Research Article

Clone-Specific Response in Leaf Nitrate Reductase Activity among Unrelated Hybrid Poplars in relation to Soil Nitrate Availability

Figure 4

Nitrate reductase activity (NRA) of the five hybrid poplar clones at the two riparian buffer sites. On the left (a), the NRA assay was done in mid-July (July 10 and 11, 2007) and Site x Clone interaction is significant at . On the right (b), NRA assay was done in late August (August 28 and 29, 2007) and Site x Clone interaction is significant at . Vertical bars represent SE of the means.
103878.fig.004a
(a)
103878.fig.004b
(b)