Diseases of Sapota

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1. Diseases of Sapota

2. 1. Leaf spot / Phavophleospora leaf spot Phaeopleospora indica : Initially circular spots pinkish in colour appear which gradually turn brownish in colour. Centre of the spot is whitish grey coloured and number of spots are more on leaves.

3. Management Avoid susceptible varieties. Spray [email protected]% or [email protected]% or [email protected]%

4. 2. Pestalotiopsis leaf spot Pestalotiopsis versicolor (Syn: Pestalotia versicolor , P. sapotae and P. podocarpi )

5. Symptoms Small, reddish brown specks on leaf lamina. Spots enlarge, become circular measuring 1 to 3 mm in diameter Fully developed spots show grayish centre and dark brown to reddish margin Minute black fruiting bodies (pycnidia) are seen in the center of spots

6. 3. Flat limb Botryodiplodia theobromae First reported from Maharashtra and Gujarat by Khurana and Singh in 1972

7. Symptoms Branches of affected trees become flat and twisted. Leaves become thin, small and yellow. Cluster of leaves and flowers on affected twigs. Flowers remain infertile. If fruits are set, they are undersized, hard and fail to ripen. Foliage and fruits fall prematurely.

8. 4. Sooty mould Capnodium versicolor

9. Symptoms Disease severity increases in increased population of leaf hoppers, aphids and other insects. Black superficial growth on entire surface of leaves, fruits and twigs. Fungus is not a parasite. It grows on the excreta and honey secretions of insects. Under dry spell such affected leaves curl & shrivel. During flowering time the appearance of the disease results in reduced fruit set. Sooty mass is a superficial growth of the fungus and it multiplies on insect secretions. Impact of this disease on host is photosynthesis activity and yield decreases.

10. Mode of spread Primary source of inoculum: Dormant mycelia Secondary source of inoculum: Air borne conidia: Spread: Insects, Aphids, wind. Epidemiology: Temperature 28-32 ⁰C, 85-90% RH, Warm Weather and susceptible host.

11. Management Sprays of wettable sulphur 0.2% along with insecticide Dimethoate 1.5g/lit Spray of 1% starch solution makes flakes of the fungus and due to small wind falls of from the plant.

12. 5. Red rust Cephaleuros versicolor . The algal disease and it has been observed in India and else where. It is one of the minor disease of importance. Reduction in photosynthetic activity and defoliation as a result of algal attack lower vitality of the host plant.

13. Symptoms The disease is characterized by initial green coloured, circular patches with marginal serrations. The upper surfaces of the spot consist of numerous, unbranched filaments, which project through cuticle. As and when disease advances the organism turns red rusty spots on the leaves and young twig. Spores mature, fall off and leave cream to white velvet texture on the surface of leaf.

14. Epidemiology The disease is more common on close plantation. The zoospores cause initial infection. High moist condition favours development of fruiting bodies of the algae. Management: it is controlled by spraying with Bordeaux mixture 1% or Copper Oxychloride 0.3% or lime sulphur 0.2%.