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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.
1

The effects of shoot orientation, sadh, ethephon and scoring on growth, flower bud formation and development of young apple trees /

Hamzakheyl, Noorgul January 1975 (has links)
No description available.
2

Insetos predadores de sementes e suas relações com a qualidade e a morfologia de frutos e sementes

Rodrigues, Ligia Maria da Silva [UNESP] 24 January 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-01-24Bitstream added on 2014-06-13T19:43:48Z : No. of bitstreams: 1 000738102.pdf: 3260971 bytes, checksum: a1247f6fe649b23fdfe36cebbab2c317 (MD5) / Este estudo teve como objetivos conhecer a comunidade de insetos consumidores de sementes na fase de pré-dispersão e suas plantas hospedeiras em áreas de floresta estacional semidecidual, quantificar os níveis de danos causados por estes insetos, e também verificar se caracteres qualitativos (compostos fenólicos, proteína total e dureza das sementes) e morfológicos (forma e biomassa) das sementes interferem no tamanho corporal das principais ordens de insetos encontradas predando as sementes e nas taxas de emergência destes insetos. Em áreas da Fazenda Experimental Edgárdia, foram selecionadas 89 plantas de 30 espécies, pertencentes a seis famílias. Foram realizadas coletas mensais de frutos e acompanhamento da fenologia reprodutiva por dois anos. Após as coletas os frutos foram armazenados para aguardar a emergência dos insetos e após emergência, os insetos, frutos e sementes foram medidos. As sementes também foram testadas para determinar sua dureza e foram analisadas quanto à biomassa, teor de água, nitrogênio total e compostos fenólicos totais. Houve emergência de insetos provenientes de três ordens, Coleoptera, Lepidoptera e Hymenoptera em 21 espécies de plantas. Coleoptera foi a que apresentou maior número de indivíduos emergindo dos frutos, seguida por Hymenoptera e por último Lepidoptera. Nos coleópteros foram observadas cinco famílias predando as sementes, Anobiidae, Anthribidae, Cerambycidae, Curculionidae e Chrysomelidae. A subfamília Bruchinae (Chrysomelidae) foi a que teve o maior número de insetos emergindo dos frutos de 14 espécies de plantas, com o total de sete gêneros identificados. Hymenaea courbaril foi a espécie mais intensamente predada (53,99%) e o maior consumo se deu por insetos da ordem Lepidoptera (35,14%). Já a espécie Luehea divaricata apresentou a menor taxa de predação (0,07%). A qualidade das sementes exerceu influência significativa apenas no que diz... / This study aimed to identify the insect community of pre-dispersal seed consumers and their host plants in semi-deciduous forest areas, quantify the levels of damage caused by these insects in their seeds, exam whether qualitative characters (phenolic compounds, total protein and hardness of seeds) and morphological characters (form and biomass) of seeds interfere with body size and rates of emergency of the main insect pre-dispersal seed predators orders feeding on these seeds. 89 plants of 30 species belonging to six families were selected in five areas at the Experimental Farm Edgárdia. Fruit collections and reproductive phenology monitoring were made every month during two years. After collection, fruits were stored to await the emergence of insects and after emergence, the insects, fruits and seeds were measured. Then the hardness, biomass and water content, total nitrogen and total phenolics were estimated in seeds. Insects emerged from 21 plant species and from three orders: Coleoptera, Lepidoptera and Hymenoptera. Coleoptera showed the highest number of individuals emerging from fruits, followed by Hymenoptera and Lepidoptera, respectively. Coleoptera showed five families preying on seeds, Anobiidae, Anthribidae, Cerambycidae, Curculionidae and Chrysomelidae. The subfamily Bruchinae (Chrysomelidae) was the one with the greatest number of insects emerging from the fruits of 14 plant species, with a total of seven genera identified. Hymenaea courbaril was the most heavily predated plant (53.99%) and the highest consumption occurred by insects of the order Lepidoptera (35.14%); on the other hand Luehea divaricata showed the lowest predation rate (0.07%). Seed quality had significant effect only in relation to body size of beetles and butterflies, since larger insects were observed in tougher seeds. For the morphological data and biomass of seeds was observed that the species with higher biomass ...
3

