Table 1.
Chlorophyll fluorescence, leaf temperature, gas exchange, and defense parameters in N. attenuata immediately after 1 d of herbivory by M. sexta on wild-type and JA defense-suppressed (asLOX) plants. Unless otherwise indicated, different letters denote differences among all treatments (simple effects) at the P≤0.05 level of significance. Leaf temperature denotes tissues of the same leaf directly adjacent to where herbivores fed (+) or did not feed (−). *P≤0.07; **0.07< P≤0.1. FW, Fresh weight
| Wild type | asLOX | |||
|---|---|---|---|---|
| − herbivore | + herbivore | − herbivore | + herbivore | |
| Chlorophyll fluorescence | ||||
| Propagated damage to F v/F m | ||||
| % of remaining leaf | 2.9±0.2a | 2.3±0.3b* | ||
| Total area (mm2) | 66±5a | 52±7b* | ||
| Propagated damage to F q'/F m' | ||||
| % of remaining leaf | 9.0±1.9a | 4.8±0.7a | ||
| Total area (mm2) | 206±44a | 109±16a | ||
| Leaf temperature (°C) | 23.1±0.2a | 22.3±0.3b* | 22.8±0.3ab | 22.1±0.1c* |
| Gas exchange | ||||
| CO2 assimilation (µmol m–2s–1) | 8.4±0.1a | 8.0±0.2b** | 8.4±0.1a | 8.1±0.3ab |
| Stomatal conductance (mmol m–2s–1) | 0.233±0.007a | 0.222±0.016a | 0.214±0.015ab | 0.181±0.012b* |
| Intercellular CO2 (C i) | 295±2a | 298±3a | 292±4a | 281±3b* |
| Respiration (µmol m–2s–1) | -0.63±0.06a | -0.66±0.09a | -0.47±0.05b | -0.55±0.05ab |
| Defense metabolites | ||||
| JA (nmol mg FW–1) | 51±6a | 107±15b | 49±4a | 58±5a |
| TPI (nmol mg protein–1) | 1.3±0.1a | 4.4±0.4b | 0.4±0.1c | 0.4±0.1c |
| Nicotine (mg g FW–1) | 0.58±0.04a | 0.61±0.03a | 0.43±0.02b | 0.38±0.03b |