Mango powdery mildew

Mango powdery mildew, caused by the fungal pathogen Oidium mangiferae, represents a significant constraint to mango production worldwide. As an obligate parasite, this fungus relies on the host's living tissues to complete its life cycle, causing severe damage to both vegetative and reproductive structures.

The primary host for this disease is the mango tree (Mangifera indica). The pathogen is particularly destructive when it attacks inflorescences and young fruit, which are the most susceptible stages of development. It can lead to complete yield failure if environmental conditions favor rapid pathogen progression.

The symptoms are marked by the appearance of a powdery white mycelial mat on leaves, panicles, and tender fruits. Infected panicles may turn black and fail to produce fruit. As the infection progresses, affected tissues lose their vitality, leading to leaf distortion, premature fruit drop, and stunted shoot growth.

The development of the disease is heavily dictated by environmental factors, particularly high relative humidity and moderate temperatures. The conidia of the fungus are dispersed efficiently by wind and rain splash, allowing the infection to spread rapidly throughout an orchard, especially in areas with poor ventilation.

Management practices for mango powdery mildew involve a combination of chemical control and orchard sanitation. Fungicides containing elemental sulfur or modern systemic agents are effective if applied during the early stages of disease onset. Pruning to maintain an open canopy is essential to reduce humidity levels around the foliage.

• Early detection during the flowering stage is critical.
• Use of systemic fungicides to prevent mycelial development.
• Pruning trees to improve sunlight penetration and air movement.
• Eliminating debris to reduce primary inoculum sources.