Green rose chafer

The green rose chafer (Macrodactylus virens) is a beetle species belonging to the family Scarabaeidae and the order Coleoptera. Recognized by its distinct greenish-olive color, this pest is a significant threat to various agricultural and horticultural systems. It acts as a primary phytophage, focusing its feeding activity on aerial parts of plants while its larval stage affects the root zone.

This beetle targets a wide range of host plants, including fruit trees, grapevines, and various ornamental species. It is particularly damaging during the spring and early summer months when plants are in their most active vegetative state. By feeding on tender leaves, flower buds, and young fruits, the beetle interrupts the plant's physiological processes, leading to reduced vitality and significant harvest losses.

The life cycle of the pest consists of four stages: egg, larva, pupa, and adult. The larval stage spends its time in the soil, feeding on organic matter and small rootlets. This subterranean phase makes detection difficult until adult beetles emerge. Upon emergence, the adults seek food and mates, often clustering on host plants to feed collectively, which can lead to rapid localized defoliation.

Damage caused by Macrodactylus virens is characterized by skeletonized leaves, where only the veins remain. Beyond foliage destruction, the pest often consumes the reproductive parts of the plant, preventing fruit set. High population densities can lead to severe economic damage, as entire branches or small plants may be completely stripped of foliage within a short timeframe.

Management and control strategies are essential to minimize agricultural impact:

• Soil cultivation practices, such as plowing, to disturb and eliminate overwintering larvae in the ground.
• Timely application of selective contact or systemic insecticides during peak adult activity periods.
• Use of light traps and pheromone monitoring to detect and reduce the initial population size.
• Promoting biodiversity in and around the field to encourage the presence of natural predators.