Ganoderma Root-Rot Diseases of Citrus
Ganoderma Root-Rot (Ganoderma lucidum): The disease appears in the soil in one or more of the lateral roots. Whitish strands of fungus spread along the surface of the bark of the roots, which later turn dark. Gradually, the fungus spreads to the bottom of the main trunk. The affected tissues become very light, swollen and spongy due to water accumulation. During rainy season bracket-like fungal fructifications appears at the base of the trunk.
Control : Removal of dead or decaying old stumps from the orchard, treating the basal portion of the stakes with a fungicide and periodical collection and destruction of brackets near the collar controls the disease. Isolation of infected trees by digging a trench all-round the tree to prevent the diseased roots from having contact with the healthy roots and mixing. 0.5 to 1 kg of powdered Sulphur with the soil in the trench helps in controlling the disease. Application of Aureofungin solution (1.5 g in 5 litres of water) and Vitavax (500 ppm) in plant basin is effective