TABLE 1.
Toxicity of B. sphaericus technical powder, Cyt1A spore-crystal powder, and combinations of B. sphaericus and Cyt1A against A. aegypti
| Toxin(s) | No. tested | LC (μg/ml) of fourth-instar larvae (range)
|
Slope (standard error) | Synergism factor
|
||
|---|---|---|---|---|---|---|
| 50% | 95% | LC50 | LC95 | |||
| B. sphaericus (strain 2362) | ||||||
| 24 h | 500 | 266 (45.0–1,900) | 660,117 (19,904–385,589) | 0.5 | ||
| 48 h | 500 | 860 (636–1,320) | 19,791 (8,612–74,715) | 1.2 (0.14) | ||
| Cyt1Aa (fermentation 1) 24 h | 800 | 5.90 (2.86–12.0) | 133.9 (41.4–448) | 1.2 (0.21) | ||
| Cyt1Aa (fermentation 2) 24 h | 600 | 14.1 (6.63–30.0) | 136.5 (28.8–667) | 1.7 (0.31) | ||
| B. sphaericus + Cyt1A (3:1) | ||||||
| 24 h | 600 | 7.77 (6.96–8.67) | 25.8 (21.5–32.4) | 3.1 (0.23) | 2.9 | 20.4 |
| 48 h | 600 | 5.23 (1.58–17.3) | 22.8 (2.29–228) | 2.6 (1.0) | ||
| B. sphaericus + Cyt1A (10:1) | ||||||
| 24 h | 500 | 3.14 (2.84–3.47) | 7.76 (6.67–9.42) | 4.2 (0.32) | 15.6 | 172 |
| 48 h | 500 | 2.46 (0.399–15.6) | 5.36 (0.160–252) | 4.9 (1.2) | ||
| B. sphaericus + Cyt1A (20:1) | ||||||
| 24 h | 900 | 5.81 (4.98–6.86) | 47.7 (34.4–72.8) | 1.8 (0.13) | 14.3 | 52.2 |
| 48 h | 900 | 1.75 (1.45–2.12) | 40.0 (27.2–64.2) | 1.2 (0.07) | ||
| B. sphaericus + CytA (50:1) | ||||||
| 24 h | 700 | 8.29 (7.06–9.91) | 64.3 (44.4–106.9) | 1.8 (0.16) | 17.0 | 103 |
| 48 h | 700 | 3.17 (2.63–3.86) | 59.6 (39.2–102) | 1.3 (0.09) | ||