The Mango Powdery Mildew Disease is a fungal disease caused by the pathogen Oidium mangiferae, also known as Acrosporum mangiferae. The fungus primarily affects the foliage and fruit of mango trees and can cause significant damage to the tree canopy and fruit yield. Infected trees are also more susceptible to other diseases and pests.
Management of this disease is complex and requires a combination of pruning and removing infected parts, fungicide applications, and cultural practices such as avoiding overhead irrigation, resistant varieties, and crop sanitation. To effectively manage this disease, it is important to understand its disease cycle, the mode of disease spread, and the best methods for controlling it. This article will provide an overview and discussion of the Mango Powdery Mildew Disease in Mango crops, including its symptoms, identification techniques, and control.
Mango Powdery Mildew Disease Management
The Causal Organism of Mango Powdery Mildew Disease
- Oidium mangiferae is an obligate parasite that belongs to the Family Erysiphaceae of Order Erysiphales of the Phylum Ascomycota. Its mycelium is ectophytic.
- Conidia are uni-cellular, barrel-shaped, and produced in bead-like chains. These spores are produced in the spring and cause infections.
- Conidiophores are transparent and short-sized.
The Disease Cycle of Mango Powdery Mildew Disease
The disease cycle of the Mango Powdery Mildew Disease, Oidium mangiferae, in Mango Crops begins when the fungus produces small, powdery conidia (spores) on the surface of the infected plant. These spores are spread by wind, water droplets, and insects and can spread quickly to other parts of the plant. The spores then germinate, forming mycelium (mushroom-like structure), which penetrates the surface of the leaves and petioles to cause infection.
As the infection spreads, the fungus produces white, powdery colonies of mycelium on the surface of the leaves and petioles. These colonies release more spores that the wind can carry to neighboring plants, continuing the cycle. The next cycle stage involves the production of cleistothecia, which are spherical, black bodies found on the powdery colonies. These cleistothecia contain ascospores, which can survive harsh environmental conditions and can be spread to other plants, thus perpetuating the cycle.
The final stage of the disease cycle occurs when the ascospores are released and then germinate on the surface of the foliage. This results in the formation of new hyphae, which penetrate the surface of the leaves and petioles. The fungus then produces more colonies of powdery white mycelium and releases more spores, thus completing the cycle and allowing the fungus to spread and cause damage to the crop.
Occurrence of Mango Powdery Mildew Disease in Mango Crop
- Location of Mango Powdery Mildew disease: This disease occurs in mango crops in India, Bangladesh, Africa, the United States, Mexico, Brazil, Peru, and Ecuador.
- Host range: The most common crops affected by Mango Powdery Mildew Disease are mango, guava, citrus, apple, peach, pear, and loquat.
Favorable Conditions for Mango Powdery Mildew Disease Spread in the Field
- Warm, humid weather, rainy season, and cooler night temperatures at the flowering stage favor the disease transmission
- The fungus grows rapidly in high humidity, cloudy weather, heavier rains, and morning mist.
- The fungus survives as dormant mycelium in the affected leaf buds. The secondary spread of the infection is by air-borne conidia.
- The disease is also favored by overcrowding of plants and poor air circulation in dense plantings. And heavy nitrogen fertilization can cause an increase in the