Flower-foraging insects and their pollen loads in french permanent grasslands

International audience; Semi natural grasslands are considered as a vital habitat for wild pollinators, which in return contribute to preserve the floristic diversity of this environment. To study the interactions between pollinators and plants, flower-foraging insects were caught from beginning of May to end of July along three contrasted dairy farming systems in France. Sampling was carried out along six walking transects for each farming system. We developed and test in parallel a method based on DNA barcoding analysis, allowing a quick identification of the insect and its pollen load at the same time. The results from more than 1000 flower visitor insects support the idea that DNA metabarcoding provides accurate information about the plants-insects networks. We showed spatial and temporal variation between the 3 systems and also between the 18 grasslands. DNA barcoding that most of the collected insect carried more than two plant genera. It also pointed out sensitive issues, especially the necessity to build reliable international barcode databases.