Table 2.
Variable loading scores of 16 selected global traits (12 root-related and four shoot traits) and the proportion of variation of each principal component
| Trait | PC1 | PC2 | PC3 | PC4 | PC5 |
|---|---|---|---|---|---|
| SRLZ1 | 0.60 | 0.67 | 0.03 | −0.21 | 0.21 |
| SRLZ2 | 0.52 | 0.66 | 0.06 | −0.07 | 0.06 |
| MRD | 0.62 | 0.72 | 0.04 | −0.18 | 0.18 |
| SRN | 0.26 | −0.36 | 0.42 | −0.25 | 0.09 |
| RL | 0.89 | 0.02 | 0.03 | 0.37 | 0.20 |
| RD | −0.34 | −0.53 | −0.09 | −0.02 | 0.36 |
| SRL | −0.34 | 0.50 | 0.38 | 0.65 | −0.14 |
| RLI | 0.59 | −0.50 | 0.01 | 0.55 | 0.10 |
| RTD | 0.46 | −0.22 | −0.25 | −0.69 | −0.19 |
| RM | 0.93 | − 0.18 | − 0.15 | 0.05 | 0.25 |
| SM | 0.91 | −0.24 | 0.20 | − 0.02 | − 0.08 |
| TDM | 0.95 | −0.22 | 0.06 | 0.01 | 0.05 |
| RMR | −0.19 | 0.07 | −0.70 | 0.14 | 0.54 |
| SH | 0.34 | −0.22 | 0.73 | −0.09 | 0.13 |
| LN | 0.59 | −0.01 | −0.35 | 0.14 | −0.55 |
| TN | 0.71 | −0.05 | −0.39 | 0.23 | −0.28 |
| Variation proportion | |||||
| Eigenvalue | 6.28 | 2.57 | 1.75 | 1.57 | 1.08 |
| Variance (%) | 39.3 | 16.2 | 11.0 | 9.8 | 6.7 |
| Cumulative variability (%) | 39.3 | 55.5 | 66.5 | 76.3 | 83.0 |
Rotation converged in 25 iterations using Varimax with Kaiser normalization. For each trait, the large variable loading score crossing the six components appears in bold. Three principal components with eigenvalues > 1 were extracted and considered significant (Tabachnik and Fidell, 1996)