Thesis (M. Tech. (Agriculture)) -- Central University of Technology, Free State, 2013 / ntroduction: Good quality Eucalyptus is of importance to South Africa’s pulp and paper industry. Limited land is available for forestry, therefore Eucalyptus with genotypes for good pulp and paper qualities, particularly hybrids, are bred and cloned via cuttings. Although these Eucalyptus clones keep the favourable genotypes in the population, many have difficulty with rooting. Research has shown that rhizobacteria can improve rooting. Thus, one strategy to enhance the rooting of cuttings is to use rhizobacterial preparations. The aim of this study was to characterise rhizobacterial communities of Eucalyptus hybrid and species and identify possible plant-growth promoting rhizobacteria (PGPR). Materials and methods: Rhizospheric samples were collected from Eucalyptus hybrids and species. The rhizobacterial communities were characterised using fatty acid methyl esters (FAME) analysis and denaturing gradient gel electrophoresis (DGGE). DGGE fragments were further sequenced to identify rhizobacteria. Results and discussion: FAME analysis successfully achieved a broad characterisation of the Eucalyptus hybrid and species rhizobacterial communities based on their fatty acid composition. Myristic acid (C14:0) was the most abundant fatty acid. DGGE profiles gave a molecular profile of the Eucalyptus hybrid and species rhizobacterial communities based on their DNA composition. Nitrosomona eutropha was present in all samples which illustrates a nitrogen-rich environment. Adhaenbacter aquaticus was unique to the better rooting Eucalyptus hybrid GU111. Conclusion: This study provided some insight into the diversity of rhizobacterial communities of Eucalyptus hybrids and species. Possible PGPR were identified and the observation made that the nature of the soil environment changes with the aging of the associated host. These findings allow further investigation into the formulation of potential rhizobacterial preparations for rooting enhancement of Eucalyptus cuttings.

La phylogénie permet de reconstituer l'histoire évolutive de séquences ainsi que des espèces qui les portent. Les récents progrès des méthodes de séquençage ont permis une inflation du nombre de séquences disponibles et donc du nombre d'arbres de gènes qu'il est possible de construire. La question qui se pose est alors d'optimiser la recherche d'informations dans ces arbres. Cette recherche doit être à la fois exhaustive et efficace. Pour ce faire, mon travail de thèse a consisté en l'écriture puis en l'utilisation d'un ensemble de programmes capables de parcourir et d'annoter les arbres phylogénétiques. Cet ensemble de programmes porte le nom de TPMS (Tree Pattern Matching Suite). Le premier de ces programmes (tpms_query) permet d'effectuer l'interrogation de collections à l'aide d'un formalisme dédie. Les possibilités qu'il offre sont : La détection de transferts horizontaux : Si un arbre de gènes présente une espèce branchée dans un arbre au milieu d'un groupe monophylétique d'espèces avec lesquelles elle n'est pas apparentée, on peut supposer qu'il s'agit d'un transfert horizontal, si ces organismes sont des procaryotes ou des eucaryotes unicellulaires. La détection d'orthologie : Si une partie d'un arbre de gènes correspond exactement à l'arbre des espèces, on peut alors supposer que ces gènes sont un ensemble de gènes d'orthologues. La validation de phylogénies connues : Quand l'arbre des espèces donne lieu à des débats, il peut est possible d'interroger une large collection d'arbres de gènes pour voir combien de familles de gènes correspondent à chaque hypothèse. Un autre programme, tpms_computations, permet d'effectuer des opérations en parallèle sur tous les arbres, et propose notamment l'enracinement automatique des arbres via différents critères, ainsi que l'extraction de sous arbres d'orthologues (séquence unique par espèce). Il propose aussi une méthode de détection automatique d'incongruences. La thèse présente le contexte, les différents algorithmes à la base de ces programmes, ainsi que plusieurs utilisations qui en ont été faites / Phylogeny allows to reconstruct evolutionnary history of sequences and species that carry them. Recent progress in sequencing methods produced a growing number of available sequences, and so of number of gene trees that one can build. One of the consecutive issues is to optimise the extraction of information from the trees. Such an extraction should be complete and efficient. To address this, my thesis consisted in writing and then using a suite