Brazilian virus-resistant beans

Written by Lúcia de Souza

A homemade, high potential benefit-driven development from the public sector

Beans are an important food item, mostly in the developing world. Unfortunately, the golden mosaic virus infection is a serious constraint causing severe grain losses in Brazil and South America. The National Technical Commission on Biosafety (CTNBio) approved the genetically modified golden mosaic virus-resistant beans developed by the Brazilian public Agricultural Research Corporation (Embrapa) linked to the Ministry of Agriculture, Livestock and Supply. This work is an example of a public-sector effort to develop useful traits, such as resistance to a devastating disease, in an “orphan crop” cultivated by poor farmers throughout Latin America. It is a milestone as it is the first fully “publicly funded homemade” recombinant biotechnology crop improvement strategy that has reached this stage in a developing country.

Why are the virus-resistant beans so important?


Beans are highly nutritious and one of the most important legume consumed by over 500 million people in Latin America and Africa. In Brazil it is regularly an indispensable item of the everyday diet, often combined with rice and eaten by all social classes in all parts of the nation. They are found in a great variety of types with different sizes, colors and tastes consumed throughout the country. Perhaps, the most typical Brazilian dish is the ‘feijoada”, a black beans stew. The local consumption is around 16 kg per person every year. Given its high protein (15 to 33%) content besides B vitamins and minerals as iron, calcium and phosphorus, beans provide a high nutritional value meal. Moreover, beans are the major source of protein for the economically disadvantaged.
Currently Brazil is the largest producer, responsible for approximately 20% of the global production. It is estimated that the domestic production should reach 3.8 million tons in the 2010/2011 period. This is mostly an achievement of small farmers (less than 100 hectares) responsible for approximately 70% of the country’s production. In spite of this high domestic production, Brazil does not produce enough to meet its own needs.
Golden Mosaic Virus symptoms

The major threat to the farmer’s plants, causing losses of up to a 100%, is the golden mosaic virus, which is transmitted by the whitefly Bemisia tabaci in a persistent and circulative manner. That means that once the insect gets the virus it will transmit the disease to the crop its whole life. Only one to three whiteflies per plant in a field are enough to infect all plants. With the spread of the disease throughout Latin America, hundreds of thousands of hectares were either abandoned or could not be cultivated without heavy use of insecticides with limited efficacy. This kind of control has resulted in the development of insecticide resistance, adverse environmental effects, and health hazards to field workers throughout the region. In Brazil alone, annual losses vary between 90,000 and 280,000 tons. That would be enough to feed up to 18 Million adults in the country. There are 180 to 200 thousand hectares that are not suitable for cultivation.

The long way to develop the virus-resistant beans.

The search for bean varieties resistant to the golden mosaic virus (BGMV) begun in the 70’s. It was hoped to obtain plants immune to this disease through conventional breeding methods. Thousands of lines were evaluated for natural resistance or immunity to the disease, but the extensive screening of common bean germplasm found no genotypes with satisfactory level of resistance to BGMV. With the advent of genetic engineering new strategies have been employed in addition to conventional breeding. Finally a successful strategy was found. The strategy was the use of RNA interference (RNAi) that mimics natural silencing mechanisms. Infected plants naturally produce silencing mechanisms that interfere with the virus in the bean cells, unfortunately not effective enough against this disease. The new “vaccinated” variety produces small fragments of RNA that will activate its defense mechanism to silence the viral rep gene, which leads to the synthesis of an essential protein for the replication of the virus. Consequently, without this protein, replication of the virus is compromised and the plants become resistant to the disease.

The virus-resistant GE bean plants are on the top. The original susceptible bean is on the bottom. Look at the difference a single transgene makes!

