Thesis (Maestro en Ciencias)--Universidad de Puerto Rico, Recinto Universitario de Mayagüez, 2006. / Includes bibliographical references (p. 71-78). Also available in PDF format via the Internet.

Copy number of a copia-like retrotransposon was compared in self- and cross-fertilizing taxa of the annual plant genus, Amsinckia. It was hypothesized that variation in copy number between populations with contrasting mating systems could be used to interpret the relative importance of factors influencing copy number (purging of element-induced mutations, ectopic exchange, and the level of heterozygosity). Populations of Amsinckia spectabilis var. microcarpa and A. furcata, two outcrossing taxa, and their self-fertilizing relatives, A. spectabilis var. spectabilis and A. vernicosa were studied. Probes for Southern hybridisation were generated for each respective taxa through the amplification of a conserved region of the retrotransposon sequence. There were no observable differences in the numbers or patterns of hybridised bands between related self- and cross-fertilizing taxa. The retrotransposon family studied may have been inactive before divergence of Amsinckia taxa, or the factors influencing copy number and genome location may be expressed in such a way as to yield no observable differences in copy number between species with contrasting mating systems.

Inaug.-diss.--Uppsala / "Sonderabdruck aus Uppsala universitets årsskrift, 1925." "Literaturverzeichnis": p. [168]-175.

No description available.

The family Boraginaceae s.l., to which the genus Cordia belongs, comprises some 100 genera and includes ca. 2000 species (Willis, 1973; Cronquist, 1983) with a more or less cosmopolitan distribution. Bentham & Hooker (1876) divided the Boraginaceae in to four tribes based primarily on the characteristics of the style and ovary: (1) Cordieae (style terminal, four-branched with each arm terminating in a clavate or capitate stigma; ovary unlobed); (2) Ehretieae (style terminal or lateral, stigma 4-lobed or bifid); (3) Heliotropieae (style terminal or lateral, stigma 4-lobed, elongate with a subapical depression, ovary unlobed); (4) Borageae (style gynobasic, stigma truncate or capitate, ovary distinctly 4-lobed). Subsequently, these tribes were elevated to the category of subfamily by Gürke (1897, in Engler & Prantl, Die Natürlichen Pflanzenfamilien): (1) Cordioideae, (2) Ehretioideae: (3) Heliotropoideae and (4) Boraginoideae. This treatment of the family Boraginaceae was followed by Rendle (1925), Lawrence (1951) and Cronquist (1983). Hutchinson (1959), combined Cordioideae and Ehretioideae in a distinct (largely woody) family Ehretiaceae with the remaining subfamilies comprising the (largely herbaceous) Boraginaceae s.str. The treatment by Gürke (1897), however, has been more widely accepted, with the genus Cordia aligned with Patagonula and Auxema under the subfamily Cordioideae. The genus Cordia is particularly well represented in the large area of South America delimited by the Federal Republic of Brazil (some 65 species are recognised in the present revision, i.e. ca. one quarter of the total number of species in the whole genus). The treatment of Cordia by Fresenius (1857) for von Martius' Flora Brasiliensis was unfortunate in being based in large part on a rather infelicitous view of the genus by De Candolle (1845) so that although this has been the standard taxonomic work for Cordia in Brazil, it suffers from many deficiencies. Of great value are the taxonomic studies by Johnston (1930-1956) which provided lucid accounts of the infrageneric taxa and species limits (see sect. II for detailed discussion). However, these accounts by Johnston are based on regional areas and extended over a period of 2S years during which this author changed his view of the taxonomy of generic, sectional and specific delimitations. The revision by Johnston (1930) consists the last treatment of the genus for part of Brazil, and thus there is no modern taxonomic account for Cordia for this country. It is this deficiency which the present study attempts to remedy. The present revision is restricted to the Brazilian species of Cordia, but a view of the genus as a whole, in particular the status of infrageneric categories has also been evaluated. Accompanying a formal revision based on external morphology, a palynological study of a number of species of the genus is provided, and also a discussion of the reproductive biology of some species, particularly with regard to the occurrence of heterostyly. The entire genus Cordia presents many interesting aspects such as its diverse morphological features of habit, inflorescence pattern, flowers and fruits; the reproductive biology with heterostyly presumably evolving towards dioecy in many species and perhaps a high level of polyploidy.

