Abstract
BACKGROUND: Plants emit volatile organic compounds (VOCs), which serve as critical cues for herbivorous insects to locate hosts for feeding and oviposition. Understanding how adults identify host plants is essential to develop pest management strategies, particularly for hemiedaphic insects like click beetles, the larvae of which are significant soil-dwelling pests. To investigate click beetle attraction towards plant VOCs and their relevance for oviposition, we tested the attractiveness of constitutive VOCs (emitted by intact plants) and damage-induced VOCs (released by chopped plants) from 11 plant species to male and female Agriotes sputator beetles.
RESULTS: Agriotes sputator beetles exhibit plant species-specific olfactory preferences, which are influenced by beetle sex and female maturity and differ between constitutive and damage-induced VOCs. Female beetles showed the greatest attraction to buckwheat VOCs, especially during their main oviposition period, whereas males were more attracted to clover and ryegrass. EAG recordings show strong female antennal responses to ryegrass, carrot, maize, wild carrot, barley, and buckwheat VOCs, while male antennae responded significantly only to peas. Antennae from female beetles show overall stronger responses to constitutive VOCs than those of males (P = 0.02).
CONCLUSION: These findings facilitate the development of new approaches for Agriotes pest management. Understanding preferred plant VOCs aids in identifying attractive semiochemicals that can be used for monitoring female beetles. Additionally, recognizing attractive plants aids wireworm management by either avoiding them in crop rotations before sensitive crops (thus reducing oviposition) or by attracting beetles to specific areas where they can be targeted by control measures.