Public Research and Regulation Initiative, PRRI
Global developments such as population growth, loss of arable land, environmental pollution and climate change pose enormous challenges for sustainable agricultural production of food, feed, fibre and fuel. Governments and international organizations invest heavily in public plant biotechnology research to help find solutions to these challenges. This chapter provides a background to modern plant biotechnology, describes areas of ongoing public research and discusses reasons why, despite the massive research efforts over many years, the genetically modified crops made available to farmers today are mainly four crops (soya, maize, cotton and canola) with only two new features or “traits”(herbicide and insect resistance).
Over a period of more than 10,000 years, human society has dramatically changed through the extensive breeding of animals and plants they originally found in nature. Domestication of cattle, sheep, cats, and dogs are well recognized, but people are sometimes unaware that an even more profound domestication has occurred with virtually all plants and trees we grow today as crops, both in developed and developing societies, including maize, wheat, rice, and soybeans. For many thousands of years humans have selected and crossed plants and animals that had the characteristics they wanted, such as higher yield or better taste.
This approach made a major leap forward in the 19th century when the monk Gregor Mendel discovered the rules by which most characteristics were inherited from one generation to the next. Later, scientists discovered that the code for the characteristics of plants, animals and micro-organisms are contained in so-called “genes”, and that genes consist of genetic material, which we call DNA. In the early 20th century, plant breeders discovered that mutations (a small change to the DNA sequence) in plants can not only occur spontaneously, but can also be induced by exposing plant material to radiation or chemicals (mutation breeding). This has become a widely used technique, and many of the crops we consume every day have been obtained with the help of mutations induced by chemicals and ionizing radiation; even though these agents could lead to changes in the plants genetic code that may lead to ‘unintended effects’ i.e. an undesirable new trait.
While cross-breeding and induced mutations are, and will continue to be, extremely important tools for plant breeding, they also have a number of limitations.
1) For some plants cross breeding is extremely difficult or even impossible. Cultivated bananas, for example, are sterile and have no seeds. Banana palms are multiplied asexually, which means that to make new banana palms, parts of an existing palm are used (this is similar to taking cuttings of plants in your garden) and all the resulting bananas are therefore genetically identical or clones of the original palm.
2) Cross breeding only works between plants that are genetically related (sexually compatible). A gene for disease resistance in tomato cannot be crossed into maize, for example, because maize and tomatoes do not cross breed.
3) Cross breeding can take a very long time. For example, it took apple breeders over 50 years to introduce resistance against scab — a major disease of apple trees that requires many sprays with pesticides each season — from a resistant apple tree variety into other varieties.
4) Cross breeding not only brings the desired genes from plant A into plant B, the latter usually being a variety well adapted to the local environment and/or already having other desirable traits, but plant A also brings the tens of thousands of other unwanted or non desirable genes with it. This so-called “linkage drag” (genes carried across with the desired intended gene) forces plant breeders to carry out a long process of “back crossing” with plant B to regain its desirable characteristics (i.e., a plant B plant that contains just the one trait you wanted from plant A).
5) Similarly, while inducing mutations by radiation and chemicals is an extremely useful technique that has had impressive results, it is completely undirected and unpredictable, and often has effects on the other genes of the plants.
To overcome these limitations of cross breeding and induced mutation, in the 1970s scientists developed techniques that made it possible to:
1) identify a specific gene responsible for a trait in an organism,
2) isolate that gene, and
3) bring it into plant cells through a process called “transformation”.
These modern techniques, usually collectively called “genetic engineering”, allows for a precise modification of the genetic material. Genetic engineering is therefore (i) much faster than conventional breeding, (ii) more specific, and (iii) not limited to just the exchanging genes from related plants or species. The reason that in principle any gene from any organism (micro-organism, plant or animal) can be made to function in any other organism is because DNA or the genetic code is a universal code. In fact many genes found in one organism can also be found in another. For example many genes of humans are also found in bacteria, plants, fruit flies, pigs, mice and of course our near relatives, the apes. Many genes in the course of evolution have been transferred from one species to the other, so that we nowadays find, for examples, plants with bacterial genes stably inserted in their DNA.
3. Potential applications
To understand the potential uses of the technique of genetic modification in agriculture, it is important to understand the challenges for food production that the world faces today:
1) The current world population is approximately 7 billion with an unacceptably high proportion of these people undernourished, either in terms of quantity and/or quality of food. The world population is expected to grow to around 9 billion by 2040.
2) The area of land that can be used for agriculture is shrinking because of erosion, pollution, and land being used for other purposes such as buildings and roads.
3) There is increasing shortage of fresh water for drinking and irrigation.
