FLORAL ANTHOCYANINS FROM 2 MONKEYFLOWER SPECIES WITH DIFFERENT POLLINATORS

Mimulus lewisii and M. cardinalis are closely related, but M. lewisii is pink-flowered and pollinated by bumblebees while M. cardinalis is r ed-flowered and pollinated by hummingbirds. Pollinator preference is b elieved to he due in part to the difference in flower color between th ese two species. Ten anthocyanins are characterized from M. lewisii an d M. cardinalis petal lobes by high performance liquid chromatography (HPLC) and electrospray tandem mass spectrometry (ES/MSMS). Total anth ocyanin concentration in the petals of M. cardinalis is approximately twice as high as that in M. lewisii, and that this difference can be a ccounted for by the presence of two pelargonidin biosides, probably rh amnohexosides, unique to M. cardinalis. Cyanidin biosides comprise 33% of all the anthocyanins in M. lewisii, but only 2.4% of those in M. c ardinalis. (C) 1997 Elsevier Science Ltd.