Orientador: Luiz de Souza Corrêa / Banca: Heloiza Ferreira Alves do Prado / Banca: Aline Redondo Martins / Banca: Silvia Correa Santos / Banca: Samuel Ferrari / Resumo: O pinhão manso pode ser propagado de forma vegetativa através de estacas e enxertia ou via seminífera. Por ser uma planta de polinização cruzada, quando propagado via sementes origina indivíduos com alta variabilidade genética, produção mais tardia, no entanto com desenvolvimento de raiz pivotante, o que confere às plantas maior vigor e resistência a secas prolongadas. Quando propagado vegetativamente apresenta as mesmas características da planta mãe, desenvolvem apenas raízes secundárias, e são mais precoces na produção de frutos. A técnica da enxertia também confere maior precocidade às plantas enxertas, com a vantagem de poder combinar resistência do porta enxerto com produtividade do enxerto. O presente trabalho teve como objetivo desenvolver técnicas de propagação para pinhão manso através de estacas, sistemas de enxertia e sementes. Foram desenvolvidos 4 experimentos, sendo que o primeiro experimento avaliou o pegamento por meio de avaliações do desenvolvimento vegetativo de diferentes tipos de estacas (basal, mediana e apical) de pinhão manso em dois tipos de substratos (areia e vermiculita). O segundo avaliou o enraizamento de estacas (basal, mediana e apical) provenientes de ramos armazenados em condições ambientes por 30 e 60 dias. O terceiro experimento objetivou avaliar o efeito do antioxidante ácido cítrico nos cortes antes da realização da enxertia e o uso de dois sistemas de fixação dos enxertos, barbante e gaze. O último experimento avaliou a germinação de sementes e o desenvolvimento inicial de plântulas de pinhão manso em função do ambiente e do tempo de armazenamento das sementes. Quando propagado por estacas e utilizando diferentes substratos para enraizamento, as estacas basais de pinhão manso proporcionam uma maior porcentagem de estacas vivas, assim como estacas instaladas em vermiculita também apresentaram uma maior porcentagem de ... / Abstract: Jatropha can be propagated vegetatively by cuttings and grafting or by seeds. It is a allogamous plant, when propagated via seed originates progenies with high genetic variability, later production, but with developed tap root which gives great plant vigor and resistance to prolonged drought. When propagated vegetatively presents the same characteristics as the parental plant, just secondary roots were developed, but with early fruit production. The technique of grafting also gives more precocity to the plants, with the advantage of combining rootstock resistance with the graft yield. The present study aimed to develop techniques for Jatropha propagation by cuttings, grafting and seed systems. Four experiments were conducted, and the first one aimed to test the rooting and vegetative development of plants from different types of cuttings (basal, middle and apical) on two types of substrates (sand and vermiculite). The second evaluated the rooting of cuttings (basal, middle and apical) from branches stored in ambient conditions for 30 and 60 days. The third experiment aimed to evaluate the antioxidant effect of citric acid in cuts before grafting and the use of two systems for setting grafts string and gauze. The last experiment evaluated seed germination and early seedling development of Jatropha as a function of environment and time of seed storage.When propagated by cuttings and using different substrates for rooting, Jatropha basal cuttings provide a higher percentage of living cuttings, as well as cuttings installed in vermiculite also had a higher percentage of survival. At the end of the experiment the basal cuttings were superior to others in all variables analyzed, as well as those in vermiculite. Regarding storage of Jatropha branches for later use, it is concluded that the storage of Jatropha branches up to 30 days is feasible under the conditions studied andthe basal part of the cuttings ... / Doutor

