Between-clone, between-leaf and within-leaf variation in leaf epidermis traits in Iris pumila clones

The goal of this study was to analyze variation and covariation in epidermal characteristics (epidermal cell density -ECD, stomata density - SD, and stomata index - SI) on Iris pumila clones on between-clone, between-leaf and within-leaf levels. ECD (similar to the pattern previously observed for SD) increased from the base to the top of leaf, while SI remained constant. Results of profile analyses indicated that clones, individual plants whitin clones (ramets), and three successive leaves on the same plant were not significantly different for examined characteristics, but genetic variation for position effect was detected (significant Zone x clone interaction). Results of the contrast analysis confirmed differences between the base and middle leaf positions for ECD (similar to those for SD) as well as between clone variation for those differences. Observed differences between leaf zones and correlations between analyzed traits were mostly consistent with the expansion hypothesis of stomata differentiation.