Transgenic cotton

Torres JB, Ruberson JR, Whitehouse M (2009) Transgenic cotton for sustainable pest management. A review. In Lichtouse E (ed) Sustainable agriculture reviews, vol 1. Springer, pp 15-53. DOI 10.1007/978-1-4020-9654-9 4 Unibots. www.unibots.com... 

Expression of ERF3 and ERF4 from sugarcane and cotton, respectively, rapidly increases response to exogenous ethylene and ABA, salt, cold, and drought, whereas their overexpression in transgenic plants enhances tolerance to drought and osmotic stress. ... 

Glufosinate has a broad weed spectrum (little to no selectivity), and is therefore sometimes marketed along with genetically engineered glufosinate-resistant crops (cotton, canola, maize, and rice). While this raises some concern in some parts of the world, transgenic technology has been widely accepted in the western hemisphere. Nevertheless, neither... 

As previously noted in Table 1, the methodology of impact assessment was different for each crop. Pesticide reduction in transgenic herbicide tolerant soybean, for example, was predicted by a scenario in which glyphosate was substituted by mixes of alternative herbicides, while the reduction in herbicide tolerant cotton was calculated by comparing the pesticide use in the year 2000 with that of the year preceding cotton adoption. 

A consistent difference of -78% for pesticide use and environmental impacts between non transgenic- and transgenic, insect resistant- cotton is observed. This consistency relates to the fact that the same insecticides were assumed to have been applied to both non transgenic and transgenic cotton, the impact being caused by different numbers of insecticide sprays that had been applied to these crops. The consistent difference of -100% observed for the impacts of insect resistant maize relates to the feet that Gianessi et al. [7] assumed that this transgenic maize would provide 100% control of European com borer. 

Non transgenic, (partially) insect resistant cotton varieties. Examples are ... 

To date over 30 plant terpenoid synthases have been cloned as cDNAs, and many of these were found to encode enzymes of secondary metabolism (43). Isolation and analysis of six genomic clones encoding monoterpene ((—)-pinene and (—)-limonene), sesquiterpene ((E)-a-bisabolene and S-selinene) and diterpene (abietadiene) synthases from Abies grandis, and a diterpene (taxadiene) synthase from Taxus brevifolia have been reported (44). Overexpression of a cotton farnesyl diphosphate synthase (EPPS) in transgenic Artemesia annua has resulted in 3- to 4-fold increase in the yield of the sesquiterpenoid anti-malarial drug, artemisinin, in hairy roots (45). 

Although the benefits of transgenic crops to consumers are somewhat abstract, as the level of agrochemical residues on crops is already very low, the benefits to farmers include higher profitability as a result of reduced chemical input and reduced toxic exposure. For example, farmers in some nations experienced a 75% reduction in exposure to the toxic effects of agrochemicals when growing transgenic cotton (46). Reductions in chemical exposure are clearly beneficial to the farmer, farm workers, and wildlife. 

The use of genetically modified corn and cotton has increased over 10-fold from 1992 to 1999 and as of 2002, 50 crop species have been evaluated for uses by the US Food and Drug Administration (FDA). In the development of transgenic crops, genes isolated from several varieties of the bacterium. Bacillus thuringienses (Bt) are probably the best known and most often cited example of GMO development. 

Many of the new transgenic crops (36%) are crops engineered to be resistant to old herbicides.331 These include bromoxynil (11.65) (TD50 111 mg/kg oral, mice) for cotton, and glyphosate for maize, cotton, and soybeans.332... 

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