Traditional crops and animal breeds are disappearing as intensive agriculture advances, particularly in much of the developing world.

As monocultures spread, the soil loses organic matter and, usually, fertility too. Pests become less diverse, but there are more of them. More pesticides and fertilizers are used to counter the changes. This can accelerate soil degradation, and it can make pests and diseases resistant to the chemicals used to fight them. The way to beat them is to interbreed crops every five to 15 years - often with wild strains.

This worked with stripe rust, a wheat disease that reached epidemic proportions in the United States in the 1960s. Montana was losing a third of its crop to the disease each year, but genes from a wild wheat in Turkey provided resistance to it and 50 other diseases, saving millions of dollars a year.

  Similarly, the genetic make-up of maize was strengthened by the 1977 discovery of Zea diploperennis, believed to be maize's ancestor and described as the botanical find of the century. When bred with cultivated strains, it gives resistance to seven major diseases, including a leaf fungus that caused more than $2 billion in losses in the Corn Belt in the 1970s. Even if only 1 per cent of US crops benefits from it, estimates suggest the savings would be $250 million per year.

Unfortunately, as monoculture advances, destroying variety and thus important genetic resources, it kills off its potential saviours.
I. Johnson/UNEP/Topham T. Paramjit/UNEP/Topham

Source: FAO
E. Nizamova





T.W. Waltrip

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