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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
311

Biologia da reprodução do macho de Viscacha (Lagostomus Maximus) - uma parceria entre Brasil e Argentina para integração da biotecnologia da reprodução em animais ameaçados / Reproductive biology of male viscacha (Lagostomus maximus)-Partnership between Brazil and Argentina for the integration of biotechnology in breeding of endangered animals

Pieri, Naira Caroline Godoy 10 November 2011 (has links)
Atualmente muitos são os estudos com animais silvestres, no entanto, pouco se sabe sobre os aspectos biológicos dos machos. Os Histricomorpha são uma subordem da ordem Rodentia, que representa 43% das 4629 espécies reconhecidas encontradas na classe Mammalia. Os roedores são animais que oferecem uma extraordinária variedade de adaptações ecológicas, suportando os mais diversos tipos de climas e altitudes, podendo com isso apresentar grande diversidade funcional, a viscacha é um roedor pertencente a esta subordem, e de grande importância para o ambiente em que habitam, pois, representam a base da cadeia alimentar. Por esta razão, esta pesquisa ter por objetivo descrever morfologicamente o aparelho reprodutor do macho de viscacha. Foram utilizados seis macho adultos de viscacha, realizou-se análise macro e de microscópia de luz, eletrônica e imunohistoquímicas do sistema reprodutor masculino, bem como a espermatogênese deste animal. Através das análises realizadas, a viscacha apresenta o aparelho reprodutor composto por um par de testículos, epidídimo e ducto deferente e as seguintes glândulas genitais acessórias: próstata, vesícula seminal e glândula bulbouretral. Estas estruturas são semelhantes às de outros roedores já descritos, como a Chinchila e Cutia. A análise espermatogênica demonstrou que esta exibe alterações significativas de seus parâmetros, em sincronia com o ambiente externo e o ciclo reprodutivo. Conclui-se, com os animais estudados, que a morfologia do aparelho reprodutor do L.maximus viscacha é semelhante aos demais roedores pertencentes à subordem dos Histricomorfos. / Many groups are focused their studies on wild animal reproductive biology. However little is still known about the male biology. The Histricomorpha is a suborder of the Rodentia order, which represents 43% of 4,629 recognized species found in the class of Mammalia. Rodents are animals that offer an extraordinary variety of ecological adaptations, supporting all kinds of climates and altitudes, and this may have vast functional diversity. The viscacha is a rodent animal that belongs to this suborder, and it has a great importance to the environment it inhabits, since they represent the base of the food chain. For this reason, this research aims to describe the morphology of the reproductive system of male viscacha. Six adult viscacha males were used for gross anatomy analysis, for light and electron microscopic analysis, and immunhistochemical analysis to describe the normal histology and spermatogenesis of the reproductive tract of adult male viscacha. The reproductive system of the male viscacha consists in a pair of testicles, epididymis and vas deferens and accessory genital glands following: prostate, seminal vesicles and bulbourethral gland. These structures are similar to those already described for other rodents such as Chinchilla and Agouti. The analysis of spermatogenesis suggested that the male viscacha is able to synchronize its spermatogenesis according to the environment, which the animal is inserted in, and its reproductive cycle. This study showed that the reproductive system of the viscacha (L.maximus) is morphologically similar to other rodents belonging to the suborder histricomorphas.
312

In Whose Hands: The Pregnancy Test in American Life

Robinson, Joan Helen January 2018 (has links)
Forty years ago, when an American woman wanted to know if she was pregnant, she made an appointment with a medical professional who would conduct a pregnancy test and tell her the result. Propelled by the medical establishment’s control, surveillance, and neglect of women’s health, the women’s health movement of the 1970s sought to put women’s health “into their own hands.” Encouraged in part by the rhetoric of the women’s health movement, pregnancy tests became available for purchase over-the-counter, without a prescription, and outside of the control of the medical establishment. This dissertation examines this passage of the pregnancy test from the hands of medical professionals to the hands of lay people and asks, has the pregnancy test really delivered on its promise to give women information, choice, and control? We think of women’s reproductive health tools in the hands of doctors as oppressive and in the hands of women as liberating; the central argument of this dissertation is that this view is naïve. Putting the informational power about women’s bodies into a mobile diagnostic technology did not change the nature of the beast. Through this examination of the pregnancy test in American life, we can trace the flow of reproductive power through various people, places, and things to better understand the character of women’s subordination.
313

