Diseases of fruit plantation medicinal and aromatic crops (2+1)

Citrus sooty mould

Causal organism: Capnodium citris
It is actually not a disease. The fungus purely grows on the host surface consuming insect excreta or honey secretions of insects and plants.Growing of such blacky mold on the plant surface obstructs sunlight to reach to the photosynthetic area (green chlorophyll) of the plant thus interfering the photosynthesis process.
Symptoms


• Black coloured sooty mass can be seen covering the leaf surface and sometimes on young stems and fruit surfaces.
• Black sooty mass contains conidia and mycelia in it affects the normal photosynthesis, process due to which plant growth decreases.
• This is purely ectophytic and not a plant parasitic fungi as this fungus develops on the host surface utilizing leaf exudates and honey like substances secreted by insects and also insect excreta.

Management


• Spraying 1% starch solution causes formation of flakes on the sooty mass which results in removal of sooty mass from the leaves.
• Spraying systemic insecticides like to manage the insects population can also help in avoiding or reducing sooty mold.