MECHANISMS OF POLLINATION: QUANTIFYING INSECT AND PLANT CONTRIBUTIONS ________________________________ A thesis submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Biology at the University of Canterbury by Melissa Ann Broussard ________________________________ School of Biological Sciences University of Canterbury 2017 Table of Contents Table of Contents..................................................................................................................................ii List of Tables.......................................................................................................................................iv List of Figures.......................................................................................................................................v Acknowledgements.............................................................................................................................vi Abstract..............................................................................................................................................vii Chapter I: Introduction.........................................................................................................................1 Outline and objectives.......................................................................................................5 Chapter II: Pollinator behavior influences pollen viability and single-visit pollen deposition across multiple pollinator dependent crops.....................................................................................................7 2.1 Summary...............................................................................................................................7 2.2 Introduction...........................................................................................................................8 2.3 Methods...............................................................................................................................12 2.3.1 Insect behavior........................................................................................................12 2.3.2 Pollen transport.......................................................................................................13 2.3.3 Pollen deposition....................................................................................................14 2.3.4 Statistical analysis of individual datasets (Objective 1).........................................15 2.3.5 Statistical analyses of paired datasets (Objective 2)...............................................17 2.4 Results.................................................................................................................................19 2.4.1 Insect behavior........................................................................................................19 2.4.2 Pollen transport.......................................................................................................21 2.4.3 Pollen deposition....................................................................................................23 2.4.4 Insect behavior versus pollen transport..................................................................23 2.4.5 Pollen transport versus pollen deposition...............................................................23 2.4.6 Insect behavior versus pollen deposition................................................................25 2.5 Discussion..................................................................................................................25 Chapter III: Specialization of pollinator individuals and their body parts promotes species coexistence.........................................................................................................................................29 3.1 Abstract...............................................................................................................................29 3.2 Introduction.........................................................................................................................30 3.3 Methods...............................................................................................................................32 3.3.1 Data Collection.......................................................................................................32 3.3.2 Network Creation....................................................................................................33 3.3.3 Statistical Analysis..................................................................................................34 Question 1: Do plant species partition pollinators at scales finer than insect species? 34 Question 2: Is plant partitioning of insects scale-dependent?................................35 Question 3: What are the effects of partitioning at different scales on species coexistence? ................................................................................................................................36 3.4 Results.................................................................................................................................39 Question 1: Do plant species partition pollinators at scales finer than insect species? 39 Question 2: Is plant partitioning of insects scale-dependent?................................42 Question 3: What are the effects of partitioning at different scales on species coexistence? ................................................................................................................................45 3.5 Discussion...........................................................................................................................46 Chapter IV: Pollen longevity: a systematic meta-analysis.................................................................49 4.1 Abstract...............................................................................................................................49 ii 4.2 Introduction.........................................................................................................................49 4.3 Methods...............................................................................................................................51 4.3.1 Article selection......................................................................................................51 4.3.2 Abstract screening...................................................................................................53 4.3.3 Full-text screening..................................................................................................53 4.3.4 Data extraction........................................................................................................54 4.3.5 Statistical analysis...................................................................................................54 4.4 Results.................................................................................................................................56 4.5 Discussion..................................................................................................................62 Chapter V: Possible mechanisms of pollination failure in hybrid carrot seed and implications for industry in a changing climate............................................................................................................66 5.1 Abstract...............................................................................................................................66 5.2 Introduction.........................................................................................................................67 5.3 Methods...............................................................................................................................70 5.3.1 Plant Material..........................................................................................................70 5.3.2 Plant Fertility Metrics.............................................................................................72 Phenology...............................................................................................................72 Seed Set..................................................................................................................72 Pollen Viability.......................................................................................................73 5.3.3 Plant Attractiveness Metrics...................................................................................74 Nectar Quality........................................................................................................74 Floral Volatiles.......................................................................................................75 5.3.4 Statistical Analysis..................................................................................................78 5.4 Results.................................................................................................................................81 5.4.1 Plant Fertility Metrics.............................................................................................82 Phenology...............................................................................................................82 Seed Set..................................................................................................................84 Pollen Viability.......................................................................................................85