Real-time monitoring of oriental fruit moth, Grapholita molesta, populations using a remote sensing pheromone trap in apple orchards

Abstract

A fusion of information technology (IT) and sex pheromone monitoring provides a remote sensing IT-pheromone trap to monitor Oriental fruit moth, Grapholita molesta, populations in apple orchards. Once a male of G. molesta is attracted to its sex pheromone lure in the trap, an infrared sensor installed at the funnel-shaped orifice generates an electric signal. The signal is processed in a central processor and then transferred to an internet site via a code division multiple access protocol. The signal also contains information about when each male is caught. Daily trapping information from different localities is archived in a website. The accuracy of IT-pheromone traps in detecting male catches was shown by a high correlation ( r = 0.956) between the generated IT signals and actual numbers of males caught in the trap in apple orchards. Using this IT-pheromone trap, G. molesta in apple orchards was monitored for one year. These data were compared with monitoring data obtained from a conventional wing type-based sticky trap containing the identical sex pheromone lure. Both showed four characteristic adult peaks from April to September and were significantly correlated ( r = 0.695). IT-pheromone traps also gave real-time signals of male catches in the field. These real-time signals of male catches showed a characteristic diel attraction rhythm from 4 pm to midnight. The diel rhythm of the male response to the sex pheromone started earlier in the evening in the spring season compared to mid and late seasons. This study provides a novel sex pheromone trap for G. molesta to monitor its population in field conditions in real-time without visiting or counting. The field monitoring data can be accessed any time through a designated internet website.