Caracterização da variabilidade morfoagronômica de maracujazeiro (Passiflora cincinnata Mast.) no semi-árido brasileiro

Araújo, Francisco Pinheiro de [UNESP] 17 July 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-07-17Bitstream added on 2014-06-13T21:04:20Z : No. of bitstreams: 1 araujo_fp_dr_botfca.pdf: 860426 bytes, checksum: e6646af0ab59a2403e60928f75194d0c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho foi desenvolvido com a finalidade de avaliar a variabilidade morfoagronômica de Passiflora cincinnata Mast., distribuída em diferentes regiões agroecológicas do Nordeste brasileiro. Foram utilizadas 32 características obtidas em experimento conduzido na Embrapa Semi-Árido, em Petrolina-PE, em delineamento de blocos ao acaso com quatro repetições. O desempenho dos acessos foi avaliado pela análise univariada e os estudos relativos à divergência genética foram realizados com base nos procedimentos multivariados, utilizando-se a distância generalizada de Mahalanobis (D2) e a técnica de agrupamento por variáveis canônicas. A dispersão gráfica dos acessos teve como eixos as primeiras variáveis canônicas. A estratégia de coleta de acessos de P. cincinnata mostrou-se efetiva porque os acessos coletados apresentaram variabilidade genética para todos os descritores utilizados na avaliação. Os caracteres mais importantes para discriminação entre acessos foram: diâmetro das hastes (DH), número de glândulas foliares (NGF), número de glândulas por bráctea (NGB), viabilidade de pólen (VP), massa do fruto (PF), massa da semente (MS) e massa total de frutos (MTF). Contudo, por serem caracteres influenciados pelo ambiente, os acessos devem ser avaliados em mais de um ambiente. O agrupamento dos acessos com base em suas variabilidades genéticas não foi correlacionado com sua origem geográfica. Foram obtidos acessos que, pela alta produtividade de frutos, podem ser recomendados para cultivos experimentais em áreas de produtores. / The present work was developed aiming at evaluating the morphoagronomic variability of Passiflora cincinnata Mast., which is distributed in different agroecological regions in Northeast Brazil. Data from 32 characters were used in experiments, carried out at Embrapa Tropical Semi-Arid, Petrolina-PE, Brazil, in a randomized complete block design with four replications. The behaviour of accesses was evaluated by univariate analysis and the studies related to the genetic diversity were done based on the multivariate procedures, using the general distance of Mahalanobis (Dø) and the grouping technique by canonic variables. The graphic dispersion of the accesses used the first canonic variables as axis. The strategies for collecting the accesses of P. cincinnata proved to be effective because the collected accesses showed genetic variability for all the descriptors used in the evaluation. The most important characters for the discrimination among accesses were: stem diameter (SD), number of leaf glands (NLG), number of glands per bract (NGB), pollen viability (PV), fruit mass (FM), seed mass (SM) and total fruit mass (TFM). However, as the environment influences the characters, the accesses must be evaluated in more than one environment. Grouping of accesses based on their genetic variability was not correlated with their geographic origin. Since some accesses showed high fruit productivity, they can be recommended to farmers for experimental growing.
4

Insetos predadores de sementes e suas relações com a qualidade e a morfologia de frutos e sementes /

