Mapping Breakthrough for Plant Insect Bipomes

The take home of course is that DNA extraction of insect stomach contents will now allow us to thoroughly map an insect’s preferred biome right across the whole spectrum of plants and insects.  There will still be omissions, but I think that with some care that those will be scant.

Once understood and fully mapped, both plants and insects will become natural pathfinders to each other.  You also could hardly ask for a better description of a particular biome when you are making plans to manage that biome.

So I expect this work to become profoundly important to establish an economic planning basis

DNA helps unravel relationship between plants and insects

by Staff Writers

Washington DC (SPX) Mar 27, 2013

 This is the rolled leaf beetle C. alternans inside a Zingiberales leaf with its eggs in Costa Rica. Credit: Smithsonian

http://www.terradaily.com/reports/Smithsonian_scientists_use_DNA_to_quickly_unravel_relationship_between_plants_and_insects_999.html

Studying the relationship between plants and the insects that feed on them is an arduous task, as it must be done through direct observation. It can take years for a researcher to fully understand the diets of a community of herbivorous insects in a tropical rain forest.

Now, five Smithsonian scientists are paving a fast track using the DNA found inside the insects' stomachs, potentially turning years of research into months. This method will help scientists understand the ecology and evolution of plant-herbivore interactions more efficiently. Their findings are published in the journal PLOS ONE.

Plants and insects comprise about 50 percent of all known species on Earth, forming the critical foundation of biodiversity in most terrestrial ecosystems. This study focused on 20 species of rolled leaf beetles in Costa Rica and 33 species of flowering plants in the order Zingiberales that the beetles eat and lay eggs on almost exclusively.

Using specialized DNA extraction methods the scientists obtained a mix of DNA both from the actual insect and from the insect's stomach contents. They used DNA markers specific to animals to obtain DNA barcodes for each insect species and markers specific to plants to identify the plant species in each insect's diet.

"What makes this study unique is that we developed DNA extraction techniques and full DNA barcode libraries that allowed us to identify host plants to the species level," said Carlos Garcia-Robledo, a post-doctoral fellow at the Smithsonian and lead author of the study. "Another unique feature of this study is that we invested several years in the field identifying the diets of insect herbivores using direct observations.

This baseline data allowed us for the first time to test the accuracy of DNA barcodes to identify insect diets."

Matched against the data gathered from prior direct observation, the information derived from this DNA stomach-content study was nearly identical, yet had taken only fraction of the time and effort.