The analysis clearly revealed sex- and dose-dependent effects on the kidney and liver of the treated rats. In addition, it should be taken into account if there are combination effects with other compounds in the food (Mesnage et al. The Cyt toxin (or protein) derived its name from being cytolytic to a wide range of invertebrate and vertebrate cells in vitro. ; Schnepf, E.; Baum, J.; Bravo, A. and Dean, D.H. 2014. 2008). Non-GMO means non-genetically modified organisms. For cotton growers, there was a lot of pressure from pests before the introduction of Bt cotton. Duan et al. Dorcester: PG Economics LTD. Online: www.pgeconomics.co.uk/pdf/2017globalimpactstudy, Chakroun M, Banyulls N, Bel Y, Ferre J (2016) Bacterial vegetative insecticidal proteins from entomopathogenic bacteria. http://nonaumorattoire.fr/english.htmnonaumoratoire.free.fr/english.htm: www.utcrops.com/cotton_insects/pubs/Wi29-Btcotton, http://creativecommons.org/licenses/by/4.0/, https://doi.org/10.1186/s41938-018-0051-2. Science 327(5972):1439, Article  These proteins are highly toxic to certain coleopteran species (Chakroun et al. Two classes of Vip toxins were described. In the USA, however, the total area of cotton was 4 million ha and out of which 3.2 million ha (80%) were combined Bt and herbicide-tolerant cotton (James 2016). 2001). They help in controlling soil pollution as the use of synthetic pesticides is reduced. 6(4):1222–1243, Bravo A, Gill SS, Soberon M (2007) Mode of action of Bacillusthuringiensis cry and Cyt toxins and their potential for insect control. The results of the reassessment indicated that in vitro studies Bt toxins were unstable in the presence of digestive fluids of human’s gut and were degraded in such fluids within 0–7 min. 2015) and is used for feeding livestock and as row material for the starch industry. This left a famine-stricken population without food aid. They found that the total mortality in larvae was significantly higher (57%) than in the untreated control (30%). The percentage of farmers reporting medium or severe damage to Bt corn from B. fusca rose from 2.5% in the 2005–2006 growing season to 58.8% in the 2007–2008 season. Benefits and Future J Pharmacy Res 6:879–883, Rettner R (2017) DNA: definition, structure and discovery. In the 1980s, the use of Bt increased worldwide when insects became increasingly resistant to the chemical insecticides (Milner 1994). The Cry toxin becomes active by proteoletic enzymes in the alkaline gut juice (pH 8–10). However, French government applied a principle of precaution against genetically modified crops. The study revealed no chronic, long-term effects of Bt cotton on such natural enemies. “Plant Genetic Systems”, in Belgium, was the first company to produce a Bt crop (tobacco) in laboratory in 1985 but the crop was not commercially successful (Vaek et al. They accused the Romeis group of using a different test method and this method was the reason for the difference in the results. 1st international symposium on biol. Designing genes for insertion, but once a gene has been isolated and cloned (amplified in a bacterial vector), it must undergo several modifications before it can be effectively inserted into a plant. Other effects were also noticed in the heart, adrenal glands, spleen, and hematopoietic system. Currently, available Bt cotton varieties produce either or both Cry toxins and Vip toxins that target specific caterpillar pests such as beet armyworm, Spodoptera exigua; cotton bollworm, Helicoverpa armeigera; and tobacco budworm, Heliothis virescens. Bt crops, containing Bt toxins, were planted in almost 100 million ha (Brookes and Barfoot 2017). Pest Control 28(23):1–6, Naranjo SE (2005) Long term assessment of the effects of transgenic Bt cotton on the abundance of non-target arthropod natural enemies. must begin by clarifying that all the plants that are grown today in the world have been modified by the man using different mechanisms that allow them to select characteristics according to their needs Google Scholar, Bagla P (2010) Hardy cotton-munching pests are latest blow to GM crops. 2007. Microbiol Mol Biol Rev 62(3):807–813, PubMed  However, a conventionally bred variety with longer shelf-life prevented the product from becoming profitable. 