Diseases of Fruit Plantation Medicinal and Aromatic Crops

White thread blight

Causal organism: Marasmius scandens
Symptoms

• The young branches of the infected plants contain white mycelial threads of the fungus which spread longitudinally and irregularly along the surface of the stem.
• On the leaf lamina it spreads in the form of much branched fine threads.
• The fungus invades the cortical tissues which eventually turn dark brown to black. The diseased leaves also turn dark brown.
• The dead leaves in a branch eventually get detached from the stem but are found suspended by the mycelial thread in a row.
• The extensive death of the young branches & suspended leaves in a row are the common field symptoms of white thread blight.
Epidemiology

• High humidity, less aeration and sunlight due to thick shade are the pre disposing factors for the occurrence of white thread blight disease.
• Mode of spread & survival
• The disease spread from plant to plant and different branches of the same plant through the mycelium.
• The dead leaves with the mycelial mat can be easily carried by wind on to the leaves and stems of the healthy plants & initiate the disease.
• Damage can be reduced by removing dead materials and pruning of affected parts.
• Shade regulation and structural pruning of some branches are necessary to reduce humidity in the canopy and the disease.
• Paste with copper oxychloride at cut ends.
• Bio control agent Trichoderma viridae application in the soil
Management
• Damage can be reduced by removing dead materials and pruning of affected parts.
• Shade regulation and structural pruning of some branches are necessary to reduce humidity in the canopy and the disease.
• Paste with copper oxychloride at cut ends.
• Bio control agent Trichoderma viridae application in the soil