Gardening Lessons

A poetry collection centered on the poet\u27s childhood trauma and reclamation of body and gender identity through transition

Anthurium Fragrance, Genetic and Biochemical Studies

The total of 147 Anthurium species and hybrids at the University of Hawaii and the Missouri Botanical Garden germplasm collections was evaluated for the presence or absence of scent, type of fragrance, time of emission, daily occurrence, developmental stage of scent emission, color of spathe and spadix. A majority of inflorescences (76%) emitted scent. Scent was categorized as citrus, fishy, floral, foul, fruity, menthol, minty, pine, spicy and sweet. There was no relationship between scent production or scent quality with flower color or botanical section. A plurality of inflorescences emitted scent during the morning (45%) and at the pistillate stage (77%). Fragrance life of unharvested inflorescences varied from 2 to 3 days up to 4 weeks, whereas that of harvested inflorescences was only 1 or 2 days. F1 progenies of crosses between fragrant x fragrant and non-fragrant x fragrant parents were studied to determine whether a single gene or more than one gene governed presence of scent. Progenies from 24 crosses were tested by Chi-square analysis for a single dominant or recessive trait. None produced expected segregation ratios for a single gene trait, indicating that multiple genes likely govern presence of fragrance in Anthurium. Progeny also segregated for fragrance quality and included non-parental scents. Fragrance of seven Anthurium species and ten hybrids was analyzed by gas chromatography and mass spectrometry. Nineteen monoterpenes (lipids) and some alcohols, aldehydes and esters were identified. Limonene and 1,8-cineole were common to most samples along with a-pinene, p-pinene, myrcene and linalool. Hybrid UH1299, emitting a sweet and floral scent all day, showed fluctuation in amounts and types of compound during the daily cycle. Tepals were associated with fragrance production in Anthurium. Histological comparison between tepals of fragrant and non-fragrant spadices showed lipids and starches present in both fragrant and non-fragrant samples. However, in fragrant samples, the amount of lipids was significantly greater than that of non-fragrant ones, whereas the amount of starch was significantly greater in non-fragrant samples compared with fragrant ones. These data support the hypothesis that high levels of lipids were associated with fragrance production

Pollination ecology and the floral reward of Vaccinium myrtilloides and V. vitis-idaea (Ericaceae)

