ARS | Publication request: A MOLECULAR TECHNIQUE FOR THE ANALYSIS OF GRASSHOPPER HOST PLANT USE

Submitted to: Metaleptea
Publication Type: Abstract Only
Publication Acceptance Date: August 1, 2001
Publication Date: September 15, 2001
Citation: Sword, G.A. 2001. A molecular technique for the analysis of grasshopper host plant use. In: Metaleptea, Special Meeting Issue. International Conference on Orthopteroid Insects, August 19-22, 2001, Montpellier, France. p. 71 Poster.

Technical Abstract: An understanding of the ecology and evolution of grasshopper-plant interactions requires knowledge of the specific plants that grass- hoppers consume in natural populations. Microscopic techniques that involve matching the epidermal characters of plant fragments found in grasshopper crops or fecal pellets with those from known plant specimens have been used for the last 40 years to identify components of grasshopper diets. This process can be laborious and sometimes ambiguous, particularly when morphologically similar plants are eaten by early instars. We set out to develop a reliable molecular technique using highly-variable, non-coding plant chloroplast DNA (cpDNA) to identify plants found in grasshopper crops and/or fecal pellets. Here we demonstrate that cpDNA from plants found in crops &feces of grasshoppers as young as first instars can be extracted and amplified via PCR. Fragment Analysis (FA) allows grasshopper diet to be determined by matching unknown cpDNA fragments of a given length extracted from crops or feces with fragments from known plants collected in the grasshopper habitat. FA can detect mixtures of plants within individual grasshopper diets. The use of this cpDNA-based protocol holds promise for future analyses of grasshopper diet in the field.