TABLE 1.
Toxicity of crystalline Cry1Ac for ROTH, UNSEL, and Cry1Ac-SEL populations of P. xylostella
| Strain | Form of toxin | LC50 (95% FL)a | Avg slope (SE) | RRb |
|---|---|---|---|---|
| ROTH | Crystalc | 0.0020 (0.0001–0.0085) | 0.69 (0.18) | |
| Spore-crystald | 0.0013 (0.0003–0.0039) | 0.85 (0.19) | ||
| NAT spore-crystalde | 0.0020 (0.0008–0.004) | 2.12 (0.53) | ||
| UNSEL | Crystal | 0.0880 (0.034–0.19) | 1.29 (0.24) | 44 |
| Spore-crystal | 0.0920 (0.03–0.2) | 1.23 (0.24) | 71 | |
| NAT spore-crystal | 0.1110 (0.0003–0.315) | 1.64 (0.61) | 55 | |
| Cry1Ac-SEL | Crystal | 2.33 (0.14–29.62) | 0.54 (0.22) | 1,170 |
| Spore-crystal | 3.60 (1.1–15.0) | 0.81 (0.24) | 2,770 | |
| NAT spore-crystal | 2.08 (0.56–6.01) | 0.64 (0.16) | 1,040 |
a
Expressed in micrograms per milliliter. At least 150 larvae (F11) were used in each experiment. LC50, 50% lethal concentration FL, fiducial limits.
b
Resistance ratio of 50% lethal concentrations for the UNSEL and Cry1Ac-SEL populations to those for the ROTH population.
c
Expressed in E. coli.
d
Expressed in B. thuringiensis IPS78/11 and applied as a spore-crystal mixture.
e
NAT, N-terminally activated toxin.