Autor(es): EJIOFOR, AO; OKAFOR, N

Resumo: Bacillus thuringiensis serotype H-14 spores and crystals, produced in 51 fermenters, were centrifuged and resuspended in emulsified palm olein to give 3.2 x 10(11) colony forming units (cfu)/ml. The suspension was mixed with a cassava-molasses-palm olein-charcoal (CMPC-2) mixture which served as the carrier, adhesive, dispersant and protectant. The final concentration of the formulation was 3.2 x 10(9) cfu/ml. The lethal concentrations capable of killing 50% of the test population (LC50) of CMPC-2 during 0,1 and 2 years of storage at 32 +/- 4-degrees-C were 0.056, 0.058 and 0.058 mg/ml respectively as against 0.054, 0.051 and 0.054 mg/ml for the Institut Pasteur Standard-1978 (IPS-78) during the corresponding period. The chi-2 tests showed that the results were homogeneous at P = 0.05. The relative potencies of the preparation were 964.3, 879.3 and 931 International toxic units (ITU) Aedes aegypti as compared with the 1000 ITU assigned to IPS-78. At 95% confidence limits there was no significant difference between the potencies of CMPC-2 and IPS-78. Field tests showed that CMPC-2 provided between 87.5 and 100% control of natural populations of Aedes spp. and Cutex spp. Sedimentation tests showed that CMPC-2 settled markedly during storage. This, therefore, required that the product be thoroughly shaken before use.

Imprenta: Journal of Applied Bacteriology, v. 71, n. 3, p. 202-206, 1991

Identificador do objeto digital: 10.1111/j.1365-2672.1991.tb04448.x

Descritores: Aedes aegypti - Larvicide

Data de publicação: 1991

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