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Fields of gold

Will drought-proof maize and biofortified bananas help combat world hunger or create new problems?

Lezette Engelbrecht
By Lezette Engelbrecht, ITWeb online features editor
Johannesburg, 31 Oct 2011

Rachel, a farmer in rural Uganda, sits on the floor sorting through the pile of sweet potatoes she has harvested from the plot outside. She hacks away at an earthy lump with a machete until it's reduced to the size of an egg, placing it carefully on a separate pile and starting on the next one. So it continues, until the initial heap of root vegetables is whittled away to several large marbles that will make up the family's dinner.

This is necessary because Rachel's family isn't the first to get a taste of the sweet potatoes - that privilege belongs to the weevils infesting the crop, which means any potatoes gathered are riddled with tiny grooves where the insects have bored their way through.

It's a fate shared by millions of others in Uganda, where about 44% of farmers grow the staple crop, and the average person consumes 82kg of sweet potatoes a year.

In a country where agriculture directly or indirectly provides a livelihood to almost 90% of the population, where almost 10 million don't have enough food to meet their daily needs, and a large number suffer from nutritional deficiencies, agricultural biotechnology could play a life-changing role.

According to the UN's Food and Agriculture Organisation (FAO), biotechnology's chief benefit is the ability to create resilient, drought-tolerant crops, which could keep farming communities afloat during hard times.

Which is why the Bill & Melinda Gates Foundation (B&MGF) is investing nearly $20 million into the development of tougher, more nutritious crops through its Grand Challenges in Global Health initiative.

This forms part of a broader effort to boost the levels of vitamins and minerals in crops that make up the bulk of developing world diets. The foundation's Agricultural Development initiative has so far contributed approximately $1.7 billion to various programmes aimed at helping small farmers improve yields, combat hunger and secure sustainable incomes.

Gene in a bottle

Speaking at the Agricultural Biotechnology International Conference, in Sandton, last month, University of Cape Town professor Jennifer Thomson noted that the world will need to feed around nine billion people in 2050, and 10 billion in 2100.

“Conventional crop improvements alone will not double crop production by 2050. Genetically modified and biotechnology crops are not a panacea, but they are essential.”

She added that a successful strategy must use multiple approaches - making the best of old and new methods - to contribute to food security in the face of climate change.

Biotech crops can bring great improvements in production and farm incomes, with gains of $65 billion between 1996 and 2009, said Thompson. Boosting the quality and quantity of crops grown is essential in many developing countries, where yields are low due to pests and weather.

Also speaking at the conference, Lawrence Kent, senior programme officer focusing on agricultural research and technology transfer at the B&MGF, said the foundation supports a range of crop breeding techniques, with genetic modification being only one.

“While it constitutes a small portion of the foundation's investments in agriculture and nutrition (about 6%) it is one that we believe has promise.”

When it comes to subsistence farmers like Rachel, traditional pest control is often not an option, and developing a weevil-resistant sweet potato using conventional breeding methods has not been hugely successful. While they're smaller than a fingernail, these tiny beetles can destroy 60% to 100% of sweet potato crops during intense and prolonged droughts. With climate change likely to create even hotter and drier conditions in sub-Saharan Africa, the impact of weevils may become unbearable.

The world will need to feed around nine billion people in 2050, and 10 billion in 2100.

Prof Jennifer Thomson, UCT

“So why not create a weevil-resistant sweet potato using biotechnology?” said Kent. This involves implanting crops with a bacterium known as Bt, which produces a crystal protein lethal to insects. Bt sweet potato, once regulated and approved, can make big difference to smallholder farmers like those in Uganda, he said.

One initiative working in this area is the Sweet Potato Action for Security and Health in Africa project, a five-year initiative aimed at improving food security and livelihoods on the continent.

With the B&MGF providing major funding, one of the programme components focuses specifically on developing weevil-resistant sweet potato varieties - something which would see Rachel spending a lot less time hacking her harvest to pieces.

Superfoods

While new techniques may rid farmers of the weevil scourge, it doesn't change the fact that their diets are often extremely limited in nature.

In countries where a single crop makes up the majority of the population's food intake, vitamin and mineral deficiencies are rife. The lack of simple micronutrients sees more than 10 million children under the age of five die each year, due to diseases that could have been prevented through better nutrition.

According to the World Health Organisation, dietary vitamin A deficiency also causes 250 000 to 500 000 children to go blind every year, and compromises the immune systems of approximately 40% of children under five.

In an attempt to stem the spread of this preventable but crippling phenomenon, numerous research projects are busy investigating ways to boost the nutritional content of staple foods.

One of the major projects being funded by the B&MGF is the HarvestPlus alliance, a global grouping of research institutions working together to develop high-yield crops for improved nutrition. It focuses on staple foods consumed by most of the world's poor living in Africa, Asia and Latin America.

Funding is spread across several initiatives, including the BioCassava Plus programme, Africa Biofortified Sorghum Project, the ProVitaMinRice project (Golden Rice) and the National Banana Research programme in Uganda.

Why not create a weevil-resistant sweet potato using biotechnology?