Nama L. is a genus of approximately 50 species of herbs and subshrubs that occurs in habitats ranging from arid deserts to mesic woodlands in the New World and the Hawaiian Islands. The group has historically been divided into five or six subgeneric groups based on habitat as well as on the morphology of the anthers, styles, leaves and seeds. At least 14 species of Nama from the Chihuahuan Desert Region are either facultatively or obligately endemic to gypsum deposits. This dissertation examines interspecies relationships within Nama from a molecular phylogenetic perspective in order to evaluate historic morphology-based subgeneric classification systems of the genus and to examine the origins of facultative and obligate gypsophily within the genus. DNA sequence data from the chloroplast regions matK and ndhF and from the nuclear ribosomal region ITS were collected from 46 species of Nama as well as from four new species and several outgroups. Data were analyzed using maximum likelihood and Bayesian methods. Phylogenetic analyses recover seven strongly supported major lineages within Nama. These lineages do not correspond to traditionally recognized subgenera, although they are largely congruent with an informal system based on ultrastructural observations of seeds. Four of the seven major lineages include gypsophilous species; these range from two lineages that include a single facultative gypsophile each, to one lineage that is almost entirely comprised of gypsophiles. Gypsum endemism in general, as well as facultative and obligate gypsophily in particular, has arisen multiple times in Nama. Parametric bootstrapping rejected the hypothetical monophyly of gypsophiles across the genus as a whole and within each of the two clades that contain multiple gypsophiles. Because approximately 20 species have been described since the last major revision of Nama nearly 80 years ago, detailed morphological observations of herbarium specimens were made in order to produce a comprehensive key to the species of Nama as well as the revision of a lineage comprising eight gypsophiles and one limestone endemic. / text

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / O trabalho relata a investigaÃÃo quÃmica dos extratos das raÃzes de Cordia multispicata e Cordia globosa. Para o isolamento dos compostos foram utilizadas tÃcnicas cromatogrÃficas clÃssicas, tais como: cromatografia em coluna aberta e do tipo âflashâ, cromatografia por exclusÃo molecular e cromatografia lÃquida de alta eficiÃncia. A investigaÃÃo quÃmica do extrato hexÃnico de C. multispicata resultou no isolamento de duas naftoquinonas terpÃnicas conhecidas, as cordiaquinonas B e J, alÃm da naftoquinona inÃdita 6-[10-(12,12,16-trimetil-7-oxabiciclo[2.2.1]hept-2-ila]-2,3-dihidroxi-1,4-naftalenodiona, a qual foi denominada de cordiaquinona P. Do extrato etanÃlico das raÃzes de C. globosa foram isoladas duas hidroquinonas terpÃnicas incomuns: (4bE,6Z,8E)-1,4-dihidroxi-9a,10-dihidro-10,12-epoxi-5-etilbenzo[a]azulen-12-ona e (4bZ,6Z,8E)-1-hidroxi-9a,10-dihidro-4,11:10,12-diepoxi-benzo[a]-azulen-11,12-diona, ambas relatadas pela primeira vez. O Ãster N-benzoil-L-fenilalaninato de N-benzoil-2-amino-3-fenilpropila foi tambÃm isolado. A citotoxicidade dos novos compostos foi avaliada frente a trÃs linhagens de cÃlulas tumorais: OVCAR-8 (ovÃrio), SF-295 (glioblastoma) e HCT-116 (cÃlon). Os compostos foram fracamente ativos com valores de IC50 > 5 μg/mL. A determinaÃÃo estrutural das substÃncias isoladas foi realizada atravÃs de mÃtodos espectromÃtricos: IR, EMAR and RMN 1H and 13C, incluindo tÃcnicas bidimensionais (COSY, HSQC, HMBC), alÃm de comparaÃÃo com dados disponÃveis na literatura, sempre que disponÃveis. / This work reports the chemical investigation of the hexane extracts from the roots of Cordia multispicata and Cordia globosa species. For the compounds isolation were used classic chromatographic techniques, such as open and âflashâ chromatography on column over silica gel, molecular exclusion on sephadex LH-20 and High Performance Liquid Cromatography in reverse phase. The chemical investigation of the hexane extract of C. multispicata lead to the isolation of two known terpenoid naphthoquinones, the cordiaquinones B and J. In addition, the new naphthoquinone 6-[10-(12,12,16-trimethyl-7- oxabicyclo[2.2.1]hept-2-yl]-2,3-dihydroxy-1,4-naphthalenedione, which was designed cordiaquinone P. From the hexane extract of C. globosa were isolated two uncommon terpenec hydroquinones, (4bE,6Z,8E)-1,4-dihydroxy-9a,10-dihydro-10,12-epoxy-5- methylbenzo[a]azulen-12-one and 4bZ,6Z,8E)-1-hydroxy-9a,10-dihydro-4,11:10,12- diepoxy-benzo[a]-azulen-11,12-dione, both reported for the first time. The Nbenzoylphenylalaninyl-N-benzoyl-2-amino-3-phenylpropyl was also isolated. The cytotoxic potential of the new compounds were evaluated against three tumor cell lines OVCAR-8 (ovarium), SF-295 (glioblastoma) and HCT-116 (colon). The compounds were weakly active showing IC50 values > 5Âg/mL. The structural elucidation was performed by spectrometric methods: IR, HRMS and 1H and 13C NMR, including bidimensional techniques (COSY, HSQC and HMBC), in addition to comparison with literature data, whenever available.