of programs which aim to browse and annotate phylogenic trees. This program suite is named TPMS (Tree Pattern Matching Suite). It browses and annotates trees with several algorithms. The first of them, tpms_query consists in querying collections using a dedicated formalism. This allows to: Detect horizontal transfers If, in a gene tree, a species is nested in a monophyletic group of unrelated species, one can infer this is a horizontal transfer, if this organisms are prokaryotic (also concerning some unicellular eukaryotes). Orthology detection: if a part of a gene tree exactly matches to the species tree, one can suppose these genes are set of orthologues. Validating known phylogenies: when controversy exists concerning the species tree, it is possible to query a lange collection of gene trees to perform a count of families matching to each hypothesis. Another program allows to perform parallel operations on all the trees, such as automating rooting of trees via different criterions. It also allows an automatic detection of incongruencies. The thesis introduces the context, different algorithms which the programs are based on, and several using performed with it

A variabilidade das propriedades físicas do solo apresenta impacto sobre o desempenho das atividades de produção agrícola. Métodos indiretos para obtenção de informações sobre as propriedades do solo com interesse agronômico são utilizados com o intuito de favorecer o uso de insumos de modo mais adequado. A condutividade elétrica aparente do solo (CEa) é influenciada por diversas propriedades, muitas delas interrelacionadas e com variabilidade em curta distância, sendo difícil a separação dos diversos fatores. As medidas de CEa são usualmente tomadas em superfície com arranjos de eletrodos para prospecção de um volume de solo proporcional à distância entre eles. Neste trabalho foi utilizada uma metodologia que permitiu identificar algumas das propriedades com maior impacto sobre a CEa, merecendo destaque aquelas relacionadas ao espaço poroso do solo. A caracterização detalhada da variação da CEa ao longo do perfil do solo e sua comparação com aquela obtida a partir da sondagem elétrica vertical permitiram identificar algumas limitações desta técnica. A presença de camadas com variação de diversas propriedades físicas e de umidade no perfil do solo alterou os valores observados em superfície. A relação entre a distância de separação dos eletrodos no arranjo com quatro pontas igualmente espaçadas, e a profundidade de prospecção, coeficiente k, oscilou entre 0,35 e 0,70 para os solos LVd, LAd e PVe avaliados. A sondagem elétrica empregada na caracterização de variabilidade espacial na horizontal e em profundidade em uma área com teores de argila oscilando entre 150 e 379 g kg-1 na camada 0 a 0,2 m e entre 225 e 326 g kg-1 na camada 0,6 a 0,8 m apresentou resultado satisfatório. / The variability of soil physical properties has an impact on the performance of agricultural production activities. Indirect methods for obtaining information on the soil properties with agronomic interest are used to allow the use of inputs more appropriately. The apparent soil electrical conductivity ( ECa ) is influenced by several properties , many of them interrelated and presenting variability in short distances, being difficult to separate the various factors. ECa measures are usually taken in surface, using electrode arrangements for prospecting a soil volume proportional to the distance between them. In this work, a methodology was used that identified some of the properties with the greatest impact on the ECa, with emphasis to those related to soil porous space. The detailed characterization of the variation of ECw throughout the soil profile and its comparison with that obtained from the vertical electrical sounding was carried to identify certain limitations of this technique. The presence of several layers with varying physical properties and moisture in the soil profile changed values obtained from surface sounding. The relationship between the separation of the electrodes in the array with four points equally spaced, the Wenner array, and the depth of exploration, coefficient k, ranged between 0.35 and 0.70 for the soils LVd , LAd PVe and evaluated. A survey was done for the ECa characterization of spatial variability in the horizontal and along soil profile in an area with clay content ranging from 150 to 379 g kg - 1 in the layer from 0 to 0.2 m and between 225 and 326 g kg - 1 in layer 0, 6 to 0.8 m. The use of ECa for characterizing this variability showed satisfactory results.

