The silverleaf whitefly, Bemisia tabaci biotype B, is one of the most destructive agricultural pests in the world, vectoring a large number of devastating viruses, including Tomato Yellow Leaf Curl Virus (TYLCV). When selecting a host, B. tabaci is influenced by a range of visual and olfactory cues. Therefore, elucidating how such cues become modified in the presence of whitefly-vectored begomoviruses is critical to better understand the epidemiology of many economically important diseases. The goal of this study was to determine how both visual and odor cues interact in the presence of TYLCV. In Y-tube olfactometer assays, whiteflies were submitted to a range of isolated visual and olfactory cues to determine behavior involved in host selection. B. tabaci choices were then compared to both odor and visual cues combined in the presence or absence of TYLCV. Overall, B. tabaci exhibited a visual attraction to the color yellow, TYLCV-infected tomato leaves, and TYLCV-infected tomato volatiles. Attraction of B. tabaci to an olfactometer arm was the strongest when both visual and olfactory cues from TYLCV-symptomatic tomato plants were combined, as opposed to a single isolated cue. In addition, B. tabaci’s behavioral patterns differed depending on the plant host’s stage of TYLCV infection and the infection status of the insect itself. These results highlight the importance of the interaction between visual and odors cues during B. tabaci host selection in the presence of an associated begomovirus.
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