Lepidiota picticollis

Systematic position. Lepidiota picticollis belongs to the order Coleoptera and the family Scarabaeidae. This species is part of the diverse group of scarab beetles commonly referred to as white grubs. Its larvae are well-known subterranean pests that spend their developmental stages in the soil, feeding on the roots of various plants.

Host plants. The primary host of Lepidiota picticollis is sugarcane, where it can cause devastating losses to root systems. However, the pest is known to be polyphagous and can infest various cereals, horticultural crops, and ornamental plants depending on the environmental conditions and host availability in the region.

Biology and life cycle. The life cycle of Lepidiota picticollis typically extends over several years. Adult beetles usually emerge during specific environmental cues, such as the onset of the rainy season. After mating, females lay their eggs in the soil. The larvae go through several instars, living deep in the soil profile and feeding on organic matter and living roots before eventually pupating in specialized earthen cells.

Nature of damage and harmfulness. The larvae are the most damaging stage of this pest. They consume the root system of host plants, which significantly impairs the plant's ability to uptake water and nutrients. The symptoms of infestation include stunted growth, chlorosis, and sudden wilting of the plants. In cases of high larval density, the roots may be completely severed, leading to the death of the crop and large-scale yield loss.

Protection measures. Effective management of Lepidiota picticollis requires an integrated approach to reduce population levels in the soil.

• Application of soil-incorporated insecticides at the time of planting.
• Cultural practices such as crop rotation to disrupt the life cycle of the beetle.
• Utilization of biological control agents, such as entomopathogenic fungi and nematodes.
• Regular monitoring of larval populations in the field to determine the need for intervention.