O trabalho realizado constitui uma estratégia em Biotecnologia de Plantas para a investigação dos esquemas bioquímicos controladores da diferenciação celular no processo de enraizamento. Através da técnica da cultura de tecidos \"in vitro\" foram micropropagados clones de Eucalyptus grandis HILL ex MAIDEN (GO 250, GO 682 e GO 669) selecionadas no CEBTEC/USP. Em uma pesquisa preliminar foram estabelecidas e multiplicadas gemas, seguida de testes da composição de meios de cultura para elongação e enraizamento. Foram estudadas diversas possibilidades de balanceamento das substâncias reguladoras de crescimento - ácido indolilbutírico (AIB)/ benzilaminopurina (BAP). Os clones apresentaram comportamentos anatômico-fisiológicos (massa fresca e seca; teor protéico; taxas de multiplicação das brotações epicórmicas, elongação e enraizamento) diferenciados entre si. As frequências de enraizamento mostraram-se superiores às já observadas por outros autores. Foram estabelecidas, ainda, algumas alterações na composição dos meios de cultura empregados. Através de experimentos cinéticos foram determinados os padrões de indução e/ou inibição das enzimas fenilalanina amônia-liase (PAL) e glucose 6-fosfato-desidrogenase (G-6P-DH) importantes para a biossíntese de compostos flavonóides, considerados como os principais cofatores das auxinas endógenas no complexo iniciador do enraizamento. Verificou-se que embora o suprimento exógeno crescente de AIB tenha resultado em maiores taxas de enraizamento, as atividades da PAL e G-6P-DH não se mostraram significativamente alteradas. Contudo, foi observado também que as gemas que enraizaram apresentaram atividade da PAL significativamente superior, evidenciando maior fluxo do Metabolismo do Fenilpropano durante o enraizamento. / This study constitutes a strategy in Plant Biotechnology with the purpose to investigate the regulating biochemical development of the cellular differentiation in the rooting process. Through plant tissue culture \"in vitro\" technique, clones of Eucalyptus grandis Hill ex Maiden (GO 250, GO 682 e GO 669) selected at CEBTEC/USP, were micropropagated. In a preliminary study shoots were multiplied, followed by tests of media culture composition for shoot elongation and root initiation. Several possibilities and rates of plant growth regulators, indolilbutyric acid (IBA)/benzylaminopurine (BAP) were studied. The clones showed different anatomic-physiological behaviours (fresh and oven-dry weight; proteic content; epicormic shoots multiplication rates, elongation and rooting). The frequences of rooting were higher than those described by other authors. Some modifications in the composition of used cuIture media were also defined. Through kinetic experiments, induction and inhibition patterns of phenylalanine ammonia-lyase (PAL) and glucose 6- phosphate-dehydrogenase (G-6P-DH) important to the biossyntesis of flavonoid compounds were determined. They were considered as the main cofactors of endogenous auxins in the root stimulating complex. Although, the increasing exogenous supply of AIB resulted in higher rooting rates, the activities of PAl and G-6P-DH enzyme did not present alterations. However, it was also observed that shoots wich rooted, in the treatments, showed higher PAL activity. resulting in higher flux of phenylpropanoid metabolism during the rooting.

Submitted by Maria Beatriz Vieira (mbeatriz.vieira@gmail.com) on 2017-06-21T15:10:36Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_camila_fernanda_junkes.pdf: 1289430 bytes, checksum: c3ed40aa6f1d8b5187b0894e8ea77b9b (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-06-21T18:58:38Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_camila_fernanda_junkes.pdf: 1289430 bytes, checksum: c3ed40aa6f1d8b5187b0894e8ea77b9b (MD5) / Made available in DSpace on 2017-06-21T18:58:38Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_camila_fernanda_junkes.pdf: 1289430 bytes, checksum: c3ed40aa6f1d8b5187b0894e8ea77b9b (MD5) Previous issue date: 2015-02-26 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / A macieira é uma frutífera lenhosa amplamente difundida no mundo. Suas mudas são propagadas por estaquia e os porta-enxertos por mergulhia de cepa devido ao alto grau de incompatibilidade entre os genótipos e grande período de juvenilidade. Os porta-enxertos conferem diferenças no vigor e resistência a doenças à cultivar copa, sendo mais utilizadas no Brasil as cultivares M.9 (anão) e ‘Marubakaido’ (vigoroso). Devido a problemas fitossanitários e de rendimento da técnica de propagação vegetativa, a micropropagação surge como uma tecnologia útil tanto a nível de pesquisa quanto a nível comercial. No entanto, cada genótipo de