Table 1.
Shoot regeneration in control (−LN) and cryopreserved explants (+LN) after constant temperature preculture (CT, 22°C constant temperature, 7 days) and alternating temperature preculture (AT, 22/8°C day/night temperature, 7 days)
| Preculture | CT | AT | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Regeneration media | Liquid | Solid | Liquid | Solid | |||||
| Accession | LN | S | R | S | R | S | R | S | R |
| S. tuberosum ‘Désirée’ | − | 100.0 | 97.8 | 100.0 | 100.0 | 100.0 | 98.9 | 100.0 | 100.0 |
| + | 70.0 | 12.2 | 48.1 | 19.0 | 88.9 | 23.3 | 73.5 | 44.6** | |
| S. tuberosum ‘King Edward’ | − | 100.0 | 93.3 | 95.8 | 95.8 | 98.9 | 88.0 | 100.0 | 98.6 |
| + | 90.8 | 21.8 | 77.8 | 44.4 | 81.1 | 16.7 | 86.3 | 75.0* | |
| S. acaule | − | 100.0 | 97.7 | 100.0 | 95.6 | 100.0 | 98.8 | 100.0 | 100.0 |
| + | 94.3 | 36.8 | 80.2 | 25.3 | 97.7 | 55.8* | 83.5 | 33.0 | |
| S. demissum | − | 100.0 | 91.2 | 100.0 | 97.7 | 98.9 | 97.7 | 100.0 | 98.8 |
| + | 100.0 | 67.4 | 92.5 | 62.4 | 98.9 | 85.6** | 94.7 | 82.1** | |
| Mean | − | 100.0 | 95.0 | 99.1 | 97.2 | 99.7 | 95.7 | 100.0 | 99.4 |
| Mean | + | 88.7 | 34.6 | 75.6 | 38.4 | 91.6 | 45.2 | 84.8 | 58.7 |
Comparison of survival (S, shoots, leaves and callus, in percentage) and shoot regeneration (R, only shoots, in percentage) using agarose drops in liquid and solid regeneration media. Results are means of three experiments with approximately 30 shoot tips each tested. Mean is calculated from total shoot tip number. Significances are calculated for the comparison within the same media and between precultures (no comparison between S and R). Values in bold with asterisk mark significant changes after AT (*P < 0.05; **P < 0.01)