1992). Lu et al. Field-evolved resistance of S. frugiperda to Bt corn producing Cry1F occurred in 4 years in Puerto Rico, USA (Matten et al. Proceedings of the National Academy of science (PNAS) 98:11937–11943, Seralini GE, Cellier D, de Vendomois JS (2007) New analysis of a rat feeding study with a genetically modified maize reveals signs of haepatorenal toxicity. Nature 399:214, Lu YH (2010) Mirid bug outbreaks in multiple crops correlated with wide scale adoption of Bt cotton in China. http://www.scq.ubc.ca/bt-corn-is-it-worth-the-risk, pp 1–3, Hammond BG, Jes JM (2011) Impact of food processing on the safety assessment for proteins introduced into biotechnology- derived soybean and corn crops. It would bring no new knowledge that could reduce the hypothetical risks that could be generated by the cultivation and the consumption of GM Bt maize. Cry toxins had a good run and will hang on for a while longer, but the era of the Cry toxins seems to be ending. J Agric Food Chem 59:5842–5851, Naud, M.; Krivine, J.; Houdebine, L.M. 1982). The examination of their guts showed that no recombinant DNA was found (Netherwood et al. Egyptian Journal of Biological Pest Control, https://en.wikipedia.org/wiki/genetically_modified_food_controversies, http://en.wikipedia.org/wiki/Genetically_modified_maize, http://www.gmocompass.org/eng/grocery_shopping/crops/18.genetically_modified_, www.pgeconomics.co.uk/pdf/2017globalimpactstudy, http://link.springer.com/chapter/10.1007/978-3-319-56678_3.pdf, www.btnomencluture.infolifesci.sussex.ac.uk/Home/Neil_Crickmore/Bt, http://naturalociety.com/merck-monsanto-worst-company-award, http://www.scq.ubc.ca/bt-corn-is-it-worth-the-risk. As a solution for this problem the company produced another Bt cotton expressing Cry1Ac + Cry1Ab (Bagla 2010). Science 328:1151–1154, Lu YH, Kongming W, Yuying J, Yuyuan G, Nicolas D (2012) Widespread adoption of Bt cotton and insecticide decrease promotes biocontrol services. Bacillus thuringiensis is a gram-positive, spore-forming bacteria which is mainly found in the soil. By introducing the toxin-gene into the plant, the structure of the toxin is modified and may cause its selectivity to be changed. Nat Biotechnol 22(2):204–209, Onose J, Imai T, Hasumura M, Ueda M, Ozeki Y, Hirose M (2008) Evaluation of subchronic toxicity of diatery administered Cry1Ab protein from Bacillus thuringiensis in male rats with chemically induced gastrointestinal impairment. In addition, there are still scientists as well as crops producers worldwide that do not trust in the biological control of insects. Crystal of Bt kurestaki and Bt israelinsis “From Hofte and Whitely (1989)”. Zakharyan (1979) reported the presence of a plasmid in a strain of Bt and suggested that the plasmids involved in formation of endospore and crystal. In: Romois J, Shelton AM, Kennedy GG (eds) Integration of insect resistant genetically modified crops within IPM programs. Hofte and Whitely (1989) termed these “cry genes” and the protein they encode “cry proteins” (for crystal) and cyt proteins (for cytolytic). Mezzomo et al. 1), but the activity of the crystal was not then discovered (Milner 1994). The toxins released by the plant would paralyze the guts of the caterpillar, when they feed on the plants. Bacillus thuringiensis (or Bt) is a Gram-positive, soil-dwelling bacterium, commonly used as a biological pesticide. In January 2005, the Hungarian government announced a ban on importing and planting of GM maize seeds, which was subsequently authorized by the European Union (James 2016). DNA (deoxyribonucleic acid) is a very large molecule that carries the genetic instructions used in growth, development, functioning, and reproduction of all living organisms and many viruses. CAS  http://en.wikipedia.org/wiki/Genetically_modified_maize, pp 1–6, Anonymous (2012) Genetically modified maize in Europe. Nature 487:362–365, Luthy P, Cordier J, Fischer H (1982) Bacillus thuringiensis as a bacterial insecticide: basic considerations and application. (2013) compared sweet corn varieties grown in the USA where the primary insect pest was Heliothis zea and demonstrated that non-sprayed Bt varieties produced more clean marketable ears than corn varieties sprayed with chemical insecticides up to 8 times. Ecol Entomol 30:307–315, Losey JE, Rayor LS, Carter ME (1999) Transgenic pollen harms monarch larvae. In addition, a review by Food Standards Australia New Zealand of the 2009 Vendomois et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. PubMed  It was then representing 85% of the total area of corn in USA, 84% in Canada, 83% in Argentina, 57% in South Africa, 36% in Brazil, 20% in Spain, and 19% in Philippines (James 2016). Agric Ecosyst Environ 49:9–13, Moar WJ, Eubanks M, Freeman B, Head G (2004) Effects of Bt cotton on biological control agents in the southeastern United States. Transforming plants, which is the heritable change in a cell or organism brought about by the uptake and establishment of introduced DNA. They concluded that there were no adverse effects on non-target arthropods (parasitoids and predators) in Bollgard cotton