Cletus trigonus

Cletus trigonus is a species of true bug belonging to the family Coreidae, order Hemiptera. This insect is recognized as an agricultural pest in various Asian regions, known for its ability to damage leguminous crops by feeding on the sap of pods and developing seeds during the reproductive stages.

The primary hosts for this pest include soybean, beans, and other related legumes. By utilizing its piercing-sucking mouthparts, the bug extracts fluids from the pods. This feeding activity disrupts the plant's physiological processes, often resulting in shriveled seeds, pod deformity, and overall yield reduction in commercial fields.

The biological cycle consists of egg, five nymphal instars, and the adult stage. The pest overwinters primarily in the adult stage, hiding in plant debris, under tree bark, or in other protected environments near agricultural lands. As temperatures rise during the growing season, they emerge to infest young crops and begin their reproductive cycle.

The severity of damage caused by Cletus trigonus is significant during the pod-filling period. The punctures made by the bug serve as entry points for pathogens, potentially leading to seed rot and reduced market value. Heavy infestations can lead to substantial financial losses, necessitating early detection and timely intervention by agronomists.

Integrated pest management (IPM) is essential for effective control of this bug:

• Maintaining field sanitation by removing weeds that serve as alternative hosts;
• Utilizing deep tillage to disrupt overwintering sites;
• Implementing crop rotation cycles to break the pest's life cycle;
• Applying targeted insecticides when monitoring indicates that population levels have crossed economic thresholds.