stem | Tassel | Stem | Other | ||||||||
| Year | |||||||||||
| Year 1 | 39.2a | 129.5a | 5.3a | 174.1a | 49.0a | 121.1a | 52.3a | 182.5a | 405.0a | 230.8a | 0.45a |
| Year 2 | 40.0a | 126.6a | 5.4a | 171.1a | 52.2a | 119.2a | 52.5a | 181.2a | 405.4a | 234.3a | 0.45a |
| Cultivar | |||||||||||
| P3522 | 44.3a | 140.1a | 2.8c | 187.1a | 53.7a | 135.5a | 50.9b | 188.6a | 428.7a | 241.6a | 0.44a |
| P3396 | 34.3c | 121.1b | 5.0b | 160.4b | 49.0b | 116.0b | 56.5a | 180.0b | 401.4b | 241.0a | 0.45a |
| Rajkumar | 39.0b | 123.0b | 8.3a | 170.4b | 49.6b | 108.9b | 49.8b | 177.1b | 385.4b | 215.0b | 0.46a |
| Levels of NPK | |||||||||||
| N100P30K30 (50% RDF) | 39.0b | 118.7d | 5.2c | 162.9c | 43.4c | 107.9cd | 51.4c | 168.9d | 371.6c | 208.7c | 0.46a |
| N150P45K45 (75% RDF) | 42.1ab | 130.0cd | 5.5bc | 177.7bc | 51.7b | 120.3bc | 53.3c | 197.2bc | 422.6b | 242.4b | 0.47a |
| N200P60K60 (100% RDF) | 44.3a | 151.1b | 5.9ab | 201.4a | 60.5a | 142.6b | 58.3b | 209.7b | 471.1a | 269.7ab | 0.45a |
| N250P75K75 (125% RDF) | 44.3a | 157.8a | 6.2a | 208.3a | 61.4a | 152.8a | 62.3a | 211.6a | 488.1a | 279.8a | 0.43a |
| N300P90K90 (150% RDF) | 43.8a | 156.1a | 6.2a | 206.1a | 55.4ab | 135.6b | 58.1b | 224.5a | 473.5a | 267.4ab | 0.48a |
| P60K60 (100% RDF–N) | 30.0c | 88.7e | 4.3d | 123.0d | 41.5c | 94.8de | 42.0d | 120.8e | 299.1d | 176.1d | 0.41a |
| N200K60 (100% RDF–P) | 41.8ab | 141.4bc | 6.0a | 189.3ab | 51.7b | 127.5abc | 53.7c | 199.4bc | 432.3b | 243.6b | 0.46a |
| N200P60 (100% RDF–K) | 39.8b | 128.9cd | 5.0c | 173.8bc | 53.6ab | 120.6bc | 52.9c | 189.2c | 416.3b | 244.5b | 0.46a |
| Control (–NPK) | 27.5c | 79.7e | 4.1d | 111.3d | 37.5c | 79.3e | 39.7d | 115.5e | 272.0d | 160.8d | 0.43a |
| Source of variation | |||||||||||
| Year | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns |
| Cultivar | ** | * | ** | ** | * | * | ** | * | * | * | ns |
| Levels of NPK | ** | ** | ** | ** | ** | ** | ** | ** | ** | ** | ns |
| Year × cultivar | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns |
| Year × levels of NPK | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns |
| Cultivar × levels of NPK | * | ** | ns | ** | ns | ns | * | * | ns | * | ns |
| Year × cultivar × levels of NPK | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns |
Year 1 and year 2 represent winter 2012–13 and 2013–14, respectively. Within year, cultivar, and levels of NPK, numbers followed by different letters indicate significant differences at p ≤ 0.05 (otherwise statistically at par). ns, non-significant (p > 0.05). *Significant at p ≤ 0.05. **Significant at p ≤ 0.01; Other = Tassel + cob + shank + husk; †HI (DM), Harvest Index (Dry Matter)