UBC Theses and Dissertations
Studies on the probable origin of some European douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) plantations Berney, Jean Louis Ami
In Europe, the origin of older Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) plantations is generally unknown. The tracing of the probable origin of one Swiss and twenty Polish Douglas-fir stands was attempted. Cone and seed characteristics were measured on material collected from all twenty-one European stands, and compared with the displayed variation of the same characteristics from Douglas-fir growing in its natural range on the Pacific Coast of North America. A seed morphology test, as described by Allen (1960), was used to indicate the Coastal or Interior origin of the samples. Based on this test, the stands from Boezingen/Switzerland and from Purda Lesna/ Poland proved both to be of Coastal origin. A direct comparison of averages of six cone characteristics (width and length of cone scale, width of bract, length of first and second prong, and rating of bract) with the ranges of averages of these characteristics as they vary in climatic seed collection zones of the natural range (Yao ) did not allow an unequivocal assessment of origin. From these comparisons, it could be concluded that cone scale and bract width are more influenced by the environment than the other characteristics. The six characteristics of cone morphology, one thousand-seed weight (measured or assessed on 124 samples from the natural range) and relative DNA content (measured on thirty-six samples of the Coastal part of the natural range) were used concurrently to perform discriminant analyses based on different subspecies, climatic and latitudinal groupings. The discriminant functions obtained were then used to classify the twenty-one provenances of unknown origin. Their origin was assessed at the intersection of the groups to which they were attributed in the different analyses. The low number of provenances, when compared with the immense natural range, and the low number of characteristics taken into consideration, did not allow a complete separation of the groups of provenances. Therefore, the assessment of origin based on cone and seed morphology is still to be considered with caution. Pre-established curvilinear regressions of relative DNA content of embryo cells on latitude in both Coastal and Interior Douglas-fir (El-Lakany and Sziklai [1971, 1972]), were used for inverse estimation of the latitude of origin. It could be established, by this method, that the stand from Boezingen/Switzerland originates between lat. 44° and 47°N on the Coast. When samples are sufficient from the unknown stand, as was the case for provenance Boezingen, seed characteristics and relative DNA content gave promising indication of the probable origin.
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