ISHS Acta Horticulturae 567: IV International Strawberry Symposium
FACTORS CONTROLLING THE NORTH-EDGE DISTRIBUTION OF FRAGARIA VIRIDIS AND ITS F. VESCA HYBRIDS IN SOUTH FINLAND |
| Author: | H. Ahokas |
| Keywords: | acid rain, Ca:K, ecological amplitude, freezing tolerance, hybrid weakness |
| Abstract:
The occurrence of Fragaria viridis and sterile F. vesca x viridis hybrids at the N edge of the distribution in S Finland, can be explained by high soil Ca, high Ca:K ratio, a lowest temperature of less than –25°C and, after a mean –3.5°C temperature £5 days' lag prior to persisting snow. A high Ca:K ratio seems to increase the freezing tolerance. Weakness and sterility appeared in experimental F. vesca x viridis hybrids. A hybrid swarm declined on an uninhabited islet since 1930. This can be ascribed to leaching due to acid rains from top-soil without sufficient Ca supplying minerals. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
