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Bacillus thuringiensis is a Gram-positive, soil dwelling bacterium of the genus Bacillus. Additionally, B. thuringiensis also occurs naturally in the caterpillars of some moths and butterflies, as well as on the surface of plants.[1] Image File history File linksMetadata No higher resolution available. ...
For other uses, see Scientific classification (disambiguation). ...
Phyla/Divisions Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Omnibacteria Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular, bacterium) are a major group of living organisms. ...
Classes Bacilli Clostridia Mollicutes The Firmicutes are a division of bacteria, most of which have Gram-positive cell wall structure. ...
Orders Bacillales Lactobacillales The term bacilli (singular bacillus) is used to refer to any rod-shaped bacteria. ...
Families Alicyclobacillaceae Bacillaceae Caryophanaceae Listeriaceae Paenibacillaceae Planococcaceae Sporolactobacillaceae Staphylococcaceae Thermoactinomycetaceae Turicibacteraceae The Bacillales are an order of Gram-positive bacteria, placed within the Firmicutes. ...
Wikipedia does not have an article with this exact name. ...
Species Bacillus anthracis Bacillus cereus Bacillus coagulans Bacillus globigii Bacillus licheniformis Bacillus natto Bacillus subtilis Bacillus sphaericus Bacillus thuringiensis etc. ...
This article does not cite any references or sources. ...
Gram-positive bacteria are those that are stained dark blue or violet by gram staining, in contrast to gram-negative bacteria, which are not affected by the stain. ...
Phyla/Divisions Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Omnibacteria Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular, bacterium) are a major group of living organisms. ...
For other uses, see Genus (disambiguation). ...
Species Bacillus anthracis Bacillus cereus Bacillus coagulans Bacillus globigii Bacillus licheniformis Bacillus natto Bacillus subtilis Bacillus sphaericus Bacillus thuringiensis etc. ...
This article is about a form of an insect. ...
A moth is an insect closely related to the butterfly. ...
For other uses, see Butterfly (disambiguation). ...
B. thuringiensis was discovered 1901 in Japan by Ishiwata and 1911 in Germany by Ernst Berliner, who discovered a disease called Schlaffsucht in flour moth caterpillars. B. thuringiensis is closely related to B. cereus, a soil bacterium, and B. anthracis, the cause of anthrax: the three organisms differ mainly in their plasmids. Like other members of the genus, all three are aerobes capable of producing endospores.[1] Binomial name Bacillus cereus Frankland & Frankland 1887 Bacillus cereus is an endemic, soil-dwelling, Gram-positive, rod shaped, beta hemolytic bacteria that causes foodborne illness. ...
Binomial name Bacillus anthracis Cohn 1872 Bacillus anthracis is a Gram-positive, facultatively anaerobic, rod-shaped bacterium of the genus Bacillus. ...
Figure 1: Illustration of a bacterium with plasmids enclosed showing chromosomal DNA and plasmids. ...
An aerobic organism or aerobe is an organism that has an oxygen based metabolism. ...
An endospore is a dormant, tough, non-reproductive structure produced by a small number of bacteria from the Firmicute family. ...
Upon sporulation, B. thuringiensis forms crystals of proteinaceous insecticidal δ-endotoxins (Cry toxins: Bacillus thuringiensis Toxin Nomenclature) which are encoded by cry genes. Cry toxins have specific activities against species of the orders Lepidoptera (Moths and Butterflies), Diptera (Flies and Mosquitoes) and Coleoptera (Beetles). Thus, B. thuringiensis serves as an important reservoir of Cry toxins and cry genes for production of biological insecticides and insect-resistant genetically modified crops. A representation of the 3D structure of myoglobin, showing coloured alpha helices. ...
The order Lepidoptera is the second most speciose order in the class Insecta and includes the butterflies, moths and skippers. ...
Suborders Nematocera (includes Eudiptera) Brachycera Diptera (di - two, ptera - wings), or true flies, is the order of insects possessing only a single pair of wings on the mesothorax; the metathorax bears a pair of drumstick like structures called the halteres, the remnants of the hind wings. ...
For other uses, see Beetle (disambiguation). ...
Kenyans examining insect-resistant transgenic Bt corn. ...
Use in pest control
Spores and crystalline insecticidal proteins produced by B. thuringiensis are used as specific insecticides under trade names such as Dipel and Thuricide. Because of their specificity, these pesticides are regarded as environmentally friendly, with little or no effect on humans, wildlife, pollinators, and most other beneficial insects. The Belgian company Plant Genetic Systems was the first company (in 1985) to develop genetically engineered (tobacco) plants with insect tolerance by expressing cry genes from B. thuringiensis.[2][3] A representation of the 3D structure of myoglobin, showing coloured alpha helices. ...
It has been suggested that ovicide be merged into this article or section. ...
A cropduster spreading pesticide. ...
--59. ...
This article is about modern humans. ...
This article does not cite any references or sources. ...
A pollinator is the agent that moves pollen from the male anthers of a flower to the female stigma of a flower to accomplish fertilization or syngamy of the female gamete in the ovule of the flower by the male gamete from the pollen grain. ...
