Table 1.
Toxicity of trypsin-activated Cry1Fa protein following various treatments administered to neonate larvae of S. frugiperda (measured after 5 days)a
| Protein | LC50 (ng/cm2) | 95% FL | Slope ± SEM |
|---|---|---|---|
| Nonpurified Cry1Fab | 51 | 25–131 | 0.9 ± 0.1 |
| Chromatography-purified Cry1Fab | 460c | 264–1,040 | 0.9 ± 0.1 |
| 127I-Cry1Fa (incubated with 10−6 M 127I-Na) | 255c | 155–509 | 1.6 ± 0.1 |
| 127I-Cry1Fa (incubated with 10−3 M 127I-Na) | >1,250 |
a
LC50, 50% lethal concentration; FL, fiducial limit at the 95% level.
b
Protein concentration was estimated by densitometry of Cry1Fa band in SDS-PAGE.
c
Differences between LC50 values were not statistically significant. The relative potency of purified Cry1Fa/127I-Cry1Fa was 1.4 (FL of 0.4 to 4.9).