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  • Author: H. Schroeder x
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Abstract

PCR-RFLPs were performed to assess intraspecific variation in the green oak leaf roller, Tortrix viridana. The cytochrome oxidase I and II genes were amplified with universal and self designed primers, respectively, resulting in three PCR-fragments of 802 bp, 729 bp and 680 bp. 29 restrictions endonucleases were tested for variation in these PCR-patterns. Seven of these enzymes were chosen for further research. We found 13 haplotypes in four populations across a total of 436 individuals. In addition all haplotypes were sequenced. More single nucleotide substitutions were detected in the sequences, particularly in the middle of the cytochrome oxidase I gene, missed by the used restriction enzymes. For these markers intraspecific variation in T. viridana is high compared to other insect species. Furthermore we found differences in frequency of haplotypes among the investigated populations which induce that the markers developed so far are suitable for population genetic studies in T. viridana.

Abstract

Several poplar species within a section, but also between sections, are cross-compatible, thus a high number of interspecies-hybrids occur naturally or have been artificially produced during the last 100 years. Very often, systematically kept records on the production or vegetative propagation of poplar hybrids and/or clones have not been available to date. Hence the origin of the poplar plant material used for the generation of hybrids or clones is not quite clear in many cases, thus making the differentiation between the clones a difficult task. Therefore, genetic markers are needed to clearly identify and differentiate the species and hybrids in the genus Populus, including both identification of existing clones and the breeding of new ones. One aspect of this study is therefore to develop molecular markers for the identification and differentiation of species, hybrids, and clones of the genus Populus.

Abstract

Different species of the genus Eucalyptus, originally native to Australia, are being cultivated in different parts of the world due to their fast growth and beneficial wood properties. In Mexico, probably up to 25 different Eucalyptus species (many of them with unknown species declaration) were introduced early in the 20th century. Many Eucalyptus species are cross compatible and information about provenances of the single eucalypt species is rare. In this study, an experimental plantation established in 1984 and located in Northeast of Mexico was chosen as example to re-assign the species name of six randomly selected Eucalyptus trees growing in this plantation. First, a phylogenetic tree was constructed from complete chloroplast sequences of 31 Eucalyptus species available in the NCBI database. The phylogenetic tree includes three of the nine Eucalyptus species known to be introduced to Mexico, namely E. camaldulensis, E. saligna and E. grandis, which belong to a clade named “Symphyomyrts”. By employing combined BLASTN and UPGMA analyses of six chloroplast (cp) regions, three of the six unknown eucalypt samples (Euc4, 5, 6) cluster together with E. microtheca and E. cladocalyx, whereas the other three (Euc1, 2, 3) were more similar to a group containing E. camaldulensis, E. grandis and E. saligna. UPGMA analysis of the ITS region overall shows the same rough clustering, but provide more detailed information for two samples being most likely assigned to E. camaldulensis.