Behavioral selectivity of adults of 6 stored-grain insect species for different odorant compounds

Utilizing volatile bioactive compounds to trap stored-grain insects plays a vital role in population dynamic monitoring and the application of trap-and-kill control technologies for stored grains. In this study, a Y-tube olfactometer was adopted to determine the behavioral selectivity of adults of six stored-grain insect species, including Sitophilus oryzae, Tribolium castaneum, Lasioderma serricorne, Cryptolestes ferrugineus, Tribolium confusum, and Sitophilus zeamais, to seven odorant compounds (2-ethylhexanol, jasmone, 2-ethylhexyl benzoate, α-ionone, β-ionone, β-damascenone, and eugenol), at five dose levels. The results showed that the adults of the six stored-grain insect species exhibited species-specific behavioral responses to the seven odorant compounds, with a certain degree of dose dependence.The results indicated that the behavioral responses of adults of the six stored-grain insect species to the seven odorant compounds exhibited significant interspecific differences and obvious concentration dependence.S. oryzae exhibited high choice rates to 2-ethylhexyl benzoate (5 μg/cm² filter paper), jasmone (0.05 μg/cm²), and α-ionone (0.05 μg/cm²), with corresponding choice rates of 78.74%, 77.58%, and 76.71%, respectively. T. castaneum displayed weak overall tropism, yet it had relatively strong responses to β-damascenone (0.5 μg/cm²) and jasmone (0.005 μg/cm²); the corresponding response rate and choice rate reached 81.67% and 63.33%, 50.00% and 61.76%, respectively. L. serricorne was sensitive to β-damascenone (0.05 μg/cm²), α-ionone (0.005 μg/cm²), and 2-ethylhexyl benzoate (0.005 μg/cm²), with choice rates of 76.16%, 69.20%, and 62.58%, respectively. C. ferrugineus produced strong responses to 2-ethylhexyl benzoate (0.05 μg/cm²), with a response rate of 73.33% and choice rate of 73.70%. T. confusum presented strong tropism to β-damascenone (0.5 μg/cm²) and jasmone (0.05 μg/cm²), with choice rates of 62.27% and 62.35%, respectively. S. zeamais exhibited prominent responses to 2-ethylhexyl benzoate (5 μg/cm²), α-ionone (0.05 μg/cm²), and jasmone (5 μg/cm²), with choice rates of 81.11%, 79.01%, and 78.71%, respectively. Overall, most treatments inducing strong insect responses fell within the concentration range of 0.005-0.5 μg/cm² on filter paper, while several compounds still maintained high choice rates at the concentration of 5 μg/cm². These findings provide a basis for the targeted screening of attractants, dose optimization, and development of green monitoring, prevention and control technologies for stored-grain insects.