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Seedling Wilt: Fusarium sp., Colletotrichum sp.,and Rhizoctonia
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Leaf rot: Cylindrocladium quinquiseptatum
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Last Spot, Twig Blight and Flower Bud shedding: Gloeosporium gleosporioides
1. Seedling Wilt: Cylindrocladium sp., Fusarium sp., Colletotrichum sp., Rhizoctonia sp., and Trichoderma sp
Symptom
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Seedling wilt is found mainly in nurseries and causes five to 40% death of seedlings. Leaves of affected seedlings loose natural lustre, tend to droop and ultimately die.
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The root system and collar region of the seedling show varying degrees of, discolouration and decay.
Management
2. Leaf rot: Cylindrocladium quinquiseptatum
Symptom
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It is noticed in the nurseries as well as in the main field both at young and mature stages.
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Infection starts as dark spots at the leaf margin and spreads sometimes with no definite pattern.
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Rotting may be in the whole leaf or at the tip resulting in defoliation.
Management
3. Last Spot, Twig Blight and Flower Bud shedding: Gloeosporium gleosporioides
Symptom
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Necrotic spots of variable size and shapes are noticed on the leaves.
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Severely affected leaves wither, droop down and dry up.
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In nursery seedlings die back symptoms are seen. Twigs are infected as the symptoms extend from the leaves through petioles.
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The affected branches stand without leaves or only with young leaves at tips. Flower buds are attacked by spreading infection from the twigs.
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Shedding of flower buds occurs during periods of heavy and continuous rainfall.
Management
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Spraying 0.25% Copper oxychloride at monthly interval reduces disease intensity, defoliation and flower bud shedding.
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Initial spray is given just prior to flower bud formation and continued till the harvest of buds.
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