For most people, when they think of insects, they think of pests such as mosquitoes or tomato worms. ...
Plant Genetic Systems (PGS), since 2002 part of Bayer CropScience, is a biotech company located in Ghent, Belgium. ...
Shredded tobacco leaf for pipe smoking Tobacco can also be pressed into plugs and sliced into flakes Tobacco is an agricultural product processed from the fresh leaves of plants in genus Nicotiana. ...
B. thurigiensis-based insecticides are often applied as liquid sprays on crop plants, where the insecticide must be ingested to be effective. It is thought that the solubilized toxins form pores in the midgut epithelium of susceptible larvae. Recent research has suggested that the midgut bacteria of susceptible larvae are required for B. thuringiensis insecticidal activity.[4]
Bacillus thuringiensis serovar israelensis, a strain of B. thuringiensis is widely used as a larvicide against mosquito larvae, where it is also considered an environmentally friendly method of mosquito control. Bacillus thuringiensis subspecies israelensis, also known as Bti, is a biological control agent for larval mosquitoes. ...
To meet Wikipedias quality standards, this article or section may require cleanup. ...
For other uses, see Mosquito (disambiguation). ...
A larval insect A larva (Latin; plural larvae) is a juvenile form of animal with indirect development, undergoing metamorphosis (for example, insects or amphibians). ...
Mosquito control is the task of managing the population of mosquitoes to reduce their damage to human health, economies, and enjoyment of mosquito-ridden areas. ...
Genetic engineering for pest control
Kenyans examining insect-resistant transgenic Bt corn. Image File history File links Size of this preview: 329 × 599 pixelsFull resolution (715 × 1302 pixel, file size: 2. ...
Image File history File links Size of this preview: 329 × 599 pixelsFull resolution (715 × 1302 pixel, file size: 2. ...
Binomial name L. This article is about the legume. ...
this insect is a europian insect whcich is a pest to maize ...
Larvae are the plural of larva, juvenile form of animals with indirect development. ...
Image File history File links Size of this preview: 800 × 600 pixelsFull resolution (2048 × 1536 pixel, file size: 599 KB, MIME type: image/jpeg) File historyClick on a date/time to view the file as it appeared at that time. ...
Image File history File links Size of this preview: 800 × 600 pixelsFull resolution (2048 × 1536 pixel, file size: 599 KB, MIME type: image/jpeg) File historyClick on a date/time to view the file as it appeared at that time. ...
Usage In 2000 more than 115,000 square kilometers of Bt transgenic crops were grown, constituting 19% of the worlds GM crops. There is potential for Bt GM crops to take up 33% of the insecticide market. The current use of transgenic Bt crops reduces the number of chemical insecticide treatments by more than 7.7 million acres (31,000 km²) per year.
Advantages There are several advantages in expressing Bt toxins in transgenic Bt crops: i). The level of toxin expression can be very high thus delivering sufficient dosage to the pest, ii). The toxin expression is contained within the plant system and hence only those insects that feed on the crop perish, iii). The toxin expression can be modulated by using tissue-specific promoters, iv). The resistance is inherited in a stable and Mendelian fashion and v). The toxin gene can be integrated in the chloroplast genome and thus the possibility of gene transfer via pollen is eliminated.
Safety Bt crops appear to be safe for the farmers and for consumers. The toxin is insect specific and poses no known danger to humans, although the technology is too new for long-term studies to be available.[citation needed] Bt toxin is not inactivated by sun (as normal) and is present for a long time in the soil (see documentary). A recent study funded by the European arm of Greenpeace, while inconclusive, has shown the possibility of a slight but statistically meaningful risk of liver damage in rats.[6]
Problems The expression of the Bt gene can vary. For instance, if the temperature is not ideal this stress can lower the toxin production and make the plant more susceptible. More importantly, reduced late-season expression of toxin has been documented, possibly resulting from DNA methylation of the promoter.[7] DNA methylation is a type of chemical modification of DNA that can be inherited without changing the DNA sequence. ...
A promoter is a regulatory region of DNA located upstream (towards the 5 region) of a gene, providing a control point for regulated gene transcription. ...
Due to the constant exposure to the toxin an evolutionary pressure is created for resistant pests. Already, the Diamondback moth population is known to have adapted so that it now has a resistance to Bt in spray form.[8] There is also a hypothetical risk that for example, transgenic maize will crossbreed with wild grass variants, and that the Bt-gene will end up in a natural environment, retaining its toxicity. An event like this would have ecological implications, as well as increasing the risk of Bt resistance arising in the general herbivore population. Evolutionary pressure or selection pressure can be formalized as an external pressure applied to a process, thereby pushing that process in a distinct direction. ...
Binomial name Plutella xylostella Linnaeus, 1777 The Diamondback moth (Plutella xylostella) is a European moth that has since spread to North America. ...
Transgenic maize (corn) has been deliberately genetically modified to have agronomically desirable traits. ...
The term crossbreed or crossbred refers to a hybrid animal of two purebred parents created by means of crossbreeding. ...
