Cactus bug

Systematic position: The cactus bug (lat. Chelinidea vittigera) belongs to the order Hemiptera and the family Coreidae. It is a specialized insect known for its host-specific association with cacti, predominantly those within the subfamily Opuntioideae.

Affected crops: The primary hosts are various species of the genus Opuntia. They can severely affect wild cactus populations as well as cultivated specimens in greenhouses, ornamental landscapes, and home collections, causing significant distress to the plants.

Biology and life cycle: The insect undergoes a life cycle consisting of the egg, five nymphal instars, and the adult stage. Females typically deposit eggs in chains or clusters on the spines or surfaces of cactus pads. Nymphs emerge and feed in groups, progressing through several developmental stages before maturing into adults, which often feature a characteristic pale stripe across the pronotum.

Nature of damage and harmfulness: Feeding by both nymphs and adults causes physical damage to the cactus epidermis. As they extract cell sap, they introduce toxins that induce chlorosis, localized yellowing, and eventually tissue necrosis. Severe infestations often lead to structural weakening of the plant and predispose it to secondary fungal or bacterial pathogens, which can result in the loss of entire plant segments.

Control measures: Management strategies include regular monitoring for the presence of adults or their characteristic feeding damage. Manual removal is often effective in small collections. For larger infestations, chemical control using systemic or contact insecticides registered for ornamental plants may be necessary. Preventive measures also involve removing debris around the plants where the insects might seek shelter during the cooler months.