Rusty millipede

Trigoniulus lumbricinus, commonly known as the rusty millipede, is a species of millipede belonging to the family Pachybolidae (order Spirobolida). Originally native to Southeast Asia, this species has become a significant invasive pest in many tropical and subtropical regions across the globe, frequently invading agricultural landscapes.

The pest primarily targets a variety of crops, including root vegetables like potatoes, carrots, and sweet potatoes, as well as the seedlings of ornamental plants. While they naturally feed on decaying plant material, they readily turn to healthy, living roots and tubers when their populations explode or environmental conditions become stressful.

The biological cycle of the rusty millipede is strictly dependent on soil moisture and organic matter content. They reproduce throughout the year in greenhouses or warm climates, laying eggs in clusters within the soil. The juveniles go through several molting stages, gradually expanding their population density in favorable environments with high humidity.

The damage caused by Trigoniulus lumbricinus is characterized by deep feeding lesions and tunnels bored into tubers and roots. These wounds do not only reduce the aesthetic and marketable value of the harvest but also serve as entry points for secondary pathogens like fungi and bacteria, leading to rot and total crop failure in severe cases.

• Maintain proper soil drainage to discourage population growth.
• Clear crop residues and organic litter from fields to reduce food sources.
• Utilize bait traps made of slices of potato or cucumber buried in the soil.
• Apply soil-drenching insecticides registered for use against soil-dwelling pests.

Integrated pest management remains the most effective approach. By combining physical sanitation, such as removing debris, with chemical controls only when necessary, growers can successfully manage infestations and minimize the impact of these millipedes on overall agricultural productivity.