Methods
The experiment was laid out in a randomised complete block design with 6 levels of Treatment in 5 blocks, giving 30 observations. The design was balanced. GrainYield_tha, GrainsPerSpike and TGW_g were recorded as response variables. Data were analysed by 1-Factor ANOVA. Treatment means were separated by LSD at p < 0.05. All analyses were carried out in R 4.5.3, agricolae 1.3.7.
📐 1-Factor ANOVA (RBD)
📋 Analysis Results ▸ GrainYield_tha, GrainsPerSpike, TGW_g
| Variable | F value | p-value | CV% | Sig? |
|---|---|---|---|---|
| GrainYield_tha | 18.974 | 5.6e-07 | 5.66% | Yes ✓ |
| GrainsPerSpike | 16.444 | 1.7e-06 | 4.79% | Yes ✓ |
| TGW_g | 4.735 | 0.0051 | 2.04% | Yes ✓ |
Ho1: The means of all the replications are equal. Ho2: The means of all the levels of Treatment are equal.
Each effect is tested against the error mean square of its trait (Error, 20 df). A null hypothesis is rejected when p ≤ α = 0.05; the stars give the level reached.
| SoV | DF | GrainYield_tha | GrainsPerSpike | TGW_g |
|---|---|---|---|---|
| Replication | 4 | 0.156NS | 6.077NS | 0.521NS |
| Treatment | 5 | 1.352*** | 55.313*** | 3.409** |
| Error | 20 | 0.071 | 3.364 | 0.72 |
*** p<0.001 ** p<0.01 * p<0.05 NS p≥0.05 | Values are Mean Squares
For GrainYield_tha: Replication (MS = 0.156) was not significant (NS), so Ho1 is not rejected; Treatment (MS = 1.352) was significant at the 0.1% level (***), so Ho2 is rejected. The error mean square was 0.071. For GrainsPerSpike: Replication (MS = 6.077) was not significant (NS), so Ho1 is not rejected; Treatment (MS = 55.313) was significant at the 0.1% level (***), so Ho2 is rejected. The error mean square was 3.364. For TGW_g: Replication (MS = 0.521) was not significant (NS), so Ho1 is not rejected; Treatment (MS = 3.409) was significant at the 1% level (**), so Ho2 is rejected. The error mean square was 0.72.
| Treatment | GrainYield_tha | Grp (LSD) | GrainsPerSpike | Grp (LSD) | TGW_g | Grp (LSD) |
|---|---|---|---|---|---|---|
| N0 | 3.752 ± 0.311 | c | 32.98 ± 0.853 | d | 41.44 ± 0.695 | b |
| N40 | 4.524 ± 0.209 | b | 35.56 ± 0.789 | c | 41.98 ± 0.867 | ab |
| N80 | 4.852 ± 0.336 | ab | 38.56 ± 1.295 | b | 42.6 ± 0.711 | a |
| N120 | 5 ± 0.418 | a | 41.26 ± 2.126 | a | 41.7 ± 0.424 | ab |
| N160 | 5.162 ± 0.231 | a | 40.68 ± 2.611 | ab | 41.14 ± 1.178 | bc |
| N200 | 5.012 ± 0.176 | a | 40.54 ± 2.921 | ab | 40.16 ± 0.902 | c |
Mean ± SD of the observations; letters from the chosen method.
For GrainYield_tha, the highest mean was recorded by N160 (5.162); N200, N120 and N80 were statistically at par with it (sharing a letter). The lowest mean was recorded by N0 (3.752).
For GrainsPerSpike, the highest mean was recorded by N120 (41.26); N160 and N200 were statistically at par with it (sharing a letter). The lowest mean was recorded by N0 (32.98).
For TGW_g, the highest mean was recorded by N80 (42.6); N40 and N120 were statistically at par with it (sharing a letter). The lowest mean was recorded by N200 (40.16).
| Statistic | GrainYield_tha | GrainsPerSpike | TGW_g |
|---|---|---|---|
| F stat | 18.97*** | 16.44*** | 4.74** |
| p value | 5.61e-07 | 1.74e-06 | 0.005 |
| CD (LSD, 1%) | 0.48 | 3.3 | 1.53 |
| CD (LSD, 5%) | 0.35 | 2.42 | 1.12 |
| MSE | 0.071 | 3.364 | 0.72 |
| SE(m) | 0.12 | 0.82 | 0.38 |
| SE(d) | 0.17 | 1.16 | 0.54 |
| CV(%) | 5.66 | 4.79 | 2.04 |
| Cohen's F | 2.18 | 2.03 | 1.09 |
CV = 5.66% for GrainYield_tha: Excellent experimental precision (CV < 10%).
CV = 4.79% for GrainsPerSpike: Excellent experimental precision (CV < 10%).
