Blossom blight

Blossom blight is a destructive plant disease primarily caused by fungal pathogens such as Monilinia species or Colletotrichum gloeosporioides. The disease targets the reproductive structures of plants, leading to the rapid decay of flowers and preventing fruit development. Due to its aggressive nature, it can significantly compromise the commercial viability of fruit and forage crops.

The host range for blossom blight is diverse, impacting various economically important plants. Mango (Mangifera indica) is highly susceptible, frequently suffering from severe flower loss due to this infection. Additionally, it affects alfalfa (Medicago sativa), where it impairs floral health, resulting in reduced seed yields and quality, which directly impacts the profitability of agricultural operations.

Symptoms typically manifest as sudden wilting and browning of flowers, which quickly appear scorched. A layer of fungal spores, often grey or tan, may become visible on the dead tissue under humid conditions. If left unchecked, the pathogen can migrate from the floral parts into the pedicels and twigs, creating cankers that serve as reservoirs for the fungus during the off-season.

The development and spread of the disease are heavily dependent on environmental factors. Prolonged periods of high humidity, light rain, and cool to moderate temperatures are ideal for spore germination and colonization. In such climates, the pathogen spreads rapidly via wind-blown spores and splashing water, often infiltrating blossoms during the most critical phases of pollination.

Integrated disease management (IDM) is the most effective approach for mitigating blossom blight. Key measures include:

• Sanitation: Pruning and removing infected branches and mummified fruits to reduce inoculum levels.
• Fungicide Application: Using preventive chemical treatments strictly timed before and during the bloom period.
• Cultural Practices: Improving orchard ventilation and managing canopy density to reduce humidity.
• Vector Management: Controlling insects that facilitate the dispersal of spores within the field.