List of abbreviations .......................................... iv
1 Introduction ................................................. 1
Species concepts ............................................. 1
Speciation ................................................... 3
The genus Hordeum ............................................ 4
The New World Hordeum clade .................................. 6
Incongruence between nuclear and chloroplast sequence data ... 7
Objectives of this study ..................................... 8
2 An AFLP phylogeny of the diploid New World Hordeum species ... 9
2.1 Introduction ............................................ 9
The AFLP method ........................................ 10
2.2 Material and Methods ................................... 10
Sampling ............................................... 10
DNA extraction ......................................... 11
AFLP procedure ......................................... 11
Data analysis .......................................... 13
2.3 Results ................................................ 14
Phenetic analysis ...................................... 14
Cladistic analysis ..................................... 16
2.4 Discussion ............................................. 16
Monophyly and taxonomic value of the species ........... 17
Species groups ......................................... 19
Biogeographical implications ........................... 21
3 Phylogeography of the North American Hordeum
brachyantherum group ........................................ 23
3.1 Introduction ........................................... 23
Climatic history of the study area ..................... 23
Principles of phylogeography ........................... 26
Phylogeographic studies on western North American
taxa ................................................... 29
The study group ........................................ 30
Aims of the study ...................................... 32
3.2 Material and Methods ................................... 32
Taxon sampling ......................................... 32
DNA extraction ......................................... 32
PCR amplification ...................................... 32
Data analysis .......................................... 33
3.3 Results ................................................ 35
Outgroup weights ....................................... 36
General geographic patterns of haplotype
distribution ........................................... 36
Nested clade phylogeographic analysis .................. 39
Phylogeographic patterns in the individual taxa ........ 42
3.4 Discussion ............................................. 46
Nested clade analysis and the general patterns of
haplotype distribution ................................. 47
Inferences about the histories of the single taxa ...... 49
Conclusions and outlook ................................ 54
4 Ecological adaptation in three Patagonian Hordeum species ... 56
4.1 Introduction ........................................... 49
4.2 Gene expression analyses ............................... 60
4.2.1 Introduction .................................... 60
Genetic response to abiotic stress .............. 60
Evolution of gene expression .................... 65
4.2.2 Material and Methods ............................ 66
Cultivation of the material and stress
treatment ....................................... 66
RNA extraction .................................. 67
cDNA synthesis and labeling ..................... 68
Macroarray hybridization ........................ 69
Data analysis ................................... 70
4.2.3 Results ......................................... 71
Response to osmotic stress ...................... 72
Response to salt stress ......................... 79
Response to cold stress ......................... 86
Comparison of response to different abiotic
stresses within species ......................... 90
4.2.4 Discussion ...................................... 94
Macroarrays and experiment design ............... 95
Stress response ................................. 98
Outlook ........................................ 102
4.3 Common garden experiment in greenhouses ............... 103
4.3.1 Introduction ................................... 103
4.3.2 Material and Methods ........................... 104
Greenhouse preparation ......................... 104
Measurement of soil salt content ............... 106
Recording of growth and reproduction ........... 106
4.3.3 Results ........................................ 106
Soil salt content .............................. 106
Vegetative growth .............................. 107
Reproduction ................................... 110
4.3.4 Discussion ..................................... 115
4.4 Synthesis of the results from common garden and gene
expression experiments ................................ 117
5 Conclusions ................................................ 120
General patterns ........................................... 120
Speciation modes ........................................... 121
Outlook .................................................... 124
Acknowledgements .............................................. 125
Summary ....................................................... 127
Zusammenfassung ............................................... 129
Literature cited .............................................. 132
Appendices .................................................... 146
Appendix 1. Samples used in chapter 2 ...................... 146
Appendix 2. Samples used in chapter 3 ...................... 147
Appendix 3. ANOVA results for root material under osmotic
stress ......................................... 157
Appendix 4. ANOVA results for shoot material under
osmotic stress ................................. 171
Appendix 5. ANOVA results for root material under salt
stress ......................................... 177
Appendix 6. ANOVA results for shoot material under salt
stress ......................................... 183
Appendix 7. ANOVA results for root material under cold
stress ......................................... 194
Appendix 8. ANOVA results for shoot material under cold
stress ......................................... 198
Eigenständigkeitserklärung .................................... 204
Lebenslauf .................................................... 205
| 