CV = 2.04% for TGW_g: Excellent experimental precision (CV < 10%).
| Variable | Block | n | mean | sd | se |
|---|---|---|---|---|---|
| GrainYield_tha | R1 | 6 | 4.79 | 0.516 | 0.211 |
| GrainYield_tha | R2 | 6 | 4.863 | 0.657 | 0.268 |
| GrainYield_tha | R3 | 6 | 4.443 | 0.548 | 0.224 |
| GrainYield_tha | R4 | 6 | 4.723 | 0.649 | 0.265 |
| GrainYield_tha | R5 | 6 | 4.765 | 0.466 | 0.19 |
| GrainsPerSpike | R1 | 6 | 37.983 | 3.927 | 1.603 |
| GrainsPerSpike | R2 | 6 | 39.7 | 4.865 | 1.986 |
| GrainsPerSpike | R3 | 6 | 36.933 | 2.419 | 0.987 |
| GrainsPerSpike | R4 | 6 | 38.6 | 3.771 | 1.54 |
| GrainsPerSpike | R5 | 6 | 38.1 | 3.099 | 1.265 |
| TGW_g | R1 | 6 | 41.35 | 0.916 | 0.374 |
| TGW_g | R2 | 6 | 41.983 | 0.331 | 0.135 |
| TGW_g | R3 | 6 | 41.517 | 1.458 | 0.595 |
| TGW_g | R4 | 6 | 41.2 | 1.092 | 0.446 |
| TGW_g | R5 | 6 | 41.467 | 1.422 | 0.581 |
Significant treatment effects (p ≤ α): GrainYield_tha, GrainsPerSpike, TGW_g — Treatments differ significantly. Use letter groups to identify which groups differ.
CV% = 5.66 % ( GrainYield_tha ): Excellent experimental precision (CV < 10%).
Mean Separation: Fisher's LSD — Treatments sharing the same letter are not significantly different.
Block Efficiency (GrainYield_tha) = 116.4%: the RCB design was 16.4% more precise than a CRD of the same plots would have been (Gomez & Gomez relative efficiency). Blocks are effective.
Design: RBD · Block: Replication | α = 0.05
📊 Summary Stats ▸ GrainYield_tha, GrainsPerSpike, TGW_g
| Variable | Treatment | n | mean | median | sd | se | cv | min | max |
|---|---|---|---|---|---|---|---|---|---|
| GrainYield_tha | N0 | 5 | 3.752 | 3.71 | 0.311 | 0.139 | 8.285 | 3.45 | 4.24 |
| GrainYield_tha | N40 | 5 | 4.524 | 4.63 | 0.209 | 0.094 | 4.622 | 4.28 | 4.74 |
| GrainYield_tha | N80 | 5 | 4.852 | 4.82 | 0.336 | 0.15 | 6.918 | 4.56 | 5.38 |
| GrainYield_tha | N120 | 5 | 5 | 5.08 | 0.418 | 0.187 | 8.363 | 4.47 | 5.57 |
| GrainYield_tha | N160 | 5 | 5.162 | 5.29 | 0.231 | 0.103 | 4.471 | 4.83 | 5.34 |
| GrainYield_tha | N200 | 5 | 5.012 | 5.02 | 0.176 | 0.079 | 3.517 | 4.82 | 5.21 |
| GrainsPerSpike | N0 | 5 | 32.98 | 32.9 | 0.853 | 0.381 | 2.585 | 32.1 | 34.3 |
| GrainsPerSpike | N40 | 5 | 35.56 | 35.8 | 0.789 | 0.353 | 2.22 | 34.6 | 36.5 |
| GrainsPerSpike | N80 | 5 | 38.56 | 38.7 | 1.295 | 0.579 | 3.359 | 37.1 | 40.5 |
| GrainsPerSpike | N120 | 5 | 41.26 | 41.4 | 2.126 | 0.951 | 5.152 | 38.8 | 44.4 |
| GrainsPerSpike | N160 | 5 | 40.68 | 40.1 | 2.611 | 1.168 | 6.418 | 37.8 | 44 |
| GrainsPerSpike | N200 | 5 | 40.54 | 41.1 | 2.921 | 1.306 | 7.206 | 37.1 | 44.6 |
| TGW_g | N0 | 5 | 41.44 | 41.7 | 0.695 | 0.311 | 1.677 | 40.2 | 41.8 |
| TGW_g | N40 | 5 | 41.98 | 42 | 0.867 | 0.388 | 2.066 | 40.8 | 43.2 |
| TGW_g | N80 | 5 | 42.6 | 42.5 | 0.711 | 0.318 | 1.668 | 41.6 | 43.5 |
| TGW_g | N120 | 5 | 41.7 | 41.8 | 0.424 | 0.19 | 1.017 | 41.2 | 42.3 |
| TGW_g | N160 | 5 | 41.14 | 41.7 | 1.178 | 0.527 | 2.864 | 39.5 | 42.1 |
| TGW_g | N200 | 5 | 40.16 | 40.2 | 0.902 | 0.403 | 2.245 | 39.3 | 41.6 |
GrainYield_tha SW (ANOVA residuals) W=0.937, p=0.075