macieira responde de forma diferente aos estímulos in vitro, de forma que deve-se adequar os protocolos em função da cultivar em estudo. Neste sentido, o presente trabalho teve como objetivo traçar os primeiros estudos sobre a utilização de sistema de imersão temporária (SIT) na micropropagação de ‘Marubakaido’. Para tal, testes preliminares sobre a influência do tipo de explante (apical ou axilar) foram realizados via sistema convencional em três variações do meio MS (composição convencional; NH4NO3 e KNO3 reduzido a ¾; e formulação industrial Himedia) suplementados com 0,8 mg.L-1 de BAP, 100 mg.L-1 de mio-inositol, 30 g.L-1 de sacarose e 7 g.L-1 de ágar. Após 45 dias observou-se que o meio Himedia conferiu maior homogeneidade entre as brotações, enquanto o tipo de explante não afetou a resposta quanto ao número e comprimento médio das brotações obtidas, podendo ambos serem utilizados sem prejuízo às taxas de multiplicação. Em seguida, os mesmos meios foram empregados na comparação entre micropropagação de explantes axilares de ‘Marubakaido’ em sistema convencional e SIT. Após 4 semanas verificou-se que as taxas de hiperidricidade obtidas em SIT foram muito mais elevadas do que em sistema convencional, chegando a 100% para meio MS. Uma intensa formação de calos foi observada nos meios MS e MS ¾ neste mesmo sistema, que impediram o desenvolvimento dos explantes. Quanto ao número médio e comprimento de brotações, o meio Himedia em SIT apresentou melhores resultados quando comparado a todos os tratamentos para meio e sistema (6,3 brotações por explante e 3,7 cm). O enraizamento das brotações produzidas em SIT com meio Himedia foi maior quando as brotações foram destacadas se comparadas com brotações mantidas em tufos (74,1% e 62,5% respectivamente), e a aclimatização das microestacas enraizadas resultou em 88,5% de sobrevivência após 21 dias. Embora os resultados tenham sido promissores, novos estudos ainda precisam ser realizados na tentativa de aperfeiçoar estes protocolos para ‘Marubakaido’, como alterações na composição hormonal, tempo e frequência de passagem do meio para os explantes ou enraizamento ao abrigo de luz. / The apple tree is a woody fruit widespread in the world. Your plants are propagated by cuttings and rootstocks by layering strain due to the high level of incompatibility between the genotypes and great period of juvenility. Rootstocks confer differences in vigor and disease resistance to scion, being more used in Brazil the cultivars M.9 (dwarf) and 'Marubakaido' (vigorous). Due to phytosanitary problems and yield of vegetative propagation technique, micropropagation appears as a useful technology at level of research or commercially. However, each apple genotype responds differently to in vitro stimuli, so the protocols must be adapted according to cultivar in study. Herewith, the present research aimed to draw the first studies about the use of temporary immersion system (TIS) in ‘Marubakaido's micropropagation. For this purpose, preliminary tests about the influence of the type of explant (apical or axillary) were performed via conventional system in three variations of the MS media (conventional composition; NH4NO3 and KNO3 reduced to ¾, and industrial formulation Himedia) supplemented with 0.8 mg.L-1 BAP, 100 mg L-1 myo-inositol, 30 g L-1 sucrose and 7 g L-1 agar. After 45 days it was observed that the Himedia conferred greater homogeneity among the shoots, while the type of explant did not affect the response in the average of number and length of shoots obtained, and both can be used without prejudice to the multiplication rates. Then, the same media were used in the comparison of micropropagation of ‘Marubakaido’ axillary explants between conventional system and TIS. After 4 weeks it was found that the hyperhydricity rates obtained with TIS were much higher than in conventional system, reaching 100% at MS medium. An intense callus formation was observed in MS and MS ¾ media at same system, which stopped the development of the explants. For the mean of number and length shoots, the Himedia composition in TIS showed better results when compared to all treatments for media and system (6.3 shoots per explant and 3.7 cm). Rooting of shoots produced in TIS with Himedia was higher when the shoots were separated compared with shoots kept in tufts (74.1% and 62.5% respectively), and acclimatization of the rooted microcutting resulted in 88.5% of survival after 21 days. Although the results have been promising, further studies still need to be performed to improve these protocols to ‘Marubakaido’, as changes in hormonal composition, time and frequency for passage of media to the explants or rooting under darkness.

