Table 1.
Tobacco Hornworm Feeding Assay on Wild-Type and acx1 Plants
| Experimenta | Genotype | Damaged Leaf PI-II (μg/mL) | Undamaged Leaf PI-II (μg/mL) | Larval Weight (g)b |
|---|---|---|---|---|
| 1 | Wild type | 225 ± 47 | 199 ± 66 | 0.99 ± 0.41 (n = 38) |
| acx1 | Not detectable | Not detectable | 3.45 ± 1.68 (n = 42) | |
| 2 | Wild type | 141 ± 73 | 151 ± 26 | 0.10 ± 0.04 (n = 38) |
| acx1 | 15 ± 24 | Not detectable | 0.19 ± 0.05 (n = 41) |
In experiment 1, 11 newly hatched larvae were placed on leaves of each of five separately potted 6-week-old plants of each genotype. In experiment 2, 60 newly hatched larvae were placed randomly on leaves of 20 4-week-old plants of each genotype. Larvae were allowed to move freely between plants of the same genotype. Experiments 1 and 2 were terminated 10 and 3 d after the start of the feeding trial, respectively. At that time, larvae were recovered from plants and their weight measured. Also, PI-II levels in damaged and undamaged leaf tissue were measured. PI-II data represent the mean ± sd of at least six independent measurements. The detection limit of the PI-II assay was ∼5 μg PI-II/mL leaf juice.
In both experiments, the weight of larvae grown on wild-type and mutant plants was significantly different at P < 0.001 (Student's t test).