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Untersuchungen zur Genökologie der Douglasie (Pseudotsuga menziesii [Mirb.] Franco).

dc.contributor.advisorHattemer, Hans Heinrich Prof.
dc.contributor.authorKlumpp, Raphael Thomasde
dc.titleUntersuchungen zur Genökologie der Douglasie (Pseudotsuga menziesii [Mirb.] Franco).de
dc.contributor.refereeGruber, Franz Prof.
dc.subject.dnb630 Landwirtschaftde
dc.description.abstractengDouglas-fir performs well at the western slope of the Schwarzwald mountains in southwestem Germany. Unfortunately no records are available today, which can explain the origin of the seeds for those stands. For a decision on the success of those unknown provenances as well as for future treatments a grude knowledge of the origin would provide substantial support. Thus this study aimed in the question, whether Douglas-fir could be devided into topodemes, here called ecotypes, by means of isozyme gene markers. In order to use features of those ecotypes for identification purposes the question arose, whe- ther these features can be found even in provenance trails far from the original habitat. In addition, this study intends to assess the genetic constitution of the Badenian Douglas-f1f stands and to compare those data with American reports. The literatur review deals with theoretical background infonnation in population genetics, reconstruction of descendants as well as biochemestry of the chosen enzymesystems. Special emphasis was given on the question of subdivision of the species into two or three varieties by looking at dendrological traits, terpene analysis and already published isozyme studies. Not only results but also background infonnation of those studies are discussed and a synoptical table of isozyme studies is provided. Horizontal starch gel electrophoresis was used for isozyme analysis. 27 commercial seed lots as well as samples from 11 provenances out of Baden- Württemberg experimental plots were available. In addition, data from isozyme analysis of 104 provenances have been provided by doctors Li and Adams from the Oregon State University , so that two and three data sets were available respectively, which may be used as independant stratified samples. Five enzymesystems were chosen, of which at least one gene locus was known to exhibit varying frequencies of the allelic structure. Repeated grouping of allelic structures of the analysed samples led to subdivision of the whole number of samples into several groups, of which samples were checked to be in geographical neighbourhood of each other. Average values and standard deviations of the allelic structu- re of those groups were scored, which were called "reference structure" of ecotypes. Genetic parame- ters of those ecotypes were tested to be statistically different from each other. Reference vectors were constructed in a new way, regarding standard deviation as bands arround the mean values and using a free arrangement of the vector components for the leading reference vector, so that easy recogniceable reference vectors can be obtained for all ecotypes of one species. Only frequent a11eles or combined alleles are allowed to be selected for reference vectors, in order to ! work with suitable sample sizes. Genetic variation is described using allelic diversity , multiplicity, heterozygosity , intrapopulationdifferen- tiation and populationdifferentiation Dj. Comparison ofreference vectors with population vectors ofthe Badenian stands as we11 as clusteranalysis of population vectors were used for reconstruction of the origin ofthe Badenian Douglas-fIr stands. Descent hypothesis was tested using ecotype specific average populationdifferentiation 0. In a separate study, morphological traits ofDouglas-fir buds were analysed using colour as we11 as figure traits of buds found at the end of twigs of the first and the second order, respectively. Data were scored using "trait structures", where the percentage of each variant of a trait is given. Sturlies on the morphoIogicaI features of buds using sampies of the Baden- Württemberg experimental plots revealed the fact, that typical trait structures for certain regions can be obtained from the combined colour and bud figure traits, analysed by means of factor as well as cluster analysis. A flfSt at- tempt of descent reconstruction was carried out using factor and cluster analysis of trait structures. Physico-chernical studies resu1ted in lists for the gene loci of enzymesystems GOT, mH, LAP , 6-PGDH and SKDH, which allow comparison of alleles for different laboratory recipes. For 6-PGDH-A sub- stantial differences in alleles were found, comparing tris-morpholine with tris-citrate buffers. The reason for this was found in the existence oftwo Alleles A2 and A2', ofwhich the latter can not be separated from A4 by the tris-citrate buffer. As A2' was exclusively found in interiour popu1ations, the compari- son of separation techniques is recommended for descent-tests. Further studies on GOT in Douglas-fir seedlings offered posttranslational modification as explanation for the tripple banded phenotype of GOT -C even in haploid tissue. Tests of different substrates for stai- ning LAP resulted in the recommendation of renaming LAP-A as AMP-A and LAP-B as AMP-C, as several substrates can be used for the products of the different aminopeptidase geneloci. Scoring genetic variation for putative ecotypes resulted in distinct and characteristic levels of genetic diversity as weIl as multiplicity measures. Populations of a central ecotype of coastal Douglas-fir in western Oregon show highest values and those of the southern interior Douglas-fir show lowest values. In addition, those measures exhibit changes according to dynamics in population development. Reference structures were scored and reference vectors were constructed for 10 ecotypes and varieties, respectively: a northem and a southem interior variety , an ecotype from the Blue Mountains in eastem Oregon, a Sierra Nevada ecotype, one of the southem coastal Douglas-fir in California, on central and one northem ecotype of coastal Douglas-fir, one called "Campbell River" further north, one of the Queen Charlotte Sound and one of the northem crest of the Cascades. Discussion of climatological, palaeontological and omithological aspects showed insights of a complex network, in which three jays and several pine species are involved, amongst them Pinus albicaulis, Pinus contorta and Pinus ponderosa. Evidence was found for zoochory having been one of the most important factors for migration of douglas- fIr and gene-exchange between separated populations during the ice-ages and the interglacial. Regions of distinct subspecies of the jay Cyanocitta stelleri being comparable to t! he regions of Douglas-fir ecotypes gave the reason for the conclusion, the bird species may have had the same refuge as Douglas-fir so that both developed together. Furthermore hints of an ancient introgression zone bet- ween coastal Douglas-fir and the interior variety were found, which once may have extended from the Queen Charlotte sound over the Columbia plateau down to the Sierra Nevada. These fmdings led to the conclusion, that the varieties have existed already prior to the pleistocene. Differentiation measures exhibit also characteristic features of the ten ecotypes and varieties, where at the species level southem Douglas-fir was by far distinct from the rest of the species and populations out of the central region at the coast shared most of their genes with all the other populations. Clusteranalysis of genetic distances as well as clusteranalysis of population vectors showed clear patterns of three varieties, the coastal variety , the northem interior and the southem interior variety as well, which can be subdivided into several ecotypes. A second attempt of descent reconstruction using the comparison between reference vectors and population vectors of the Badenian Douglas-fir stands as well as cluster analysis of population vectors enabled to classify the german stands. Two were recognized as central ecotype, two as northern cotype and two as Campbell-River-ecotype. One stand was found to originate from the Willamette valley and for two stands mingling with the northem interior variety was ofhigh probability. As a conclusion, three varieties of Douglas-fir hould be recognized in future. Evolution shaped several ecotypes, which allow descent reconstruction on a regional level. Management of North American forests should be aware of the complex ecosystem and its genetic sustainablity .de
dc.subject.topicForest Sciences and Forest Ecologyde
dc.subject.bk48.00 Land- und Forstwirtschaft: Allgemeinesde
dc.affiliation.instituteFakultät für Forstwissenschaften und Waldökologiede
dc.identifier.ppn773523847 316388238

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