Cyborg labour : exploring surrogacy as gestational work

Lewis, Sophie January 2017 (has links)
Commercial gestational surrogacy, also called contract pregnancy, involves privately contracting a biogenetically curated pregnancy using IVF. It distinguishes itself from what is commonly considered 'natural' in procreation, in that the human fetuses it produces are formally entered into a legal unit other than the family of the gestator. My work here contends that this practice is best thought, not in isolation, but in the context of social reproduction more generally and as a central component of future geographies of fetal manufacture that would treat (all) pregnancy as work. This project demands, for me, a critical revisiting of theoretic texts like Mary O'Brien's The Politics of Reproduction (O'Brien 1981). But, in my reading, O'Brien's race-blind gynocentrism doomed her to miss the ensemble of practices - forms of surrogacy among them - that have already long been engaged in the sublation of reproductive labour she professes (yet defers until after the revolution). In geography as in O'Brien, the political horizon of reproductive justice theorised by Black and/or Marxist feminists since the 1970s (Davis 1981; Ross et al. 2016), has been neglected. In assembling materials for a future rewriting of "The Politics of Reproduction" in the context of geography -a trans-inclusive uterine geography- I draw on this canon of reproductive justice first. I question the assumption that there can ever be an absence of surrogacy (i.e. an absence of assistance, co-production, or "sym-poesis" (Haraway 2016)) in babymaking. Thus I explore the synthetic substance of surrogacy synthetically, using a lens I call 'gestational labour': a conceptual hybrid of the postwork perspective on care (Weeks 2011; Federici 1975), the Marxist-feminist concept 'clinical labour' (Cooper and Waldby 2014) and cyborgicity (Haraway 1991). Deploying 'gestational labour' together with a commitment to solidarity vis-à-vis surrogates, I analyse recent events, pro- and anti-surrogacy discourses (both clinical-capitalist and activist), and trends in critical literature that illuminate an immanent 'uterine geography' (or fail to). I aim to demonstrate that the technophobic anticommodification critique of surrogacy's detractors is ultimately as insufficient as the class-blind ('philanthrocapitalist') feminism of surrogacy's sales representatives. My point is that so-called natural forms of the family are themselves already 'technologies of reproductive assistance' differently mediated in the market. Our task is unfortunately neither a matter of simply saying 'stop', nor of pretending that the satisfaction people feel in "mutually advantageous exploitation" (Panitch 2013), on such an unequal playing-field, is somehow 'enough'.Surrogate gestators sometimes show us glimpses of 'mothering against motherhood'. They expose gestation as a cyborg form of labour-power, which is to say, collective human activity always already mixed up with 'technologies' on the one hand and strange more-than-human organisms on the other. Pitting surrogacy against surrogacy, I propose keeping our understanding of what surrogacy could mean radically open. On this basis, I point readers and potential future collaborators towards new kinds of sym-poetic geographical practice: surrogacies - or, engagements with reproductive politics in the broadest sense - which I think our historic moment urgently requires.
314

Biologia reprodutiva e qualidade do sêmen de reprodutores de curimbatá, Prochilodus lineatus, em condições distintas de manejo

