This research presents the findings of a pollinator diversity study that took place at three study sites. Although variation in pollinator diversity occurred between the three sites, fewer pollinators than expected were recorded from the La Joya Tract (revegetated site). Numerous genera and species were recorded from the Havana Tract (native site) as well as the Valley Nature Center (urban garden). In contrast, the La Joya Tract had a comparatively depauperate pollinator fauna. The numbers of pollinator genera and species recorded from the three study sites were decreased in comparison to the total number of genera and species recorded from Hidalgo County. Hidalgo County has 35 known genera and 75 species of bees documented to date. About 40% of the genera and 23% of the species recorded from Hidalgo County were recorded from the Havana Tract in this study, while a mere 8.5% of the genera and 4% of the species were reported from the La Joya Tract and 34% of the genera and 16% of the species were reported from the Valley Nature Center. Although the vascular plant species identified from these study sites were diverse, the floral rewards they provided yielded an insight as to what was going on in terms of pollinator diversity. Plants may yield nectar or pollen floral rewards or both in some cases to pollinators. The current study provides evidence that revegetation of land with plants that primarily provide nectar rewards will result in fewer observed bee taxa than from land revegetated with plants that provide a mix of nectar and pollen floral rewards.

To date little information has been collected on the pollination biology of <i>Ailanthus altissima</i> (Mill.) Swingle (tree-of-heaven), an invasive exotic in the U.S. This study was conducted to determine the insect pollinator fauna visiting <i>A. altissima</i> and to study general pollinator visitation patterns associated with the tree's nectar profile. A list of taxa visiting trees within each of three sites was developed from collected insects. Overall, visitor assemblage was dominated by the soldier beetle <i>Chauliognathus marginatus</i> with large numbers of ants in the genera <i>Formica</i>, <i>Prenolepis</i>, and <i>Camponotus</i>. No major diurnal pattern was found for visitation of insect pollinators using instantaneous counts. The nectar composition, concentration, and amount of total sugars in the flowers of <i>A. altissima</i> and how these are related to tree gender and time of day were determined. Nectar was found to be sucrose-dominant with lower, but nearly equal amounts of fructose and glucose. Total amounts of sugar in male and female blossoms were not statistically different, however higher concentrations of sugar were found in males (40.7%) than in females (35.3%). No difference was found over time. Nectar production and removal in trees was studied by comparing bagged flowers with flowers open to insect visitation. Bagged flowers were higher in overall sugar than open flowers, however, this was not constant across all times and gender. / Master of Science in Life Sciences

The astonishing diversity of floral form in angiosperm plants is driven in large part by preferences of pollinators for various floral traits, including learned preferences. Remarkably, almost all of a vast literature on learning and memory in pollinators relates to nectar as a reward, even though bees and many flies, beetles, and butterflies must collect pollen. In this study, we asked if bees formed preferences for plant species from which pollen had been collected successfully. Using absolute conditioning, we gave pollen foraging bees experience with plant species that offered only pollen rewards. Naive bees generally showed modest preferences, whereas experienced bees adopted strong preferences for those species over alternative species not previously experienced. Learned preferences were retained for at least 24 h, consistent with preferences learned with nectar rewards. These experience-mediated changes in preference raised the possibility that bees formed associations between particular floral features and pollen rewards. We therefore asked if learned preferences required that bees successfully collect pollen. Using differential conditioning, we determined that learned preferences were strongly influenced by receipt of a pollen reward. In a final experiment, we characterized the importance of 2 floral features, the corolla and the anther, in the expression of learned preferences. Although experience altered responses to both floral parts, responses to anthers were influenced more strongly. We discuss recent evidence in the literature for associative learning with pollen rewards and propose that learned preferences in the context of pollen collection have played an important role in floral display evolution.