Safety and the way from research to seed market

Safety precautions for modern agricultural biotechnologies start at the very beginning of the research at the lab, and continue through the different phases of the development. Only when detailed scientific assessments determine it to be innocuous is the new development considered for commercial use. Prior to the submission for the commercial release, a comparison between the virus-resistant beans and its parental conventional/non-modified variety in all the ecosystems where the beans are cultivated in Brazil had been conducted by a consortium of 10 research centers over several years. Results showed that the transgenic beans do not differ in the environmental impact compared to its non-engineered parent beans. Additionally, the transgenic beans offer the advantage of reducing insecticides that have being used to kill the whiteflies that transmit the golden mosaic virus during the past decades. The new virus resistant beans are also considered as safe for consumption as the currently cultivated beans. On that ground, CTNBio, the multidisciplinary commission responsible for making science-based, technical assessments for the safety of genetically engineered products approved the beans for commercial release.
Approvals by CTNBio may be followed by an examination from the National Biosafety Council (CNBS) on the socio-economic convenience and opportunities of national interest.
There are in any case, further steps to be pursued on the way to market the seeds, such as the incorporation of the trait into cultivars suited to the different local conditions, the registration of the variety and production of the seeds. The following step is the law inspired by the UPOV Convention (International Union for the Protection of New Varieties of Plants), legislation that came with the intend of protecting the rights of developers of plant varieties, no matter if obtained through conventional breeding or modern biotechnology, while encouraging investment in research and development. According to the legislation, any plant variety with a minimum of clearly new distinguishable characteristics goes through a process to be registered.  After the approval of registration the new variety enters the fields of seed production. Farmers will probably have to wait another 2 to 3 years to see the virus-resistant beans.

For more information

Do you want to know more about the virus resistant beans? See for example: Kenny Bonfim et al; RNAi-Mediated Resistance to Bean golden mosaic virus in Genetically Engineered Common Bean (Phaseolus vulgaris); MPMI Vol. 20, No. 6, 2007 (Link) and Aragão and Faria, First transgenic geminivirus-resistant plant in the field, Nature Biotechnology Vol. 27, 1086-1088, 2009 . (link)

Do you want to know more about the Brazilian legislation on biosafety? See: CTNBio webpage ( )

I am thankful to Dr. Francisco Aragão for reviewing the text.
Editor’s Note: You will find these fantastic virus-resistant beans added to the rotating header images on our blog!

Written by Guest Expert

Lúcia de Souza has a PhD in plant biochemistry from the University of Basle in Switzerland. She has extensive experience in teaching and is actively involved in biosafety, public research, and regulation initiatives. Lúcia is an ISAAA (International Service for the Acquisition of Agri-biotech Applications) associate.


  1. Good on the Brazilians!
    Maybe this can pave the way for Golden Rice and virus-resistant Sweet-Potatoes, and encourage the development of other new varieties to reduce suffering, disease and death among smallholders and subsistance farmers elsewhere.
    I look forward to Brazil becoming an exporter of beans; the article is correct: they are, as we all know, nutritious and delicious, as well as a valuable tool for sustainable agriculture.

  2. Since golden mosaic virus is a plague throughout South America, we should start some betting pools.
    1. How soon will seeds for this GM bean be smuggled into another country in South America, without a permit?
    2. Which country will be the first to detect the illegal beans?
    3. Which NGO will be the first to declare that farmers are ‘being forced’ to grow the GM beans?

  3. Thanks for this Lúcia. I had seen the press release but very much wanted the additional details you’ve provided.
    This is one of those cases we were waiting for–a public/government project that helps all sorts of farmers and benefits consumers and the economy.
    Please keep us posted on the progress.

  4. Eric,
    I’d add a bet as to who will first raise a fear of “superweeds” due to (extrogression?) wild beans acquiring the virus resistance. Of course, we never hear of wild beans contributing their higher toxicity (lectins and saponins, I believe) into domesticated varieties.

  5. Heartly congratulations, Lucia.
    A long awaited further example of a public good GMO from the public sector.
    I wish this Brazilian Bean a bright future!
    Ingo Potrykus

  6. Earlier this year, someone who did some research with beans was talking about them & their importance in developing countries, and I asked if there was any chance of a transgenic bean being used. He said he didn’t think it was too likely, since it was a ‘poor man’s crop’ and going through everything to get approval would be too much. I’m glad he was turned out to be wrong on that one. Good for Brazil. Now, to await watching the bean succeed, and I too have some morbid curiosity as to how various groups (everyone knows which ones) are going to spin this.
    Not to be negative by bringing this up in the face or warm wishes, but one thing I noticed that might be of interest is there’s someone claiming the beans failed 20 out of the 22 tests. Does anyone happen to know the meaning of that statement? The guy who said it is from the Brazilian National Council for Food Security and Nutrition (otherwise I’d be more inclined to dismiss it as the obligatory nay-saying we’ve all come to expect). He later goes on to say that the bean has not been tested for all Brazil’s ecosystems (I can’t tell if he is playing that ‘only GE crops need to be able to adapt everywhere’ card or saying something else) and then he cites the precautionary principle, which isn’t what I’d call a good sign. Then he says that policies, not improvements in yields, are what is needed (can’t get through one of these things without a false dichotomy to round it off). Anyway, regardless of the veracity or lack thereof of that claim, I don’t expect this will be the last we hear of it so it might be worth looking into.

