Table 2.
Ratio net | |||||
Relative addition rate (g P g–1 P d–1) | N2‐fixation* (µmol N2 g–1 root f. wt h–1) | Net photosynthesis (µmol CO2 m–2 shoot surface area s–1) | Net photosynthesis (µmol CO2 s–1 on total shoot basis) | photosynthesis : N2‐fixation (mmol CO2 µmol–1 N2 ) | Specific leaf area (cm g–1 DM) |
0·03 | 3·02 (0·21)a | 10·6 (2·2)a | 0·47 (0·09)a | 302 (86)a | 103 (6 )a |
0·06 | 3·50 (0·08)a | 9·4 (0·7)a | 0·58 (0·05)a | 158 (14)ab | 134 (6)b |
0·10 | 4·68 (0·53)b | 8·1 (0·5)a | 0·59 (0·06)a | 94 (14)b | 142 (4)b |
Values are means of four observations (± s.e.). Different superscripts within a column indicate differences on a 5 % level.
* Nodules were mistakenly not separated from the roots, thus N2‐fixation could not be calculated on a nodule basis.