Floral biology, breeding system, pollination and reproductive success of selected understory tree species in fragments of Atlantic rainforest in Pernambuco, Northeast Brazil [Elektronische Ressource] / vorgelegt von Marcus Braun

Informations

• Publié par: universitat_ulm
• Publié le: 01 janvier 2010
• Nombre de lectures: 71
• Langue: English
• Poids de l'ouvrage: 2 Mo

Extrait

Institut für Systematische Botanik und Ökologie
Universität Ulm



Floral Biology, Breeding System,
Pollination and Reproductive Success of
Selected Understory Tree Species in
Fragments of Atlantic Rainforest in
Pernambuco, Northeast Brazil



Dissertation
zur Erlangung des Doktorgrades Dr. rer. nat.
der Fakultät für Naturwissenschaften, Universität Ulm

vorgelegt von
Marcus Braun
aus Bad Segeberg

2010








































Amtierender Dekan: Prof. Dr. Axel Groß

Erstgutachter: Prof. Dr. Gerhard Gottsberger

Zweitgutachter: Prof. Dr. Manfred Ayasse



Tag der Promotion: 10.06.2010
2
Table of contents

Acknowledgments ................................................................................................6
Summary...............................................................................................................8
Zusammenfassung ..............................................................................................14

1. General Introduction..................................................................................21

1.1 Fragmentation and pollination......................................................................21
1.2 Pollination biology: state of knowledge for the Annonaceae and Violaceae
families .........................................................................................................24
1.3 The study area...............................................................................................25
1.4 Aim and outline of the thesis........................................................................25

2. Floral biology, visitor abundance and reproductive success
of Anaxagorea dolichocarpa (Annonaceae) in Atlantic forest
fragments of Northeast Brazil…………………… …… ……… . 27

2.1 INTRODUCTION ........................................................................................27
2.2 MATERIAL AND METHODS....................................................................29
2.2.1 Study species and populations...................................................................29
2.2.2 Flower morphology and breeding system..................................................29
2.2.3 Anthesis, scent production and thermogenesis..........................................30
2.2.4 Seed dispersal and germination .................................................................31
2.2.5 Phenology of tree individuals and subpopulations ....................................32
2.2.6 Flower visitors, pollinator abundance and fruit set ...................................32
2.3 RESULTS.....................................................................................................33
2.3.1 Flower morphology and breeding system..................................................33
2.3.2 Anthesis and stages of flowering...............................................................34
2.3.3 Floral scent and thermogenesis..................................................................36
2.3.4 Seed dispersal and germination .................................................................37
2.3.5 Flower, bud and fruit production...............................................................40
2.3.6 Flower visitation, fruit set and fragment size ............................................42
2.4 DISCUSSION...............................................................................................44
2.4.1 Flower biology and pollination..................................................................44
2.4.2 Visitor abundance, fragmentation and seed production ............................47
2.4.3 Outlook ......................................................................................................49

3. Who pollinates tropical woody Violaceae? The cases of
Paypayrola blanchetiana and Amphirrhox longifolia…… 51

3.1 Introduction...................................................................................................51
3.2 Material and Methods...................................................................................52
3.2.1 Study species .............................................................................................52
3.2.2 Anthesis, floral morphology and P/O ratio................................................53
3.2.3 Scent production ........................................................................................54
3.2.4 Nectar production ......................................................................................55
3.2.5 Breeding system and fruit set ....................................................................56
3.2.6 Flower visitation ........................................................................................56
3.2.7 Pollen germination experiment..................................................................57
3
3.3 RESULTS..................................................................................................... 57
3.3.1 Anthesis, Flower Morphology and P/O Ratio........................................... 57
3.3.2 Floral scent ................................................................................................ 59
3.3.3 Nectar ........................................................................................................ 62
3.3.4 Breeding system and natural fruit set........................................................ 64
3.3.5 Flower visitation........................................................................................ 64
3.3.6 Pollen germination experiment ............................................................... 667
3.4 DISCUSSION .............................................................................................. 67
3.4.1 Flower characteristics and floral visitors .................................................. 67
3.4.2 Fruit set and pollination in P. blanchetiana .............................................. 69
3.4.3 Pollinators of A. longifolia ........................................................................ 70
3.4.4 Are nectar and scent production affected by fragmentation?.................... 72

4. Effect of forest fragmentation and patch flowering intensity on
reproductive success of Paypayrola blanchetiana (Violaceae) in the
Atlantic rainforest of NE Brazil 73

4.1 INTRODUCTION........................................................................................ 73
4.2 MATERIAL AND METHODS ................................................................... 76
4.2.1 Plant Material ............................................................................................ 76
4.2.2 Flower, fruit and seed sampling ................................................................ 77
4.2.3 Data Analysis ............................................................................................ 78
4.3 RESULTS..................................................................................................... 80
4.3.1 Autocorrelation of plant individuals ......................................................... 80
4.3.2 Plant dbh, flower and fruit production ...................................................... 80
4.3.3 Sub-population flower production and resulting fruit set ......................... 81
4.3.4 Fruits/flower and seeds/ovule ratios (reproductive success) in large and
small fragments .................................................................................................. 83
4.3.5 Seeds per fruit in large and small fragments ............................................. 83
4.3.6 Influence of predictors on fruit set and seed set........................................ 84
4.4 DISCUSSION .............................................................................................. 86
4.4.1 Resource availability................................................................................. 86
4.4.2 Patch flowering intensity and fruit set....................................................... 86
4.4.3 Pollinator service, low fruit set…and inbreeding ?................................... 87
4.4.4 Fruit and seed production in large and small fragments ........................... 88
4.4.5 Conservation issues................................................................................... 90

5. Fruit production of Cymbopetalum brasiliense (Annonaceae) in the
absence of pollinators in an Atlantic forest fragment in NE Brazil 92

5.1 INTRODUCTION........................................................................................ 92
5.2 MATERIAL AND METHODS ................................................................... 93
5.2.1 Study species and population .................................................................... 93
5.2.2 Flowering p