Made available in DSpace on 2017-07-10T17:37:31Z (GMT). No. of bitstreams: 1 Tania Pires da Silva.pdf: 493041 bytes, checksum: 3d9daa71e02d7c679bf5b90cf21bb3c5 (MD5) Previous issue date: 2008-12-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of the work was to evaluate the phytotechnical performance of different rootstocks in the formation level on field conditions and the initial development of the graft, as well as the application of auxiliaries technicians to the root potential increment of the rootstocks cuttings of VR 043-43 in nursery conditions. Ligneous cuttings from grapevine VR 043-43 , measuring 20 cm, were stratified for 48h (under the temperature of 4 oC), part of the cuttings were kept under environment temperature (25 } 5 oC). All the cuttings were treated with indolbutyric acid (IBA) in different concentrations of 0, 1.000, 2.000 and 3.000 mgL-1, associated and not associated to boric acid at concentration of 150 μg L-1 for 10sec. The cuttings were planted into polyethylene plastic bags (capacity of 2,5L), filled with clay soil. They were kept in nursery made of shading screen providing 50% of luminosity. The evaluations occurred 120 days after the experiment deployment. In November, the seedlings originated from the rooted cuttings of 17 grapevine rootstocks ( SO4 , Teleki 8B , Harmony , Golia , Riparia de Traviu , Paulsen , 420 A , 99R , 5C , RR101-14 , Kober 5BB , Rupestris Du Lot , IAC 313 Tropical , IAC 766 Campinas , IAC 572 Jales , VR 043-43 and IAC 571-6 Jundiai ) were taken to the field under subtropical conditions (24o33 40 S and 54o04 12 W, 420 m height and Cfa Koppen climate, with annual maximum average temperature of 28,5 oC and minimum of 17,5 oC). After four months, it was evaluated the anthracnose and rust severity on the grapevine leaf sprouting from the rootstocks and more five months of vigor (total branch number, average diameter, biggest branch length and total leaf area fresh mass). In the sequence, it was performed winter graft using BRS Violeta . The evaluated characteristics for this part of the experiment were percentage of tissue union, diameter and graft average length, which happened after 60 days of grafting. It was concluded that the stratification of the cutting is not fundamental to increase the efficiency of the rooting process of the rootstock VR 043-43 . The cuttings should only be treated with IBA at 3.000 mg L-1 in association to boric acid. The rootstocks IAC 572 Jales and IAC 313 Tropical were resistant to the anthracnose and rust. The rootstock IAC 572 Jales was the one that showed greater performance on field, before grafting. The rootstocks SO4 , Harmony , Paulsen and IAC 766 Campinas showed greater vigor to the development of the graft BRS Violeta / O trabalho teve como objetivo avaliar o desempenho vegetativo de diferentes porta-enxertos na fase de formacao a campo e o desenvolvimento inicial do enxerto, bem como o emprego de tecnicas auxiliares para o incremento do potencial rizogenico de estacas do porta-enxerto VR 043-43 em condicoes de viveiro. Estacas caulinares lenhosas de 20 cm comprimento do porta-enxerto de videira VR 043-43 , estratificadas por 48 h (sob temperatura de 4 oC) ou não (ambiente de 25o } 5 oC), foram tratadas em solucao de acido indolbutirico (AIB) nas concentracoes de 0, 1.000, 2.000 e 3.000 mg L-1, associado ou nao com acido borico a 150 μg L-1, por 10 seg. As estacas foram plantadas em saco plastico de polietileno (capacidade de 2,5 L), contendo solo com textura argilosa como substrato e mantidas sob viveiro constituido de tela de sombreamento de 50% de luminosidade, sendo avaliadas apos 120 dias. Em novembro, mudas oriundas de estacas enraizadas de 17 porta-enxertos de videira ( SO4 , Teleki 8B , Harmony , Golia , Riparia de Traviu , Paulsen , 420 A , 99R , 5C , RR101-14 , Kober 5BB , Rupestris Du Lot , IAC 313 Tropical , IAC 766 Campinas , IAC 572 Jales , VR 043-43 e IAC 571-6 Jundiai ) foram levadas a campo, em condicoes subtropicais (24o33 40 S e 54o04 12 W, altitude de 420 m e clima Cfa Koppen, com temperatura media maxima anual de 28,5 oC e minima de 17,5 oC). Passados quatro meses, avaliou-se a severidade da antracnose e ferrugem da videira nas folhas das brotacoes dos porta-enxertos e mais cinco meses o vigor dos mesmos (numero total de ramos, diametro medio, comprimento do maior ramo e massa fresca total media dos ramos). Em seguida, realizou-se a enxertia invernal com garfos da videira BRS Violeta e avaliou-se apos 60 dias a porcentagem de pegamento, o diametro e o comprimento medio do enxerto. Concluiu-se que a estratificacao das estacas nao e fundamental para que haja maior eficiencia do processo de enraizamento do porta-enxerto VR 043-43 , devendo as estacas apenas serem tratadas com 3.000 mg L-1 de AIB, associada ao acido borico. Os porta-enxertos IAC 572 Jales e IAC 313 Tropical foram resistentes a antracnose e a ferrugem. O porta-enxerto IAC 572 Jales foi o que promoveu maior desempenho a campo, previamente a operacao de enxertia. Os porta-enxertos SO4 , Harmony , Paulsen e IAC 766 Campinas promoveram maior vigor ao desenvolvimento do enxerto de BRS Violeta

