Morphological variation and floral abnormalities in a trigger plant across a narrow altitudinal gradient

Abstract

Local adaptation in alpine plants has been demonstrated across wide altitudinal gradients, but has rarely been examined across the alpine-to-montane transition that often encompasses only a few hundred metres. Here we characterize morphological variation in leaf and floral characteristics of the trigger plant Stylidium armeria along a narrow altitudinal gradient in the Bogong High Plains in Victoria. Across this gradient, which encompasses the high-elevation limit of this species, linear changes were found for floral scape height, leaf length and flower number. All these traits decreased with increasing altitude, whereas the frequency of abnormal flowers increased. When plants were grown in ..