Major diseases of Jackfruit are:-
1.Die-back: Botryodiplodia theobromae
- The most of the die-back becomes evident by discolouration and darkening of the bark some distance from the tip.
- The dark area advances and young green twigs start withering first at the base and then extending outwards along the veins of leaf edges.
- The affected leaves turn brown and their margins roll upwards.
- At this stage, the twig or branch dies, shrivels and falls.
- There may be exudation of gum from affected branches. Such branches are often affected by shoot borers.
- Infected twigs show internal discolouration.
- Pruning of infected twigs followed by spraying of Carbendazim 0.1 per cent or Chlorothalonil 0.2 per cent is recommended.
- Controlling shoot borers and shot-hole borers by suitable insecticides is also important in reducing die-back disease
2.Fruit rot: Rhizopus artocarpi
- Young fruits and male inflorescences are badly attacked by the fungus and only a small percentage of the fruits reach maturity.
- Female inflorescence and matured fruits are not usually attacked.
- The disease is a soft rot. A large number of the affected fruits fan off early. In the first stage of attack ·the fungus appears as greyish growth with abundant mycelia which gradually becomes denser forming a black growth.
- The fungus gradually advances until the whole fruit or the entire inflorescence rots and falls off.
- Spray young fruits with Mancozeb 0.25% or Copper oxychloride 0.25 per cent at an interval of three weeks during the months of January, February and March.
- TamilNadu Agritech Portal