4) Climate change will increase the need for keeping pace with well-adapted crop plants, especially those capable of growing in more arid conditions.
5) Increasing demand for fuels and chemicals from renewable sources as oil reserves become depleted and oil-based commodities more expensive.
6) Eighty per cent of the world’s calorific intake comes from only four crops.
These developments create vital challenges for the world community to:
• produce more crop per hectare
• produce more crop per litre of water
• produce on hitherto non-arable land
• produce more on arid and/or saline land
• enhance the nutritional value of crops
• enhance crop diversity
• reduce dependence on pesticides and fertilizers
• reduce post-harvest losses during storage and transport
• reduce soil erosion.
No single technology can solve these immensely complex challenges by itself. The future of agriculture is not a matter of choosing “either this or that technology” but rather of combining the most suitable approaches of each available technology, tailored to specific needs and situations. It is essential that farmers are given the freedom of choice to select the best crops for both their and the environments needs.
Since 1992, governments and international organisations represented during the United Nations Conference on Environment and Development (UNCED), have repeatedly acknowledged that modern biotechnology — although not a “silver bullet” — can contribute significantly to finding solutions for the above challenges. Agenda 21, the action plan of the UNCED, includes a chapter on “Environmentally Sound Management of Biotechnology” that emphasizes the need to strengthen the endogenous capacities and establish enabling mechanisms for the development and environmentally-sound application of biotechnology.
This has been repeated in the outcome of the World Summit on Sustainable Development in 2002, and the resulting Johannesburg Declaration.
4. Public research in modern plant biotechnology
Over the years governments and international organisations have invested substantially, and will continue to invest in research and development of modern agricultural biotechnology . The types of traits or characteristics in current and planned public plant biotechnology research include:
1. Biotic stress resistance
a. disease resistance:
• fungus resistance in banana (black sigatoka), wheat, yams
• virus resistance in banana, cassava (cassava brown streak virus, cassava mosaic virus), yam (yam mosaic virus), papaya (papaya ringspot virus), groundnut (tobacco streak virus), tomato (tomato yellow leaf curl virus), maize, rice, potato
• bacterial resistance in rice (bacterial late blight), cassava (bacterial blight), banana (bacterial wilt), potato (late blight)
b. pest resistance:
• pests in the field: cowpea (pod borers), maize, cotton, potatoes (nematodes), yams (nematodes), vegetables (sucking insects), chickpea (borers), banana (borers, weevils, nematodes), egg plants (fruit and shoot borer), sweet potatoes (insects)
• storage pests: grains (borers, beetles), potatoes (tuber moths)
2. Abiotic stress tolerance, for example
a. drought tolerance:
• wheat, maize (e.g., the Water Efficient Maize for Africa – WEMA project), rice, sorghum, potato, groundnut, cowpea and watermelon
b. saline tolerance:
• wheat (nitrogen use efficiency), maize, sorghum, tobacco
3. Enhanced nutrition
• rice (provitamin A, vitamin B9, iron, zinc, vitamin E, and high-quality protein), wheat (iron), mustard (provitamin A), maize (protein quality), potatoes (protein quality), cassava (protein, provitamin A, vitamin E, iron and zinc), sorghum (digestibility, protein quality, zinc, iron, and provitamin A), and banana (provitamin A and iron).
4. Other relevant traits
• rice: nitrogen use efficiency
• cassava: reducing existing levels of cyanogenic compounds.
A more extensive list of traits, specific to each of the main EU countries can be found in other chapters published on this website. In these chapters we present the challenges faced in the key EU agricultural crops, the economic impact faced as a result of losses due to the above stresses, and examples of the ongoing biotech work underway aimed at addressing these problems. For some of these challenges, GM offers the best (and sometimes only) approach to solving these problems.
5. Regulatory costs and the current political authorization system are limiting new technology exploitation
Sixteen years (1996) since the first commercial planting of a GM crop, today the GM crop market is still limited to mainly four GM crops with only two traits despite the massive research efforts and successes with other crops/ traits.
The genetically modified crops that are currently available to farmers are primarily soy beans, maize, cotton and rapeseed with improved insect resistance and/or herbicide tolerance. In 2011, these crops were grown on 160 million hectares by over 16.7 million small and large farmers in 29 developed and developing countries (James, 2011).
While the performance of these GM crops varies from case to case, depending on the specific farming systems in which they are released, the aggregated impact to date on farm-level incomes is substantial (PG Economics, 2011). More importantly, the environmental benefits include a decrease of hundreds of millions of kilograms of pesticides as well as significant reduction of soil erosion and fossil fuel use due to low-till farming practices made possible by herbicide tolerant crops. In addition, the health and livelihoods of farmers, particularly in developing countries, have been improved through reduced exposure to toxic chemicals and the adoption of more environmentally-benign chemicals.
