Spectral Sensitivity and Response to Light Intensity of Diaphorina citri Kuwayama (Hemiptera: Psyllidae)

PurposeTo clarify the spectral sensitivity and response to light intensity of Diaphorina citri (Hemiptera: Psyllidae), which is a primary pest of citrus due to its status as a vector of the citrus disease, huanglongbing (HLB), the most serious disease affecting citrus globally.

MethodsSixteen monochromatic lights (ranging from 340 to 689 nm) and six different light intensities (ranging from 1 to 100 lx) were adopted.

ResultsD. citri adults showed a positive phototaxis to a broad spectrum of light, with four peak of sensitivity at 380, 492, 549-568 and 589 nm. UV light (380 nm) elicited the strongest behavioral response from D. citri, with 83.3% of psyllids responding and a mean displacement of 31.3 cm. Both the response rates and displacements in response of D. citri to UV light (380 nm) were significantly higher than the response rates and displacements in the ten other monochromatic light treatments (P<0.05), including 340, 450, 504, 510, 538, 577, 601, 628, 649 and 689 nm. Furthermore, the phototactic response of D. citri to monochromatic light (549 nm) showed an ‘Λ’ shaped curve as light intensity increased. The psyllid response to different wavelengths and light intensities were significantly different (P<0.05).

Conclusion We suggested that UV (380 nm) light source or green-yellow (549-568 nm) and yellow (589 nm) colour trap boards could be used for monitoring and controlling D. citri.