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You searched for subject:(caninae). Showing records 1 – 3 of 3 total matches.

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Australian National University

1. Ogilvie, Huw Alexander. Evaluating, Accelerating and Extending the Multispecies Coalescent Model of Evolution .

Degree: 2017, Australian National University

So much research builds on evolutionary histories of species and genes. They are used in genomics to infer synteny, in ecology to describe and predict biodiversity, and in molecular biology to transfer knowledge acquired in model organisms to humans and crops. Beyond downstream applications, expanding our knowledge of life on Earth is important in its own right. From Naturalis Historia to On the Origin of Species, the acquisition of this knowledge has been a part of human development. Evolutionary histories are commonly represented as trees, where a common ancestor progressively splits into descendant species or alleles. Time trees add more information by using height to represent genetic distance or elapsed time. Species and gene trees can be inferred from molecular sequences using methods which are explicitly model-based, or implicitly assume or are statistically consistent with a particular model of evolution. One such model, the multispecies coalescent (MSC), is the topic of my thesis. Under this model, separate trees are inferred for the species history and for each gene’s history. Gene trees are embedded within the species tree according to a coalescent process. Researchers often avoid the MSC when reconstructing time trees because of claims that available implementations are too computationally demanding. Instead, the species history is inferred using a single tree by concatenating the sequences from each gene. I began my thesis research by evaluating the effect of this approximation. In a realistic simulation based on parameters inferred from empirical data, concatenation was grossly inaccurate, especially when estimating recent species divergence times. In a later simulation study I demonstrated that when using concatenation, credible intervals often excluded the true values. To address reluctance towards using the MSC, I developed a faster implementation of the model. StarBEAST2 is a Markov chain Monte Carlo (MCMC) method, meaning it characterizes the probability distribution over trees by randomly walking the parameter space. I improved computational performance by developing more efficient proposals used to traverse the space, and reducing the number of parameters in the model through analytical integration of population sizes. Despite its sophistication, the MSC has theoretical limitations. One is that the substitution rate is assumed to stay constant, or uncorrelated between lineages of different genes. However substitution rates do vary and are associated with species traits like body size. I addressed this assumption in StarBEAST2 by extending the MSC to estimate substitution rates for each species. Another assumption is that genetic material cannot be transferred horizontally, but a more general model called the multispecies network coalescent…

Subjects/Keywords: caninae; species trees; phylogenetics; evolution; biology; Markov chain Monte Carlo; Bayesian models

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APA (6th Edition):

Ogilvie, H. A. (2017). Evaluating, Accelerating and Extending the Multispecies Coalescent Model of Evolution . (Thesis). Australian National University. Retrieved from http://hdl.handle.net/1885/143477

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Ogilvie, Huw Alexander. “Evaluating, Accelerating and Extending the Multispecies Coalescent Model of Evolution .” 2017. Thesis, Australian National University. Accessed September 19, 2019. http://hdl.handle.net/1885/143477.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Ogilvie, Huw Alexander. “Evaluating, Accelerating and Extending the Multispecies Coalescent Model of Evolution .” 2017. Web. 19 Sep 2019.

Vancouver:

Ogilvie HA. Evaluating, Accelerating and Extending the Multispecies Coalescent Model of Evolution . [Internet] [Thesis]. Australian National University; 2017. [cited 2019 Sep 19]. Available from: http://hdl.handle.net/1885/143477.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ogilvie HA. Evaluating, Accelerating and Extending the Multispecies Coalescent Model of Evolution . [Thesis]. Australian National University; 2017. Available from: http://hdl.handle.net/1885/143477

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


Swedish University of Agricultural Sciences

2. Werlemark, Gun. Genetic variability and reproductive strategies in Nordic dogroses, Rosa section Caninae.

Degree: 1999, Swedish University of Agricultural Sciences

In the present thesis, I investigate the morphological variation among and within Nordic dogrose species (Rosa section Carzirzae), and the transmittal of morphological characters and molecular markers to interspecific progeny plants. The occurrence of apomixis within the section is also investigated. All species within section Caninae are polyploid and characterised by their unique meiosis with unequal distribution of maternal and paternal chromosomes to their progeny. The pollen parent contributes only seven chromosomes, whereas the seed parent contributes 21, 28 or 35 chromosomes depending on ploidy level. The dogrose species are morphologically rather distinct. Both reproductive and vegetative morphological characters could differentiate among the investigated taxa, with the exception of the two subspecies of R. dumalis, subsp. corifoliia and subsp. dumalis. Rosa rubiginosa appeared to be the most homogeneous of the species, both within and among populations, and R. dumalis the most heterogeneous, both within and among populations. Rosa villosa was heterogeneous among populations but showed high within-population homogeneity. Morphological characters could also separate interspecific hybrids from progeny groups representing the parental species and the influence from the seed parent was apparent as expected from the skewed distribution of chromosomes. The matroclinal inheritance of molecular markers is also very pronounced, since all but two maternal markers were transmitted to all the interspecific progeny plants. In contrast, only approximately half of the paternal markers were transmitted to the progenies. The degree of homology between the constituent genomes in the parents decide to what extent the genetic contribution of the pollen parent will be recognizable in the progeny plant, both in morphological characters and in molecular markers. The genomes could be separated by size polymorphism in their respective NOR sites. Apparently two of the five consituent genomes in one pentaploid plant were never involved in the bivalent formation. Apomixis appears to occur to a limited extent within the dogroses, indicated by elevated pollen via- bility compared to the experimentally derived hybrid plants, and a complete lack of paternal parent-specific molecular marke