Doctor of Philosophy / Division of Biology / Carolyn J. Ferguson / The genus Lappula Moench is a diverse group of herbaceous plants in the large, cosmopolitan family Boraginaceae. Over sixty species are recognized in Eurasia; many are found in cold deserts, steppes, and semi-deserts of Central Asia. Fewer species were described from western North America, and compared with the Asian species they are poorly known. Various North American taxa have been placed into synonomy under Eurasian species, and complex patterns of variation have made species circumscription challenging. The goal of this dissertation was to explore phylogenetic relationships between North American and Eurasian species and to revise the taxonomy of the North American species. A molecular phylogenetic study was initiated in order to infer patterns of relationships among the North American species relative to Eurasian diversity. Samples were collected from throughout the western United States and from Siberia. Additional samples of Eurasian species were taken from herbarium specimens. Sequences were generated for three DNA regions (the ITS region of the nuclear ribosomal DNA, and chloroplast intergenic spacers trnS-trnG and rpl32-trnL) and phylogenies were generated using parsimony and Bayesian analyses. Results were in general agreement among all analyses. The genus Lappula was recovered as a monophyletic group, with the exception of the morphologically anomalous L. sessiliflora (Boiss.) Gürke, which was sister to the genus Rochelia Rchb. The native North American species of Lappula and L. redowskii (Hornem.) Greene formed a clade. Samples of L. squarrosa (Retz.) Dumort., a Eurasian steppe plant with a wide introduced range in North America, grouped with samples from Eurasia. Sampled species of Hackelia Opiz, a genus sometimes treated as part of Lappula, formed a clade separate from the Lappula species sampled here. Herbarium and field studies resulted in a revised taxonomy for the North American Lappula. Nomenclatural problems were resolved; nine native species and four varieties were recognized along with the introduced Eurasian species L. squarrosa.

Examining the ecological processes generating evolutionary patterns is crucial to understanding how biodiversity arises and evolves. One of the most striking examples of evolutionary diversification is provided by the flowering plants (angiosperms) and their flowers. Pollinators are traditionally considered to be the most important selective agents and drivers of floral diversity. However, many angiosperms have a generalized floral morphology and are visited by a diverse and overlapping suite of pollinators, making it unclear how pollinators could have driven diversification in these taxa. In addition, flowers and plant reproductive success are likely to be influenced by factors other than pollinators, such as herbivores, precipitation, and temperature. These factors need to be considered along with pollinators in order to improve our understanding of angiosperm evolution and diversification. In my thesis, I focussed on the processes influencing adaptation and diversification in flowering plants in the genus Mertensia (Boraginaceae), which have relatively unspecialized flowers that attract a variety of nectar- and pollen-feeding insects. In Chapter One, I explored correlations among floral traits, vegetative traits, and flowering phenology across 12 Mertensia species. In Chapter Two, I assessed reproductive isolating barriers between related Mertensia species occurring in sympatry. In Chapter Three, I examined the ecological function of floral orientation in two Mertensia species with respect to pollinators and precipitation. First, across Mertensia species, I found that early-flowering species were shorter, produced fewer flowers, and occurred at higher altitudes than late-flowering species—suggesting a life-history trade-off between plant size and flowering phenology, as well as an altitudinal effect on both traits. Interspecific variation in floral traits was not strongly associated with variation in flowering phenology or plant size. Second, between sympatric M. brevistyla and M. fusiformis populations, I found weak reproductive isolating barriers and possible hybridization. Most pre-pollination barriers were weak, as the two Mertensia species shared similar habitats, flowering phenology, and pollinator assemblages. The two relatively strong barriers were floral (ethological and mechanical) isolation and post-pollination isolation: Pollinators transferred significantly more of a pollen analogue among conspecific than heterospecific plants in mixed-species arrays, and flowers yielded higher seed set when receiving conspecific rather than heterospecific pollen in hand-pollination experiments. Lastly, I found that floral orientation was more likely to be under selection by precipitation than by pollinators, in that paternal fitness (i.e., pollen germination) was reduced by contact with water and that pollinator-mediated selection via maternal fitness (i.e., seed set) was not detected. A more pendant floral orientation likely protects the relatively long and exposed anthers of M. fusiformis from rain, while the less pendant M. brevistyla does not require this protection because of its shorter, more concealed reproductive structures. Although I detected an effect of floral orientation on seed set, I was not able to identify the selective agents driving this effect. In summary, my results suggest that pollinators play a minor role in influencing floral adaptation and diversification in Mertensia. Instead, the dominant influences on the traits I examined appear to be life-history trade-offs, environmental conditions that vary along altitudinal gradients, and abiotic variables (e.g., precipitation). It is important to consider these factors and their influences on paternal and maternal fitness in order to gain a broader perspective on floral evolution in plants with generalized pollination systems.

