Leaf Blight
Causal organism: Cecospora jasminicola Symptoms
- Light brown zonate spots appear on the leaves.
- Black and elliptic spots appear on the twigs.
- The affected areas in the twigs become flattened and depressed with raised edges. Such infected twigs dry up.
- In severe cases the whole plant dies.
Etiology
- Conidiophores are olivaceous brown, short fasciculate, sparingly septate and 20 to 40 x 3 µm.
- Conidia are hyaline to pale olivaceous cylindrical, sub fisoid to sub clavate, septate and 40 to 50 x 3 µm
- Mode of survival and Spread:
- The pathogen survives in affected plant parts as dormant mycelia And spreads through airborne conidia.
Epidemiology
- The disease is severe during August to November.
- When there is high humidity and the temperature between 20 and 270 C
Management
- Clean cultivation, i.e. sanitation, includes removal of weeds.
- On fallen leaves or affected plant parts, spray nitrogen solution or bleaching powder to enhance degradation.
- Smear with Bordeaux paste or coc paste.
- Spray thiophonate methyl 0.1 % or mancozeb 0.2 % or cardendazim 0.1 %.
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Last modified: Saturday, 3 March 2012, 7:15 AM