Rodrigues, Ligia Maria da Silva. January 2013 (has links)
Orientador: Marcelo Nogueira Rossi / Banca: Wesley Augusto Conde Godoy / Banca: Renata Cristina Batista Fonseca / Banca: Edson Luiz lopes Baldin / Banca: Claudio José Von Rossi / Resumo: Este estudo teve como objetivos conhecer a comunidade de insetos consumidores de sementes na fase de pré-dispersão e suas plantas hospedeiras em áreas de floresta estacional semidecidual, quantificar os níveis de danos causados por estes insetos, e também verificar se caracteres qualitativos (compostos fenólicos, proteína total e dureza das sementes) e morfológicos (forma e biomassa) das sementes interferem no tamanho corporal das principais ordens de insetos encontradas predando as sementes e nas taxas de emergência destes insetos. Em áreas da Fazenda Experimental Edgárdia, foram selecionadas 89 plantas de 30 espécies, pertencentes a seis famílias. Foram realizadas coletas mensais de frutos e acompanhamento da fenologia reprodutiva por dois anos. Após as coletas os frutos foram armazenados para aguardar a emergência dos insetos e após emergência, os insetos, frutos e sementes foram medidos. As sementes também foram testadas para determinar sua dureza e foram analisadas quanto à biomassa, teor de água, nitrogênio total e compostos fenólicos totais. Houve emergência de insetos provenientes de três ordens, Coleoptera, Lepidoptera e Hymenoptera em 21 espécies de plantas. Coleoptera foi a que apresentou maior número de indivíduos emergindo dos frutos, seguida por Hymenoptera e por último Lepidoptera. Nos coleópteros foram observadas cinco famílias predando as sementes, Anobiidae, Anthribidae, Cerambycidae, Curculionidae e Chrysomelidae. A subfamília Bruchinae (Chrysomelidae) foi a que teve o maior número de insetos emergindo dos frutos de 14 espécies de plantas, com o total de sete gêneros identificados. Hymenaea courbaril foi a espécie mais intensamente predada (53,99%) e o maior consumo se deu por insetos da ordem Lepidoptera (35,14%). Já a espécie Luehea divaricata apresentou a menor taxa de predação (0,07%). A qualidade das sementes exerceu influência significativa apenas no que diz ... / Abstract: This study aimed to identify the insect community of pre-dispersal seed consumers and their host plants in semi-deciduous forest areas, quantify the levels of damage caused by these insects in their seeds, exam whether qualitative characters (phenolic compounds, total protein and hardness of seeds) and morphological characters (form and biomass) of seeds interfere with body size and rates of emergency of the main insect pre-dispersal seed predators orders feeding on these seeds. 89 plants of 30 species belonging to six families were selected in five areas at the Experimental Farm Edgárdia. Fruit collections and reproductive phenology monitoring were made every month during two years. After collection, fruits were stored to await the emergence of insects and after emergence, the insects, fruits and seeds were measured. Then the hardness, biomass and water content, total nitrogen and total phenolics were estimated in seeds. Insects emerged from 21 plant species and from three orders: Coleoptera, Lepidoptera and Hymenoptera. Coleoptera showed the highest number of individuals emerging from fruits, followed by Hymenoptera and Lepidoptera, respectively. Coleoptera showed five families preying on seeds, Anobiidae, Anthribidae, Cerambycidae, Curculionidae and Chrysomelidae. The subfamily Bruchinae (Chrysomelidae) was the one with the greatest number of insects emerging from the fruits of 14 plant species, with a total of seven genera identified. Hymenaea courbaril was the most heavily predated plant (53.99%) and the highest consumption occurred by insects of the order Lepidoptera (35.14%); on the other hand Luehea divaricata showed the lowest predation rate (0.07%). Seed quality had significant effect only in relation to body size of beetles and butterflies, since larger insects were observed in tougher seeds. For the morphological data and biomass of seeds was observed that the species with higher biomass ... / Doutor
5

Caracterização da variabilidade morfoagronômica de maracujazeiro (Passiflora cincinnata Mast.) no semi-árido brasileiro /