Souza, Thiago Gonçalves de [UNESP] 30 August 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-30Bitstream added on 2014-06-13T20:48:48Z : No. of bitstreams: 1 souza_tg_me_jabo.pdf: 556522 bytes, checksum: 10d9f685779dd6eaf31aa9ddefd870ec (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A reprodução de peixes migradores nativos apesar de já apresentar relativo sucesso, ainda apresenta diversos obstáculos. Entre eles podemos destacar as variações nas taxas de fertilidade, eclosão e sobrevivência de larvas entre desovas. Desta forma, o objetivo deste trabalho foi avaliar de forma inédita se o manejo pode interferir neste processo em machos de P. lineatus. Os resultados mostraram que os machos mantidos em tanques-rede (TR) com água de baixa qualidade durante 18 meses apresentam encurtamento do ciclo reprodutivo; redução significativa no IGS e no diâmetro de túbulos seminíferos (p<0,05) quando comparados com machos mantidos em viveiros escavados (VE). A concentração espermática e as taxas de fertilidade obtidas com o sêmen dos machos de TR foram inferiores às obtidas com o sêmen dos machos em VE (p<0,05). Além disso, os espermatozoides de TR apresentaram maior frequência de danos de DNA, mesmo apresentando taxas similares de motilidade e sobrevivência que os de VE (p<0,05). Os resultados mostraram de forma inédita que o manejo inadequado pode interferir na gametogênese e na qualidade de gametas masculinos nesta espécie. Além disso, demonstramos que práticas inadequadas de manejo podem prejudicar a função testicular ainda nos meses de inverno, muito antes dos meses de reprodução / The reproduction of native migratory fish still presents several obstacles. Among them we can highlight the changes in fertility rates, hatching and survival of larvae among spawning. Thus, the objective of this study was to evaluate in an unprecedented way if the reproductive management can interfere in this process in males of P. lineatus. The results showed that males kept in cages (C) for 18 months have their reproductive cycle shortened; significant reduction in the GSI and in the diameter of seminiferous tubules (p<0.05) compared with males kept in earths ponds (EP). The sperm concentration and fertility rates obtained with semen from males of Cs were lower than those obtained with semen EP (p<0.05). In addition, the sperm of males maintained in Cs had higher frequency of DNA damage, even with similar rates of survival and motility of the EPs (p<0.05). The results showed by unprecedented manner that the improper management can interfere with gametogenesis and quality of male gametes in this species. Furthermore, we demonstrate inadequate management practices can affect the testicular development even in the winter months, long before the breeding season
315

The Role of Nonapeptides in Male Reproduction in Two Cyprinid Species, the Zebrafish (Danio rerio) and the Goldfish (Carassius auratus)

Altmieme, Zeinab 19 March 2019 (has links)
Two distinct nonapeptide systems, consisting of the vasotocin- and oxytocin-related peptides have evolved in vertebrates, and their role in male reproduction is well-described in mammals. In contrast, their comparative role in reproduction in basal vertebrate species, and teleost fishes in particular, has not been investigated in great detail. Using two cyprinid species, the zebrafish (D. rerio) and the goldfish (C. auratus), I address the hypothesis that the teleost nonapeptides vasotocin and isotocin stimulate male cyprinid reproductive physiology by affecting central neuronal and/or peripheral endocrine pathways. To test this hypothesis in zebrafish, an indeterminate breeder, I conducted pharmacological inhibition experiments employing vasotocin and isotocin-specific antagonists in males, a treatment predicted to inhibit reproductive success in mating trials. Because nonapeptides can act both as central peptide neuromodulators and as secreted hormone, I further quantified indices of male courtship behavior (nudging, circling and chasing) and major androgens (testosterone and 11-keto-testosterone) as key endocrine indices of the male reproductive axis. Together, these experiments revealed a dose-dependent, differential inhibition of spawning success, with significant reductions (-65%) in egg fertilization rate observed in pairs in which males had been i.p. injected with 5 ng/g vasotocin and significant reductions (-79%) observed at 500 ng/g i.p injected isotocin. In either case, these partial inhibitions of reproductive success were correlated with significant decreases in specific indices of male courtship behavior, but not endocrine indices, suggesting that individual nonapeptides mediate their effects via central modulation of behavioural neurocircuits. Interestingly, a co-administration of vasotocin and isotocin antagonists completely abolished reproductive success, however this effect was neither correlated with decreases in male courtship behavior, nor endocrine indices, suggesting a separate mode of action, possibly at the level of male pheromone release. To further probe the role of nonapeptides in male zebrafish reproduction, I subsequently tested the hypothesis that nonapeptide systems are acutely activated by key reproductive cues, specifically the releaser pheromone PGF2α, which serves as a chemoattractant and acutely stimulates male reproductive behavior in male cyprinids. Using a chemoattractant choice assay in conjunction with immunohistochemistry and gene expression approaches, I determined whether male zebrafish are attracted to pheromonal cues and acutely activate isotocinergic neurons in the short term and/or regulate nonapeptide gene expression in the longer term. My results show that individual male zebrafish are attracted to PGF2α in an acute choice test. Furthermore, an increase in p-ERK immunoreactivity, a marker of neuronal activation, was observed in the olfactory bulb 10 min following exposure, suggesting a specific response to the pheromone compared to EtOH vehicle. However, no co-localization of p-ERK and IT-positive perikarya was observed in the preoptic area (POA), refuting the hypothesis that PGF2α exposure acutely activates isotocinergic neurons in zebrafish. Analysis of whole brain relative mRNA transcript abundance revealed that PGF2α exposure time-dependently regulates whole brain isotocin, but not vasotocin transcript abundance, suggesting secondary longer-term effects of PGF2α exposure on the isotocinergic system. Using an analogous experimental approach, I further tested the hypothesis that nonapeptides stimulate male reproductive physiology in goldfish, a determinate breeder. Sexually mature male goldfish pretreated with saline or vasotocin or isotocin antagonists were exposed to saline or PGF2α-injected stimulus females and male courtship behavior (chasing, circling), endocrine indices (circulating testosterone) and milt release were quantified. Both nonapeptide antagonists reduced strippable male milt quantity in response to PGF2α-injected females, suggesting a neuronal or hormonal action of both nonapeptides on goldfish milt release. Together, I show that nonapeptides contribute to male reproductive physiology in two species of cyprinids with different reproductive tactics. However, the mode of action may differ from one species to another, with evidence suggesting that nonapeptides play a role in the regulation of reproductive behavior and, possibly, male pheromone, release in zebrafish, while effects on male goldfish seem to be exclusively related to the release of milt. Future studies should compare other teleost species with specific reproductive biology and focus on the gonadal roles of nonapeptides in sperm maturation and/or release.
316

