What insects does bacillus thuringiensis kill
- •
Bacillus thuringiensis (Bt) in Brief
This fact sheet describes Bt used as a pesticide in sprays, granules, and other products. Bt crops are different. They're called "genetically engineered" or "transgenic" crops because they use DNA from Bt bacteria. The plants make Bt proteins (toxins) that only target specific insects.1 The Bt toxin made by the plant is called a "plant-incorporated protectant."
What is Bt?
Bt is a bacterium that is found naturally in soils throughout the world. To reproduce, Bt makes spores that grow into new bacteria. Bt spores have proteins that are toxic to insect larvae when eaten.2 Because Bt comes from a natural source, it is called a biopesticide. In general, biopesticides tend to pose fewer risks than typical human-made pesticides.
There are many types of Bt. Each type or strain affects different insect groups. Target insects include the beetle family, the fly family including mosquitoes, and the butterfly family. It is used to kill beetles and the larvae of mosquitoes, black flies, and moths.2,3,4Bt is also t
- •
Genetically engineered (modified) crops (Bacillus thuringiensis crops) and the world controversy on their safety
When a gene from one organism is transferred to improve or induce desired change in another organism, in laboratory, the result is a genetically engineered (or modified) organism (which may also called transgenic organism). There are different methods to transfer genes to animals and plants where the old and most traditional one is through the selective breeding. For example, a plant with a desired trait is selected and bred to produce more plants with such a trait. Recently, with the reached high technology, advanced techniques are carried out in laboratory to transfer genes that express the desired traits from a plant to a new plant (Martineau 2001).
The first produced genetically modified plant in the laboratory was tobacco in 1983 and was tested in 1986 as herbicide-resistant in France and the USA. In 1994, the European Union approved the commercial production of the plant as resistant to the herbicide bromoxynil (Martineau 2001).
Tomato was the first commercia
- •
Published in final edited form as: Nature. 2016 Apr 27;533(7601):58–63. doi: 10.1038/nature17938
Abstract
The Bacillus thuringiensis δ-endotoxins (Bt toxins) are widely used insecticidal proteins in engineered crops that provide agricultural, economic, and environmental benefits. The development of insect resistance to Bt toxins endangers their long-term effectiveness. We developed a phage-assisted continuous evolution (PACE) selection that rapidly evolves high-affinity protein-protein interactions, and applied this system to evolve variants of the Bt toxin Cry1Ac that bind a cadherin-like receptor from the insect pest Trichoplusia ni (TnCAD) that is not natively targeted by wild-type Cry1Ac. The resulting evolved Cry1Ac variants bind TnCAD with high affinity (Kd = 11–41 nM), kill TnCAD-expressing insect cells that are not susceptible to wild-type Cry1Ac, and kill Cry1Ac-resistant T. ni insects up to 335-fold more potently than wild-type Cry1Ac. Our findings establish that the evolution of Bt toxins with novel insect
Copyright ©vanflat.pages.dev 2025