Tip dieback

Tip dieback is a destructive plant disease caused by the fungal pathogen Gibberella intricans. As a member of the Fusarium complex, this fungus thrives by colonizing the vascular tissues of host plants, eventually causing internal structural damage and restricted nutrient flow. It is recognized as a significant threat in tropical and subtropical agriculture.

The disease is particularly problematic for mango trees (Mangifera indica), where it manifests as the rapid necrosis of terminal shoots. Beyond mango, the pathogen exhibits a broad host range, infecting various agricultural crops, including cereals and other fruit-bearing species, which makes it a persistent challenge in diverse orchard and field environments.

Symptoms typically begin at the tips of the shoots, showing chlorosis followed by rapid browning and wilting. As the disease progresses, dark lesions appear on the stems, often encircling the branch and killing all distal growth. Under humid conditions, the presence of the fungus might be confirmed by visible mycelial growth on the affected woody tissues.

The development and spread of Gibberella intricans are highly dependent on high humidity, rainfall, and moderate temperatures. The fungus enters the plant through wounds caused by insects, pruning tools, or environmental stress. Dense canopy structures and poor airflow in plantations exacerbate the spread, allowing the inoculum to move efficiently between healthy and infected branches.

The economic impact of tip dieback involves substantial yield losses and potential tree mortality if left unmanaged. Preventive strategies are critical, such as maintaining rigorous orchard sanitation, sterilizing pruning equipment, and applying preventive fungicides during the flushing periods of the trees. Early detection and the prompt removal of infected materials are essential to containing the spread of the pathogen.

• Pruning affected branches
• Regular fungicide application
• Sterilization of pruning tools
• Managing orchard ventilation