Fenologia reprodutiva de espécies florestais nativas com potencial oleaginoso na Amazônia Central

Pinto, Antonio Moçambite [UNESP] 02 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-02Bitstream added on 2014-06-13T21:01:43Z : No. of bitstreams: 1 pinto_am_dr_rcla.pdf: 291102 bytes, checksum: fd37e45ac3f35881070a810a19d57f4a (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Esta pesquisa teve como objetivo gerar informações básicas sobre a silvicultura das espécies florestais para possibilitar a implementação de programas de reflorestamento e recuperação de áreas degradadas na região amazônica. Trata-se de um estudo fenológico realizado pelo INPA, Manaus, Amazonas, especificamente pela Coordenação de Pesquisas em Silvicultura Tropical, ao longo de 35 anos. Este estudo analisou duas áreas de floresta amazônica, a Reserva Florestal Ducke (RFD) e a Estação Experimental de Silvicultura Tropical (EEST), no período de 1974 a 2000. O objetivo específico foi comparar os padrões fenológicos nas duas áreas experimentais, verificando sua regularidade e relação com fatores climáticos. As espécies selecionadas foram aquelas indicadas com potencial oleaginoso e ecológico, em avaliações preliminares e que estão sendo observadas para o estudo, a saber: Andiroba - Carapa guianensis Aubl.; Cumaru - Dipteryx odorata (Aubl.) Willd.; Casca preciosa - Aniba canelilla (H.B.K.) Mez e Pau rosa - Aniba rosaeodora Ducke. Foram amostrados 21 indivíduos de A. rosaeodora Ducke na RFD e cinco na EEST, e cinco indivíduos das espécies restantes em cada uma das duas áreas de estudo. Observados mensalmente com auxílio de um binóculo para o registro das fenofases (botões florais, antese, frutos imaturos e maduros). Os padrões fenológicos reprodutivos foram descritos de acordo com sua freqüência... . / This research aims to generate basic information about the silviculture of forest species to make the implementation of reforestation programs and the recovering of degraded areas in the Amazon region possible. This phenological research has been conducted by INPA, specifically by the Tropical Silviculture Research Coordination, over a period of 35 years. This study will analyze two areas in the Amazon Forest, Reserva Florestal Ducke (RFD) and Estação Experimental de Silvicultura Tropical (EEST), in the period between 1974 and 2000. The specific objective is to compare the phenological patterns in both experimental areas, verifying their regularity and relationship with climatic factors. The species selected were those indicated with oily and ecological potential in preliminary evaluations: Andiroba - Carapa guianensis Aubl; Cumaru - Dipteryx odorata (Aubl) Willd; Casca preciosa - Aniba canelilla (H.B.K.) Mez and Pau rosa - Aniba rosaeodora Ducke. It were sampled twentyone individuals of A. rosaeodora Ducke in RFD and five in EEST, and five individuals of the remaining species in each one of the two areas of study. The individuals were monthly observed with the assistance of binoculars to record the phenophases. The phenological patterns will be described with regards to their frequency, regularity and duration. The relations among the phenological data with the climatic variables were made through the non-parametric Spearman linear correlation analyses taking in consideration the climatic monthly mean values. It was observed at EEST, that the flowering of the species studied tend to occur in a period of less precipitation, except for Carapa guianensis that tended to bloom in the transition from dry season to rainy season. Whereas, for Aniba rosaeodora the flowering tended to occur in the rainy epoch and... (Complete abstract, click electronic address below).
317