Orientador: Anita Jocelyne Marsaioli / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-04T21:09:37Z (GMT). No. of bitstreams: 1 Flach_Adriana_D.pdf: 12925693 bytes, checksum: 5201c81faeca903146104615fff177a3 (MD5) Previous issue date: 2005 / Resumo: O presente trabalho foi dividido em três partes todas relacionadas a química das relações entre os seres vivos. Na primeira parte do trabalho estudou-se a química da polinização de orquídeas da subtribo Maxillariinae em termos da composição dos voláteis e recompensas florais coletadas pelos polinizadores. Discutiu-se também os compostos envolvidos na atração dos polinizadores de Mormolyca ringens e Trigonidium obtusum. Identificou-se, nesta etapa uma série de compostos: hidrocarbonetos, terpenos, álcoois, aldeídos, cetonas, ésteres, etc. Em um segundo momento determinou-se a composição química do néctar de Spathodea campanulata (Bignoniaceae), uma planta relatada como tóxica. Identificou-se, além de carboidratos, compostos secundários como terpenos, esteróides e carboidratos acetilados. Também foram identificados os constituintes voláteis: 1-octen-3-ol e 1-octen-3-ona. Na última parte do trabalho explorou-se a modificação química das ceras de duas espécies de abelhas que estabeleceram uma relação de convivência em um mesmo ninho. A composição química das ceras de operárias de colônias puras e de colônias mistas de M. scutellaris apresentaram perfis químicos diferentes produzindo nas colônias puras uma série de n-alcanos e n-alcenos enquanto que a colônia mista apresentou elevado percentual de acetato de triacontanila. As ceras das colônias de M. rufiventris apresentaram variações nas proporções de hidrocarbonetos. / Abstract: This work is presented in three distincts parts, ali of them concerning the chemistry involved in inter-specific relations. In the first part we discuss the pollination chemistry of orchids, subtribe Maxillariinae, in terms of floral volatiles and rewards collected by polinators. It is also discussed the compounds involved in polinattors attraction by Mormlyca rigens and Trigonidium obtusum. At this stage we have identified hydrocarbons, terpenes, alcohols, aldehydes, ketones, esters, etc. In the second chapter we analyzed the chemical composition of Spathodea campanulata (Bignoniaceae) nectar. Occurence wich has been considered toxic, due to the dead insects inside the flower. Morever, we identified some secondary metabolites as terpenes, steroids and acetylated sugars. Volatiles compounds as 1-octen-3-ol and 1-octen-3-one were also identified. The last part explores the chemical modification in waxes from two bees species that established coexistence in the same nest. We compare the chemical modification of waxes from worker bees in pure and mixed colonies of Meliponia rufiventris and Melipona scutellaris. Revealing that the ratio of alkanes, alkenes, were altered in M. rufiventris colonies. M. scutellaris pure colonie produce alkanes and alkanes and the chemistry of mixed colonies were altered producing high ratio of triacontanyl acetate. / Doutorado / Quimica Organica / Doutor em Ciências

A fundamental question in biology is how animals efficiently locate and use diverse resources. Pollinators foraging on flowers are one of our most thoroughly studied examples of generalist foraging behavior and cognition. Individual pollinators typically specialize on a subset of flowering species available to them. Specialization by nectar-foraging pollinators is often the consequence of learned or innate preferences for floral display traits such as color, pattern, and scent. Pollinators must also typically learn to extract nectar from each floral type. By specializing, pollinators reduce costs associated with learning and forgetting nectar extraction routines. Specialization also benefits the plant by enhancing conspecific pollen transfer. Yet nectar is not the only floral reward. The pollen of hundreds of thousands of plant species is collected by pollinators such as bees, beetles, and flies. In fact, solitary and social bees must collect both pollen and nectar to survive. However, much of the vast literature on bee foraging behavior concerns the collection of nectar. This research investigated mechanisms by which generalist bumblebees (Bombus impatiens) specialize on diverse floral resources. Most foragers in a colony were reward generalists over their lifetime, but specialized daily on either pollen or nectar collection. Lifetime patterns of pollen collection were associated with interindividual differences in sensory morphology. Pollen-foraging bumblebees had weak innate preferences, but learned strong preferences for pollen-only plant species, with preferences mediated primarily by anther properties. The anthers provided indirect cues of concealed pollen, and bees learned to prefer properties of the anthers to select potentially rewarding flowers. While learning was involved in the formation of floral preferences by pollen foragers, pollen extraction behavior relied little on learning. Specifically, floral sonication, which is used by bees to extract concealed pollen, was modified only modestly with experience. Furthermore, bees foraged efficiently for pollen from diverse floral resources without relying on instrumental (associative) learning. Efficient foraging involved switching between two distinct motor routines: floral sonication and scrabbling. Switching was regulated by two ubiquitous floral cues: chemical anther cues eliciting sonication and mechanical pollen cues suppressing it (and eliciting scrabbling). I discuss how mechanisms of floral specialization by generalist pollen-foraging bees could drive floral trait evolution.