Araújo, Francisco Pinheiro de, 1957- January 2007 (has links)
Resumo: O presente trabalho foi desenvolvido com a finalidade de avaliar a variabilidade morfoagronômica de Passiflora cincinnata Mast., distribuída em diferentes regiões agroecológicas do Nordeste brasileiro. Foram utilizadas 32 características obtidas em experimento conduzido na Embrapa Semi-Árido, em Petrolina-PE, em delineamento de blocos ao acaso com quatro repetições. O desempenho dos acessos foi avaliado pela análise univariada e os estudos relativos à divergência genética foram realizados com base nos procedimentos multivariados, utilizando-se a distância generalizada de Mahalanobis (D2) e a técnica de agrupamento por variáveis canônicas. A dispersão gráfica dos acessos teve como eixos as primeiras variáveis canônicas. A estratégia de coleta de acessos de P. cincinnata mostrou-se efetiva porque os acessos coletados apresentaram variabilidade genética para todos os descritores utilizados na avaliação. Os caracteres mais importantes para discriminação entre acessos foram: diâmetro das hastes (DH), número de glândulas foliares (NGF), número de glândulas por bráctea (NGB), viabilidade de pólen (VP), massa do fruto (PF), massa da semente (MS) e massa total de frutos (MTF). Contudo, por serem caracteres influenciados pelo ambiente, os acessos devem ser avaliados em mais de um ambiente. O agrupamento dos acessos com base em suas variabilidades genéticas não foi correlacionado com sua origem geográfica. Foram obtidos acessos que, pela alta produtividade de frutos, podem ser recomendados para cultivos experimentais em áreas de produtores. / Abstract: The present work was developed aiming at evaluating the morphoagronomic variability of Passiflora cincinnata Mast., which is distributed in different agroecological regions in Northeast Brazil. Data from 32 characters were used in experiments, carried out at Embrapa Tropical Semi-Arid, Petrolina-PE, Brazil, in a randomized complete block design with four replications. The behaviour of accesses was evaluated by univariate analysis and the studies related to the genetic diversity were done based on the multivariate procedures, using the general distance of Mahalanobis (Dø) and the grouping technique by canonic variables. The graphic dispersion of the accesses used the first canonic variables as axis. The strategies for collecting the accesses of P. cincinnata proved to be effective because the collected accesses showed genetic variability for all the descriptors used in the evaluation. The most important characters for the discrimination among accesses were: stem diameter (SD), number of leaf glands (NLG), number of glands per bract (NGB), pollen viability (PV), fruit mass (FM), seed mass (SM) and total fruit mass (TFM). However, as the environment influences the characters, the accesses must be evaluated in more than one environment. Grouping of accesses based on their genetic variability was not correlated with their geographic origin. Since some accesses showed high fruit productivity, they can be recommended to farmers for experimental growing. / Orientador: Norberto da Silva / Coorientador: Manoel Abilio de Queiróz / Banca: Rumy Goto / Banca: João Domingos Rodrigues / Banca: Grécia Cavalcanti da Silva / Banca: Natoniel Franklin de Melo / Doutor
6

The developmental and genetic basis of explosive pod-shatter in Cardamine hirsuta

Sarchet, Penny January 2012 (has links)
Dispersal is a key trait across biology. Within plants, a variety of explosive seed dispersal mechanisms are seen. Whilst ecological and mechanical studies have described this important evolutionary adaptation in many species, a genetic and developmental understanding of explosive seed dispersal is lacking. In this thesis, the morphology and development of the explosive seed pods of Cardamine hirsuta – a member of the Brassicaceae – are characterised in detail, with reference to its close relative, the model organism A. thaliana. Comparison of fruit morphology between these two species and across other Brassicacean species generated hypotheses regarding the function and polarity of morphological features. In order to identify genes that are necessary for C. hirsuta fruit development, a genetic screen was conducted and a range of mutants identified and subsequently characterised. Analysis of the indehiscent valveless (val) mutant revealed a loss of valve tissue and an expansion of valve margin identity in the silique. Mapping and sequencing identified a mutation in the MADS-box gene FRUITFULL (FUL), which results in a truncated protein, as the likely cause of the val phenotype. Consideration of ful mutants in C. hirsuta and A. thaliana allowed comparison of the genetic patterning of the fruit dehiscence zone in these two species. The genetic interactions between fruit mutants characterised in this thesis and mutants in shoot patterning genes revealed common regulatory networks underlying leaf and fruit development in C. hirsuta. Together, comparison of wild-type and mutant C. hirsuta siliques with those of A. thaliana and other Brassicacean species suggests that specialised cell layers within the valve silique region are of key importance to C. hirsuta’s explosive dehiscence mechanism.
7

