Sudan bollworm

The Sudan bollworm (Diparopsis castanea) is a destructive agricultural pest belonging to the order Lepidoptera and the family Noctuidae. It is recognized as one of the most serious threats to cotton production, particularly within the African continent, where it can cause severe economic losses.

This moth primarily targets cotton plants (Gossypium species). The larvae are highly specialized feeders that focus on the reproductive parts of the plant. While cotton is the primary host, the insect has also been observed utilizing certain wild Malvaceae species as alternative food sources, which aids in its survival between seasons.

The life cycle of the Sudan bollworm is closely synchronized with the phenology of the cotton crop. Adult females lay eggs on foliage near the fruiting points. Upon hatching, the larvae quickly bore into the squares, flowers, or bolls. This endophytic behavior protects them from many environmental factors and standard insecticide sprays.

The economic impact of this pest is severe due to the loss of yield and fiber quality. Feeding by the larvae leads to the shedding of buds and the internal decay of cotton bolls. Bolls that reach maturity often show signs of larval exit holes, which introduce pathogens that stain and degrade the cotton fiber, rendering it unmarketable.

• Implementation of mandatory closed seasons for cotton cultivation.
• Deep plowing to expose and destroy pupae in the soil.
• Use of sex pheromone traps to monitor adult moth activity.
• Timely application of systemic and contact insecticides during egg hatching.
• Destruction of crop residues immediately after harvest to reduce pupal survival.