O presente estudo teve como objetivos caracterizar a composição da regeneração natural, da chuva e do banco de sementes presentes sob a copa de três espécies de início de sucessão - Centrolobium tomentosum Guill. ex Benth. (Fabaceae), Cordia myxa L. (Boraginaceae) e Melia azedarach L. (Meliaceae) -, bem como avaliar as possíveis diferenças entre as comunidades que se formaram sob estas espécies. Tal estudo foi desenvolvido em uma área de mata restaurada, localizada no entorno da represa de abastecimento público do município de Iracemápolis (SP). Para tanto, foram marcados 15 indivíduos de cada espécie, sob os quais foram instalados dois coletores de sementes (1 m2 cada), de onde se coletou todos os propágulos depositados por um período de um ano, em coletas mensais. Sob cada um destes 45 indivíduos foi retirada uma amostra de solo (0,5 m x 0,5 m x 0,05 m), que foi posta a pleno sol, por oito semanas, para a avaliação da composição do banco de sementes. A regeneração natural foi avaliada na área de projeção das copas, em uma parcela circular de 2,5 m de raio, na qual se amostraram todos os indivíduos de espécies arbustivo-arbóreas de 0,3 m a 2,0 m de altura. A chuva de sementes sob M. azedarach apresentou-se com maior densidade e sob C. myxa com maior riqueza (p < 0,05). Igualmente, a maior densidade de emergentes do banco de sementes foi observada nas amostras sob M. azedarach e a maior riqueza foi observada sob C. myxa. Quanto à regeneração natural, as comunidades sob as três espécies diferenciaram-se em relação à diversidade de espécies, maior sob os indivíduos de M. azedarach, e à estrutura da comunidade, que se apresentou mais alta sob C. myxa (p < 0,05). A maior parte dos indivíduos e espécies amostradas, tanto na chuva quanto no banco e na regeneração natural, pertencem aos estágios iniciais da sucessão secundária, sendo que muitas, dentre as mais abundantes, são exóticas. As três espécies formam nichos de regeneração, permitindo a germinação e desenvolvimento de plântulas sob elas, influenciando, cada uma, na estrutura e composição das comunidades e contribuindo para a manutenção da diversidade. Por fim, alguns resultados obtidos através deste estudo são importantes para planejamento do monitoramento da área, o qual é fundamental para o emprego de medidas de intervenção, bem como para o entendimento da evolução da floresta que se forma. / The present study describes the composition of natural regeneration, seed rain and seed bank under three early species - Centrolobium tomentosum Guill. ex Benth. (Fabaceae), Cordia myxa L. (Boraginaceae) e Melia azedarach L. (Meliaceae) - and evaluatuation of the possible differences among understory regeneration. The study area, a restored area, is located at the margins of city water reservatory at Iracemápolis (SP). For the study, 15 individuals were selected and under their crown the seed rain was monthly sampled through of the material deposited in 90 1 m x 1 m traps (two by individual). The seed bank was evaluated by 45 soil samples removed from 0,5 m x 0,5 m plots and 5 cm depth, placed under full sun for a period of eight weeks. The natural regeneration was evaluated in circular plots (17 m2), under projection of the crown , where all individuals of timber species, between 0,3 m and 2,0 m tall, were counted and identified. The seed rain under M. azedarach showed higher mean density and under C. myxa higher mean number of species (p < 0,05). Identically, the higher density of seedlings was found in soil samples under M. azedarach and higher number of species under C. myxa. For natural regeneration, the communities showed differences in species diversity, being higher under individuals of M. azedarach, and structure, under individuals of C. myxa was found higher number of seedlings (p < 0,05). The majority of individuals and species sampled is from early secondary succession species, and those species, most of them are exotics. The three species create microsites, allowing the seed germination and growth of seedling under their crowns, acting on community structure and contributing for the maintenance of diversity. Some results obtained in this study are important for projection of monitoring of this restored area, which is fundamental for intervention actions, as well as to the understanding of evolution of the forest under formation.