Nematospora

Nematospora is a genus of yeast-like plant pathogenic fungi belonging to the Ascomycota division, order Saccharomycetales. This pathogen is globally recognized as a significant agent of internal seed decay and fruit rot in various leguminous and fruit-bearing crops.

The primary species of concern is Nematospora coryli. It affects a wide range of hosts, including soybeans, beans, hazelnuts, and pistachios. The pathogen is known for its ability to compromise the structural integrity and nutritional value of seeds, often rendering the harvest unsuitable for commercial use.

The biology of Nematospora is fundamentally linked to hemipteran insects, particularly stink bugs (Pentatomidae). These insects act as primary vectors; they introduce the yeast cells into the seed during their feeding process. Once inside the seed tissue, the fungus proliferates, metabolizing stored starch and protein, which leads to tissue necrosis.

Environmental conditions that favor high humidity and moderate to warm temperatures significantly accelerate the development of the infection. The presence of the pathogen is often identified by discolored, shriveled, or bitter-tasting seeds, which reduces marketability and causes massive yield losses for producers.

Management and control strategies are based on integrated pest management (IPM) principles:

• aggressive monitoring and control of stink bug populations during the pod-filling stages;
• timely harvesting to minimize the duration of vulnerability to insect feeding;
• weed management to reduce alternative habitats for insect vectors;
• utilization of resistant or less susceptible cultivars if available;
• rigorous seed cleaning and sorting to remove infested kernels from the harvest.