Monsantos Roundup Ready is notable example of herbicide resistant

Monsanto's Roundup Ready is notable example of herbicide resistant

This month's management briefing looks at genetically modified food and the debate around the use of GM. Part one presents an overview of the sector, of GM crops, the reasons for their development and the major companies in the biotech sector.

The question of whether the use of genetically modified organisms (GMOs) in food production is safe is one that has exercised producers, retailers, consumers, campaigners and politicians for more than two decades. It is in fact two questions: is GM safe to eat and is it safe for the environment?

Under certain conditions and contingent on testing, the technology is increasingly being used in food production but campaigners would suggest that neither question has yet been comprehensively answered. And the debate goes on.

However, as the GM debate has developed so have global circumstances. The twin global challenges of climate change and food security have heightened the focus on GM. While campaigners raise concerns over the long-term environmental threat and other unpredictable negative consequences of the genetic adaptation of crops, proponents of GM point to the benefits it may offer in meeting the global food security challenge and lowering the climate change impact of food production.

While GM technology is used in or is being developed for a wide range of applications including biofuels and pharmaceuticals, fish, livestock and arboriculture, this report relates principally to its use in food crops and in the production of animal feeds. It looks at the current extent of GM cultivation, examines the food safety issue and the environmental debate over GM, and the role it may play in meeting the food security challenge.

Where are we now?

Hybridisation and plant breeding, whereby a new and genetically distinct strain of a plant or crop with particular properties is developed, has been around for centuries. Thomas Fairchild succeeded in artificially cross-breeding a sweet william and a carnation pink to produce the world’s first artificial hybrid in 1715. As the science of plant breeding has developed, it has had numerous and significant applications in food production.

Latterly developments in genetic science have allowed for the creation of new strains of plants through genetic modification, namely the implanting of a specific gene to give the crop a specific characteristic. Genetic modification can either involve the implanting of a gene from the same species, or 'transgenic' modification adds a gene from another type of organism.

The international GM sector is subject to the Biosafety Protocol within the UN Convention on Biodiversity, agreed in Cartagena in Colombia in 2000. The Cartagena Protocol has so far been ratified by 161 countries, the most recent signatory being Morocco, which signed up in April 2011.

The Protocol lays down some basic rules which governments can adopt to regulate the cultivation and commercialisation of GM foods, crops and seeds. Significantly the Protocol has not been ratified by the US, Argentina and Canada where a significant proportion of the world's GM crops are grown.

The US has the most permissive regulatory approach to GM, and the US is where use of the technology has become most widespread and where foods produced directly from GM crops are most present in the food supply chain. The US, Canada and Argentina combined currently account for around 80% of the total global volume of GM crops.

In the EU, the development of GM is governed by a number of EC directives, while the safety of GM products is assessed by the European Food Safety Authority (EFSA).

While there are some foods in the EU supply chain produced directly from GM crops, such as certain oils, the development has been slower than in the US as a result of the tighter regulatory approach and the reluctance of many retailers to carry GM foods. 

Foods produced directly from GM crops have to be labelled accordingly under EU law. However, meat and dairy products from animals reared using feeds produced from GM crops are widely sold in the EU and there is no EU-mandated requirement for these products to be labelled as such.

GM crops

GM technology is being used in a range of areas including agriculture, aquaculture and arboriculture. For the mainstream food industry and for consumers, arguably the most pertinent GM work has been in staple crops, in particular maize, soy and oilseeds, which are used directly in food production or in animal feed. 

The largest GM-producing countries in 2010 were the US (66.8m hectares), Brazil (25.4m ha), Argentina (22.9m ha), India (9.4m ha), Canada (8.8m ha), China (3.5m ha), Paraguay (2.6m ha), Pakistan (2.4m ha), South Africa (2.2m ha) and Uruguay (1.1m ha).

GM crops can be characterised according to the aims behind the genetic modification and fall broadly into seven categories: herbicide resistance, pest resistance, disease resistance, stress resistance, altering composition, biopharming and bioremediation.

Herbicide resistance

Herbicides cannot differentiate between crops and weeds, so conventional agricultural systems use 'selective' herbicides that will not harm the crops but are not effective in killing all weeds.

However, crops are now being genetically modified to be resistant to non-selective herbicides that can remove all weeds in a single application, meaning less spraying, lower operating costs and lower emissions from farm machinery.    

These transgenic GM crops contain genes that enable them to degrade the active ingredient in a herbicide, rendering it harmless. Herbicide resistant crops also facilitate low or 'no tillage' agricultural practices, which many consider to be more sustainable. 

Critics claim that the use of herbicide resistant crops can lead to increased herbicide use, the development of herbicide resistant weeds and a negative impact on biodiversity. 

Notable examples of herbicide resistant cropping systems for soybean, maize, rapeseed and cotton are Monsanto's Roundup Ready and Bayer's Liberty Link.  

