Search results for "cry toxins"
showing 5 items of 5 documents
ABCC transporters mediate insect resistance to multiple Bt toxins revealed by bulk segregant analysis
2014
[EN] Background: Relatively recent evidence indicates that ABCC2 transporters play a main role in the mode of action of Bacillus thuringiensis (Bt) Cry1A-type proteins. Mapping of major Cry1A resistance genes has linked resistance to the ABCC2 locus in Heliothis virescens, Plutella xylostella, Trichoplusia ni and Bombyx mori, and mutations in this gene have been found in three of these Bt-resistant strains. Results: We have used a colony of Spodoptera exigua (Xen-R) highly resistant to a Bt commercial bioinsecticide to identify regions in the S. exigua genome containing loci for major resistance genes by using bulk segregant analysis (BSA). Results reveal a region containing three genes fro…
Susceptibility to BT of wild lepidopteran species in Nature Reserve in Sicily
2010
A wide range of crop plants and trees have been transformed with genes derived from the soil bacterium Bacillus thuringiensis (Bt) to express insecticidal proteins (insect-resistant Bt plants). Whereas the adoption of Bt plants constitutes one of the most common uses of transgenic plants in agriculture, the environmental benefits and risks remain an issue. To preserve the natural reserve and their fauna UE proposed that in future the Member State specify a minimum separation distance of metres between fields of GM plants and nature reserves or to forbid cultivation of GM plant in particular area based on scientific data. Natural reserve in Sicily have many endemism and rare species so next …
Toxicity of several d-endotoxins of Bacillus thuringiensis against Helicoverpa armigera (Lepidoptera: Noctuidae) from Spain
2005
Abstract Toxicity and larval growth inhibition of 11 insecticidal proteins of Bacillus thuringiensis were evaluated against neonate larvae of Helicoverpa armigera, a major pest of important crops in Spain and other countries, by a whole-diet contamination method. The most active toxins were Cry1Ac4 and Cry2Aa1, with LC50 values of 3.5 and 6.3 μg/ml, respectively. At the concentrations tested, Cry1Ac4, Cry2Aa1, Cry9Ca, Cry1Fa1, Cry1Ab3, Cry2Ab2, Cry1Da, and Cry1Ja1, produced a significant growth inhibition, whereas Cry1Aa3, Cry1Ca2, and Cry1Ea had no effect.
Estudio de las bases de la resistencia a las proteínas insecticidas de bacillus thuringiensis en ostrinia nubilalis
2013
Ostrinia nubilalis (Hübner) es una de las plagas más devastadoras de los cultivos de maíz de Europa y Norte América, y a nivel económico la obtención de un control eficaz de esta plaga es un logro fundamental. En 1996, se permitió la comercialización de las plantas transgénicas que llevan insertado en el genoma un gen procedente de Bacillus thuringiensis (Berliner) (Bt) y que codifica para una proteína insecticida de las que esta bacteria produce en forma de cristales paraesporales (proteínas Cry). A partir de esta fecha, la adopción de los cultivos de maíz Bt que expresan en concreto la toxina Cry1Ab ha ido aumentando progresivamente en todo el mundo, con el resultado de que las pérdidas e…
Potential effects of transgenic cotton on soil ecosystem processes in Vietnam.
2008
This chapter concentrates on the potential effects of transgenic cotton on the soil ecosystem of three major cotton growing areas in Vietnam: the coastal lowlands region, the central highlands (eastern and western Truong Son Mountain Range) and the south-eastern region. Soils in these three regions are very different, so it will be necessary to assess the effects of transgenic cotton on typical soils from all three regions. The soils in the south-eastern region are Luvisols, Andosols and Acrisols. In the central highlands, the soils are mainly Luvisols, Rhodic Ferrasols and Haplic Acrisols. The soils in the coastal lowlands region are mainly delta soils, consolidated occasionally by grey li…