| LEAF BLIGHT (LB): Lasiodiplodia theobromae |
Symptom:
- Leaf blight causes serious damage in seedlings, leaves and nuts of adult palms.
- Generally the adult leaves in the outer whorls are affected.
- The affected leaflets start drying from the tip downwards and exhibit a charred or burnt appearance.
- Dark grey to brown lesions with wavy to undulated margins appear from the apex of the nuts.
- The fungus entered in to the kernel through mesocarp, resulting in a decay of the endosperm.
- The affected nuts were desiccated, shrunken, deformed and dropped prematurely and resulting in nut yield loss up to 10 to 25%.
- The incidence was noticed throughout the year and maximum incidence was observed during summer months.
- Spores and the resting structures on the affected portion of the leaves served as inoculum for further spread through wind.
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| Drying of leaf tips |
Burnt appearance |
Infected kernel |
Infected tree |
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Management:
Cultural method
- Remove and burn the severely affected leaves to avoid further spread.
Biological method
- Application of 200g Pseudomonas fluorescens along with 50 kg of FYM+ 5 kg of Neemcake/ palm/ year.
Chemical method
- Spray 1.0 per cent Bordeaux mixture or 0.25 percent Copper oxychloride (2 times at 45 days interval during summer months).
- Root feeding of Carbendazim 2 g or Hexaconazole/ Tridemorph 2 ml + 100 ml water (3 times at 3 months interval).
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