A plant disease in which there is disintegration of the root tissues. Above-ground symptoms are often initially similar to those of nutritional disorders or bad drainage. Annual plants appear sickly and eventually wilt and die as a result of shortage of water and nutrients. Affected trees usually show symptoms of gradual decline and die-back of the crown. Numerous different species of fungus cause root rots. Armillaria mellea (the honey fungus) is a ubiquitous root pathogen affecting many forest and garden trees. Other common root-infecting fungi include Corticium, Phytophthora, and Fusarium. See also take-all. |
