Tropical & Subtropical Fruits

Mango malformation

Production of thick vegetative shoots and transformation of floral parts into a compact mass of sterile flowers.

Two types of malformation

1. Vegetative malformation
2. floral malformation
Vegetative malformation resembles “bunchy top” which may dry and die in due course.
Floral malformation results in enlargement of flowers with new flowers being produced even after fruit set but with less % of hermaphrodite flowers.

Malformed panicles may be

1. Loose
2. Compact.

Malformation is serious in North than in South. It may result in loss of about 50-60% of the total crop. Krishnabhog, Collecter, Langra, Neelum are tolerant (seedling trees are found to be tolerant)
Virus, fungus, mites, nutrients, C/N ratio, carbohydrates, nucleic acids, amino acids, proteins, phenolic compounds, enzymatic activity in the plant, phytohormones and occurance of malformation like substance are all supposed to be the probable causes for malformation.
Control measures

1. Application of plant growth regulators and phenolic compounds (NAA,Ethrel,GA, Paclobutrozol, etc.)
2. Deblossoming: at bud brust stage-ethrel
3. Use of antagonists and antimalformins: Glutahione, Ascorbic acid, Silver nitrate
4. Application of nutrients: High NPK added with FeSO4, Cobalt sulphate
5. Pruning of malformed parts.
6. Application of pesticides: Parathion,Kelthane,Kerathane.
7. Covering panicles with polythene film to raise the temperature around the panicle.

Inspite of this, malformation is still a puzzling problem. It is therefore concluded that malformation can be kept under check by maintaining

1. Orchards cleanly using disease free planting materials only.
2. Regularly inspecting the orchard
3. Regularly removing all malformation parts and
4. Spraying of insecticides after each pruning.