Clones of the Eucalyptus grandis x Eucayptus nitens (GN) hybrids were produced and selected through the CSIR‟s breeding programmes for colder plantation sites in South Africa. Some GN clones consistently exhibit high and superior pulp properties, which makes them valuable for commercial plantations in South Africa. In nurseries, stockplants are usually seven cm in length and maintained at high (100 x1.5 m-2) planting density. However, rooting frequency varies with season and little is known about the impact of position of cuttings on overall rooting frequency of a clone. The aim of this study was to investigate the effect of size and planting density of stockplants in mini-hedges, on the yield and subsequent rooting of cuttings from various positions of GN clones of known rooting potential (i.e. GN 018B: difficult-to-root and PP 2107: easy-to-root clones). Stockplants (10 cm vs. 20 cm) were established at high (100 x 1.5 m-2) and at low (25 x 1.5 m-2) densities for GN 018B and PP 2107 under commercial nursery conditions in a polyethylene tunnel. Cuttings were harvested every two to three weeks in September-October 2010 (spring), December 2010-January 2011 (summer), April-May 2011 (autumn) and June-July 2011 (winter). The harvested material was 5 – 7 cm in length and the light intensity received by individual stockplants at the two planting density levels was recorded. Harvested cuttings from the three positions (apical, middle and basal shoots) were used for: (i) rooting experiments under nursery conditions, (ii) bio-stimulant analysis using the mung bean bioassay, and (iii) analysis of soluble sugars. Between spring and summer 2010, the two GN clones established at low density yielded a similar number of cuttings, but differences in the rooting frequencies were significant in favour of PP 2107 clone. Similar observations were made at high density in terms of production of cuttings, but the significant differences in the rooting observations were reversed between the clones. The GN 018B clone had low rooting rates in summer under nursery conditions but its tissue extracts promoted higher rooting in the bioassay during that time, when compared to spring. Spring and summer had similar effects on rooting responses of PP 2107 cuttings in nursery and bioassay experiments. For both clones, short stockplants produced fewer cuttings but had a higher rooting frequency than cuttings from tall stockplants, with a high rooting frequency recorded from basal cuttings. Similar results were observed in the bioassay experiments which showed high rooting potential of mung bean hypocotyls cuttings using tissue extracts of PP 2107 cuttings maintained at high planting density. Although apical cutting tissues had high concentration of sugars (i.e. sucrose, glucose and fructose), their rooting rates were usually lower at high and low planting density compared to middle and basal cuttings. Sucrose concentration was the highest sugar present in stockplants grown under low planting density. A higher and lower rooting frequency was also observed in autumn although the two clones responded differently to Quambalaria eucalypti (Sporothrix eucalypti) disease infestations. Position, size and genotype had a significant impact on type and concentration of sugar (i.e. sucrose, glucose and fructose), particularly in PP 2107 clone, although rooting rates in the bioassay did not correlate with sugar contents of Eucalyptus cuttings. High carbohydrate (i.e. soluble sugar) content and auxin concentration increased production and subsequent rooting of cuttings across both clones, particularly in spring. Furthermore, rooting was enhanced by relatively higher light intensity intercepted by individual stockplants and in particular the GN 018B clone. Light intensity in the high and low planting densities caused variation in the rooting frequencies thereby increasing or decreasing soluble sugar and auxin concentrations of the two clones. Light intensity and fertiliser concentration received by tall and short stockplants impacted on endogenous hormone levels thereby increasing or decreasing rooting. High sugar concentration levels of PP 2107 clone increased its susceptibility to fungal infection thereby decreasing its rooting frequency in autumn, as its rooting rates increased in winter. Overall results of the investigation revealed that PP 2107 clone has higher rooting potential than GN 018B clone, in particular at high planting density and if stockplants are not infected by fungal diseases. Higher sugar levels were recorded in spring for PP 2107, although rooting rates of mung bean hypocotyl cuttings were higher in summer for GN 018B, suggesting that sugars have nothing to do with rooting of GN cuttings. Season, planting density and size of stockplants affect the rooting frequency of GN clone. Thus, short stockplants maintained at low and high planting densities are recommended for GN 018B and PP 2107 respectively, although the impacts of fertilisers and pathogen resistance on rooting rates still need to be investigated under similar conditions. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.

Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv. / Härtill 5 uppsatser.

Made available in DSpace on 2014-06-11T19:32:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-08-15Bitstream added on 2014-06-13T19:03:07Z : No. of bitstreams: 1 souza_av_dr_botfca.pdf: 1549773 bytes, checksum: 84b4a67f035a5e2a2ded161bbf59589c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Outra / O bioma Cerrado e uma das regioes mais ricas do Brasil no tocante a diversidade de plantas medicinais, sendo atualmente, considerado uma area ghotspots h devido o alto grau de endemismo das especies e a velocidade de degradacao que vem sofrendo. Anemopaegma arvense, Mandevilla illustris e Mandevilla velutina, sao plantas medicinais endemicas do cerrado, muito utilizadas na medicina popular devido suas propriedades terapeuticas. A coleta indiscriminada realizada pela populacao, como tambem por laboratorios farmaceuticos para a fabricacao de medicamentos, tem colocado essas especies em risco de extincao. Ferramentas biotecnologicas como a tecnica da micropropagacao e biologia molecular para analise do DNA, tem sido amplamente usadas para a producao, conservacao e analise da diversidade genetica de especies nativas. Neste contexto, o presente trabalho teve como objetivos estudar a variabilidade genetica em diferentes populacoes de M. velutina por meio do marcador molecular RAPD e estabelecer a conservacao em bancos de germoplasma in vitro; desenvolver protocolos eficientes de enraizamento in vitro para A. arvense, M. illustris e M. velutina; verificar a ocorrencia e identificar especies de micorrizas, avaliando a colonizacao em raizes de plantas de diferentes populacoes e variedades de A. arvense. Para os estudos de enraizamento in vitro, as brotacoes foram submetidas a acao de diferentes substancias que apresentam efeito sobre a formacao de raizes adventicias, sob variadas condicoes. Para a analise da diversidade genetica, utilizou-se a tecnica de Polimosfirmo de DNA Amplificado ao Acaso (RAPD) e para os estudos micorrizicos, realizou-se a avaliacao da infeccao micorrizica nas raizes e a identificacao de especies de fungos micorrizicos extraidos do solo. As especies comportaram-se de maneira diferente quanto a inducao de raizes adventicias in vitro, mostrando a influencia direta do genotipo no processo de enraizamento. Para as especies M. illustris / The Bioma Cerrado is one of the richest regions in Brazil due to the variety of native medicinal plants, and nowadays it is considered a hotspot area because of the high degree of endemism of the species and the speed of degradation that it has been submitted. Anemopaegma arvense, Mandevilla illustris and Mandevilla velutina, are medicinal plants endemic of Cerrado very used in the popular medicine due to their therapeutic properties. The indiscriminate collection accomplished by the population, as well by pharmaceutical laboratories for the formulation of medicines, has put those species in risk of extinction. Biotechnological tools as the technique of micropropagation and molecular biology for the analysis of the DNA, have been widely used for the production, conservation and analysis of the genetic diversity of native species. In this context, the current work was investigate the genetic variability in different populations of M. velutina by means of molecular marker RAPD and to establish a protocol for in vitro conservation in germplasm bank; to develop efficient protocol of in vitro rooting for A. arvense, M. illustris and M. velutina; to verify the occurrence and to identify species of mycorrhiza, colonizing plant roots of different populations and varieties of A. arvense. For the studies of in vitro rooting, the plantlets were exposed to the action of different exogenous substances that a effect the formation of adventious roots, under several conditions. For the analysis of genetic diversity, it was used the technique of Random Amplified Polymorphic DNA at (RAPD) and for the studies on influence of mycorrhizal infection on root development and identification of species of fungi present in the soil. The species behaved in a different ways of induction of adventious roots in vitro. For the species M. illustris and A. arvense, 73,3% e 50% of plantlets rooted after fifteen days in treatment with 1 and 2 mg.L-1 of NAA, respectively. For M.