Phytochemical comparison of Puccinellia arctica to Poa pratensis, Puccinellia langeana, and Puccinellia phryganodes for evidence of chemical defense

Abstract

Puccinellia arctica is a species of arctic grass that is unpalatable to Canada geese, Branta canadensis, and may be an effective and non-lethal means of controlling the growing populations of urban Canada geese that are problematic in many areas of North America. The secondary metabolite profile of P. arctica was compared to the metabolite profiles of three palatable grass species to determine the plausibility that P. arctica is chemically defended. The volatile and non-volatile secondary metabolite profiles of both P. arctica and the palatable grasses were the same. No alkoloids were detected in any of the grasses. Condensed tannin levels were similar in all of the grasses. Gallotannin levels were higher in the palatable grasses than in P. arctica. However, ellagitannin levels were higher in P. arctica than in the palatable grasses and may be responsible for its unpalatability to Canada geese.