Table 1.
Parameter | Treatments |
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Saranac |
Insaranac |
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+CO2 | –CO2 | +CO2 | –CO2 | |
Shoot dry matter (mg plant−1) | 373±160 | 143*±84 | 243±40 | 253±43 |
Root dry matter (mg plant−1) | 153±56 | 61*±20 | 109±29 | 114±6 |
Nodule dry matter (mg plant−1) | 24.3±9.8 | 12.1±7.9 | 3.7±1.7 | 4.6±2.3 |
Total dry matter (mg plant−1) | 550±220 | 216*±114 | 355 ±70 | 370 ±48 |
Nodule number | 24±19 | 40±11 | 38±15 | 56±40 |
Nodule individual dry weight (mg nodule−1) | 1.60±1.06 | 0.31±0.22 | 0.11±0.07 | 0.12±0.12 |
Plants were grown for 3 weeks with different levels of CO2 concentration in the root/nodule compartment. ‘Insaranac’ forms fix–-nodules. Nitrogen nutrition of ‘Saranac’ depended on nitrogen fixation while ‘Insaranac’ plants received 2.5 mg N d−1 as KNO3. Data are means of four replicates ±sd. An asterisk indicates a statistically significant difference from the +CO2 treatment of ‘Saranac’ or ‘Insaranac’ (t test, P ≤0.05).