A study by the Joint Research Centre of the European Commission concluded, after thorough research of the published data, that:
“….The picture emerging is that adoption of GM crops has taken place at a rapid rate and driven by a number of reasons including on-farm and off-farm benefits. On-farm benefits are derived from reducing production costs (weed control costs for HT crops and pest control costs for Bt crops). For some crops there are also yield increases (particularly in the case of Bt cotton), affected in some regions by the fact that GM traits have not yet been introduced in all local varieties. The net economic benefits for farmers are variable in regional terms….”
(Gomez-Barbero and Rodriguez-Cerezo, 2006)
“….Ex post analyses also show that adoption of dominant GM crops and on-farm economic gains have benefited both small and large farmers. Small farmers have shown no difficulty in adopting the technology and adoption rates are not related to farm size. Moreover, detailed analyses (for example of Bt cotton in China) show that increases in gross margin are comparatively larger for smaller and lower income farmers than for larger and higher income farmers….”
(Gomez-Barbero and Rodriguez-Cerezo, 2006)
“…Ex post analyses provide data on the effects of GM crop adoption on the use of agricultural inputs. Bt cotton adoption has resulted in a significant decrease in the use of insecticides in all cases studied (25% of all insecticide used in agriculture world wide is for cotton cultivation). Bt maize adoption has induced only a little decrease in insecticide use since the pests Bt maize is designed to resist were not usually controlled by insecticide applications. The adoption of HT soybean has resulted in the displacement of several herbicides by one single product that is considered to be less toxic than the herbicides it replaces. Use of this herbicide has increased. HT soybean adoption has been associated with reduced fuel consumption per hectare and with the adoption of reduced soil tillage practices….”
(Gomez-Barbero and Rodriguez-Cerezo, 2006)
However, despite decades of often successful research efforts with many crop plants, particularly in the public research sector, very few GM crops have actually been made available to farmers. One of the biggest hurdles to developing GM crop plants is that complying with regulations has become unnecessarily difficult, lengthy and costly, and therefore inhibits public research institutions with small budgets. Traits or crops that cannot create enough return on investment to recoup the significant regulatory investments, make it almost impossible for public projects to go ahead unless a project is recognised as a national or international priority and receives additional funding for regulatory purposes. This poses a problem for the whole public research funding community; as projected regulatory costs far exceed the budgets for R&D as such.
Since the introduction of modern biotechnology, national and international biosafety regulations have been established in order to allow policymakers to make informed decisions based on an evaluation of potential benefits and potential risks. However, the general feeling of many researchers is that regulatory decisions for field trials or placing on the market are often either unnecessarily delayed, or denied without balanced, science based assessment. There are believed to be three main reasons why decisions are delayed:
1) Decision makers often find it difficult to come to decisions under the current public or political pressure and therefore delay decisions. This seems to be the case, for example, in the European Union where certain dossiers remain undecided for years. For instance, herbicide-tolerant sugarbeet has been grown successfully in countries like Canada and the USA since 2008, and yet a similar application in the EU has been in the system for 4 years awaiting approval. Indeed the last (and only 2nd) GM crop to gain regulatory approval in the EU for cultivation was a GM potato with altered starch properties (Amflora) that took over 13 years in the regulatory review system.
2) Many researchers believe that there are too many cases where authorisations are denied without adequate assessment. The impression is that the key factor in this is an unbalanced evaluation of environmental risks and environmental benefits, whereby the “risk” factor receives disproportionate weight despite scientific evidence and advice, and that the “benefit” factor is under-valued or ignored.
3) In some cases there is uncertainty about the legal framework. This is particularly the case with transboundary movement of GMOs from one country for field testing in another country that does not yet have biosafety regulations in place. For these cases the Cartagena Protocol on Biosafety has been established. One of the main purposes of the Protocol is to allow decision makers in countries that do not yet have biosafety regulations in place to make informed decisions on the import of genetically engineered organisms for field testing, based on a procedure called AIA (Advanced Informed Agreement).
Gomez-Barbero, M. and E. Rodriguez-Cerezo. 2006. Economic Impact of dominant GM Crops Worldwide: A Review. Seville, Spain: European Commission, DG JRC – Institute for Prospective Technological Studies.
James, C. 2011. Global Status of Commercialized Biotech/GM Crops: 2011. ISAAA Brief 43. Ithaca, NY: International Service for the Acquisition of Agri-biotech Applications.
PG Economics. 2011. Focus on Yields. Biotech crops: evidence of global outcomes and impacts 1996 – 2009. Dorchester, U.K.: PG Economics.