Orientador: Gisela Ferreira / Coorientador: Ivan de Godoy Maia / Banca: Magali Ribeiro da Silva / Banca: Carmen Silvia Fernandes Boaro / Banca: Ivan de la Cruz Chacón / Banca: Celso Luis Marino / Resumo: A enxertia é utilizada de maneira eficaz para o cultivo de espécies frutíferas comercias, uma vez que é necessário garantir as caraterísticas genéticas de espécies produtivas com o emprego de clones selecionados. Apesar da enxertia ser técnica comum e amplamente difundida, os mecanismos de compatibilidade em frutíferas lenhosas ainda não estão bem elucidados. Desta forma, o objetivo desta tese foi estudar a restabelecimento da atemoieira (Annona cherimola Mill. x A. squamosa L. cv. 'Thompson') enxertada em atemoieira (A. cherimola Mill. x A. squamosa L. cv. 'Thompson'), araticum-mirim [A. emarginata (Schltdl.) H. Rainer "variedade mirim", araticum-de-terra-fria [A. emarginata (Schltdl.) H. Rainer "variedade terra-fria" e biribá [A. mucosa (Bail.) H. Rainer]. Após a enxertia foram realizadas avaliações das trocas gasosas; de crescimento vegetal; análises da concentração iônica de elementos minerais no tecido foliar e radicular; determinações das concentrações de compostos fenólicos totais e atividade da peroxidase; expressão do gene UGP e atividade enzimática da UDP-glicose pirofosforilase. Os porta-enxertos modularam as trocas gasosas alterando a eficiência de carboxilação e a transpiração. Variações no crescimento e nas concentrações de elementos essenciais em folhas e raízes também foram observadas em função das combinações copa/porta-enxerto. Em relação a atividade da peroxidase, observou-se aumento no porta-enxerto araticum-mirim em relação às demais espécies. Por outro lado, não foram verificadas diferenças nas concentrações de compostos fenólicos nas regiões enxertadas, no entanto tais concentrações foram maiores do que nos péfrancos. A enxertia alterou a expressão do gene UGP, o que indica a possibilidade de maior formação de tecido de parede celular, sendo que a combinação atemoia enxertada ... / Abstract: Grafting is used efficiently for the commercial cultivation of fruit species, because it is necessary to ensure the genetic characteristics of productive species with the use of selected clones. Although grafting is common and widespread technique, mechanisms for compatibility in woody fruit are not well elucidated. Thus, the aim of this thesis was to study of restoring of atemoya (Annona cherimola Mill. x A.squamosa L. cv. 'Thompson') grafted onto atemoya (A. cherimola Mill. x Annona squamosa L. cv. 'Thompson'), araticum-mirim [A. emarginata (Schltdl.) H. Rainer 'variety mirim'], araticum-de-terra-fria [A. emarginata (Schltdl.) H. Rainer 'variety terra-fria'] and biribá [A. mucosa (Bail.) H. Rainer]. After grafting were evaluated gas exchange; plant growth; ionic concentration of mineral elements in the leaf and root tissues; determinations of the concentrations of phenolic compounds and peroxidase activity; UGP gene expression and enzymatic activity of UDP-glucose pyrophosphorylase (UGPase). Rootstocks modulate gas exchange by altering the carboxylation efficiency and transpiration, without, however showed favorable water economy. Changes in growth and concentrations of mineral elements in leaves and roots were also observed as a function of scion/rootstock combinations. In relation to the peroxidase activity, there was an increase in 'araticum-mirim' rootstock in relation to other species. Moreover, there were no differences in the concentrations of phenolic compounds in the grafted union, although these concentrations were higher than in rootstock. Grafting altered UGP gene expression, and the combination atemoya grafted onto 'araticum-de-terra-fria' (previously regarded as compatible combination) showed an increase in gene expression since the early stages after grafting. The results showed that there UGPase enzymatic activity, but there is no difference in this activity between different scion/ rootstock ... / Doutor

Orientador: Ivany Ferraz Marques Valio / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-05T07:52:23Z (GMT). No. of bitstreams: 1 Santos_SandyLiados_D.pdf: 2051849 bytes, checksum: 71014a56afed5c101f1117b77209e2cc (MD5) Previous issue date: 2005 / Resumo: A Mata Santa Genebra é um fragmento isolado de Floresta Atlântica. Por se encontrar muito próximo a áreas urbanas, seu ecossistema está sujeito ao resultado das ações humanas. Devido a constante formação de clareiras em seu interior a floresta torna-se de fundamental importância para o conhecimento da dinâmica destas clareiras, visando sua preservação. O objetivo deste trabalho foi registrar e analisar alguns fatores que pudessem limitar a presença das espécies pioneiras nas clareiras. Para tanto, dados climáticos como irradiância solar, razão V:VE, temperatura e umidade do solo e do ar e precipitação pluviométrica foram registrados durante as estações seca e chuvosa. Também foram registrados dados sobre o banco e a chuva de sementes, a germinação de sementes, o recrutamento de plântulas, o crescimento e a sobrevivência de espécies pioneiras plantadas nas clareiras da MSG. Três clareiras com áreas aproximadas de 82m², 186m² e 660m² foram estudadas. Os mesmos dados foram observados nas três clareiras. No total, 49 espécies de 23 famílias foram registradas. Destas, 21 espécies estiveram