In all organisms that reproduce sexually, each individual plant or animal contains a different mix of genes. Known as genetic diversity , this incredible variation within species is what allows populations to adapt to changes in climate and other local environmental conditions. Problems of Genetic Uniformity World agriculture will be hard hit of the genes lodged in forests and other wild ecosystems are lost. Time and again, wild tropical species have come to the rescue of their domesticated relatives . Already more than 400 species of crop pests have developed resistance to one or more of the pesticides used to control them.
Genetic diversity can also be critical in controlling disease.
In this case, genetic uniformity allowed a disease that is always present at low levels, even in the best of years, to run wild. Individual plants were virtually identical and thus genetically defenseless. Only introducing new corn varieties containing new genes stopped the fungus in its tracks. In another instance in the United States, the South's sugarcane industry was saved from near collapse by a gene from a wild Asian species. Genes from a single species of wild rice found in India protects Asian crops from the four major rice diseases.