The main areas where the coca plant is cultivated to meet the demands of the international drug smugglers are Colombia, Peru and Bolivia. Attempts have been made by the governments of those countries to control the illicit supplies by spraying various chemical herbicides over the coca crop fields. But in response the growers usually move their cultivation areas to new locations. and so overcome the threat to their livelihood.
According to a report in New Scientist for March 11, attempts are being made through the United Nations International Drug Control Programme to conduct open field trials using a strain of the fungus Fusarium oxysporum, which is known to attack the roots of coca plants and kill them. However, there are doubts over the safety of the experiment. The strain of Fusarium concerned was discovered in Hawaii and has not yet undergone field trials outside that country. The suggestion that it be introduced into Colombia has aroused considerable protest in view of its possible effects upon important economic crops and the fact that it is known that it can survive in the soil for years.
Trials are proposed to make sure that only the coca plants will be affected, and to formulate the fungus on grains such as those of rice, which could then be applied to fields from an aircraft. It is nevertheless thought highly likely that the fungus would restrict its activities to coca plants and not attack other types of crops.