Temporal response and attraction of Diaphorina citri to visual stimuli

Asthevectoroftheglobaldiseaseofcitrusgreeningorhuanglongbing,Asiancitruspysllids,Diaphorina citri Kuwayama (Hemiptera: Liviidae), are the greatest threat to the worldwide citrus industry. Criticalto management ofD. citriandhuanglongbingis optimizationofsurveillancemethodologies. Although phytophagous insects may find host plants by multimodal cues, some appear to primarily use visual cues. In this study, we examined the behavior of Asian citrus psyllids toward light from light-emitting diodes (LEDs) in the insect visible spectrum. The periodicity of attraction of psyllids to visual cues was evaluated in the field (yellow sticky traps) and laboratory (multi-colored LEDs) with a strong peak ofactivity during the afternoon in both the field and the laboratory (both 14:00 to 18:00 hours). In laboratory evaluations of psyllids to differently colored LEDs, strongest attraction was to LEDs emitting ultraviolet (390 nm), green (525 nm), and yellow (590 nm) light. Male and femalepsyllidsdid notdiffersignificantly in theirresponsestovisual cues. Thesefindingsprovide the basis for formulating better traps that reflect UV and yellow light and potentially incorporate UV LEDsformonitoringpsyllids anda betterunderstandingofAsiancitruspsyllid visualbehavior.