液果の種子散布者としての中型哺乳類の特性ーおもにニホンザルを例としてー

大谷, 達也, OTANI, Tatsuya 12 1900 (has links)
農林水産研究情報センターで作成したPDFファイルを使用している。
8

The systematic significance of the fruit and seed morphology and anatomy in selected Oxalis L. (Oxalidaceae) species

Obone, Charline 12 1900 (has links)
Thesis (MSc (Botany and Zoology))--University of Stellenbosch, 2005. / At present a proper systematic classification of the southern African members of Oxalis L. (Oxalidaceae) does not exist. The most recent and comprehensive revision of the genus based on macro-morphological characters is out-dated (published 60 years ago (Salter, 1944)). The external morphology of the flowers of the southern African Oxalis species is reasonably wellstudied, but little is known about the anatomy thereof. A pilot study of fruit and seed morphology and anatomy of nine selected southern African Oxalis species (Obone, 2003) already revealed some trends to demarcate two main groups. This confirmed the systematic value of some of the characters already proposed by Salter (1944). The aim of the present study was to assess the potential systematic value of fruit and seed morphology and anatomy of 32 Oxalis species. The selection was done such that the included species would represent the main sections proposed by Salter (1944), the pollen types proposed by Dreyer (1996) and the different clades revealed by the phylogenetic tree compiled by Oberlander et al. (2004). Although the species sampling was very low (20% of the southern African taxa), 35 potentially informative characters were identified in fruit and seed morphology and anatomy. These characters may be grouped into three character types, namely autapomorphic characters, randomly distributed characters and systematically informative characters. The first two character types were particularly useful in species-specific characterization. The third group of linked characters could be used to demarcate two major groups of species, those producing endospermous seeds and those producing exendospermous seeds. The three types of characters may prove to be taxonomically informative if more species-inclusive studies are performed. The cluster analysis strongly supported the demarcation of endospermous and exendospermous groups with 100% bootstrap support. Low bootstrap values were observed for subgroups within each of the major groups. This is probably due to low taxon sampling. Therefore clustering based on fruit and seed morphology should be considered with extreme caution within the two groups. Despite these limitations of sample size, fruit and seed morphological and anatomical characters have proven to be systematically informative at the infra-generic level.
9

Fleshy-fruited invasive alien plants and frugivores in South Africa.