GrainsPerSpike SW (ANOVA residuals) W=0.984, p=0.926
TGW_g SW (ANOVA residuals) W=0.969, p=0.505
🎨 Advanced Plots ▸ GrainYield_tha, GrainsPerSpike, TGW_g
GrainYield_tha ▸ GrainYield_tha, GrainsPerSpike, TGW_g
GrainsPerSpike ▸ GrainYield_tha, GrainsPerSpike, TGW_g
TGW_g ▸ GrainYield_tha, GrainsPerSpike, TGW_g
📊 Basic Plots ▸ GrainYield_tha, GrainsPerSpike, TGW_g
📐 1-Factor ANOVA (LSD)
🔤 Mean Separation ▸ GrainYield_tha
| Rank span (p) | Means in range | Critical difference | Note |
|---|---|---|---|
| every pair | 2 to 6 | 0.352 | flat test — one critical difference for every comparison |
p is how many means the compared range CONTAINS, endpoints included — two neighbours give p = 2, the largest against the smallest gives p = k. A step-wise test raises the bar as p grows, because a wider range gives a large gap more chances to appear by luck alone. Fisher's LSD is flat — one value for every pair — which is why it separates the most. Two consequences worth knowing: at p = 2 Duncan and SNK equal Fisher's LSD exactly, and at p = k SNK equals Tukey HSD exactly. Both are identities, not coincidences.
| Comparison | Mean 1 | Mean 2 | Difference | Rank span (p) | Critical difference | Significant |
|---|---|---|---|---|---|---|
| N160 vs N0 | 5.162 | 3.752 | 1.41 | 6 | 0.352 | Yes |
| N200 vs N0 | 5.012 | 3.752 | 1.26 | 5 | 0.352 | Yes |
| N120 vs N0 | 5 | 3.752 | 1.248 | 4 | 0.352 | Yes |
| N80 vs N0 | 4.852 | 3.752 | 1.1 | 3 | 0.352 | Yes |
| N40 vs N0 | 4.524 | 3.752 | 0.772 | 2 | 0.352 | Yes |
| N160 vs N40 | 5.162 | 4.524 | 0.638 | 5 | 0.352 | Yes |
| N200 vs N40 | 5.012 | 4.524 | 0.488 | 4 | 0.352 | Yes |
| N120 vs N40 | 5 | 4.524 | 0.476 | 3 | 0.352 | Yes |
| N80 vs N40 | 4.852 | 4.524 | 0.328 | 2 | 0.352 | No |
| N160 vs N80 | 5.162 | 4.852 | 0.31 | 4 | 0.352 | No |
| N160 vs N120 | 5.162 | 5 | 0.162 | 3 | 0.352 | No |
| N200 vs N80 | 5.012 | 4.852 | 0.16 | 3 | 0.352 | No |
| N160 vs N200 | 5.162 | 5.012 | 0.15 | 2 | 0.352 | No |
| N120 vs N80 | 5 | 4.852 | 0.148 | 2 | 0.352 | No |
| N200 vs N120 | 5.012 | 5 | 0.012 | 2 | 0.352 | No |
| Group | Mean | Letter group |
|---|---|---|
| N160 | 5.162 | a |
| N200 | 5.012 | a |
| N120 | 5 | a |
| N80 | 4.852 | ab |
| N40 | 4.524 | b |
| N0 | 3.752 | c |
For GrainYield_tha, the highest mean was recorded by N160 (5.162); N200, N120 and N80 were statistically at par with it (sharing a letter). The lowest mean was recorded by N0 (3.752).
Statistical notes
References
Duncan DB (1955) Multiple range and multiple F tests. Biometrics 11: 1-42.
Fisher RA (1925) Statistical Methods for Research Workers. Oliver and Boyd, Edinburgh.
Gomez KA, Gomez AA (1984) Statistical Procedures for Agricultural Research, 2nd edn. John Wiley & Sons, New York.
Keuls M (1952) The use of the 'studentized range' in connection with an analysis of variance. Euphytica 1: 112-122.
R Core Team (2026) R: A Language and Environment for Statistical Computing, version 4.5.3. R Foundation for Statistical Computing, Vienna, Austria.
Tukey JW (1949) Comparing individual means in the analysis of variance. Biometrics 5: 99-114.