Lawrence Kent, Bill & Melinda Gates Foundation

Communities are beginning to see the benefits. HarvestPlus' orange-fleshed sweet potato variety, for example, which contains 50% of the daily vitamin A requirement, has been introduced with great success in Uganda and Mozambique. The B&MGF reports that a study of more than 24 000 households in the two countries found vitamin A intake among young children, older children, and women as much as doubled in homes that grew these new varieties.

While the outcomes are promising, there are still various issues muddying the waters of agricultural biotechnology. Crops can be fortified either through conventional plant breeding or using methods that alter their genes - and the latter has received much negative attention over the years. While the orange sweet potato uses traditional breeding techniques, the Golden Rice and BioCassava Plus crops are genetically modified.

Critics of gene transfer between species argue it could have a negative impact on people's health and the environment, and that further testing is needed before these foods are made available to the public. Opponents also point to the possibility of transgenic crops creating 'super weeds', if genes from the modified crop make their way into other plants. Organic farmers worry about genes spreading to their crops through pollination, while consumer scepticism about 'franken-foods' remains, with groups rejecting GM foods on ethical or religious grounds.

Kent noted in a Nature report earlier this year that "anything that involves biotechnology involves a level of controversy”. He added, however, that the approach needs to be “open and data-focused", and that the B&MGF was working to produce the data required for the two GM crops to meet safety regulations.

In 100 years' time, most of us will be eating GM bananas, papaya and other crops.

Professor James Dale, Queensland University of Technology

Major international groups, including the UN's Food and Agriculture Organisation (FAO) and the World Health Organisation, have recognised the key role biotechnology can play in tackling health and hunger issues, but also stress the need for continuing investigation into potential risks.

But for many countries in the developing world, the threat of widespread hunger often trumps the need for extensive testing, with millions in a desperate condition. As climate change increases the strain on agriculture, so the focus on finding viable solutions intensifies. One potential answer is a new crop aimed at alleviating the effects of extensive, crippling drought.

The Water Efficient Maize for Africa (Wema) initiative is a five-year project which hopes to develop drought-tolerant maize varieties through various biotechnology breeding techniques. Also funded by the B&MGF, the long-term goal is to make this modified crop available royalty-free to small-scale farmers in sub-Saharan Africa.

As the main food source for more than 300 million people in Africa, maize is vital to survival on the continent. However, maize crops suffer from frequent droughts, leading to widespread hunger, as seen in the recent drought in the Horn of Africa.

Led by the African Agricultural Technology Foundation, Wema is undergoing field trials in Kenya, Uganda and SA, with plans for the first hybrids to be available after six or seven years of research and development.

Mass a-peel

Seven billion: what it means for global hunger

The United Nations announced that the global population is set to hit seven billion at the end of October, fuelling concerns about feeding an already starving world.
With one billion people estimated to go hungry each day, this rise in numbers coupled with global economic difficulties is likely to worsen the situation.
While the world produces enough food to feed everyone, many people do not have sufficient land to grow, or income to purchase, enough food, says the UN.
As climate change sees the battle for control over resources intensify, the poor majority faces an even greater challenge when it comes to ensuring sustainable food supply.

That takes care of two staple crops in Africa, and brings us to a humble fruit feeding 100 million across the continent: the banana.

Professor James Dale, director of the Centre for Tropical Crops and Biocommodities at the Queensland University of Technology (QUT), in Australia, believes 'bananas for the 21st century' is a concept that will be realised in the near future.

“In 100 years' time, most of us will be eating GM bananas, papaya and other crops.”

Dale noted that bananas are the second biggest fruit crop in Africa, with the East African region alone producing 16.4 million tonnes per year - about 20% of global production.

“In the western world, we think of bananas as a dessert fruit, but in many parts of the tropics and sub-tropics, bananas are a very important part of people's diet,” said Dale.

Because both male and female domesticated bananas are sterile, conventional breeding of bananas is very difficult. While there have been a few outcomes following this route, they tend to be very long and complicated, he added.

The QUT's banana research programme is trying to genetically engineer nutritionally fortified bananas to make available to farmers in Uganda (the world's second largest banana producer after India). Run in partnership with Uganda's National Agricultural Research Organisation, the project is also being funded as part of the B&MGF's Challenges programme.

The project hopes to grow bananas with higher levels of pro-vitamin A, vitamin E and iron, as the banana variety most commonly grown in Uganda is low in these nutrients. Given each Ugandan eats an average of 1kg of bananas daily, a fortified version could go a long way to reducing deficiencies.

The first field trial began in Australia in 2009, with biofortification methods being tested on Australian Cavendish bananas. Dale said the aim is to develop the technology in Australia, and transfer the techniques, but not the actual plants, to Ugandan scientists for application to their local bananas.

If successful, the project will provide major benefits to all countries in East African that grow the highland bananas, said Dale.

Promising as these developments are, the agricultural biotechnology industry still faces myriad legitimate challenges, from health concerns to regulatory delays. But with news last week that the global population is set to hit the seven-billion mark, nutrient-boosted, pest-resistant and climate-tolerant supercrops may just be the breakthrough needed to finally help poor farmers reap what they sow.

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