TABLE 2.
Bombyx mori mortality after injection of vegetative cells of B. thuringiensis mutant strainsa
| Time after injection (h) | 407 Cry− ΔinhA
|
407 Cry− ΔinhA2
|
407 Cry− ΔinhA ΔinhA2
|
|||
|---|---|---|---|---|---|---|
| % Mortalityb | Pc | % Mortality | P | % Mortality | P | |
| 24 | 86 (43/50) | 0.317 | 90 (45/50) | 0.715 | 88 (44/50) | 1.0000 |
| 48 | 90 (45/50) | 0.204 | 96 (48/50) | 1.0000 | 88 (44/50) | 0.48 |
a
All experiments were carried out on immunized B. mori larvae. Each larva was vaccinated with 105 viable cells of E. coli strain TG1. Two days after immunization, the larvae were challenged with 18 to 20 cells of B. thuringiensis mutant strains. The same dose of wild-type cells caused 90 to 95% mortality. The control was injected with sterile water that caused 0% killing in all assays. Fisher's exact test was used to evaluate the significance of changes in mortality with respect to that caused by the wild-type strain.
b
Number of dead larvae/number of infected larvae.
c
P value was calculated by Fisher's exact test.