Figure 3.

Xyloglucan-degrading activity in response to canopy light signals. Shown is xyloglucan-degrading activity measured in the top internodes of alpine (top) and prairie (bottom) plants grown for 3 d under low R/FR (white bars) and green shade (gray bars) conditions. Controls (black bars) refer to data from plants grown under normal light conditions (unaltered spectral composition). Data points represent means ± se (n = 3); each biological replicate consisted of internodes pooled from different ramets from different pots. Different letters above each bar indicate statistically significant differences (P < 0.05, Tukey's b test). Experiments were repeated twice with similar results.