fields compared to conventionally grown cotton ones. PubMed Central  2009). The Bt cotton variety is genetically transformed with the Bt gene to protect the plants from bollworm, a major pest of cotton. If an insect had an allele to survive on toxin 1, it probably does not have different alleles to survive on toxins 2 and 3 (Anonymous 2016). In 2001, the Environmental Protection Agency (EPA) in the USA supervised comprehensive studies to reassess the 4 registered Bt crops that had been accepted for agricultural use since 1995. Others, however, are against Bt crops as they may cause risk to human. A study in University of California revealed that the average cost reduction in pesticides applied in Bt cotton fields from 1996 to 1998 was between 25 and 65 dollars per acre; the yield estimated, in the same period, was 5% more, on average, than the traditional cotton. Since 1996 plants have been modified with short sequences of genes from Bt to express the crystal protein Bt makes. However, in spite of the notable increase in the available information, studies on the long-term health effects of GM plants, including tests of mutagenicity, teratogenicity, and carcinogenicity seem to be still clearly necessary. Calgene took the initiative to obtain the Food and Drug Administration (FDA) approval for its release in 1994. Only plants expressing the selectable marker gene will survive and possess the transgene of interest. A 6-year field study assessed the long-term impact of Bt cotton producing Cry1Ac toxin on 22 species and strains of foliar-dwelling natural enemies in Arizona (Naranjo 2005). Egypt J Biol Pest Control 28, 52 (2018). Bollgard II was introduced in 2003 representing the next generation of Bt cotton. In the field, no significant adverse effects on … In 2016, the world total area of cotton was 35 million ha (in 18 countries), out of which 22.3 million (64%) were GM cotton. Minor variations were designated by lowercase letters (a, b, c…. Microbiologia 48(2):226–229, Department of Biological Control, Plant Protection Research Institute, Dokki, Giza, Egypt, You can also search for this author in There are rules in Europe countries that all food products made from Bt corn must be labeled. Environ Sci Eur 24:10, Hilbeck A, Moar W, Pusztai-Garet M, Bigler F (1998) Toxicity of Bacillus thuringiensis Cry1Ab toxin to Chrysoperla carnea. Arch Environ Cotam Toxicol 52(4):596–602, Shelton AM, Olmstead DL, Burkness EC, Hutchison WD, Dively G, Welty C (2013) Multi-state trials of Bt sweet corn varieties for control of the corn earworm. Bt crops are plants genetically engineered (modified) to contain the endospore (or crystal) Bt toxin to be resistant to certain insect pests. (2013) reported that Bt spore preparations containing various Cry proteins were found to cause hemato-toxocity in mice when administered by oral gavage. It leads to more productivity in a small area of land. None were detected in the liver, spleen, or lymph nodes indicating that they were too large to be systematically absorbed from the GI tract (Chowdhury et al. When the bacterial DNA is integrated into a plant chromosome, it effectively hijacks the plants’ cellular machinery and uses it to ensure the proliferation of the bacterial population. Genetic Engineering Appraisal Committee (GEAC) Hall (2011) mentioned that the risks of Bt foods to human health appear small based on what is known about the bacterial endotoxin, its specificity and confidence of the process of plant transformation and screening. The insecticidal active toxin presents in Bt maize has been exploited for decades within the applied commercial compounds of Bacillus thuringiensis without any observed toxicity or allergic response (Naud et al. www.livescience.com/37247-dna, p 3, Roh JY, Choi JY, Li MS, Jin BR, Je YH (2007) Bacillus thuringiensis as a specific, safe and effective tool for insect control. Also, significantly more larvae died (29%) when received Cry1Ab later during their development compared to the control ones (17%). The crop was produced to resist the infestation by the European corn borer, Ostrinia nubilalis, but later in the 2000s, it has been produced against the corn earworm, H. zea, and the corn rootworm, Diabrotica virgifera in addition to O. nubilalis (James 2016). It can easily feed an increasing population due to increased yields in a short time. Monsanto, a major biotech corporation responsible for genetically modified foods, has been given “the Worst Company of 2011 Award” for threatening both human health and the environment. Feeding the 2nd instar larvae on pure Bt toxins mixed with their food on concentrations far above those to which they would be exposed showed