| Title: | "Diel periodicity and visual cues guide oviposition behavior in Phlebotomus papatasi, vector of old-world cutaneous leishmaniasis" |
| Author(s): | Shymanovich T; Faw L; Hajhashemi N; Teague J; Schal C; Ponnusamy L; Apperson CS; Hatano E; Wasserberg G; |
| Address: | "Department of Biology, University of North Carolina at Greensboro, 235 Eberhart Bldg., Greensboro, North Carolina, United States of America. Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, North Carolina, United States of America" |
| DOI: | 10.1371/journal.pntd.0007165 |
| ISSN/ISBN: | 1935-2735 (Electronic) 1935-2727 (Print) 1935-2727 (Linking) |
| Abstract: | "BACKGROUND: Phlebotomine sand flies are vectors of human leishmaniases, important neglected tropical diseases. In this study, we investigated diel patterns of oviposition behavior, effects of visual cues on oviposition-site selection, and whether these affect the attraction of gravid Phlebotomus papatasi (Scopoli), the vector of old-world cutaneous leishmaniasis, to olfactory cues from oviposition sites. METHODOLOGY/PRINCIPAL FINDINGS: To evaluate these questions, we conducted a series of experiments using attraction and oviposition assays within free-flight test chambers containing gravid females entrained under a 14:10 hrs light:dark photoperiod. By replacing sticky-screens or moist filter papers every three hours, we showed that oviposition site search occurs mainly in the latest part of the night whereas peak oviposition occurs during the early part of the night. Behavioral responses to olfactory oviposition cues are regulated by time-of-day and can be disrupted by transient exposure to a constant darkness photoperiod. Gravid females, but not any other stage, age, or sex, were attracted to dark, round oviposition jars, possibly resembling rodent burrow openings. This visual attraction disappeared in the absence of an illumination source. Egg deposition rate was not affected by jar color. Olfactory cues had the strongest effect when the visual cues were minimal. CONCLUSION AND SIGNIFICANCE: Our study showed, for the first time, that visual cues in the form of oviposition-site color, lighting level, and photoperiod are important in guiding the oviposition behavior of phlebotomine sand flies. Furthermore, such visual cues could modify the flies' sensitivity to olfactory oviposition cues. Our results suggest that chemosensory and visual cues are complementary, with visual cues used to orient gravid females towards oviposition sites, possibly at long- to medium-ranges during crepuscular periods, while olfactory cues are used to approach the burrow in darkness and assess its suitability at close-range. Implications to sand fly control are discussed" |
| Keywords: | Animals Circadian Clocks Color Female Humans Insect Control Insect Vectors/anatomy & histology/*physiology Leishmaniasis/*transmission *Oviposition Phlebotomus/anatomy & histology/*physiology *Photoperiod Sex Attractants; |
| Notes: | "MedlineShymanovich, Tatsiana Faw, Lindsey Hajhashemi, Nima Teague, Jimmie Schal, Coby Ponnusamy, Loganathan Apperson, Charles S Hatano, Eduardo Wasserberg, Gideon eng R01 AI123327/AI/NIAID NIH HHS/ Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't 2019/03/06 PLoS Negl Trop Dis. 2019 Mar 5; 13(3):e0007165. doi: 10.1371/journal.pntd.0007165. eCollection 2019 Mar" |