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.

Orientador: Anita Jocelyne Marsaioli / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-21T16:16:58Z (GMT). No. of bitstreams: 1 Haleem_MuhammadAbdul_D.pdf: 4864624 bytes, checksum: 45dcc35b401c2d0ab48c1768083d84b1 (MD5) Previous issue date: 2012 / Resumo: O papel dos óleos florais na atração dos polinizadores (abelhas solitárias) é recorrente em várias famílias de angiospermas. Neste estudo foram analisados (CG-EM/IE, ESI-EM, e RMN de 1D de 2D) óleos florais de Malpighiaceae de 33 espécies simpátricas do cerrado pertencentes aos gêneros Banisteriopsis, Byrsonima, Camerea, Heteropterys, Peixotoa, Pterandra, e Tetrapterys e de 48 Krameriaceae. As análises revelaram a presença de ácidos graxos substituídos com cadeias de 18 a 24 átomos de carbono e com dois substituintes, 3,7-diacetoxi, ou 3-hidroxi-7-acetoxi, ou 3,9-diacetoxi, ou 5,7-diacetoxi ou 5,9-diacetoxi. Os ácidos graxos substituídos em 3 e 7 ocorrem predominantemente nos óleos florais de Byrsonima, Heteropterys, Peixotoa reticulate. Os ácidos graxos com dois grupos acetoxi nos carbonos 3 e 9 ocorrem nos óleos florais de Banisteriopsis. Os óleos florais de Peixotoa goina e Tetraptenys jussieuniana são compostos por uma mistura de acilglicerois. A composição química do óleo floral de Pterandra pyroidea é bastante simples e constituída de 4 ácidos graxos sendo que 2 destes apresentaram substituintes nas posições 5 e 7 distinguindo-se dos óleos florais das outras Malpighiaceae. O ácido anti-5,7-diacetoxidocosanóico e o constituinte majoritário deste óleo e sua estrutura foi confirmada por síntese, e caracterizado por espectrometria de massas, RMN de H e C, e finalmente denominado de ácido Pterandrico. Os óleos florais de Krameriaceae possuem também ácido de 18 a 24 átomos de carbono com somente um substituinte acetoxi (-OAc) ou hidroxi (-OH) na posição b. O segundo capítulo da tese se propôs a desvendar a relação entre as recompensas florais (néctar e pólen) do manjericão (Ocimum basilicum) e a provisões encontradas no ninho da abelha solitária Tetrapedia diversipes. Nossas análises revelaram a presença de carboidratos e proteínas nas provisões do ninho de T. diversipes e no pólen de manjericão (O. basilicum). Identificação e caracterização dos constituintes do pólen de Ocimum basilicum e das provisões do ninho de T. diversipes confirmou a presença de glicose, galactose, manose e xilose em ambos. Análises por CG-EM revelaram que galactose e glicose são os constituintes majoritários enquanto que xilose e manose são carboidratos minoritários no pólen e nas provisões do ninho. As semelhanças dos perfis dos carboidratos do pólen de O. basilicum e das provisões dos ninhos de T. diversipes selam a correlação entre esta planta e seu polinizador / Abstract: The role of elaiophores secretion (floral oils) to pollinator attraction (solitary bees) has been established in several angiosperm families. The current study deals with chemical analyses (GC-MS/EI, ESI-MS, and 1D and 2D H and C NMR ¿(HSQC and HMBC) of Malpighiaceae floral oils in 33 sympatric species belonging to Banisteriopsis, Byrsonima, Camerea, Heteropterys, Peixotoa, Pterandra, and Tetrapterys genera and 48 samples of Krameriaceae floral oils. The floral oils spectroscopic data revealed the presence of substituted fatty acids possessing 18 to 24 carbon atoms with two substituents either as 3,7-diacetoxy, or 3-hydroxy-7-acetoxy, or 3,9-diacetoxy, or 5,7-diacetoxy or 5,9-diacetoxy. The 3,7-disubstituted fatty acids are predominant in Byrsonima, Heteropterys, Peixotoa reticulate floral oils, 3,9-diacetoxy disubstituted fatty acids in Banisteriopsis floral oils. While, Peixotoa goina