Publications by authors named "C P DE Bortoli"
The resistance of pest insects to biopesticides based on the bacterium Bacillus thuringiensis (Bt) is normally associated with changes to the receptors involved in the mechanism of action of the pesticidal proteins produced by Bt. In some strains of Plutella xylostella (the diamondback moth) resistance has evolved through a signalling mechanism in which the genes encoding the receptor proteins are downregulated whereas in others it has been linked to structural changes in the receptors themselves. One such well characterized mutation is in the ABCC2 gene indicating that changes to this protein can result in resistance.
View Article and Find Full Text PDFThe fall armyworm (Spodoptera frugiperda) is a major global pest causing severe damage to various crops, especially corn. Transgenic corn producing the Cry1F pesticidal protein from the bacterium Bacillus thuringiensis (Cry1F corn) showed effectiveness in controlling this pest until S. frugiperda populations at locations in North and South America evolved practical resistance.
View Article and Find Full Text PDFThe fall armyworm (JE Smith) () is a polyphagous pest targeted by selected Cry and Vip3A insecticidal proteins from the bacterium (Bt) that are produced in transgenic Bt corn and cotton. Available evidence suggests that sublethal larval exposure to Cry1Ac increases flight activity in adult spp. However, it is not known whether this effect is also observed in survivors from generally lethal exposure to Cry1Ac.
View Article and Find Full Text PDFArticle Synopsis
- The fall armyworm (Spodoptera frugiperda) is a major pest affecting food and fiber crops, with resistance to Bt corn, which produces insecticidal proteins, being observed in both North and South America.
- Resistance to the Bt protein Cry1F is linked to genetic changes in a key protein called SfABCC2, which is crucial for the pest's susceptibility.
- Recent research identified a significant genomic deletion related to resistance in a Florida strain of S. frugiperda, marking the first time such a deletion has been connected to resistance against a Bt insecticidal protein.
Article Synopsis
- The evolution of resistance in pests poses a significant risk to the effectiveness and sustainability of Bt crops that produce insecticidal proteins.
- Monitoring for resistance to Cry and Vip3A proteins is essential to prevent further resistance development, with traditional methods involving bioassays currently in use.
- The study demonstrates that targeted DNA sequencing can effectively identify known and new resistance alleles in moth populations, improving monitoring efforts and revealing resistance alleles common to populations in different regions.