Visual acuity of Empoasca onukii (Hemiptera, Cicadellidae)

Chang Tan; Xiaoming Cai; Zongxiu Luo; Zhaoqun Li; Chunli Xiu; Zongmao Chen; Lei Bian

doi:10.3390/insects14040370

Visual acuity of Empoasca onukii (Hemiptera, Cicadellidae)

Insects. 2023 Apr 8;14(4):370. doi: 10.3390/insects14040370.

Authors

Chang Tan¹, Xiaoming Cai^{1

2}, Zongxiu Luo^{1

2}, Zhaoqun Li^{1

2}, Chunli Xiu^{1

2}, Zongmao Chen^{1

2}, Lei Bian^{1

2}

Affiliations

¹ Tea Research Institute, Chinese Academy of Agricultural Science, 9 Meiling South Road, Xihu District, Hangzhou 310008, China.
² Key Laboratory of Tea Biology and Resource Utilization, Ministry of Agriculture, 9 Meiling South Road, Xihu District, Hangzhou 310008, China.

Abstract

Empoasca onukii is a common tea plant pest with a preference for the color yellow. Past work has shown that host leaf color is a key cue for habitat location for E. onukii. Before studying the effect of foliage shape, size, or texture on habitat localization, it is necessary to determine the visual acuity and effective viewing distance of E. onukii. In this study, a combination of 3D microscopy and X-ray microtomography showed that visual acuity did not significantly differ between females and males, but there were significant differences in the visual acuity and optical sensitivity among five regions of E. onukii's compound eyes. The dorsal ommatidia had the highest visual acuity at 0.28 cycles per degree (cpd) but the lowest optical sensitivity (0.02 μm²sr), which indicated a trade-off between visual resolution and optical sensitivity for E. onukii. The visual acuity determined from the behavioral experiment was 0.14 cpd; E. onukii exhibited low-resolution vision and could only distinguish the units in a yellow/red pattern within 30 cm. Therefore, visual acuity contributes to the limited ability of E. onukii to distinguish the visual details of a distant target, which might be perceived as a lump of blurred color of intermediate brightness.

Keywords: Empoasca onukii; compound eye; structure; visual ability; visual acuity.

Grants and funding

This research was funded by the Youth Innovation Program of the Chinese Academy of Agricultural Sciences (no. Y2022QC25, China), the Division of Science and Technology of Zhejiang Province (LQ17C040002, China), the National Natural Science Foundation of China (grant no. 31702052, China), and the Young Elite Scientists Sponsorship Program by CAST (2018QNRC001).