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / Erva-mate (Ilex paraguariensis) has an economical and environmental importance to the southern area of Brazil. However, there is no enough technologies of vegetative propagation, which are important to improve yield and quality. This study had as objectives to evaluate the propagation of erva-mate trees trough cuttings and to establish an ex vitro acclimatization and micro-cutting rooting protocols from embryo cultures. Vegetative propagation potential was evaluated considering shading intensity of the stock plant and origin and size of the cuttings. Cuttings were grabbed from stock plants growing under light or shade conditions and prepared in two types (one-bud and regular types). The evaluations were the percentage of lived and died cuttings, cuttings unchanged, shoot and callus growth, shoot length, rooting, leaf survival, number and length of roots and number and length of leaves in new shoots. For acclimatization and ex vitro rooting were evaluated five concentrations of indol butyric acid (IBA) (0; 250; 500; 1,000 and 2,000 ppm) and five substrates (vermiculite, sand, carbonized rice hull, commercial substrate of pinus bark, and coconut bark). The evaluations were the percentage of cuttings unchanged, callus formation, rooting and mortality, number and length of roots, micro-cutting length, fresh weight of roots, and number of leaves in new shoots. The highest cutting unchanged was gotten with cuttings from plants growing in light. Callus formation, presence of leaves and new shoot growth affected rooting. Cuttings collected from vegetative propagated plants showed higher percentage of rooting and root length. The highest rooting percentage and micro-cutting growth were found with 1,000 ppm of IBA during acclimatization period. Acclimatization and ex vitro rooting of erva-mate micro-cuttings can be done in the substrate of carbonized rice hull and commercial substrate of pinus bark. / A erva-mate (Ilex paraguariensis) assume uma importância ambiental e socioeconômica para a região sul do Brasil, porém carece de tecnologias de propagação vegetativa necessárias para o aumento da produção e da qualidade. O presente estudo teve por objetivos analisar a propagação via estaquia de material adulto e estabelecer a aclimatização ex vitro e o enraizamento de microestacas originadas de cultivo de embriões de erva-mate. Para a estaquia, analisaram-se o efeito do nível de sombreamento da planta matriz, a origem e o tamanho da estaca, avaliando o potencial de propagação vegetativa. As estacas foram coletadas de plantas matrizes de dois níveis de sombreamento (crescimento a pleno sol e sombreado), de duas origens (seminal e propagada vegetativamente) e de dois tipos (estaca convencional e de gema única). Os parâmetros utilizados para avaliar as estacas foram a porcentagem de estacas vivas e mortas, de estacas inalteradas, emissão e comprimento de brotos, formação de calos, enraizamento, permanência das folhas primárias, número e comprimento de raízes e número e comprimento de folhas dos brotos. Na aclimatização e enraizamento ex vitro de erva-mate foram testadas cinco concentrações de ácido indol butírico (AIB) (0, 250, 500, 1.000 e 2.000 ppm), e cinco tipos de substratos (vermiculita, areia, casca de arroz carbonizada, substrato comercial a base de casca de pinus e casca de coco), visando o enraizamento de microestacas. As microestacas foram avaliadas quanto a porcentagem de estacas inalteradas, de formação de calos, de enraizamento e de mortalidade, número de raízes, comprimento de raízes, tamanho total da microestaca, biomassa radicular e número de folhas dos brotos. Estaca coletada de planta matriz em pleno sol apresentou maiores porcentagens de estacas inalteradas. A presença de calo, das folhas primárias e a emissão de brotos afetaram o enraizamento. Estacas coletadas de matrizes propagadas vegetativamente apresentam maior taxa de enraizamento e comprimento de raízes. Na microestaquia, a concentração de 1.000 ppm de AIB foi eficiente para o enraizamento e crescimento de microestacas na aclimatização. Microestacas de erva-mate podem ser aclimatizadas e enraizadas ex vitro em substrato de casca de arroz carbonizada e em substrato comercial a base de casca de pinus.