Fusarium stalk and ear rot

Fusarium napiforme is a species of fungus within the Fusarium fujikuroi species complex, recognized as a primary causative agent of stalk and ear rot in various cereal crops. This pathogen is of significant concern to global agriculture due to its ability to infect plant tissues and produce harmful mycotoxins, which compromise both crop yield and quality.

Corn is the primary host for this pathogen, although it can occasionally affect other grasses. The infection can manifest in various ways, targeting the root system, stalks, and ears throughout the growing season. Early colonization often goes unnoticed until visible symptoms appear during the grain-filling stage, complicating effective field management.

Symptoms of the disease are characterized by the presence of white or pink mycelial growth on ears and stalks. Infected stalks often show internal discoloration and softening, leading to lodging and reduced nutrient uptake. When the ears are affected, the kernels may exhibit rot and discoloration, often accompanied by the accumulation of fumonisins, which are detrimental to livestock health.

The development and spread of Fusarium napiforme are heavily influenced by environmental conditions, particularly high humidity and warm temperatures. The pathogen survives in crop residues and soil, acting as a primary inoculum for subsequent seasons. Insects that feed on maize plants often serve as vectors, creating entry points for the fungus to invade the internal tissues.

Management strategies focus on minimizing the inoculum load and reducing plant stress. Key practices include:

• Rotation of crops to non-host species to break the pathogen lifecycle.
• Utilization of resistant maize hybrids suitable for local climate conditions.
• Seed treatment with appropriate fungicides to prevent early-stage infection.
• Effective management of insect pests that cause physical injury to the plants.