Table 3.

Toxicity of Bacillus thuringiensis israelensis (IPS82) to 3rd instar Aedes aegypti larvae from laboratory colonies

					LC50a		LC90a
Samples	Origin	Temephos status	DEc	No. larvae	Mean (95% fiducial limits)	RRb	Mean (95% fiducial limits)	RRb
Rockefeller	USA	Susceptible	RF	1620	0.008 (0.007-0.009)	1.0	0.026 (0.021-0.036)	1.0
RecL	Recife-PE	Susceptible	No	1020	0.016 (0.012-0.020)	2.0	0.030 (0.026-0.039)	1.2
RecR	Araripina-PE	Highly resistant	Yes	1620	0.010 (0.009-0.012)	1.3	0.030 (0.025-0.040)	1.2

^aLethal Concentrations (mg/L) for 50% (LC₅₀) or 90% (LC₉₀) of larvae after 24 h.

^bResistance Ratio: LC for sample tested/LC for the Rockefeller reference (RF) colony.

^cIncrease of the activity of detoxifying enzymes (DE).