The goals of this research project were to investigate aspects of pollination biology of two native boreal species: Vaccinium myrtilloides (Canadian blueberry) and Vaccinium vitis-idaea (lingonberry) in central Saskatchewan. Accordingly, surveys of insect taxa visiting the flowers were performed, and determination of the effectiveness of these insect taxa to serve as pollinators was measured through pollen deposition and pollen tube growth in the style. Accompanying fieldwork, and morphological and anatomical studies were done for the two food rewards offered by flowers of both Vaccinium species: pollen released through poricidal anthers and nectar secreted from the nectary atop the inferior ovary. Pollen-ovule (P/O) ratios were determined for the two study species in Saskatchewan (V. myrtilloides, V. vitis-idaea) as well as for five other Vaccinium species from eastern Canada (Nova Scotia – V. angustifolium, V. boreale, V. caespitosum, V. corymbosum, and V. uliginosum). Pollen, released at maturity as tetrads, were converted to total pollen grains per flower to yield P/O ratios ranging from 238 (V. caespitosum) to 2,008 (V. vitis-idaea), but 736 for the latter in Saskatchewan. These P/O ratios are indicative of a breeding system ranging from facultative autogamy to facultative xenogamy. Additionally, the structure of mature stamens and pollen tetrads was studied in V. myrtilloides and V. vitis-idaea. Each anther was functionally bilocular; had a single-cell thickness (i.e., epidermis) with regularly occurring papillae; lacked an endothecium; and possessed two distal, hollow tubules each terminating in a pore. Overall pollen grain viability was 76-97% (V. myrtilloides) and 51-93% (V. vitis-idaea), with about 20% of tetrads having only 1-3 grains viable, and 12% and 27% of tetrads entirely non-viable in V. myrtilloides and V. vitis-idaea, respectively. Pollen tetrads occasionally were connected by a sticky substance resembling pollenkitt, but viscin threads were absent. One instance of precocious (in situ) germination of tetrads was recorded within anthers of V. myrtilloides. The floral nectary was a disk of secretory tissue situated between the stamens and the style. The epidermis possessed solitary stomata that were variable in number, but not different between V. myrtilloides and V. vitis-idaea. The nectary was vascularized by phloem alone; many traces were found for V. myrtilloides throughout the nectary, whereas V. vitis-idaea had few traces at the nectary base, concentrated at the inner side of the disk closest to the style base. Young sclerenchyma cells were found throughout the nectary parenchyma. Nectar production started on the day of anthesis for both species, although many flowers of V. vitis-idaea appeared to have no measureable nectar at that time. V. myrtilloides produced a larger range of nectar solutes per flower (0 - 3684.1 μg), than V. vitis-idaea iii (1.29 to 1147.62 μg) over both years; nectar volumes per flower never exceeded 5 μL. Nectar was measured daily in flowers aged 1 – 4 days in 2010 and 1 – 6 days in 2011, however, over the two years at the same study site there was no clear pattern of secretion and reabsorption throughout flower life for V. myrtilloides, and only a gradual increase for V. vitis-idaea as flowers aged. Insect visitors to flowers surveyed in 2010 included a large proportion of honeybees (Apis mellifera) as visitors to both species, whereas in 2011 there were no honeybees present at the field site. There was a larger proportion of hoverflies (Syrphidae) found on the flowers of V. vitis-idaea than on V. myrtilloides. Other visitors to V. myrtilloides were bees (Bombus, Andrena, Osmia, Colletes) and wasps (Vespidae), whereas flowers of V. vitis-idaea were visited by bees (Bombus, Andrena, Osmia, Lasioglossum, Colletes, Hylaeus), an ant (Formicidae) and a butterfly (Lycaenidae). Bombus spp. were shown to be pollinators of V. myrtilloides. Andrena spp. were probable pollinators, whereas honeybees appeared to be poor pollinators. Bombus spp. seemed probable pollinators of V. vitis-idaea and hoverflies to be barely more than visitors, though small sample sizes did not allow for conclusive evidence. The time that an insect spent on a virgin flower had no relationship to the pollination result. Among individuals of various Bombus spp. that did or did not sonicate flowers of V. myrtilloides, the action of “buzz pollination” was shown to result in an increase in the number of pollen tetrads deposited and in pollen tube growth

The evolutionary ecology of floral scent in Hesperis matronalis: assessing the potential for pollinator-mediated natural selection.

Heritable trait variation and differential fitness among trait variants are conditions required for pollinator-mediated natural selection on attractive traits like floral scent. However, previous studies of floral scent have focused on assessing evolution through stereotypical pollination syndromes and often fail to evaluate the conditions of natural selection. I assess the potential for pollinator-mediated natural selection on the floral scent of color polymorphic Hesperis matronalis (Brassicaceae). A study that assessed the importance of shared biochemistry between floral scent and color found significant diurnal variation in scent emission and a population-specific effect of floral color on floral scent composition. Specifically, purple morphs tended to be similar, while white morphs tended to differ significantly. A survey of five wild populations across part of H. matronalis's introduced range supported this trend, particularly for aromatic composition; both scent composition and overall emission rates varied among populations. An experiment comparing scent profiles of plants grown in a common garden environment suggested both environmental and genetic causes of among-population variation. A three-part study assessed the relationship between scent and fitness. Experimental augmentation of floral targets with color-specific floral scent revealed increased syrphid fly visitation in response to increased scent emission rate, predicting a positive linear relationship between plant fitness and emission rate. An experiment limiting pollinator access to plants showed this expected relationship for plants exposed to diurnal pollinators, but no relationship for plants exposed to night pollinators. In contrast, I found a negative quadratic relationship between daytime emission rate and fitness across plants in four large wild populations, suggesting possible costs of scent production under wild conditions, i.e., attraction of herbivores or energetic expenditures.Overall, this dissertation suggests strong potential for pollinator-mediated natural selection on H. matronalis floral scent. Additionally, the results illustrate the importance of assessing all conditions necessary for natural selection of floral scent rather than relying on the observational pollination syndrome framework to describe the evolutionary trajectory of a species