presente no estudo do recrutamento, 35 espécies no estudo sobre o banco de sementes e 36 espécies no estudo sobre a chuva de sementes. As famílias mais representativas nos três estudos foram Asteraceae (27%) e Poaceae (14%). Das 49 espécies identificadas, 49% foram nativas, 27% ruderais, 2% exóticas e 22% não foram classificadas. O hábito herbáceo predominou com 49%, seguido pelo arbóreo (20%), arbustivo (12%) e trepadeiras (6%). A dispersão de 43% das espécies foi por anemocoria, 24% por zoocoria, 12% por autocoria e 21% não foram classificadas. Há uma fase da regeneração das clareiras de florestas tropicais onde as lianas predominam e permanecem por vários anos formando um dossel baixo e bastante fechado. A escassez de árvores nas clareiras se deve provavelmente à proliferação rápida das lianas, que reduzem o crescimento de outras plantas e aumentam a mortalidade de árvores. O manejo das lianas nas clareiras necessita de atenção e cuidados, pois, apesar da presença destas reduzir drasticamente a diversidade de espécies vegetais nas clareiras, sua presença é fundamental para a sobrevivência e equilíbrio ecológico, das espécies de animais que habitam nesta mata. Neste estudo à exposição do solo foi feita através do recuo para as margens das clareiras, da massa vegetal das lianas. O plantio de espécies nativas acelera a recuperação das clareiras e exige poucos cuidados quando realizado na estação chuvosa / Abstract: The Mata Santa Genebra (22°49¿45¿S 47°06¿33¿W) is an isolated fragment of the Atlantic Forest. Due to the constant formation of gaps in the interior of the forest it becomes of fundamental importance the knowledge of the dynamics of these gaps for the preservation of the forest. The objectives of this paper were to record and analyze factors which could limit the presence of pioneer species in the gaps. Then, climatic data such as solar irradiance, red: far-red ratio, air and soil temperatures and humidity were recorded during the dry and rainy season, beside pluviometric precipitation. Data were also recorded on seed bank, seed rain, seed germination, recruitment, growth and survival of pioneer species planted in gaps of the Mata Santa Genebra. Three gaps were studied with areas approximately of 82m², 186m² and 660m². Some observed data were very closed in the three gaps. In the three gaps 49 species were identified from 23 families. From that, 21 species were present in the recruitment, 35 in the seed bank and 36 in the seed rain. The most representative families were Asteraceae (27%) and Poaceae (14%). From the 49 identified species 49% were native, 27% were weed, 2% were exotic and 22% unclassified. Herbs were predominant (49%), followed by trees (20%), shrubs (12%) and lianas (6%). The dispersion of 43% of species was by anemocory, 24% by zoocory and 12% by autocory and 21% unclassified. There is a stage of gap regeneration in Tropical Forest where lianas are predominant and remain for many years as a low dense canopy. The rarity of trees in these gaps is probably due to the fast proliferation of lianas that besides reducing growth of other plants increases mortality of trees. The management of lianas in the gaps needs to be made very cautiously. Although their presence causes drastic reduction in the species diversity in the gaps, their presence is of fundamental importance to survival and ecological equilibrium of animals which live in the forest. In this paper some intervention was done in the gaps, in relation to bare soil by moving aside herbs and lianas. Planting local native species accelerates the recovery of gaps and do not require much attention when done during rainy season / Doutorado / Doutor em Biologia Vegetal

Thesis (Ph. D. (Plant Production)) -- University of Limpopo, 2015 / Wild watermelon (Cucumis africanus LF.) and wild cucumber (Cucumis myriocarpus Naude.) are known for their ethnomedicine, ethnopesticide, ethnonematicide and nutritional properties, along with nematode resistance. The two Cucumis species were successfully used as inter-generic seedling rootstocks for watermelon (Citrullus lanatus Thunb.) cultivars, where nematode-resistant genotypes are not available. Also, the two Cucumis species are hardy and resilient to inland South Africa conditions, where temperatures are predicted to increase by 6°C in the year 2030. Seeds in the Cucurbitaceae Family contain high concentration of cucurbitacins, which induce auto-allelopathy that inherently inhibits plant growth and germination. Poor germination and non-uniform stands as a result of seed dormancy are a major challenge in sexual propagation of wild Cucumis species for various potential industries. Generally, true-to-type, uniform