Box 1

Biodiversity and Agriculture

Biodiversity is essential to sustainable agriculture. Species richness helps the agricultural production to adapt to extreme shocks, especially climatic. Studies of grasslands have shown that where greater levels of diversity have been conserved, recovery subsequent to a drought is much more rapid (Tilman and Downing, 1994). The greater the simplification of the genetic base, the greater the risk from pathogens. The likelihood of a pathogen eliminating the resource base and thereby causing major food insecurity is hard to quantify, although it demonstrably occurs, for example in the case of potato blight. Yields in the developing world have dropped and the infestation is threatening to go back to the high Andes, the original center of domestication but also the major reserve of diversity of potato in the world.

Source: Blench 1998