BIOSAFETY AND BIOREGULATORY MECHANISMS FOR TRANSGENIC CROPS

India ranks second in world after China in the production of vegetables and fruits worldwide and these crops play an important role in human diets because they provide vitamins, minerals, dietary fiber, and phytochemicals. Flower market in India growing at increasing rate and export potential of such crops are very high in global market. Horticulture production suffers from many abiotic and biotic stresses caused by pathogens, pests, and weeds and requires high amounts of plant protection products per hectare. Transgenic crops (genetically modified/GM), crops enable breeders to bring favorable genes, often previously inaccessible, into already elite cultivars, improving their value considerably and offer unique opportunities for controlling insects and other pathogens. This novel “molecular farming” offers enormous possibilities, but will require stringent regulations and control mechanisms to avoid new, potentially serious risks human health, though possible contamination of the food supply. Transgenic plant breeding therefore provides genetically enhanced seed embedded technology that contributes to integrated pest management in horticulture by reducing pesticide sprays as well as improving food safety by minimizing pesticide residues. Furthermore, herbicide-tolerant transgenic crops can help reducing plough in fields, thereby saving fuel because of less tractor use, which also protects the structure of the soil by reducing its erosion. Transgenic horticulture crops could make important contributions to sustainable horticulture production.

Advances in Biochemical Engineering/Biotechnology, 2008

Transgenesis is an important adjunct to classical plant breeding, in that it allows the targeted manipulation of specific characters using genes from a range of sources. The current status of crop transformation is reviewed, including methods of gene transfer, the selection of transformed plants and control of transgene expression. The application of genetic modification technology to specific traits is then discussed, including input traits relating to crop production (herbicide tolerance and resistance to insects, pathogens and abiotic stresses) and output traits relating to the composition and quality of the harvested organs. The latter include improving the nutritional quality for consumers as well as the improvement of functional properties for food processing.

Nature Biotechnology, 2005

The costs of meeting regulatory requirements and market restrictions guided by regulatory criteria are substantial impediments to the commercialization of transgenic crops. Although a cautious approach may have been prudent initially, we argue that some regulatory requirements can now be modified to reduce costs and uncertainty without compromising safety. Long-accepted plant breeding methods for incorporating new diversity into crop varieties, experience from two decades of research on and commercialization of transgenic crops, and expanding knowledge of plant genome structure and dynamics all indicate that if a gene or trait is safe, the genetic engineering process itself presents little potential for unexpected consequences that would not be identified or eliminated in the variety development process before commercialization. We propose that as in conventional breeding, regulatory emphasis should be on phenotypic rather than genomic characteristics once a gene or trait has been shown to be safe.

Biotechnology Annual Review, 2001

Present increasing trend of population is alarming for food shortage. It was estimated that by the year of 2050 the population rate may increase up to 9 billion. Rapid increase of human population together with global climate variability resulted in increased demand of plant based food and energy sources. Conventional breeding is still limited due to genetic restrictions (high heterozygosity and polyploidy), long juvenile periods, selfincompatibility, resources restricted to parental genome and exposed to sexual combination. Thus, there is an urgent need for the biotechnology-assisted crop improvement, which ultimately aimed to obtain novel plant traits. Plant genetic engineering has opened new avenues to modify crops, and provided new solutions to solve specific needs. Therefore, this paper reviews the recent trends in the field of transgenic in fruit crops.

In Vitro Cellular & Developmental Biology - Plant, 2002

Recombinant DNA technology has great potential to enhance and extend the advantages of conventional plant breeding, and increase the production and productivity of crops to meet the increasing demand for food and food products in the future. Judicious application of this technology provides opportunities for alleviating some of the major constraints to crop productivity under subsistence farming conditions in the developing countries. Considerable progress has been made in developing strategies for the production and deployment of transgenic crops. However, biosafety concerns have been raised regarding the deployment and release of genetically engineered plants. This debate has divided the farming and consumer communities over acceptability of genetically modified foods. There is a need for a thorough investigation regarding the fate of transgenic plants in the environment, and their interaction with wild relatives and non-target organisms. The production and release of transgenic plants should be based on experience and sound scientific reasoning. The regulatory requirements for deployment of transgenic crops should be streamlined and harmonized, in order to achieve sustainable food production, poverty reduction, and environmental protection in resource-poor countries in the semi-arid tropics.