Cy Twombly. Image, Text, Paratext

The artworks of the US artist Cy Twombly (1928–2011) are considered to be hermetic and inaccessible. Pencil scribblings, explosions of paint, tumbling lines, overlapping layers of color, and inscriptions, geometrical figures, numerals, rows of numbers, words, fragments of quotations, and enigmatic work-titles present very special challenges to both researchers and viewers. In the interdisciplinary and transcultural research method of the Morphomata International Center for Advanced Studies at the University of Cologne, a conference was held in June 2012 that brought art historians together with renowned scholars of Egyptology, Archaeology, German, Greek, English, Japanese, and the Romance languages, i.e. all the fields and cultural spheres that were a source of inspiration for the œuvre of Cy Twombly. While these scholars inquire into the relation between title, work, and inscribed quotations, leading representatives of research on Twombly focus on the visual language and scriptural-imagistic quality of Cy Twombly’s work. Through comprehensive interpretations of famous single works and groups in all the artistic media employed by Twombly, the volume’s cross-disciplinary view opens up a route into the associative-referential visual language of Cy Twombly

The characterisation of heritage vegetables

A collection of heritage variety accessions were characterised using Amplified Fragment length Polymorphisms (AFLPs) (200 accessions ) and multivariate analysis of morphological characters (366 accessions); key features of interest for the conservation of Plant Genetic Resources were the identification of diversity within and between accessions. Motivations and practices of heritage variety growers were explored using questionnaires. Heritage varieties are herein defined as traditional crop varieties that have a historical origin of over 40 years, are non-hybrid and non-GMO and are of cultural/heritage value to their users; they are part of the suite of plant genetic resources currently utilised by growers and of potential use to plant breeders in the future. A large range of morphological and genetic diversity was present between accessions in all crops; in addition, diversity was found within accessions, particularly in Vicia faba, Daucus carota and Cucumis sativum. Comparisons between data sets were made for diversity, relationships, comparisons with commercial standards and identifying potential duplicates. The synthesis of both data sets highlighted the three potential duplicates for further investigation by HSL (all in Pisum sativum). The findings highlight the importance of heritage varieties and the Heritage Seed Library, both culturally and in terms of conservation for present and future use

Exploring Plant-Pollinator interactions: critical studies for the safeguard of wild Apoidea and spontaneous plant populations

The study of plant-pollinator relationship and the degree of their specialization is among the most lively and debated issues in plant biology and ecology. The fates of plants and bee pollinators are strictly connected: the severe decline lately encountered by wild Apoidea, which in turn results in a lower pollination rate, trigger the so-called “extinction vortex” phenomenon. This study was finalized to improve knowledge on plant-pollinator interactions, in ecological context with conservation needs. Field work on the natural populations of Dictamnus albus allowed us to define practical methods for the joint protection of wild Apoidea and endangered plants applicable in several contexts. In order to define the pollinator importance of single taxa and of the whole pollinator guild of D. albus, an index distinguishing between potential (PPI) and realized (RPI) pollinator importance was created. Moreover, it was assessed the effect of some abiotic and biotic factors on the abundance and activity pattern of flower-visiting insect groups. Laboratory experiments on Gentiana lutea nectar pointed out a gender-specific amino acid solution preference in Bombus terrestris, one of the main pollinator of this plant, and confirm a negative influence of high amino acid concentration diet on insect mortality. The behavioural study showed that β-alanine may affect either positively or negatively bumble bees walking and flying activities depending on its concentration, and that GABA enriched solution greatly increase bumble bee survival time. Studies on B. terrestris colony development and reproductive strategies led to define an inbreeding risk index (IRI) for the colony and highlighted the lack of an inbreeding-avoidance system in this species. Finally, three years of rearing practice allowed to provide new guidance methods for diapause and deposition in bumble bee artificial rearing. In conclusion, this thesis may help to better understand of the complex world of plant-pollinator relationships

World Cotton Germplasm Resources

Preservation of plant germplasm resources is vitally important for mankind to supply food and product security in the globalization and technological advances of the 21st century. Mankind preserved a wealth of available genetic resources of many plant species worldwide. One of the such worldwide plant germplasm resources is available for cotton, a unique natural fiber producing cash crop for mankind. Worldwide cotton germplasm collections exist in Australia, Brazil, China, India, France, Pakistan, Turkey, Russia, United States of America, and Uzbekistan. The objective of World Cotton Germplasm Resources book is to present readers with updated information on existing cotton germplasm resources, highlighting detailed inventory, description, storage conditions, characterization and utilization as well as challenges and perspectives. This book should be a comprehensive encyclopedic reading source for plant research community and students to gather important information on worldwide cotton germplasm resources