and disease-free plants in plant production are asexually-generated through in vitro propagation techniques. This study was therefore, initiated to address seed dormancy and related challenges of sexual propagation in the two wild Cucumis species by determining whether: (1) seed dormancy in C. africanus and C. myiocarpus would be ameliorated to allow for in vitro sexual propagation to establish pathogen-free parent stock, (2) the testa in C. africanus and C. myiocarpus seeds would possess structures, which interfere with imbibition and movement of water to the endosperm, (3) all organs of C. africanus and C. myriocarpus would be suitable for in vitro propagation, (4) suitable potting medium for in vitro propagated plantlets of C. africanus and C. myriocarpus would be available for acclimatisation of plantlets and (5) in vitro-produced xxviii plantlets from nematode-resistant C. africanus and C. myriocarpus would retain their resistance to Meloidogyne incognita race 2 under greenhouse conditions. In vitro and ex vitro experiments were conducted to achieve the stated objectives, with treatments in the laboratory and the greenhouse being arranged in completely randomised and randomised complete block designs, respectively. Validity was primarily ensured through the use of factorial trials, while the reliability of data was ensured by using appropriate levels of statistical significance. Leaching alone in C. africanus improved germination, while in C. myriocarpus this treatment had no effect on germination. The optimum leaching time in leached-control seeds of C. africanus was achieved at 7.1 h, with a 25-day mean germination time (MGT) and 52% optimum germination percentage (GP). In the two Cucumis species, the combined effect of leaching seeds in running tapwater and physical scarification of seeds at the chalaza region escalated germination in both Cucumis species, suggesting that both chemical and physical seed dormancies were involved. In C. africanus, cucurbitacin B (C32H48O8) was deposited exogenously to the testa, whereas in C. myriocarpus cucurbitacin A [cucumin (C27H4009) and leptodermin (C27H3808)], was deposited endogenously to the testa. The optimum leaching time in leached-scarified (LS) seeds of C. africanus was achieved at 5.7 h, with at least 40-day MGT and 89% optimum GP. In contrast, in C. myriocarpus LS seeds had the optimum leaching time of 6.3 h, with at least 41 days MGT and 93% optimum GP. Field emission SEM confirmed that there were two “water-gaps”, one at the micropylar region (hilum end) and the other at chalaza region (abaxial end) of seeds in both Cucumis species. Five distinct testa layers in seeds of C. myriocarpus were observed, namely, (i) epidermis, (ii) hypodermis, (iii) sclerenchyma, (iv) aerenchyma xxix and (v) chlorenchyma. In contrast, C. africanus seeds did not have the hypodermis between the micropylar and chalaza regions, but was present around both regions, which may provide some explanation of sporadic germination in non-leached and non-scarified seeds in this Cucumis species. The most suitable plant propagules for in vitro mass propagation of the two Cucumis species were nodal and apical buds. The optimum PGRs for shoot regeneration using both propagules in C. africanus and C. myriocarpus were at 0.80 and 0.35 μM 6-benzyladeninepurine (BAP), respectively. In contrast, the largest number of roots was regenerated at 0.31 and 0.44 μM indole-3-butyric acid (IBA) for C. africanus and C. myriocarpus, respectively. In vitro-produced plantlets were successfully acclimatised to ex vitro conditions, with sand + compost potting medium being the most suitable growing medium for weaning both Cucumis species. The in vitro-produced plantlets retained their resistance to M. incognita race 2. In conclusion, seeds of C. africanus and C. myriocarpus are structurally and chemically different, with strong evidence of chemical and physical dormancies. Structurally, C. myriocarpus seeds consist of five layers, four lignified and one non-lignified, whereas those of C. africanus have four layers, three lignified and one non-lignified. Evidence suggested that in C. africanus seeds, allelochemicals were primarily deposited outside the testa, whereas in C. myriocarpus they were deposited within the testa. The identified seed dormancies could successfully be ameliorated through combining leaching and scarification in both Cucumis species. The developed in vitro propagation protocols accord the two Cucumis species the potential for use as future crops in the context of climate-smart agriculture and research. / Flemish Interuniversity Council (VLIR)

No description available.