Journal of Experimental Botany, 2000

in the modification of agronomic performance. Data will be provided from a range of sources including details of Transgenic crops are now grown commercially on sevapplications for the field testing of experimental material, eral million hectares, principally in North America. To and from recent patent applications which make claims date, the predominant crops are maize (corn), soybean, to novel approaches to this problem. cotton, and potatoes. In addition, there have been field Throughout this review emphasis will be given to recent trials of transgenics from at least 52 species including publications, which should be consulted if additional all the major field crops, vegetables, and several herbinformation is required. aceous and woody species. This review summarizes recent data relating to such trials, particularly in terms of the trends away from simple, single gene traits Present status of transgenic crops such as herbicide and insect resistance towards more complex agronomic traits such as growth rate and The first transgenic plant product marketed commercially increased photosynthetic efficiency. Much of the was the well-known 'Flavr Savr' tomato which had been recent information is derived from inspection of patent modified to contain reduced levels of the cell wall databases, a useful source of information on commersoftening enzyme polygalacturonase. Tomato purée with cial priorities. The review also discusses the time scale a similar type of modification has been on the market in for the introduction of these transgenes into breedthe UK since February 1996. Since that time, however, ing populations and their eventual release as new there has been a massive expansion in the growth of varieties. transgenic field crops, particularly maize, soybean, oilseed rape, and cotton, such that in North America transgenic Key words: Genetic modification, field trials, photosynvarieties now represent the majority of the acreage of thesis, chlorophyll, stress responses. these crops. For example, it is now estimated that 70% of the Canadian oilseed rape crop in 1999 will be genetically modified. Most of the varieties grown to date have I would like to thank the Biotechnology and Biological Sciences Research Council (BBSRC) and ZENECA plc for financial support and other assistance during the preparation of this Public perception and acceptance review. Recent attention in the media and elsewhere has shown that many sections of the general public in the UK are uneasy about the safety of genetically modified crops and References food derived from such crops (see above) (Dunwell, 1998b). This issue is forcing a political reappraisal of the

Biological Resource Management Connecting Science and Policy, 2000

2009

Applications of herbicides, pesticides, and fertilizers have greatly increased crop yields in the past. More recently, however, crop yields are barely keeping up with world growth, hence the need for new approaches. Agricultural biotechnology may likely play a key role in the race to feed the world’s expanding population with fewer inputs and on less and less available land. Genetic engineering of plants represents the next stage of evolution in our continuing efforts to improve plants used for the production of food and animal feed. Agricultural biotechnology is a powerful technique offering great potential for agricultural sustainability and safe production of foods with increased nutritive value, improved flavour, prolonged freshness, and even disease-fighting properties, but it is not without controversy. The potential for the transgenic crops to alleviate human hunger, and the controversies which are invariably based on visions of the new technology from widely different ethica...

Nature Biotechnology, 2005

To the editor: In presenting their justifications for reducing the regulatory burden on transgenic food crops (Nat. Biotechnol. 23, 439-444, 2005), we feel that Strauss and colleagues significantly misrepresent the implications and rationale of our report Genome Scrambling-Myth or Reality? Transformation-Induced Mutations in Transgenic Crop Plants 1. Unlike their characterization of our work, we did not specifically "argue for rejection if even a single base pair is changed." In full, our relevant recommendations were that "transgenic lines containing genomic alterations at the site of transgene insertions be rejected" and that "the insertion of superfluous DNA be considered unacceptable." Leaving aside the fact that a single base pair change may result in serious phenotypic consequences, these recommendations are best viewed in context. As documented in the report, thorough analysis reveals that all particle bombardment transgene insertion events include extensive rearrangements or loss of host DNA as well as insertion of superfluous DNA. Furthermore, a large fraction of even apparently simple Agrobacterium tumefaciens-mediated transgene insertion events also result in large-scale host DNA rearrangement or deletion and superfluous DNA insertion 2. For example, loss of 76 kbp of host DNA 3 and duplication/ translocation of up to 40 kbp of host DNA have been reported at T-DNA insertion sites 4. Widespread use of transgenic crops carrying insertion-site mutations of this magnitude will, in our opinion, lead sooner or later to harmful consequences. Nevertheless, detailed inspection has shown that mutations such as these would almost certainly pass unnoticed through both the molecular and phenotypic characterization stages of the regulatory systems of both the European Union and the United States 5-8. We do agree with Strauss and colleagues that analysis of the phenotype is the one true measure of safety. However, rigorous assessment only at the phenotypic level is time consuming, expensive and, more importantly, of unproven effectiveness 9. In this context, our recommendations for the detection and elimination of transformation-induced mutations from commercial crop plants are conceived as a straightforward and effective way to reduce the probability of unexpected deleterious phenotypes arising in transgenic crop plants and of protecting consumers and others from an unnecessary risk.