Major Mango diseases are given below:-
1.Mango Anthracnose: Colletotrichum gloeosporioides
- Produces leaf spots, blossom blight, wither tip, twigs blight and fruit rot.
- Small blister like spots develops on the leaves and twigs. Young leaves wither and dry Tender twigs wither and die back symptom appears.
- Affected branches ultimately dry up. Black spots appear on fruits.
- The fruit pulp becomes hard, crack and decay at ripening. Infected fruits drop
- Spray P. fluorescens (FP 7) at 3 weeks interval commencing from October at 5g/like on flower branches.
- 5-7 sprays one to be given on flowers and bunches.
- Before storage, treat with hot water, (50-55°C) for 15 minutes or dip in Benomyl solution (500ppm) or Thiobendazole (1000ppm) for 5 minutes
2.Mango Powdery mildew: Oidium mangiferae/ Acrosporum mangiferae
- It attacks the leaves, flowers, stalks of panicle and fruits.
- Shedding of infected leaves occurs when the disease is severe.
- The affected fruits do not grow in size and may drop before attaining pea size.
- Survives as dormant mycelium in affected leaves.
- Secondary spread by airborne conidia
- Dusting the plants with fine sulphur (250-300 mesh) at the rate of 0.5 kg/tree.
- The first application may be soon after flowering, second 15 days later (or) spray with Wettable sulphur (0.2%), (or) Carbendazim (0.1%),(or) Tridemorph ( 0.1%),(or) Karathane (0.1%).
3.Mango malformation: Fusarium moliliforme var. subglutinans
- Three types of symptoms: bunchy top phase, floral malformation and vegetative malformation.
- In the bunchy top phase in nursery bunching of thickened small shoots, bearing small rudimentally leaves. Shoots remain short and stunted giving a bunchy top appearance.
- In vegetative malformation, excessive vegetative branches of limited growth in seedlings. They are swollen with short internodes forming bunches of various size and the top of the seedlings shows bunchy top appearance.
- In malformation of inflorescens, shows variation in the panicle. Malformed head dries up in black mass and persists for a long time.
- Secondary branches are transformed into number of small leaves giving a witches Broome appearance
- Diseased plants should be destroyed
- Use of disease-free planting material
- Incidence reduced by spraying 100-200ppm NAA during October.
- Pruning of diseased parts along the basal 15-20 cm apparently healthy portions.
- This is followed by the spraying of Carbendazim (0.1%) or Captafol (0.2%).
4.Stem end rot: Diplodia natalensis
- The dark epicarp around the base of the pedicel
- In the initial stage, the affected area enlarges to form a circular, black patch
- Under humid atmosphere extends rapidly and turns the whole fruit completely black within two or three days.
- The pulp becomes brown and somewhat softer.
- Dead twigs and bark of the trees, spread by rains
- Prune and destroy infected twigs and spray Carbendazim or Thiophanate Methyl(0.1%) or
- Chlorathalonil (0.2%) as the fortnightly interval during the rainy season.
5.Mango Red Rust: Cephaleuros virescens
- Algae attack foliage and young twigs.
- Rusty spots appear on leaves, initially as circular, slightly elevated, coalesce to form irregular spots.
- The spores mature fall off and leave cream to white velvet texture on the surface of the leaves
- Bordeaux mixture (0.6%) or Copper oxychloride 0.25%
6.Grey Blight: Pestalotia mangiferae
- Brown spots develop on the margin and at the tip of the leaf lamina. They increase in size and become dark brown. Black dots appear on the spots which are acervuli of the fungus.
- Survive on mango leaves for over a year. Spreads through wind-borne conidia.
- Heavy infection is noticed during the monsoon when the temperature is 20-25oC.and high humidity.
- Remove and destroy infected plant parts.
- Spraying copper oxychloride 0.25 Mancozeb 0.25% or Bordeaux mixture 1.0%.
7.Sooty mould: Capnodium mangiferae
- The fungi produce mycelium which is superficial and dark. They row on sugary secretions of the planthoppers. Black encrustation is formed which affect the photosynthetic activity.
- The fungus grows on the leaf surface on the sugary substances secreted by jassids, aphids and scale insects.
- Management should be done for insects and sooty moulds simultaneously.
- Controlling of insect by spraying systemic insecticides like Monocrotophos or methyl demeton
- After that spray starch solution (1kg Starch/Maida in 5 litres of water. Boiled and dilute to 20 litres)
- Starch dries and forms flake which is removed along with the fungus.
- TamilNadu Agritech Portal