Quantitative genetic and genomic analyses of the effect of Porcine Reproductive and Respiratory Syndrome (PRRS) outbreaks on the reproductive performance of sows

Orrett, Christopher Mark January 2018 (has links)
Porcine Reproductive and Respiratory Syndrome (PRRS) is, globally, one of the costliest of diseases to the pig industry. Despite enormous efforts, methods such as vaccination strategies and herd management have failed to fully control the disease. Exploiting the genetic variation in host response could be included as part of a multifaceted approach to mitigate the devastating impact of this disease. Establishing the presence of genetic variation and its underlying genetic architecture are key to implementing genomic selection, which is considered a viable and safe long-term disease control strategy. This thesis explores the effect of natural PRRSV outbreaks on the reproductive performance of sows, and the underlying genetic influences on it. Litter records were available from two farms, where Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) outbreaks had been confirmed using ELISA. One farm had full pedigree information, but for both farms 60K SNP genotypes were available. In both farms, performance records could be partitioned into an epidemic and non-epidemic phase using a previously established threshold method. The partitioning also identified a period of high reproductive failure not coinciding with a diagnosed PRRSV outbreak on one farm. This period was isolated and analysed separately. Linear mixed models were used to explore both genetic and non-genetic factors contributing to differences in reproductive performance associated with the two phases. This analysis identified five disease indicator traits identified showing significant differences (>95% CI) in least squares means between the epidemic and non-epidemic phase. These were the number of mummified, stillborn, dead and alive piglets per litter and the fraction of the total born dead. Alternative statistical models that accounted for differences in the severity of the individual PRRSV outbreaks were also considered throughout. Despite differences in the estimates associated with different models and farms, in general very low heritability estimates were obtained for these disease indicator traits during the non-epidemic phase, whereas the traits were found moderately heritable during the epidemic phase. Two genome wide association analyses methods were used to explore the distribution of the genetic effects throughout the genome: Family-based Score Test for Association (FASTA) and Genome-wide Rapid Analysis using Mixed Model and Regression (GRAMMAR). In addition, regional associations were studied using Regional Heritability Mapping (RHM). Associations were then further characterised using Measured Genotype (MG) analyses. Genome-wide significant associations were identified for five SNPs and one region. The regional association spans the region previously identified in an experimental challenge experiment of growing pigs, in association with viral load and weight gain. Different patterns of linkage disequilibrium (LD) are observed which may explain why this study and others failed to find single SNP effects at this location. One genome wide significant SNP on SSC15 was found between two previously identified SNPs associated with PRRSV mortality. Five further putative SNP associations are indicated by RHM and subsequent measured genotype analysis, two of which flank previously reported associations and indicate an epistatic effect, observed in several traits. In summary, this study showed that reproductive performance of sow is considerably reduced during PRRSV outbreaks and the genetics of the sow significantly affects variance in survival and mortality. Several novel genomic regions associated with the reproductive performance of sows in the absence and during PRRSV outbreaks have been identified in this study. In addition to these, the results suggest the region on SSC4 previously associated with PRRSV viral load and weight gain may also affect foetal mortality. These results demonstrate the potential for genomic selection to be used to mitigate PRRSV related reproductive losses, the greatest financial exposure faced by the pig industry. In addition, RHM is directly shown to capture genetic variance, where single SNP methods fail to identify an effect, highlighting the usefulness of this tool as a method to identify genomic regions with significant effect on production traits.
318

