Table 2.
Carbon, nitrate, assimilated N and K+ for the three species in the different temperatures
| C (%) | Nitrate (%) | Assimilated N (%) | K+ (%) | ||||||||||
| Crop | Night temperature (°C) | Shoot | Root | Stem | Shoot | Root | Stem | Shoot | Root | Stem | Shoot | Root | Stem |
| Lettuce | 18·2 | 40·2 | 39·8 | – | 0·55 | 0·10 | – | 1·8 | 2·6 | – | 5·7 | 2·9 | – |
| 20. | 38·6 | 41·4 | – | 0·77 | 0·09 | – | 2·4 | 2·4 | – | 4·8 | 2·3 | – | |
| 25. | 38·2 | 40·8 | – | 0·95 | 0·22 | – | 2·3 | 2·5 | – | 5·0 | 2·9 | – | |
| 30. | 38·3 | 41·0 | – | 0·66 | 0·20 | – | 2·5 | 2·6 | – | 5·2 | 2·9 | – | |
| 31·3 | 39·6 | 40·2 | – | 0·67 | 0·43 | – | 2·5 | 2·4 | – | 4·9 | 3·7 | – | |
| P value | 0·643 | 0·927 | NA | 0·029* | 0·019 | NA | 0·132 | 0·788 | NA | 0·458 | 0·142 | NA | |
| Tomato | 18. | 37·0 | 40·7 | – | 0·45 | 0·10 | – | 2·1 | 2·3 | – | 4·4 | 4·7 | – |
| 20. | 37·8 | 39·8 | – | 0·36 | 0·07 | – | 1·9 | 2·2 | – | 4·6 | 4·4 | – | |
| 25. | 37·6 | 39·3 | – | 0·38 | 0·09 | – | 2·0 | 2·1 | – | 4·6 | 4·4 | – | |
| 30. | 36·6 | 40·5 | – | 0·26 | 0·11 | – | 1·9 | 2·1 | – | 3·9 | 4·4 | – | |
| 31·5 | 36·7 | 40·5 | – | 0·17 | 0·12 | – | 2·2 | 2·1 | – | 5·3 | 3·3 | – | |
| P value | 0·942 | 0·795 | NA | 0·006 | 0·529 | NA | 0·841 | 0·014 | NA | 0·658 | 0·045 | NA | |
| Soybean | 17. | – | – | 40·2 | – | – | 0·14 | – | – | 1·1 | – | – | 2·4 |
| 20. | 41·1 | – | – | 0·22 | – | – | 3·2 | – | – | 2·4 | – | – | |
| 25. | 40·9 | 37·8 | 38·5 | 0·25 | 0·27 | 0·37 | 2·7 | 2·0 | 1·8 | 1·9 | 6·6 | 3·5 | |
| 30. | 39·9 | 38·1 | 40·1 | 0·40 | 0·27 | 0·27 | 3·1 | 2·2 | 1·3 | 2·6 | 5·5 | 3·0 | |
| P value | 0·049 | 0·878 | 0·577 | 0·03 | 0·875 | 0·340 | 0·566 | 0·478 | 0·455 | 0·712 | 0·511 | 0·404 | |
Some of the samples for soybean were lost. Assimilated N is calculated by subtracting NO3– from total N.
* indicates a quadratic fit. NA = not applicable.