Neopestalotiopsis zimbabwana

Neopestalotiopsis zimbabwana is a highly destructive fungal pathogen belonging to the order Amphisphaeriales. This fungus is recognized as the causative agent of a severe necrotic disease that significantly impacts agricultural productivity, particularly in strawberry cultivation, where it induces leaf blight, crown rot, and fruit decay.

The host range of this pathogen is primarily focused on strawberries, though it has been identified in various other hosts under specific environmental conditions. Once established, the fungus rapidly colonizes the plant tissues, leading to systemic infection. In agricultural settings, it can cause catastrophic losses in yield and quality if left unmanaged, often leading to total plantation failure within a single season.

Symptoms initially appear as small, circular to irregular lesions on leaves, which gradually expand and become light brown or gray in the center, frequently surrounded by a dark-colored necrotic border. As the disease progresses, these lesions merge, causing the leaf to wither and die. On stems and petioles, the fungus causes dark, sunken cankers that restrict the transport of nutrients, ultimately resulting in the death of the entire plant structure.

The proliferation of the pathogen is driven by high relative humidity and temperatures ranging from 20°C to 28°C. Rain splash, irrigation water, and the movement of contaminated equipment are the primary modes of dispersal. The fungus is highly resilient, capable of surviving in dead organic matter and soil for extended periods, which complicates crop rotation management and soil sanitation.

Effective management requires a combination of strict horticultural practices and chemical control strategies. To mitigate the risks associated with this pathogen, producers are advised to implement the following measures:

• sourcing disease-free planting material from certified nurseries;
• maintaining proper plant spacing to improve airflow and reduce canopy humidity;
• pruning and disposing of infected plant parts to reduce the inoculum pressure;
• implementing drip irrigation to avoid wetting the foliage;
• applying registered fungicides systematically during periods of high disease risk.