Mammalian Community Recovery from Volcanic Eruptions in the Cenozoic of North America

Famoso, Nicholas 27 September 2017 (has links)
It is clear that ecosystems are devastated after a volcanic eruption coats the landscape with a layer of ash; however, the ecological recovery of mammalian communities after eruptions is poorly understood. Volcanic eruptions vary with magnitude and type and only a fraction of them have been analyzed for effects on mammalian communities. To better understand mammalian community recovery, I investigated three different lines of evidence. First, I created a new numeric metric for statistically analyzing reproductive strategies in mammals and tested the impact of diet and body size on reproductive strategies within a phylogenetic framework as proof of concept. The trend of lower reproductive rates and larger body size hold true for herbivores and omnivores, but different trajectories exist for carnivores. Second, I investigated how species richness, evenness, and similarity change across volcanic boundaries in the 1980 Mount St. Helens (MSH), Washington, and 1914-1917 Mount Lassen, California, eruptions. Richness and evenness remain unchanged in Lassen. MSH saw an immediate drop in richness followed by an increase over five years to pre-eruptive levels. Chord distance analysis suggests no long-term change in the Lassen fauna. The pre- and post-MSH fauna are different from one another. The post-eruptive fauna was more similar to neighboring regions. Lastly, I tested whether the Oligocene horse Miohippus demonstrated morphological changes across the volcanic Picture Gorge ignimbrite (PGI; 29.069 Ma) in the John Day Formation of Oregon. Variation in upper and lower teeth was first tested to define a single species in the assemblage. Length, width, and wear of teeth were compared across the PGI and there were no significant differences between pre- and post-PGI assemblages. It is clear from my results that larger eruptions tend to have a greater impact on mammalian community recovery than smaller eruptions, but ultimately, mammalian populations are robust and the presence of neighboring communities is important for recolonizing devastated areas. There are two supplemental files associated with this dissertation, a CSV file of raw data downloaded for Chapter III and an excel file of raw data and coefficient of variation calculations for Chapter IV. This dissertation includes both unpublished and co-authored material.
319

Anastrozole when used as a superovulator, may alter key focal adhesion proteins associated with receptivity of uterine epithelial cells during implantation in the rat: a potential therapeutic clue in assisted reproductive technologies

Mwakikunga, Anthony Raphael. January 2015 (has links)
A thesis submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Doctor of Philosophy July, 2015 / Introduction: Anastrozole is clinically effective in ovulation induction, but it has not been well researched. The aim of this study was to determine the optimal dose for anastrozole as a superovulator and ascertain its effects on implantation in Wistar rats; also to determine its effects on uterine morphology during early pregnancy using light microscopy and scanning electron microscopy (SEM). [Abbreviated Abstract. Open document to view full version] / AC2016
320

Biologia reprodutiva de cana-de-açúcar (Saccharum x officinarum) e de um parente selvagem (S. villosum Steud) com potencial de contaminação por pólen / Reproductive biology of sugarcane (Saccharum x officinarum) and a wild relative (S. villosum Steud) with pollen contamination potential

