The Bt brinjal is a transgenic brinjal created by inserting a crystal protein gene (Cry1Ac) from the soil bacterium Bacillus thuringiensis into the genome of various brinjal cultivars. These Brinjal plantare foundto be resistance against lepidopteran insects like the Brinjal Fruit and Shoot Borer Leucinodes orbonalis and Fruit Borer Helicoverpa armigera.
Importance of Brinjal in INDIA :
Brinjal is a low calories and fats containing vegetable and contains mostly water, some protein, fibre and carbohydrates. It is also an excellent source of minerals and vitamins and is rich in water soluble sugars and amide proteins among other nutrients. The brinjal is a popular component of the Indian diet across the country. It is an important ingredient in Ayurvedic medicine and is of special value in the treatment of diabetes and liver problems.
Need to produce Bt brinjal:
Brinjal is an important food crop for India, and the potential commercialization of a genetically modified variety provide support and criticism. Brinjal is a major food crop in india but its yield is found to be low as compared to its need because the fruit and shoot borer infestation found to be a major constraint to yield.Field trials conducted on research-managed farms carried out by Mayhco and the Indian Council of Agricultural Research suggested a 42% pesticide reduction and a doubling of the yield was possible by producing Bt Brinjal.
Production of Bt Brinjal by Genetic modification:
Bt brinjal is produced by the technique of genetic engineering in which transfer of a selected fragment of DNA capable of performing new functions from one organism to another takes place. Genetic Modification (GM), Genetic Manipulation and Genetic Engineering (GE) all refer to the same thing. It is also known as recombinant DNA technology.
Bt Brinjal is the first Genetically Modified food crop in India that has reached the approval stage for commercialization. Bt Brinjal has been developed by inserting a gene cry1Ac from a soil bacterium called Bacillus thuringiensis through an Agrobacterium-mediated gene transfer. It is a genetically modified brinjal developed by the Maharashtra Hybrid Seed Company Ltd. (Mahyco), a leading Indian seed company. Bt brinjal contains three foreign genes which have been inserted namely:
1. The cry1Ac gene which encodes an insecticidal protein Cry1Ac, is derived from common soil bacterium Bacillus thuringiensis (Bt) subsp. kurstaki to produce the insecticidal protein. The cry1Ac gene is driven by a viral promoter, the cauliflower mosaic virus (CaMV) 35S promoter.
2. The nptII gene for an antibiotic resistance marker, neomycin phosphotransferase-II.
3. The aad gene for another marker 3” (9) O-aminoglycoside adenyl transferase.
Work of cry protein to give resistence:
When fruit and shoot borer larvae feed on Bt brinjal plants, they ingest the Bt protein Cry1Ac along with plant tissue. In the insect gut, which is alkaline with a pH >9.5, the protein is solubilized and activated by gut proteases. The Bt protein binds to specific receptor proteins present in the insect membrane, resulting in pore formation in the membranes. This leads to disruption of digestive processes, paralysis, and subsequent death of the fruit and shoot borer larvae. The cry1Ac gene along with two other supporting genes namely nptII and aad genes are put together in such a way that they work in tandem to produce insecticidal protein that is toxic to the targeted insect, in this case the fruit and shoot borer.
Bt Brinjal production History in India
In year 2000-2002 Transformation and greenhouse breeding to study growth, development and efficacy of Bt brinjal had started in India.and many field trials hasd been started to know germination, aggressiveness and weediness,biochemical, toxicity and allergenicity in 2002-2004. Then to start large scale field trials for the production of Bt brinjal Mahyco submits bio-safety data to Genetic Engineering Approval Committee (GEAC) in 2006 and it is approved byGEAC in 2007.As per GEAC direction, Indian Institute of Vegetable Research [IIVR] takes up the responsibility of large scale trails of Mahyco’s Bt Brinjal trials at 10 research institutions across the country in 2007 and 11 in 2008 . In 2009 Oct.15th Responding to strong views expressed both for and against the release of the Bt Brinjal, the
Minister of State for Environment and Forests (I/C) (to whom the GEAC reports) announces a nationwide consultation in January and February of 2010 pending a final decision on this issue.
Controversy of Bt brinjal in India:
Bt Brinjal has generated much debate in India. It has many advantages as the promoters say that Bt Brinjal will be beneficial to small farmers because it is insect resistant, increases yields, is more cost-effective and will have minimal environmental impact. But their are many disadvantages related to the production and use of Bt brinjal Bt Brinjal relate to its possible adverse impact on human health and bio-safety, livelihoods and biodiversity. Importantly, the spread of the GE Bt gene could result in the brinjal becoming an aggressive and problematic weed, the Greenpeace report suggests, while impressing upon the governments the need to employ the precautionary principle and not permit any authorisation of the outdoor cultivation of GE Bt brinjal, including field trials. The cultivation of GE Bt brinjal is proposed in some countries across Asia, including India, where there is currently a moratorium on commercialisation, and the Philippines, where field trials are going on.
When Bt Brinjal was sought to be introduced in the market a few years ago, it led to a controversy. However, on February 9, 2010, the ministry of environment and forests imposed a moratorium on Bt Brinjal. In the absence of scientific consensus and opposition from state governments and others, the ministry decided to impose a moratorium on the commercialisation of Bt Brinjal until all concerns expressed by the public, NGOs, scientists and the state government were addressed adequately. Clearance of Bt Brinjal as a commercial crop by genetic engineering approval committee(GEAC) in October 2009 and then its ban by government of india in february 2010, and it become a point of debate whether bt Brinjal should be commercialize or not. However the Minister of State (I/C) for Environment and Forests, responding to strong views raised both for and against the introduction of the Bt Brinjal, has called for public consultations across the country before taking a final decision on this issue.