Age determination of the glassy-winged sharpshooter, Homalodisca vitripennis, using wing pigmentation

Chris Timmons1a*, Aaron Hassell2b, Isabelle Lauziere3c, Blake Bextine1d

1University of Texas, Tyler, 3900 University Blvd., Tyler, TX 75799
2Texas AgriLife Research, 259 Business Court, Fredericksburg, TX 78624
3P.O. Box 61, Harper, TX 78631

Abstract

A red pigment is contained in the wing veins of the glassy-winged sharpshooter, Homalodisca vitripennis (Hemiptera: Cicadellidae). This insect is the main vector of the plant-pathogenic bacterium Xylella fastidiosa Wells (Xanthomonadales: Xanthomonadaceae), the causal agent of Pierce’s disease of grapevines. Over the course of the H. vitripennis lifespan, the red pigment darkens and eventually becomes brown/black in color. These pigments are believed to be pheomelanin and eumelanin, respectively. The age of H. vitripennis can be determined by calculating the amount of red pigment found in the wings by analyzing high resolution wing photographs with image analysis software. In this study, a standard curve for the age determination of H. vitripennis was developed using laboratory–reared insects of known ages varying from 1 to 60 days. The impact of three environmental conditions on these readings was also investigated and found to have little effect on the age determination, and could be easily accounted for. Finally, field collected insects from several Central Texas vineyards were successfully analyzed for age determination suggesting that the annually reported influx of H. vitripennis was composed almost entirely of older insects.

Keywords: insect pigments, vector insects, insect age

Correspondence: a* chris.t.timmons@gmail.com, b hassell02@gmail.com, c mhlauziere@hotmail.com, d bbextine@uttyler.edu, *Corresponding author

Received: 8 June 2010 | Accepted: 8 November 2010 | Published: 1 July 2011

ISSN: 1536-2442 | Volume 11, Number 78

Timmons C, Hassell A, Lauziere I, Bextine B. 2011. Age determination of the glassy-winged sharpshooter, Homalodisca vitripennis, using wing pigmentation. Journal of Insect Science 11:78 available online: insectscience.org/11.78


Figure 1

Figure 2

Figure 3