Document Type : Scientific article
Authors
1
M.Sc. of Forestry, Natural Resources and Geosciences Faculty, Shahrekord University, Shahrekord, I.R. Iran
2
Assistant professor, Forest science department, Natural Resources and Geosciences Faculty, Shahrekord University, Shahrekord, I.R. Iran
3
Natural Resources Department, Fars Agricultural and Natural Resources Research and Education Center, AREEO, Shiraz, I.R. Iran
4
Associate Professor, Fisheries and Forestry department, Faculty of Agriculture & Natural Resources, Gonbad Kavous University, Gonbad Kavous, I.R. Iran
Abstract
The current experiment was done on Cypress, as one of the most important species in urban forestry, to provide a hydrothermal time model under controlled conditions in a laboratory. The model is designed with respect to stress tolerance thresholds for seed germination. Five different temperature (10, 15, 20, 25, 30 C°) and drought (0, -0.5, -1, -1.5 and -2 MPa) treatments were applied on the seeds. The optimum temperature (To) and basic temperature (Tb) were obtained 21/05 C° and 6/041 C° respectively. The hydrotime constant (θH) for this species was 0/35. The results showed that the decreasing in water potential and temperature caused germination percentage decrease. Temperature and water potential factors had independent and interaction effects significantly on time and percent germination. Finally hydrothermal time model is provided for the species.
Keywords
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