Final total plant height of Ginkgo biloba L. following 3 years of forced chilling (group one); 1 year of ambient chilling (998 hours) and 2 years of forced chilling (group two); and 2 years of ambient chilling (998 and 1,487 hours) and 1 year of forced chilling (group three).z
| Chill hoursy | Group onex | Group twox | Group three x |
|---|---|---|---|
| 100 | 210 abc | 157 b | 204 b |
| 200 | 188 abc | 203 ab | 187 b |
| 300 | 160 c | 149 b | 214 ab |
| 400 | 166 bc | 200 ab | 200 b |
| 500 | 166 bc | 185 ab | 214 ab |
| 600 | 165 bc | 212 ab | 221 ab |
| 700 | 218 abc | 232 a | 189 b |
| 800 | 223 abc | 208 ab | 203 b |
| 900 | 232 ab | 197 ab | 217 ab |
| 1,000 | 193 abc | 184 ab | 212 ab |
| 1,100 | 244 a | 248 a | 254 a |
| 1,200 | 231 ab | 225 a | 225 ab |
| Regression equation | y = 166.0 + 0.053x | y = 166.3 + 0.052x | y = 192.5 + 0.029x |
| r | 0.40 | 0.41 | 0.34 |
| p-value | 0.005 | 0.004 | 0.017 |
↵zTotal plant height measured in cm from base of the plant to highest possible point, at the end of 3 years, 1999–2002.
↵yChilling was applied to each treatment at 4°C (38°F) in a cooler in 100-hour increments following 200 hours of ambient chilling to ensure dormancy prior to treatments.
↵xMeans within a column with the same letter are similar according to Duncan’s multiple range test (α = 0.05).