The influence of spatially heterogeneous soil temperatures on plant structure and function [Elektronische Ressource] / vorgelegt von Kerstin Füllner

Sujets

• Biologie

Informations

• Publié par: heinrich-heine-universitat_dusseldorf
• Publié le: 01 janvier 2007
• Nombre de lectures: 29
• Langue: Deutsch
• Poids de l'ouvrage: 2 Mo

Extrait

The influence of spatially heterogeneous soil
temperatures on plant structure and function



Inaugural-Dissertation



zur
Erlangung des Doktorgrades der
Mathematisch-Naturwissenschaftlichen Fakultät
der Heinrich-Heine-Universität Düsseldorf




vorgelegt von
Kerstin Füllner
aus Kranenburg




November 2007 Aus dem Institut für Chemie und Dynamik der Geosphäre, Phytosphäre (ICG 3)
des Forschungszentrums Jülich
























Gedruckt mit der Genehmigung der
Mathematisch-Naturwissenschaftlichen Fakultät der
Heinrich-Heine-Universität Düsseldorf


Referent: Prof. Dr. U. Schurr
Koreferent: Prof. Dr. R. Lösch
Tag der mündlichen Prüfung: 14.11.2007 Contents
Contents

Abstract..................................................................................................................................... 4
Zusammenfassung.................................................................................................................... 5
1. Introduction .................................................................................................................. 6
1.1 Soil temperature and its dynamics ................................................................................. 6
1.2 Plant response to soil temperature.................................................................................. 9
1.3 Challenges in research on plant-soil temperature interactions..................................... 11
1.4 Aim of this study.......................................................................................................... 12
2 Materials & Methods ................................................................................................. 14
2.1 Plant material................................................................................................................ 14
2.2 Growth conditions........................................................................................................ 14
2.3 Measurement of root temperature effects on plant structure........................................ 17
2.3.1 Growth system ..................................................................................................... 17
2.3.2 Experimental design ............................................................................................ 19
2.3.3 Data analyses ....................................................................................................... 20

2.4 Measurement of root temperature effects on root proliferation ................................... 23
2.4.1 Growth system 23
2.4.2 Experimental protocol ......................................................................................... 23

2.5 Measurement of root temperature effects on nutrient uptake kinetics of barley.......... 24
2.5.1 Growth system 24
2.5.2 Experimental design 25
2.5.3 Data analyses ....................................................................................................... 26

2.6 Determining the influence of root temperature & plant structure on nutrient uptake.. 27
2.6.1 Experimental design ............................................................................................ 27
2.6.2 Data analyses 28

2.7 Measuring compounds of the nitrogen metabolism ..................................................... 28
2.8 Statistics ....................................................................................................................... 29
3 Results ......................................................................................................................... 31
3.1 Plant development & plant growth............................................................................... 31
3.1.1 Germination ......................................................................................................... 31
3.1.2 Plant development stages..................................................................................... 31
3.1.3 Leaf structure ....................................................................................................... 33
3.1.4 Biomass of plants compared at the same age ...................................................... 34
3.1.5 Summary.............................................................................................................. 35

3.2 Root morphology of plants compared at the same age ................................................ 36
3.2.1 Root mass distribution with depth ....................................................................... 36
3.2.2 Root surface area distribution with depth............................................................ 37
1 Contents
3.2.3 Root length distribution with depth ..................................................................... 39
3.2.4 Root tissue density & root diameter .................................................................... 40
3.2.5 Root architecture.................................................................................................. 42
3.2.6 Root elongation.................................................................................................... 44
3.2.7 Summary.............................................................................................................. 45

3.3 Carbon and nitrogen in plants compared at the same age ............................................ 46
3.3.1 Carbon content and partitioning .......................................................................... 46
3.3.2 Nitrogen content and partitioning........................................................................ 48
3.3.3 Nitrogen metabolism ........................................................................................... 51
3.3.3.1 Nitrate in plants ................................................................................................ 52
3.3.3.2 Free amino acids in plants................................................................................ 52
3.3.3.3 Proteins in plants .............................................................................................. 54
3.3.4 Summary.............................................................................................................. 55

3.4 Root temperature effects and the variation of plant development stage or age ........... 55
3.4.1 Shoot and root mass............................................................................................. 56
3.4.2 Root morphology of plants compared at the same development stage................ 58
3.4.3 C and N in plants compared at the same development stage............................... 60
3.4.4 Summary 61
3.4.5 Conclusions for interpretation of results obtained with plants compared at the
same age 62

3.5 Nutrient uptake............................................................................................................. 63
3.5.1 Nitrogen uptake ................................................................................................... 63
3.5.1.1 N uptake affected by root temperature............................................................. 63
3.5.1.2 t temperature and structure ....................................... 65
3.5.2 Magnesium uptake............................................................................................... 67
3.5.2.1 Mg uptake affected by root temperature .......................................................... 67
3.5.2.2 perature and structure .................................... 69
3.5.3 Summary.............................................................................................................. 71

4 Discussion.................................................................................................................... 72
4.1 Vertical temperature gradients in soil cause responses at whole plant level................ 72
4.1.1 Variation in time until germination ..................................................................... 72
4.1.2 Accelerated plant development............................................................................ 73
4.1.3 Benefits in plant growth....................................................................................... 74
4.1.4 Changes in carbon and nitrogen partitioning within the plant............................. 76
4.1.4.1 Carbon allocation ............................................................................................. 76
4.1.4.2 Nitrogen allocation........................................................................................... 77
4.1.4.3 Differences in N metabolism 79

4.2 Vertical temperature gradients in soil cause changes in plant morphology................. 80
4.2.1 Changed leaf structure ........................