and Tetraptenys jussieuniana elaiophores secretion contain a mixture of acylglycerols. The Pterandra pyroidea floral oil chemical composition is simple, with a few fatty acid constituents possessing acetoxy groups at positions 5 and 7 which is distinct from the rest of floral oil of sympatric Malpighiaceae species. The structure of the major floral oil constituent is a novel fatty acid, anti-5,7-diacetoxydocosanoic acid which was confirmed by synthesis, mass fragmentation, H and C NMR analyses, herein named Pterandric acid. Similarly, Krameriaceae floral oils also contains long chain fatty acids with only one subtituent either acetoxy (-OAc) or hydroxy (-OH) at b position, with 18 to 24 carbon atoms. The second part of thesis deals with the correlation between floral rewards (pollen, nectar) of sweet basil (Ocimum basilicum) and the Tetrapedia diversipes (solitary oil collecting bee) larval nest provisions. Our analyses reveal the presence of carbohydrates and protein in T. diversipes nest provision as well as in the O. basilicum pollen and nectar. Identification and characterization of carbohydrates constituents in the O. basilicum pollen and T. diversipes nest confirmed the presence of glucose, galactose, mannose and xylose in both. Furthermore, mass spectrometric analyses indicated that galactose and glucose are major constituents, while xylose and mannose are minor carbohydrates components present in the O. basilicum pollen and T. diversipes nest provision. The similarity of O.basilicum pollen and T. diversipes nest provision carbonhydrate profiles suggest a plant pollinator correlation / Doutorado / Quimica Organica / Doutor em Ciências

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Em plantas dependentes da polinização biótica, traços florais podem incluir pistas táteis, olfativas e visuais e fatores como cor, formato, odor ou combinações dessas pistas podem ser utilizados para identificar as flores como fonte de recompensas.Um dos componentes que atraem os polinizadores é a simetria, utilizada para discriminação entre flores com diferentes quantidades de recursos e pode ser alterada pela atividade de herbívoros florais, capazes de interferir na quantidade de visitas do polinizador ou alterar a eficiência da polinização. As espécies de Malpighiaceae são conhecidas por ofertar pólen e óleo aos seus visitantes, além de ser uma família importante no Cerrado, um dos ecossistemas que mais sofre degradação no mundo. Diante disso, os objetivos desse estudo foram: a) observar a relação entre simetria floral natural e recursos ofertados aos polinizadores e se b) há discriminação pelos polinizadores entre flores simétricas e flores experimentalmente assimétricas, ou seja, artificialmente danificadas simulando herbivoria e seus efeitos sobre a polinização e consequente produção de frutos. A coleta de dados foi realizada em uma área de cerrado do Clube de Caça e Pesca Itororó de Uberlândia, de setembro de 2013 a julho de 2014. A taxa de simetria floral natural e os recursos florais foram observados nas flores de 24 indivíduos de Byrsonima intermedia (murici-pequeno), das quais 3 inflorescências foram ensacadas na pré-antese e três flores de cada inflorescência tiveram suas medidas tomadas. A partir do eixo longitudinal central da pétala estandarte foram medidas as larguras dos lados direito e esquerdo. Foram medidos os comprimentos das duas pétalas imediatamente ao lado da pétala estandarte (pétalas proximais) pelos seus eixos longitudinais centrais. Foram medidas, ainda, as distâncias do ápice da pétala estandarte até o ápice das duas pétalas mais distantes, ou pétalas distais. Cada flor medida foi também utilizada para a quantificação do volume