Temperature dependence of net photosynthesis in Trientalis borealis Raf. in Wisconsin.

Multivariate analysis of variance was used in testing 16 gas exchange curves derived from three populations of Trientalis borealis Raf., to demonstrate lack of evidence for ecotypic differentiation with respect to thermal adaptation of net photosynthesis among the populations examined. Limitations of these conclusions are discussed. Although ecotypes within Trientalis borealis may indeed exist, demonstration of their existence requires increase in the precision of experimental techniques, or in sizes of samples that are commonly used in ecophysiological studies of gas exchange capacities of plants.