Subjects/Keywords: rosa; genetic variation; apomixis; hybridization; scandinavia; Rosa sect. Caninae; Rosaceae; genetic diversity; matroclinal inheritance; apomixis; RAPD; microsatellites; in situ hybridization

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APA (6th Edition):

Werlemark, G. (1999). Genetic variability and reproductive strategies in Nordic dogroses, Rosa section Caninae. (Doctoral Dissertation). Swedish University of Agricultural Sciences. Retrieved from http://pub.epsilon.slu.se/44/

Chicago Manual of Style (16th Edition):

Werlemark, Gun. “Genetic variability and reproductive strategies in Nordic dogroses, Rosa section Caninae.” 1999. Doctoral Dissertation, Swedish University of Agricultural Sciences. Accessed September 19, 2019. http://pub.epsilon.slu.se/44/.

MLA Handbook (7th Edition):

Werlemark, Gun. “Genetic variability and reproductive strategies in Nordic dogroses, Rosa section Caninae.” 1999. Web. 19 Sep 2019.

Vancouver:

Werlemark G. Genetic variability and reproductive strategies in Nordic dogroses, Rosa section Caninae. [Internet] [Doctoral dissertation]. Swedish University of Agricultural Sciences; 1999. [cited 2019 Sep 19]. Available from: http://pub.epsilon.slu.se/44/.

Council of Science Editors:

Werlemark G. Genetic variability and reproductive strategies in Nordic dogroses, Rosa section Caninae. [Doctoral Dissertation]. Swedish University of Agricultural Sciences; 1999. Available from: http://pub.epsilon.slu.se/44/


Swedish University of Agricultural Sciences

3. Uggla, Madeleine. Domestication of wild roses for fruit production.

Degree: 2004, Swedish University of Agricultural Sciences

The utilization of rose hips has a long tradition in Sweden, where they are used for the manufacturing of a popular dessert soup rich in vitamin C. In the mid 1980s a project was initiated at Balsgård, situated in the south of Sweden, with the aim to develop rose cultivars as a field crop for rose hip production. In the present thesis, some aspects of the domestication process in wild roses for fruit production are reported and discussed. Most of the papers concern species within section Caninae. All of these species are polyploid and characterized by their unique meiosis with unequal distribution of chromosomes from the parents to the offspring. The plant breeding program was divided into three steps. In the first step, plant material was acquired from different sources. The second step involved intraspecific and interspecific crosses in section Caninae and the third step concerned intersectional crosses between sections Caninae and Cinnamomeae. Seed germination was studied with different temperature treatments, and differences in amount of germination among the species were noted. Morphological diversity within and between three species, belonging to section Caninae, R. dumalis, R. rubiginosa and R. villosa was investigated. Rosa dumalis demonstrated the most pronounced intraspecific variation, whereas R. rubiginosa was very homogenous. Similar results were obtained when offspring plants were screened for fruit traits, such as fruit weight, % fruit flesh, % dry matter and vitamin C. Matroclinal inheritance was demonstrated with molecular markers (RAPD) in a pair of reciprocal crosses between R. dumalis and R. rubiginosa. The development of colour and some other fruit characteristics during ripening was studied for 6 weeks in R. dumalis, R. rubiginosa and R. spinosissima. For R. dumalis and R. rubiginosa it is possible to use colour as an indicator of optimum harvesting time. In R. spinosissima the fruits should be harvested in the middle of September, when most of the fruit traits have reached an optimum. Seedlings from 11 intersectional crosses (Caninae and Cinnamomeae) were screened for blackspot, leaf spot, powdery mildew and rust. Blackspot was the most severe disease followed by leaf spot, whereas symptoms of powdery mildew and rust were rare.

Subjects/Keywords: rosa; genetic variation; genetic inheritance; fruits; ripening; fungal diseases; antioxidants; Rosa sect. Caninae; genetic diversity; matroclinal inheritance; fruit ripening; fungal diseases; antioxidants

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Uggla, M. (2004). Domestication of wild roses for fruit production. (Doctoral Dissertation). Swedish University of Agricultural Sciences. Retrieved from http://pub.epsilon.slu.se/670/

Chicago Manual of Style (16th Edition):

Uggla, Madeleine. “Domestication of wild roses for fruit production.” 2004. Doctoral Dissertation, Swedish University of Agricultural Sciences. Accessed September 19, 2019. http://pub.epsilon.slu.se/670/.

MLA Handbook (7th Edition):

Uggla, Madeleine. “Domestication of wild roses for fruit production.” 2004. Web. 19 Sep 2019.

Vancouver:

Uggla M. Domestication of wild roses for fruit production. [Internet] [Doctoral dissertation]. Swedish University of Agricultural Sciences; 2004. [cited 2019 Sep 19]. Available from: http://pub.epsilon.slu.se/670/.

Council of Science Editors:

Uggla M. Domestication of wild roses for fruit production. [Doctoral Dissertation]. Swedish University of Agricultural Sciences; 2004. Available from: http://pub.epsilon.slu.se/670/

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