Fusarium oxysporum

Fusarium oxysporum is a fungus that causes wilt disease in more than a hundred species of plants. It does so by colonizing the water-conducting vessels (xylem) of the plant. As a result of this blockage and breakdown of xylem, symptoms appear in plants such as leaf wilting, yellowing and eventually plant death.

Interest in fusarium oxysporum as a pesticide was first raised after the discovery in the 1960s that it was the causative agent in the destruction of the Hawaiin coca population.

The United States government was involved in a controversial program to use fusarium oxysporum for the eradication of coca in Colombia and other Andean countries, but these plans were cancelled by president Bill Clinton who was concerned that the unilateral use of a biological agent would be perceived by the rest of the world as biological warfare. The Andean nations have since banned its use throughout the region. Use of biological agents to kill crops is potentially illegal under the Biological Weapons Convention.