Susceptibility of Different Instars of <I>Earias vittella</I> (Fabricius) to <I>Bacillus thuringiensis</I> Insecticidal Proteins

P. S. Shanmugam; R. Balagurunathan; N. Sathiah; N. G. V. Rao

doi:10.18311/jbc/2007/3852

Authors

P. S. Shanmugam
Department of Agric. Entomology, Tamil Nadu Agricultural University, Coimbatore-641003, Tamil Nadu
R. Balagurunathan
Department of Agric. Entomology, Tamil Nadu Agricultural University, Coimbatore-641003, Tamil Nadu
N. Sathiah
Department of Agric. Entomology, Tamil Nadu Agricultural University, Coimbatore-641003, Tamil Nadu
N. G. V. Rao
Department of Biotechnology, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola-444104, Maharashtra

DOI:

https://doi.org/10.18311/jbc/2007/3852

Keywords:

Bacillus thuringiensis, Earias vittella, Insecticidal Proteins, Median Lethal Concentration, Toxicity.

Abstract

The susceptibility of different instars of Earias vittella (Fabrieius) to Bacillus thuringiensis (Bt) insecticidal proteins (ICP) was studied. The LC₅₀ of CrylAa, CrylAb, Cry1Ac, CryiC and Cry1E were 108.54, 97.04, 66.62, 1240.83 and 1335.60 ng/cm², respectively to E. vittella neonates. The order of toxicity of different ICPs to second and third instar was Cry1Ac > CrylAb > CrylAa. Overlap 95 per cent fiducial limits at LC₅₀ of CrylAa and CrylAb showed similar toxicity of these toxins to second and third instars of E. vittella. The possibility of these toxins and toxicity parameters in resistance management is discussed.