Issues Magazine

Garden Variety

By Emile Frison

Crop improvement, environmental sustainability and higher farm incomes all depend on agricultural biodiversity – as does simply consuming a healthy, balanced diet.

Agricultural biodiversity is a source of desirable traits. The genetic basis of disease resistance, for example, is sought from a vast array of agricultural biodiversity and then bred into existing crop cultivars and livestock breeds to create new cultivars and breeds that are better able to thrive under stress. This kind of scientific breeding will remain important as the world grapples with feeding more people a better diet using fewer resources.

Right now, for example, wheat is under threat from UG99 rust, and race 4 of Panama disease could wipe out commercial banana production. Australian wheat farmers, unlike subsistence farmers elsewhere, might be able to afford the fungicides to fight UG99, but there are no suitable treatments for Panama disease. A solution will have to be sought in agricultural biodiversity. However, agricultural biodiversity can also deliver better nutrition, enhanced resilience, greater sustainability and higher farm incomes, all of which are particularly significant for poor smallholder farmers.

Nutrition is perhaps the most important. More than 60 years after the start of the Green Revolution, hunger still stalks around a billion people, and two billion people, mostly young women and children, suffer the “hidden hunger” of micronutrient deficiency. Even wealthy countries like Australia are not immune.

The problem is not simply the lack of proteins or calories, but the lack of diversity in the diet, which is one way to guarantee an adequate supply of micronutrients. Evidence from several studies, mostly in the developed world but increasingly from developing countries, indicates that a diverse diet protects people from several non-communicable diseases and is associated with a longer, healthier, more productive life.

Diseases such as obesity, diabetes, heart disease and cancer were long considered diseases of affluence, but they are spreading quickly in low- and middle-income countries, where 80% of the deaths from them occur. Current approaches to the problems of malnutrition are clearly not working. Agricultural biodiversity offers a fresh approach as the basis of healthy diets and resilient food systems.

In Kenya, people traditionally ate more than 200 species of leafy vegetable. Almost all are much more nutritious than the cabbage and kale that were often the only green vegetables for sale in cities, but their wider use was stymied by perceptions of backwardness, supplies that were erratic and unhygienic, and the ignorance of younger adults, especially in cities, about how to prepare them.

Working with a range of partners, Bioversity International-trained Kenyan farmers learned to grow traditional leafy vegetables and worked on quality control and supply chains. Supermarkets were enlisted to help make the produce available in cities, and colourful leaflets offered recipes for preparing them. Well-known entertainers and government figures endorsed traditional foods on mass media. The result was an increase in deliveries to markets from 30 tonnes per month to 400 tonnes per month three years later. The incomes of farm families supplying the vegetables have increased by between two and 20 times.

The vegetable species and some intervention techniques are specific to East Africa, but the general methods and ideas behind this initiative are applicable globally. Similar projects promoting Andean grains in Bolivia and Peru, nutritious millets in India and Nepal, and nutrient-rich fruits in the Pacific are making considerable headway. The trend towards urban agriculture and locally grown vegetables could be harnessed to provide better nutrition for all.

When the World Health Organization (WHO) and others first sounded the alarm about micronutrient deficiency, they said that dietary diversity was the preferred option for tackling the problem. This original emphasis was slowly overtaken by a much more clinical approach that saw each deficiency as a distinct disease to be cured by a specific supplement. Supplements, fortified foods and biofortified staples currently rule, but the original food-based solutions advocated by WHO and others must be reassessed.

Ecosystem complexity goes hand-in-hand with resilience, and this applies to agricultural ecosystems. Growing different varieties of crop species can control pest and disease outbreaks, and also allows the best use of diverse growing conditions. Access to a range of cultivars gives farmers more options for dealing with capricious weather – a variety that avoids drought or flood by maturing quickly can mean the difference between life and death. Livestock and fish add to human nutrition and can also contribute to soil fertility and farm incomes. Additionally, agricultural biodiversity will be essential for adapting agriculture to climate change.

The multiple benefits of making greater use of agricultural biodiversity in these various ways will be seen in long-term improvements that will be self-sustaining as healthier communities engage in a diversified and less destructive agriculture that offers a nutritionally superior diet, which in turn keeps communities healthier – with profound effects on economic development.