Growing goodness

A new plant breeding strategy promises to combat malnutrition, reports Yassir Islam.

Four-year-old Immaculate plays happily with her sisters in their family compound, consisting of a handful of thatched mud huts, in eastern Uganda. As the sun drops behind a distant blur of acacia trees, Immaculate crouches and squints, trying to make out the drawing that her eldest sister is scratching out in the dusty earth. As she squints harder, her sisters laugh at her. In protest, Immaculate folds her arms and storms off. Her mother calls out to her to help prepare their supper.

She already knows what they’ll be eating – atap (a traditional staple dish) with peanut sauce. It’s the dry season and it could be months before they have any vegetables to eat again. Soon it will be dark, but for Immaculate it is difficult to see. She is losing her eyesight, an early clinical sign of vitamin A deficiency. If her condition worsens, she could go completely blind.

Immaculate is not alone. According to the WHO, every year, up to half a million children around the world will go blind, simply for lack of vitamin A. About half of these children will die within 12 months of losing their eyesight, mostly due to increased risk of illness and disease, also caused by insufficient vitamin A. Others, with inadequate iron in their diets, may do poorly in school – lack of iron impairs cognitive development – and those who don’t get enough zinc are more susceptible to illness and may suffer from stunted growth. These children are all suffering from micronutrient malnutrition, a lack of those nutrients required in minute quantities by the body for good health.

“The problem is not just restricted to children,” says Howarth Bouis, Director of HarvestPlus, an international alliance of research institutions and implementing agencies that seeks to reduce micronutrient malnutrition by breeding staple food crops rich in vitamins and minerals. “More than two billion people worldwide lack sufficient iron in their diets, and billions suffer from zinc deficiency. This greatly compromises their capacity to work and live life to the fullest, whether as children or adults. When you add hunger, poor sanitation and inadequate health care into the mix, the combination can be deadly.”

Fresh fruits, vegetables, and even dried fish, that could provide Immaculate’s family with the necessary micronutrients, are often available at the nearest trading centre, but they can’t always afford to buy them. They also live several hours walk away. Twice a year, health workers visit the centre, which has a room used as a ‘clinic,’ where they invite parents to bring their children to receive vitamin A capsules. While most children under five in Uganda get vitamin A supplements, those like Immaculate, who live in isolated rural areas, often fall through the cracks. If her mother can afford not to work on the day that the health workers are at the centre, she’ll take her to get a capsule. She knows she should go twice a year, but it takes more than half a day to make the roundtrip and sometimes this just isn’t possible.

For millions of the world’s poorest people, especially those who live in remote regions, staple crops such as rice, maize, and cassava make up the bulk of their diet, day in and day out. And it is these same staple foods that, ultimately, may hold the key to better nutrition and health. Typically, efforts to fight micronutrient malnutrition have centred on fortifying commercial foods and providing vitamin supplements. While these approaches can work, especially in urban regions, they are costly and have not been able to reach all those in need – particularly the poor living in remote rural areas. The HarvestPlus strategy is different. Through a novel approach known as biofortification, staple food crops are bred to contain higher levels of micronutrients. When these biofortified crops are consumed, the micronutrients are absorbed by the body along with other nutrients. As a result people are able to grow and eat for themselves the nutrientrich biofortified foods that they need.

Breeding biofortified crops, testing new varieties, and releasing the most promising ones can take several years. Once these varieties are developed, plant breeders test them in target regions where micro - nutrient malnutrition is high and where the crop is traditionally consumed. The goal is to maintain, or even improve, crop performance in the field, while ensuring that – once harvested and cooked – the crops still provide a viable source of nutrients. Biofortification can also cause colour changes to the food – so convincing consumers to accept these new varieties, and include them in their diets is as critical as developing them.

“This is an unprecedented opportunity to improve micronutrient nutrition among the poor,” says Bouis. “Through HarvestPlus, plant breeders, nutritionists, and marketing and behavioural change experts are all working together to redefine agriculture as a tool for public health.” International donors have also recognised the potential of biofortification. In 2003 The Bill and Melinda Gates Foundation announced a $25 million grant to support HarvestPlus innovations. DFID and other donors have also provided funding. Despite the long gestation period, the potential impact on global hunger could be enormous. Bouis paints such a scenario: “The World Bank estimates that prevalence of irondeficiency anaemia among pre-school children in India is more than 75%, impairing the healthy physical and mental growth we take for granted in the North.

It means that millions of these children are not being reached by conventional strategies. If we can even provide half of their iron needs through biofortification, the impact would be substantial.”

The basic building blocks are already in place. Underused varieties of staple food crops with naturally occurring higher levels of micronutrients are being pulled from publicly-held germplasm banks around the world and crossed with agronomically superior lines. Plant breeders are creating new biofortifed crops that not only grow well and fill empty stomachs, but also provide some of the micro nutrients that are essential to improving nutrition and health.

Results have been promising. Plant breeders have found that staple food varieties can be developed that contain sufficiently enhanced micronutrients levels. An efficacy trial with high-iron rice in the Philippines was credited with improving the iron-status of women. In Africa, another trial confirmed that a betacarotene rich variety of sweet potato, could improve the vitamin A status of children. HarvestPlus is now adapting these new sweet potato varieties to growing conditions in Africa, and to local tastes. While these results are being validated, HarvestPlus scientists continue to make headway in developing more crops that can deliver micronutrients to malnourished people – directly from field to plate. Even to a secluded family compound nestled in the savannah plains of eastern Uganda.