Toledo, Jayça Amate Marim 15 July 2015 (has links)
A cana-de-açúcar atualmente encontra-se em posição de destaque como terceira maior cultivar em área plantada no Brasil. Porém, a cultura ainda não se beneficia de tecnologias de engenharia genética no mercado brasileiro. A razão disso, está diretamente relacionada às normativas de liberação da CTNBio (RN05), a qual requer informações relevantes acerca da capacidade dispersiva de estruturas reprodutivas de organismos geneticamente modificados (OGMs) e seus mecanismos de dispersão. A fim de não comprometer o curso natural da evolução do gênero Saccharum, em que pertence a Cana-de-açúcar, a CTNBio querer também informações à cerca de seus parentes silvestres como sua área de ocorrência e seus mecanismos reprodutivos de dispersão com o objetivo de eliminar o risco de hibridação introgressão com os OGMs. Através de estudos prévios, sabe-se que a cana-de-açúcar é altamente cultivada na região nordeste e centro-sul do Brasil e que as espécies pertencentes ao gênero Saccharum selvagens como S. asperum (Nees) Steud. e S. villosum Steud. são encontradas na região Centro-Sul. Pensando nisso, a espécie S. villosum chama a atenção pelo fato ocorrer próximo à áreas de plantio de cana-de-açúcar, onde haveria risco da contaminação de transgenes. O objetivo do trabalho buscou trazer informações do ciclo reprodutivo da espécie S. villosum em comparação ao comportamento reprodutivo de cana-de-açúcar na região Centro-Sul do Brasil. Também buscou-se adquirir informações relevantes sobre a morfologia e a viabilidade dos grãos de pólen da espécie e de vários híbridos da cana-de-açúcar que ocorrem na região em questão. Assim como, informações sobre a morfologia pós-seminal da espécies S. villosum, com o objetivo de auxiliar na taxonomia do grupo. Nos estudos sobre o ciclo de vida da espécie S. villosum, foram encontrados florescimento de Abril à Julho com comportamento alógamo e de Setembro à Março com comportamento autógamo. Esses resultados auxiliam estudos de fluxo gênico entre híbridos de cana-de-açúcar e S. villosum em determinadas épocas do ano. Além disso, as características morfológicas dos grãos de pólen de S. villosum correspondem às do gênero Saccharum. As características reprodutivas dos híbridos de cana-de-açúcar na região Centro-Sul do Brasil possibilita o fluxo gênico interespecífico, por conterem grãos de pólen viáveis e formação de sementes. A sincronia do florescimento entre as espécies estudadas mostrou-se correspondentes. As características morfológicas no momento da germinação das sementes de S. villosum apresentou-se correspondentes aos integrantes do complexo Saccharum como o gênero Erianthus, esses dados irão auxiliar trabalhos futuros no reconhecimento taxonômico à nível genérico e específico. Portanto, a espécie S. villosum apresenta características reprodutivas viáveis, os quais podem resultar em cruzamento interespecífico com híbridos de cana-de-açúcar. Esses resultados irão auxiliar futuros estudos de fluxo gênico entre as espécies analisadas. / The sugarcane currently is in a prominent position as the third largest growing in planted area in Brazil. However, the culture still does not benefit from genetic engineering technologies in Brazil. The reason is directly related to the regulatory release of CTNBio (RN05), which requires relevant information about the dispersive ability of reproductive structures of genetically modified organisms (GMOs) and their dispersal mechanisms. In order not to compromise the natural course of evolution of the genus Saccharum, which belongs to sugarcane, CTNBio also want the information about their wild relatives as its range and their reproductive mechanisms of dispersion in order to eliminate the risk of hybridization introgression with GMOs. Through previous studies, it is known that sugarcane is highly cultivated in the northeast and South-Central Brazil and the wild species of the genus Saccharum as S. asperum (Nees) Steud. and S. villosum Steud. are found in the South-Central region. Thinking about it, S. villosum species draws attention because occur near areas of sugarcane plantation where there is risk of transgene contamination. The objective sought to bring information of the reproductive cycle of the species S. villosum compared to reproductive behavior of sugarcane in the South-Central region of Brazil. Also sought to acquire relevant information about the morphology and viability of pollen grains of the species and various hybrids of sugarcane that occur in the region in question. As well as information on post-seminal morphology of the species S. villosum, in order to assist the group\'s taxonomy. In studies on the life cycle of the species S. villosum, they were found flowering April to July with allogamous behavior and from September to March with autogamous behavior. These results help studies of gene flow between hybrid sugarcane and S. villosum at certain times of year. Furthermore, the morphological characteristics of the pollen grains S. villosum correspond to the genus Saccharum. The reproductive characteristics of sugarcane hybrids in South-Central region of Brazil enables interspecific gene flow, to contain viable pollen grains and seed formation. The timing of flowering among the species studied showed up correspondents. The morphological characteristics at the time of germination of S. villosum has performed corresponding to the Saccharum complex members as Erianthus, this data will assist future work on taxonomic recognition of the generic and specific level. Therefore, the species S. villosum shows viable reproductive characteristics, which may result in interspecific cross with sugarcane hybrids. These results will help future studies of gene flow between species analyzed.

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