Jordaan, Lorinda A. January 2011 (has links)
South Africa is one of the world's most biologically invaded countries and has spent billions of rands on efforts to eradicate alien invasive plants. Chemical and mechanical control methods have varied in success and the need for integrated management strategies has been realised. This requires a better understanding of all aspects of the invasion process. Some of the most invasive plant species rely on vertebrate dispersers which facilitate long-distance seed dispersal. Frugivory is based on a mutualism in which the frugivores gain a resource and the plants benefit from seed dispersal away from the parent plant. Seed germination itself may either be enhanced, reduced or not affected at all after gut passage. The first aim of this study was to determine if generalist avian frugivores and a fruit bat species (Epomophorus wahlbergi) enhance or decrease seed germination of invasive alien plants in South Africa, by either pulp removal or seed coat abrasion, or if they serve as dispersers only. The second aim was to determine if avian frugivores are able to meet their energetic demands by feeding on a specific alien fruit diet. Finally, we also quantified the nutritional content and morphological characteristics of fleshy fruits of various invasive alien and exotic plant species. Avian frugivores: Red-winged Starlings (Onychognathus morio), Speckled Mousebirds (Colius striatus), and Dark-capped Bulbuls (Pycnonotus tricolor), varied in their effects on the germination success of seeds of four invasive alien species, namely: Lantana camara, Solanum mauritianum, Cinnamomum camphora, and Psidium guajava. However, this was not associated with differences in seed retention times. Similar germination success was observed for avian ingested and de-pulped seeds. This was also observed for fruit bat spat and depulped seeds of Psidium guajava, Melia azedarach, Eriobotrya japonica, and Morus alba. Therefore seed coat abrasion was not important for the germination of these fleshy-fruited invasive alien plants. Pulp removal resulted in significantly earlier seed germination as well as higher seed germination percentages than in the case of whole fruit controls for some of these invasive species. Gut passage is thus important for long-distance dispersal, and in some cases, for enhanced germination of seeds. The invasive Solanum mauritianum and indigenous congener S. giganteum showed similar germination responses, with both ingested and depulped seeds germinating profusely. However, S. giganteum benefited from pulp removal as seeds from whole fruits had less germination. Avian frugivores varied significantly in most energetic parameters calculated when given diets of invasive alien fruit. Speckled Mousebirds and Dark-capped Bulbuls were able to maintain body mass and efficiently process fruits of all four alien invasive plants, while Red-winged Starlings were only able to do so on lipid-rich C. camphora and sugar-rich S. mauritianum. Furthermore, frugivores also adjusted their feeding behavior by eating more nutritionally poor fruit and less energetically rewarding fruit. Fruit bats consumed more fruit per gram body mass than avian frugivores did. They therefore process proportionately more seeds than avian dispersers and thus their role in invasive seed dispersal, which has previously been underestimated particularly in South Africa, is highlighted. Fruits of invasive plant species were similar in morphology, but greater in nutritional content, than fruits of indigenous species. These fruits also contained small, light seeds with approximately only 30% having more than 10 seeds per fruit. The ability of frugivores to efficiently process these fruits and the greater nutritional rewards offered by these provide new insights into why these invasive fruits are preferred by frugivores. In addition, invasive alien plants may have a competitive edge over indigenous species because of their larger reproductive outputs and not necessarily because of greater germination success. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.
10

Evolution of Epiphytism and Fruit Traits Act Unevenly on the Diversification of the Species-Rich Genus Peperomia (Piperaceae)

Frenzke, Lena, Goetghebeur, Paul, Neinhuis, Christoph, Samain, Marie-Stephanie, Wanke, Stefan 19 January 2017 (has links) (PDF)
The species-rich genus Peperomia (Black Pepper relatives) is the only genus among early diverging angiosperms where epiphytism evolved. The majority of fruits of Peperomia release sticky secretions or exhibit hook-shaped appendages indicative of epizoochorous dispersal, which is in contrast to other flowering plants, where epiphytes are generally characterized by fruit morphological adaptations for anemochory or endozoochory. We investigate fruit characters using Cryo-SEM. Comparative phylogenetic analyses are applied for the first time to include life form and fruit character information to study diversification in Peperomia. Likelihood ratio tests uncover correlated character evolution. We demonstrate that diversification within Peperomia is not homogenous across its phylogeny, and that net diversification rates increase by twofold within the most species-rich subgenus. In contrast to former land plant studies that provide general evidence for increased diversification in epiphytic lineages, we demonstrate that the evolution of epiphytism within Peperomia predates the diversification shift. An epiphytic-dependent diversification is only observed for the background phylogeny. An elevated frequency of life form transitions between epiphytes and terrestrials and thus evolutionary flexibility of life forms is uncovered to coincide with the diversification shift. The evolution of fruits showing dispersal related structures is key to diversification in the foreground region of the phylogeny and postdates the evolution of epiphytism. We conclude that the success of Peperomia, measured in species numbers, is likely the result of enhanced vertical and horizontal dispersal ability and life form flexibility but not the evolution of epiphytism itself.

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