Denise Bester & Carlin Archer: Seed stores may rescue us from starvation

Genetic diversity is the stuff that evolution is made of. It allows a species to survive by adapting to a constantly changing environment. When a species population size decreases, some of the building blocks of that species are lost, and hence some of its ability to adapt to change is lost.

This diversity within crops is the biological foundation of farming, but the industrialisation of agriculture means that more farmers are relying on fewer high yielding varieties. For example, while probably only six or seven varieties of rice make it on to our supermarket shelves, there are actually over 90,000 varieties of rice, cultivated and wild.

Without a constant infusion of new, hardy genes into our crop species, pests and diseases could quickly get out of hand. Genetic uniformity can allow diseases that are always present at low levels, to get out of control. If an entire field of plants are practically identical, then the crop becomes genetically defenceless, and the only way to build up defences is by introducing new varieties containing different genes into the mix. The recent food crisis scare found world grain stocks at their lowest since the 1970s. This is not a very comforting prospect in a time when extreme climate events are placing food production at a high risk of devastation. To put this into perspective, last year Australia experienced its worst drought for over a century, and saw its wheat crop shrink by 60 per cent. China's grain harvest has also fallen by 10 per cent over the past seven years.

This is where important programmes like the arctic seed vault in Svalbard come in. The Global Crop Diversity Trust, the sole dedicated worldwide funding organisation for the conservation of crop diversity, manages this global seed store which is dug into the side of a mountain 1000km north of Norway. Nicknamed the Doomsday Vault, it is the ultimate back-up system for the world's most important natural resource - food.

Seeds from all areas of the world are stored for posterity, and New Zealand has 25,000 seed varieties in the vault.

Closer to home though, organisations such as the Koanga Institute have taken on the responsibility of collecting and saving the heirloom seeds of this country. They say that since 1920, we have lost around 90 per cent of vegetable and 95 per cent of fruit varieties. Koanga provides guidance on seed storage and is a source of heirloom seeds, only dealing in open pollinated seeds, which means the seeds can continue to propagate from generation to generation.

Cary Fowler, executive director of the Global Crop Diversity Trust, says of diversity: "Think of it as giving us options. That is exactly what we need [to cope with] climate change."

* Denise Bester is from the sustainable living website www.ecobob.co.nz