Hypovirulence and Chestnut Blight Research: Fighting Disease with Disease

Abstract

Abstract During the first half of this century, the chestnut blight fungus, Endothia parasitica, destroyed stands of the American chestnut, Castanea dentata, throughout the tree's natural range. Conventional methods of controlling plant diseases have been ineffective. An approach being studied is the use of viruslike cytoplasmic hypovirulence agents to reduce the ability of the fungus to cause blight. Individual cankers have been controlled by treating them with strains containing these agents, but neither the agents nor the strains containing them appear to have spread naturally. Persistent cankers containing these agents may be required to provide long-term sources of inoculum for spread.