As of 2007, a new phenomenon called Colony Collapse Disorder (CCD) is affecting bee hives all over North America. While its causes are still unknown, its link to the use of Bt resistant transgenic crops is causing concern among scientists.[9] A research group called Mid-Atlantic Apiculture Research and Extension Consortium published a report on 2007-03-27 that found no evidence that pollen from Bt crops is adversely affecting bees. However, the study only investigated short term exposure. Studies on long term exposure still need to be investigated to determine if it causes changes in bee behaviour.[10] A honey bee on a Geraldton Wax Flower. ...
The honeybee is a colonial insect that is often maintained, fed, and transported by farmers. ...
The Mid-Atlantic Apiculture Research and Extension Consortium (MAAREC), established in 1997, is a regional group focused on addressing the pest management crisis facing the beekeeping industry in the Mid-Atlantic Region of the United States[1]. A task force has been established with representation from the departments of agriculture...
Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ...
is the 86th day of the year (87th in leap years) in the Gregorian calendar. ...
Fighting resistance One method of reducing resistance is the creation of Non-Bt crop refuges to allow some non-resistant insects to survive and maintain a susceptible population. The refuge approach is required by legislation in some regions including the US and Europe. The aim is to encourage a large population of pests so that any genes for resistance are greatly diluted. This technique is based on the assumption that resistance genes will be recessive. It appears so far to be a successful method of delaying widespread resistance to Bt toxins.[11] Alternately, creating a mosaic GM crop expressing many different Bt toxins would have a greater chance of eliminating the entire pest population and thus eliminating resistance alleles.[12] To date, no planned extinction of an insect pest has been successful.[13][14] For other uses, see Extinction (disambiguation). ...
Orders Subclass Apterygota Archaeognatha (bristletails) Thysanura (silverfish) Subclass Pterygota Infraclass Paleoptera (Probably paraphyletic) Ephemeroptera (mayflies) Odonata (dragonflies and damselflies) Infraclass Neoptera Superorder Exopterygota Grylloblattodea (ice-crawlers) Mantophasmatodea (gladiators) Plecoptera (stoneflies) Embioptera (webspinners) Zoraptera (angel insects) Dermaptera (earwigs) Orthoptera (grasshoppers, etc) Phasmatodea (stick insects) Blattodea (cockroaches) Isoptera (termites) Mantodea (mantids) Psocoptera...
Carpet beetle larvae damaging a specimen of Sceliphron destillatorius in an entomological collection A pest is an organism which has characteristics that are regarded as injurious or unwanted. ...
References - ^ a b Madigan, Michael; Martinko, John (editors) (2005). Brock Biology of Microorganisms, 11th ed., Prentice Hall. ISBN 0-13-144329-1.
- ^ Höfte H, de Greve H, Seurinck J, Jansens S, Mahillon J, Ampe C, Vandekerckhove J, Vanderbruggen H, van Montagu M, Zabeau M (1986). "Structural and functional analysis of a cloned delta endotoxin of Bacillus thuringiensis berliner 1715". Eur J Biochem 161 (2): 273-80. PMID 3023091.
- ^ Vaeck M, Reynaerts A, Hofte A, Jansens S, De Beuckeleer M, Dean C, Zabeau M, Van Montagu M, Leemans J (1987). "Transgenic plants protected from insect attack". Nature 328: 33–37.
- ^ Broderick N, Raffa K, Handelsman J (2006). "Midgut bacteria required for Bacillus thuringiensis insecticidal activity". Proc Natl Acad Sci U S A 103 (41): 15196-9. PMID 17005725.
- ^ Jan Suszkiw (November 1999.). Tifton, Georgia: A Peanut Pest Showdown. Agricultural Research magazine. Retrieved on 2007-05-23.
- ^ Séralini, et al: New analysis of a rat feeding study with a genetically modified maize reveals signs of hepatorenal toxicty, Archives of Environmental Contamination and Toxicology, Springer Science, Published online 13 March 2007.
- ^ VDong, H. Z. and Li, W. J. (2007) Variability of Endotoxin Expression in Bt Transgenic Cotton. Journal of Agronomy & Crop Science; 193:21-29.
- ^ "Organic Mystery," Scientific American, December, 2006, p. 33, quote by Bruce Tabashnik of the University of Arizona. [1]
- ^ Latsch, Gunther. Are GM Crops Killing Bees?. Spiegel International. March 22, 2007. [2]
- ^ Dively, G.P. Summary of Research on the Non-Target Effects of Bt Corn Pollen on Honeybees. March 27, 2007. [3]
- ^ Bt Cotton Script - Australian Broadcasting Corporation's Science Show
- ^ Atkinson, H. Lecture: Engineering Resistance to Insects.
- ^ Judson, Olivia. A Bug's Death. New York Times. July 23, 2007. [4]
- ^ The Science Show. Controlling pests in cotton crops. May 13, 2006. [5]
Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ...
is the 143rd day of the year (144th in leap years) in the Gregorian calendar. ...
The Australian Broadcasting Corporation or ABC is Australias national non-profit public broadcaster. ...
See also The Western corn rootworm, Diabrotica virgifera, is a beetle. ...
External links - Bacillus thuringiensis Genome Projects (from Genomes OnLine Database)
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