Herbicide tolerant crops represent the largest proportion of the GM crops sector, accounting for 51.3% of the market value in 2009.

Pest resistance

Bacillus thuringiensis, or Bt, is a bacterium that has been used extensively in pest control. The soil bacterium produces a protein that is toxic to various herbivorous insects. The protein, known as Bt toxin, is produced in an inactive, crystalline form and when consumed by insects it is converted to its active, toxic form (delta endotoxin), which in turn destroys the gut of the insect.

Companies have used genetic engineering to take the bacterial genes needed to produce Bt toxins and have introduced them into plants. If plants can be engineered to produce Bt toxin, they can defend themselves against certain insects, eliminating the need for chemical insecticides.  

Critics suggest that in some cases the use of insect resistant crops can harm beneficial insects and other organisms. 

Disease resistance

GM scientists are researching ways of protecting plants from various infections, caused by fungi, bacteria, viruses, nematodes and other pathogens, which can blight crops.

So far, interest has been primarily concentrated on virus resistant transgenic plants, but research to apply biotechnology to confer resistance to fungi, bacteria or nematodes is increasingly being undertaken.

Fungal plant diseases are usually managed with applications of chemical fungicides or heavy metals but conventional breeding has led to the development of some fungus resistant cultivars.

However, genetic engineering enables new ways of managing fungal infections, such as introducing genes from other plants or bacteria-encoding enzymes, which break down the essential components of fungal cell walls. Genes have also been introduced which enhance innate plant defence mechanisms.

Viruses, which cause many significant plant diseases, are usually transmitted by insects and while insecticides are used to control the spread of viruses, success is limited. Conventional breeding has been able to provide some virus resistant or tolerant cultivars but only for a limited range of crops.

Biotechnology is now being used to render crops resistant to viruses, most commonly by introducing a viral gene encoding the virus's 'coat protein'. The plant produces this viral protein before the virus infects the plant. This form of virus resistant genetic modification has been applied commercially to crops such as papaya and squash. 

Stress resistance

GM research is being conducted to make crops better able to cope with site-specific, environmental challenges such as drought, high salt levels or extreme temperatures. For example, tomatoes have been genetically engineered to enable them to grow in salty water. 

One way of engineering drought tolerance is by taking genes from plants that are naturally drought tolerant, such as the resurrection plant (Xerophyta viscosa), native to the dry regions of southern Africa, and introducing them to crops. 

GM sceptics suggest that while stress resistance could be seen as a desirable characteristic to achieve in crops, this has been an area where GM research has so far made least progress.

Altering composition

While GM was originally developed to give crops a particular resistance, for example to pests or herbicides, as the science has developed, more ambitious kinds of modification have been attempted, aimed at substantially altering the composition of the plants. One aim is to provide enhanced product quality or new desirable traits. 

These desired characteristics can have industrial applications, such as potatoes with modified starch content and oilseeds designed to replace petroleum products, but research is also being undertaken to develop transgenic plants to give food crops enhanced health characteristics.

This may involve reducing oil content, vitamin enrichment, increasing the level of protein or amino acids, removing gluten or raising antioxidant levels, and removing or reducing substances such as caffeine.


Biopharming, which is sometimes known as pharming or ‘molecular pharming', uses GM plants to produce pharmaceutical proteins and chemicals, including vaccines, hormones, blood thinning and clotting agents and industrial enzymes. 

In addition to pharmaceutical applications, biopharming has also been used to develop biodegradable 'bioplastics'.


Bioremediation is the use of plants or microorganisms to remove toxic pollutants from the environment. Plants can be modified genetically to enhance their ability to absorb pollutants from the soil. For example, poplars have been engineered to extract heavy metals from soil. 

The biotech industry

While there are many companies involved in GM research and product development, on the agriculture side three companies are particularly prominent, namely Monsanto, Syngenta and DuPont. Other significant players include BASF, Bayer Crop Sciences and Dow Agro Sciences.

The GM industry is also represented by a number of powerful lobbying and advocacy organisations, notably the pan-European organisation, Europabio, and the US-based Biotechnology Industry Organization, or BIO.

Formed in 1993 by the merger of the Association of Biotechnology Companies and the Industrial Biotechnology Association, BIO is the largest biotechnology trade body with 1,100 members. Members are involved in the research and development of healthcare, agricultural, industrial and environmental biotechnology products. BIO's aims are to provide "advocacy, business development and communications services" for those members. 

In addition to small and very large companies, its membership also includes state and regional biotech associations, service providers to the industry and some academic research organisations.

EuropaBio represents the biotech industry in Europe. Its membership includes national biotech associations from countries across Europe as well as biotech companies large and small.

The organisation states that it is "actively actively engaged in dialogue with European institutions and contributes to the creation of a coherent legislation for bioindustries" and "ensures a steady flow of information about biotechnology to the European Parliament, the European Commission and the Council of Ministers".

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