No description available.

Temperate deciduous fruit trees have poor and delayed bud break when they are grown in warm areas. The delay is due to a lack of the chilling which is required to break bud endodormancy. Bud endodormancy can be overcome in some species by treatments such as H₂CN₂, heat, and bud scale removal. We tested the effects of chilling, H₂CN₂, heat, and removing scales on bud break of floral and vegetative buds of 'Tifblue' rabbiteye blueberry (Vaccinium ashei Reade). Hydrogen cyanamide was effective in promoting floral bud break of 'Tifblue' only on whole plants, at chilling exposures between 300 to 500 hours. However, vegetative bud break was increased by H₂CN₂ at a wider range of ~hilling exposures than floral buds in both whole plants and cut shoots. Optimum vegetative bud break was induced by H₂CN₂ at 125 and 250 mM for whole plants and cut shoots, respectively. Hydrogen cyanamide was highly phytotoxic to floral buds compared to vegetative buds. However, floral buds of whole plants became tolerant to H₂CN₂ as chilling increased. Injury to vegetative buds was significant only at 500 mM H₂CN₂. The chilling requirement for 'Tifblue' floral buds of whole plants was 500 hours. In contrast, vegetative buds did not have a significant relationship with chilling exposure in either cut shoots or whole plants. Heat treatment was effective in promoting floral bud break of cut shoots only at 190 chilling hours at 30 minutes heat exposure. Heat (47°C) for I hr was effective in promoting vegetative bud break, but the effectiveness varied with chilling level and depended on time of heat exposure. Bud scale removal did not promote floral bud break, but increased vegetative bud break, although not significant compared to control. Finally, we discovered that vegetative buds remained dormant even after they had received more than adequate chilling. However, both H₂CN₂ treatment and floral bud removal resulted in increased vegetative bud break, although the effect of H₂CN₂ was less than floral bud removal. This suggests that vegetative buds were inhibited by floral buds and that H₂CN₂ could partially overcome this paradormant effect. / Master of Science

O setor de produção de coco é atingido por vários problemas que afetam sua produtividade especialmente o uso difundido de plantas sem seleção devido a características intrínsecas da cultura que dificultam a seleção de cultivares com características superiores. O uso eficiente dos recursos genéticos do coco tem encontrado dificuldades na coleta e troca de germoplasma. A cultura de tecidos tem por finalidade viabilizar a troca segura de germoplasma e facilitar o desenvolvimento de variedades produtivas em um programa de melhoramento genético, porém a regeneração de plantas através de técnicas in vitro tem apresentado dificuldades adicionais no estabelecimento de protocolos viáveis. O presente trabalho teve por objetivo estabelecer um protocolo viável para a regeneração de embriões zigóticos para ser utilizado em programas de melhoramento genético e para o transporte seguro de germoplasma, testando diferentes meios básicos de cultura, presença de reguladores vegetais, concentração de sacarose e fontes de aminoácidos. A regeneração de embriões foi mais efetiva em meio de cultura Y3 (Eeuwens, 1976) com concentração de Fe2SO4 41,7 mg.L -1 e Na2EDTA 55,8 mg.L -1 na presença de glicina e ausência de mio-inositol, contendo carvão ativado. A presença de reguladores vegetais e a caseína hidrolisada foram limitantes inclusive inibindo a germinação. A presença de altas concentrações de sacarose (60 g/L) mostrou melhores resultados. / The sector of coconut production is reached by several problems that affect his productivity especially the spread use of plants without selection due to intrinsic characteristics of the culture that difficult the selections for cultivars whit superiors characteristics. The efficient use of the genetic resources of the coconut has been having difficulties in collecting and germplasm exchange. The tissue culture has for purpose to make possible the safety change of germplasm and to facilitate the development of productive varieties in a program of genetic improvement; however the regeneration of plants through in vitro techniques has been presenting additional difficulties in the establishment of viable protocols. The present work had for objective to establish a viable protocol for the regeneration of coconut zigotic embryos to be used in programs of genetic improvement and for the safe movement of germplasm, testing different basic media of tissue culture, presence of growth regulators, sucrose concentration and sources of amino acids. The regeneration of embryos was more effective in Y3 (Eeuwens, 1976) media with concentration of Fe2SO4 41,7 mg.L -1 and Na2EDTA 55,8 mg.L -1 whit presence of glycine and absence of meso-inositol, containing activated charcoal. The growth regulators and hydrolysate casein presence even inhibited germination. The presence of high sucrose concentrations (60 g/L) showed better results.