insignificant mortality rate between the treated larvae and the control group. Similarly, the continuous cultivation of Bt cotton caused obvious infestation by aphids and mealybugs in India (Losey et al. The Germany’s Environment Minister issued a ban for cultivation of Bt maize in April, 2009, after published laboratory findings in Germany indicating that A. bipunctata larvae can be harmed by Bt toxins (Schmidt et al. Exploring selection for Bt resistance in heliothines: results of laboratory and field studies. It consists of two long nucleotide chains. All groups had detectable levels of the toxin in blood, including 93% of pregnant women and 80% of fetuses at concentrations of 0.19 ± 0.30 and 0.04 ± 0.04 ng/ml, respectively (Anonymous 2010). Part of Toxins 6:3296–3325, Rani SJ, Usha R (2013) Transgenic plants: types. Bt gene was discovered by Ernst Berliner. In 1994, the European Union approved the commercial production of the plant as resistant to the herbicide bromoxynil (Martineau 2001). b Crystal of Bt kurestaki. Food Chem Toxicol 95:12–18, Duan JJ, Marvier M, Huesing J, Dively G, Huang ZY (2008) A meta-analysis of effects of Bt toxins on honeybees. CAS  The Cyt toxins are also formed during sporulation and occur within the parasporal body but in a separate inclusion. For more and recent information about nomenclature of Bt toxins, see Crickmore (2017). In February 2012, the Hilbeck’s group published a further study (Hilbeck et al. Environ Entomol 27:1255–1263, Hofte H, Whitely HP (1989) Insecticidal crystal proteins of Bacillus thuringiensis. 2013). Control of arthropods, Honolulu, Moussa S, Baiomy F, Abouzaid K, Nasr M, Moussa EA, Kamel EA (2018) Potential impact of host pest fed on Bt corn on the development of Chrysoperla carnea (Neur. http://nonaumorattoire.fr/english.htmnonaumoratoire.free.fr/english.htm: pp. However, in 1995, the Environmental Protection Agency (EPA) in the USA approved the commercial production and distribution of the Bt crops (corn, cotton, potato, and tobacco). Despite the expectation of less Cry1Ab protein digestion and more absorption of Cry1Ab protein into the circulatory system of the GI-impaired rats, there was no evidence of toxicological effects (changes in clinical blood parameters and histologic appearance of organs) in the treated rats. Richter (ed.) 1999). No acute toxicity was shown in mice treated with high doses of Bt toxins, 3280–5000 mg/kg body weight. Currently, the most common Bt crops are corn and cotton (Vaek et al. In general, there are fundamental biological properties of proteins that greatly limit their potential to produce chronic toxic effects when ingested (Hammond et al. (2015) mentioned that such a result could be due to spore components other than Cry proteins. Genetically modified (GM) plants: questions and answers. A second resistant populations of B. fusca to Bt corn was detected in another area in South Africa (Kruger et al. For example, a plant with a desired trait is selected and bred to produce more plants with such a trait. Bt cotton was widely adopted in the USA by farmers in the Western Cotton Belt for the pink bollworm and by farmers in the Mid-south and South-east for primarily tobacco budworm and to a lesser extent for fall armyworm, Spodoptera frugiperda and S. exigua (Stewart 2007). (2006) mentioned that the naturally occurring bacteria in the gut (E.coli and Enterobacter) penetrate to the hemocoel through the disrupted epithelium caused by Bt toxins and multiply causing sepsis of the hemolymph and death of the insect. Arch Environ Contam Toxicol 56:221–228, Sears MK, Hillmich RL, Stanley DE, Oberhouser KS, Pleasants JM (2001) Impact of Bt corn pollen on monarch butterfly populations: a risk assessment. The following types of Bt crops were produced by the researchers: The Bt cotton variety is genetically transformed with the Bt gene to protect the plants from bollworm, a major pest of cotton. Genetically modified crops: A wake-up call? 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. USA grew 72.9 million ha (representing 39% of the world total area), Brazil (27%), Argentina (13%), Canada (6%), India (6%), Paraguay (2%), Pakistan (2%), China (2%), and South Africa (1%). Crops genetically engineered to overexpress EPSP synthase are an example of a plant that will resist herbicides. Genetically-modified (GM) seeds are a significant step forward in the production of agricultural crops. Click ‘Start Quiz’ to begin! Natl. At present, 96% of India’s cotton cultivation area is under Bt cotton crops. Hilbeck et al. The USA and Canada, however, do not have such rules, and almost 75% of their manufactured corn products are made from Bt corn (Anonymous 2012).