Four-spotted beetle

The four-spotted beetle (Popillia quadriguttata) is a destructive species within the scarab beetle family (Scarabaeidae), classified under the order Coleoptera. Closely related to the Japanese beetle, this insect is recognized as a significant agricultural pest due to its wide range of host plants and its ability to rapidly multiply under favorable climatic conditions.

The beetle poses a threat to a variety of agricultural and horticultural crops. Adults primarily feed on the foliage, flowers, and fruits of deciduous trees, ornamental plants, and various field crops. Simultaneously, the larval stage remains in the soil, where it feeds on the root systems of grasses and young seedlings, which often leads to poor development or even the total death of the crop.

The insect undergoes a complete metamorphosis: egg, larva, pupa, and adult. The adult beetles are most active during warm summer days, when they congregate on plants to feed and mate. Females oviposit in moist, organic-rich soil. The larvae, or white grubs, develop over one or more years, depending on environmental temperatures, causing continuous damage to the underground parts of the plants.

The damage caused by adults is characterized by skeletonized leaves, where only the veins remain, and heavy destruction of floral structures, which directly reduces fruit and seed yield. Infested plants show signs of severe stress, including stunted growth and wilting. When the population density is high, the impact on agricultural production can lead to significant economic losses for farmers.

Effective management requires an integrated approach. Cultivation techniques such as deep plowing in late summer or autumn disrupt the pupal stage and reduce the larval population. Chemical control involves the application of appropriate insecticides during the peak activity of adults. Additionally, biological control agents, such as specialized nematodes or bacteria, are used to manage the soil-dwelling larval population.

• Regular monitoring of adult activity using traps.
• Strategic use of insecticides during the bloom period.
• Soil management to reduce organic debris accumulation.
• Implementation of biological pest control agents.