Thesis ( PhD. (Biotechnology )) --University of Limpopo, 2005 / The marula tree (Sclerocarya birrea subsp. caffra), an indigenous, multipurpose, drought tolerant tree of Africa harbors great economic potential. Acceptance of marula-derived products internationally will directly increase the demand for marula resource. Rapid multiplication of marula trees of superior quality forms the basis of sustainable export growth. In vitro propagation and genetic improvement offer the opportunity for accelerated multiplication of selected tree material as well as to dramatically increase production, quality and efficiencies. The objectives of the study were therefore to develop a protocol for in vitro multiplication of marula and to determine the feasibility of Agrobacterium-mediated transformation of the marula tree. Nodal sections with axillary bud (s) were cultured on Murashige and Skoog (MS) medium supplemented with 4.8μM BA and 2.4μM KN and 0.1% polyvinylpyrrolidone (PVP) to obtain on average 2.5 microshoots per responding explant. The proliferated microshoots were elongated on MS medium supplemented with 1.2μM BA and 1.0μM KN. Elongated microshoots were rooted in MS medium at half salts strength supplemented with 10μM IBA and 0.3% activated charcoal (AC). On average 82% of the shoots rooted. Survival of acclimatized plantlets was 90%. RAPD analysis confirmed intraclonal genetic stability between parent plants and their clones within the limits of the technique.Nodal sections cocultivated with Agrobacterium tumefaciens for 3 days on MS multiplication medium supplemented with 100μM acetosyringone resulted on average in transient expression of 52.5% of the explants with 1.6 blue stained zones per explant. Cocultivated explants on MS selection medium containing 300mgl-1 kanamycin resulted in 1.5% chimeric putative transgenic shoots. This is the first report on the micropropagation and genetic transformation of marula, Sclerocarya birrea subsp caffra. / South Africa’s National Research Foundation Institutional Research Development Program (NRF-IRDP)

The effect of steady shear stress on somatic embryos were investigated in a flow chamber and evaluated at different time intervals using microscopy technique. The development of meristematic cell clusters, i.e. the immature embryos, into a polarized somatic embryo, and the effect on the localization of the suspensor cells that form during development of the immature embryos, were studied as a function of shear stresses. With the distribution and growth rate of the meristematic and suspensor cells, the effect of stress on the embryo development was established. Furthermore, the effect of shear stress on the cells at molecular level, the reaction of integrin-like proteins, the production of reactive oxygen species and the pore size of the cell walls involved in the shear stress responses, were investigated with molecular techniques. In general, shear stress inhibits meristematic cells growth. Meristematic cells grow fastest at shear rate of 86 s-1 among all the tested shear stress conditions. By combining the results of meristematic cells growth and suspensor cells formation, it suggests that there is a critical shear rate between 86 and 140 s-1, at which no suspensor cells form. The unidirectional flow with different shear stresses helps the polarized growth and the unidirectional alignment of suspensor cells. Reactive oxygen species and integrin-like protein are detected in the stressed cells as cellular responses to shear stresses. By monitoring the pore size and uptake time of cells to macromolecules with solute-exclusive experiments, it suggests that the stressed cells expedite the response to plasmolyzing components that are used to induce maturation treatment thus affect the response to maturation stimuli.