Fig. 2.

Effects of mineral nitrogen (N) supply (0 or 11 mm NO₃⁻), rhizobia (without or with rhizobia inoculant added, -R or +R) and drained or waterlogged conditions on Melilotus siculus (A) shoot N concentration, (B) shoot N content, (C) root N concentration, (D) root N content, (E) nodule N concentration and (F) nodule N content. DM, dry mass. Only plants inoculated with rhizobia formed nodules. Treatments were imposed 23 d after seed imbibition, for 21 d (plants were 44 d old when harvested) (20/15 °C day/night). Plants were grown in vermiculite and provided with a nutrient solution. Values are means ± s.e. (n = 3; one plant from an individual pot was partitioned to provide one replicate of the various tissues measured). For statistics see Tables 1 and 2.