de óleo de seus elaióforos com tubo capilar e quantificação dos grãos de pólen, retirados e corados com Carmin Acético. Nas mesmas plantas, foram escolhidas quatro flores que tiveram 10% das áreas das pétalas estandarte, proximais ou distais retiradas e quatro controles, que não receberam manipulação. Essas flores foram acompanhadas até a frutificação. Não foram encontradas diferenças significativas entre a quantidade de óleo ofertada aos polinizadores e a simetria floral (r= -0.1407, df= 22, p= 0.5118), bem como para quantidade de pólen (r= -0.0079, df= 22, p= 0.9707), o que indica que, para esse sistema de estudo, a simetria não pode ser utilizada como parâmetro dos recursos disponíveis. Foi encontrada diferença significativa na proporção de frutos formados entre o grupo controle e o grupo tratamento (X²=91,147, gl=3, p<0,01), mas não entre os tratamentos (X²=2,026, gl=2, p=0,363), o que sugere que as manipulações realizadas nas pétalas influenciaram a visitação e consequente polinização, mas o local onde essa manipulação foi realizada não é tão importante. / For plants which rely on biological pollination, floral traits related to pollination can include tactile, olfactory and visual cues and color, shape and odor or combinations of these cues can be used to identify flowers as source of rewards. One of the components that attract pollinators is symmetry, used to discriminate flowers with different levels of rewards. Symmetry can be altered by the activity of floral herbivores, capable of interfering on pollinator visitation rate or alter pollination efficacy. Malpighiaceae species are known to offer pollen and oil to their floral visitors and compose an important family on Brazilian savannah (Cerrado), one of the most degraded ecosystems in the world. The aim of this study was to: a) observe the relation between natural floral symmetry and floral rewards and b) assess pollinator discrimination of experimentally asymmetrical flowers, simulating floral herbivory, and its effects over pollination and fruit set. Data collection was performed in a Cerrado area inside Clube Caca e Pesca Itororo de Uberlandia, from September 2013 to July 2014. Natural floral symmetry and floral rewards were observed in flowers of 24 bushes of Byrsonima intermedia (Malpighiaceae), in which 3 inflorescences were bagged in pre-anthesis phase and three flowers from each inflorescence had their measures taken. The width of right and left sides of the standard petal was measured as well as the length of proximal petals from the central longitudinal axis . The distance of the apex of standard petal to the distal petals was also measured. Each measured flower was then used to the quantification of elaiophores oil volume with a capillary tube and pollen grain quantification, dyed with Acetic Carmin. On the same plants, we chose four plants that had 10% of petal area removed, on standard, proximal or distal petal and four control plants, which were not manipulated. These flowers were followed to fructification and the seeds were placed in gerbox boxes over germination paper. There were no statistical differences between oil quantity and floral symmetry (r= -0.1407, df= 22, p= 0.5118) as well as pollen quantity (r= -0.0079, df= 22, p= 0.9707), which indicates that, for this particular plant, symmetry is not a reliable sign of floral rewards. There was statistical differences in the proportion of fruits formed from control and treatment groups (X²=91,147, gl=3, p<0,01), but not among treatments (X²=2,026, gl=2, p=0,363), what suggests that petal manipulation have an effect on pollinator visitation, but the point of manipulation is not that significant. / Dissertação (Mestrado)