  7. This argument that not all of Brazil’s different climates and ecosystems were taken into account in the evaluation process was brought by the usual opponents of the technology before the approval of the virus resistant beans. The point is that Beans don’t grow everywhere and are not cultivated everywhere in the country. Therefore, testing the beans everywhere seems an extra waste of resources that brings no useful data. They were tested on the representative ecosystems that they are cultivated in Brazil. After the criticism, the conclusions were once more reviewed and the majority of the CTNBio members obviously considered irrelevant to test in all climates, etc. of the country therefore kept it’s original statement and approved it without restrictions (e.g. GM cotton is allowed in certain areas of the country but not everywhere because of landraces).
    The assessment is on a detailed case by case base, the text doesn’t explain which tests they are talking about…so I can’t say anything. But one thing is for sure, if any GM crop fails 20 of 22 tests, it surely would be not approved.

  8. “This argument that not all of Brazil’s different climates and ecosystems were taken into account in the evaluation process…”
    This problem was encountered not long ago with smuggling of GM soybean seed from Argentina into Brazil. A fair quantity of smuggled GM varieties were not well-bred for some regions of Brazil (a truly huge country), and there were crop failures as a result. And, of course, activist claims of ‘GMO failure’.
    Once legalized, herbicide tolerant soy cultivars with genetic backgrounds suitable for various regions emerged, and the rest is history.

  9. Ingo and all of you, I would like to thank all for the warm wishes and the congratulations (merit is actually more deserved to other people than me, I can’t even name them all, so I forwarded only to those I had the contact…).
    It is a pity that all too often there is a failure to identify the most relevant issues, that fear is placed disproportionate to actual risks/dangers. I mean minor dangers even sometimes only hypothetical are blown out of proportion and more serious and even with extensive data to strongly show its importance are not given the priority it deserves or go largely unnoticed. These unbalanced or exaggerated fears in comparison to real issues often lead to unnecessary measures and legislation and weird consequences. Among them the paradoxical use of resources that would be more beneficial to environment and society if placed on more pressing and real problems than exaggerated testing hypothetical risks even when its known that existing and in place alternatives are no better. Besides, as pointed out several times, it creates the huge economical barrier that public research developments face to bring its goods to benefit society when it is developed by a technolgy that suffers from “prejudice” such as modern biotechnology for agriculture.
    I also wish the golden rice a bright future. It’s so sad that so many children lose sight and even die due to vitamin A deficiency. It’d be much more gratifing to see or know that these kids are cheerfully playing and smiling thanks to more options to help fighting this problem including enriched rice or any other and absolutely with no unnecessary delay.

  10. It is interesting to remember that already in 1998, the RR soybeans were considered safe for human, animal and environemnetal health (commercial release) by CTNBio.Those engaged in the Campaign for a GMO-free Brazil started a long legal dispute against the decision. Different positions and interests spawned a complex tangle of regulations whose implementation, in turn, caused bureaucracy to get out of hand. It harmed Brazil’s scientific development. Farmers felt difficult to compete with prices offered by the major soybean producers (USA and Argentina) and adopters of the GM technology in the international market wihout a premium price for its non-trangenic soy. Those producers on the neighboring regions started to smuggle seeds from Argentina. It indeed reduced the costs by reducing the total use of herbicides and facilitated the cultivation because of no-till need for those on the south of the country, and as a result adoption was high even when it was illegal before the end of the legal dispute.
    After an intense debate about the technical, scientific, economic, legal, political, and ethical aspects of the matter, a new version of the Biosafety Act was formulated in 2005. It was inspired by utmost caution and a stringent evaluation but it is under the new legal framework and clear policy that intend to foster scientific development in priority areas (agriculture, health, biofuels….) that the situation about modern biotechnology has changed in Brazil.

  11. I know this is an old post, but I wanted to add something I saw today on beans from Brazil:

    Finally, from Brazil’s Embrapa come 514 samples of what is simply known as “the common bean” but which plays an uncommonly prominent role in Brazilian cooking and culture. In much of Brazil, feijão preto, or black beans, are eaten with virtually every meal and are the crucial ingredient in Feijoada, a stew of beans and pork many consider to be Brazil’s national dish.
    I’m glad to see multiple strategies to keep this important food available.

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