Kernel decay

Kernel decay is a fungal disease caused by various species of Aspergillus. This pathogen is notorious for its ability to colonize agricultural commodities both in the field and throughout the post-harvest supply chain, posing significant risks to food safety and crop quality.

A wide range of crops is susceptible to this disease, including almonds, peanuts, corn, and various oilseeds. In almonds, the infection specifically targets the kernel, making it a critical concern for nut producers aiming to maintain high market standards and prevent the accumulation of mycotoxins.

Typical symptoms involve the colonization of the kernel by fungal mycelium, which often appears as a dusty or powdery growth. Depending on the species of the fungus, the mold coloration ranges from yellow-green to dark brown or black. Infected kernels often exhibit decay, discoloration, and an off-flavor, rendering them unsuitable for commercial use.

The development of kernel decay is highly dependent on environmental factors, particularly high humidity and warm temperatures (typically 25–35°C). Pathogens often gain entry into the kernel through damage caused by field insects, environmental stress, or mechanical harvesting injuries, creating an ideal gateway for fungal spores.

Effective management requires a multi-faceted strategy that begins with controlling pests during the growing season to prevent kernel damage. Furthermore, post-harvest measures such as rapid drying, moisture control, and strictly monitoring storage environments are essential to suppress the growth of Aspergillus spores.

• Maintaining seed/nut moisture levels below 7% during storage.
• Implementing integrated pest management (IPM) to reduce mechanical damage.
• Ensuring proper ventilation and cooling in storage facilities.
• Sanitizing harvesting and processing equipment to minimize spore spread.