Ganoderma Wood-Rotting Fungi on Citrus Stumps1

Wood-rotting fungi are present in Florida citrus groves as well as in other citrus-producing regions around the world. Some of the early reports by Reichert (1932) described a problem associated with fine-textured soils where wooden stakes of chestnut, oak or eucalyptus infected with wood-rotting fungi were used to brace up citrus trees on sweet lime rootstock in Palestine. In Florida, L. C. Knorr (1973) identified Ganoderma sessilis, currently synonymous with G. lucidum, as a fungal agent that invaded healthy citrus wood and was also isolated from trees with heart rot. In south Texas, Skaria and Farrald (1989) reported ‘Marrs’ early orange trees on sour orange rootstock were infected with G. lucidum when replanted into a freeze-killed grove in 1984. Prior to planting the new trees, the freeze-killed trees were cut off above the soil line, leaving the stump