Table 4.
Forward multiple regressions of P. lanceolata leaf traits on growth and consumption parameters of caterpillars of M. brassicae feeding on these plants.
| Source | Bioassay 1 | Bioassay 2 | ||||
|---|---|---|---|---|---|---|
| RGR | RCR | ECI | RGR | RCR | ECI | |
| Specific leaf area (SLA) | - | - | - | - | - | - |
| Leaf dry matter content (LDMC) | - | - | - | - | - | - |
| Leaf N concentration | - | - | - | - | +0.21** | - |
| Leaf P concentration | −0.22* | −0.31** | +0.16 | - | - | - |
| Leaf aucubin concentration | - | - | - | - | - | - |
| Leaf catalpol concentration | - | - | - | −0.18* | −0.20* | - |
| Model R2 (%) | 4.7 | 9.9 | 2.6 | 3.2 | 10.2 | - |
| F-value | 4.6* | 10.2** | 2.5 | 4.3* | 7.3*** | - |
| df | 1,93 | 1,93 | 1,93 | 1,129 | 2,128 | - |
Values are standard partial regression coefficients. Data for bioassays 1 and 2 (7- and 10-week old plants, respectively). Model fit (100 × R2), F-tests, and their degrees of freedom (df) are indicated at the bottom. Values in bold indicate significant effects (p < 0.05).
*
p < 0.05.
**
p < 0.01.
***
p < 0.001.
RGR, relative growth rate; RCR, relative consumption rate; and ECI, efficiency of conversion of ingested food.