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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.
31

Flower abscission in potted Plectranthus.

Rice, Laura Jane. 07 November 2013 (has links)
Transport and post-harvest handling of flowers both cut and potted is one of the greatest challenges in the horticulture industry (REDMAN et al., 2002). Ethylene-induced flower abscission is responsible for the loss of crops (KIM et al., 2007). Flower abscission is greater when plants are transported (ABEBIE et al., 2005). This limits the sale of flowers and potted plants to areas close to the site of production and prevents export opportunities. South Africa is home to many spectacular species with great horticultural potential (RICE et al., 2011). Unfortunately however, development of a number of these species for export is difficult due to transport-induced flower abscission. Transport-induced flower abscission is a problem experienced by Dr Gert Brits, a breeder of Plectranthus in Stellenbosch in South Africa. In this study a number of Dr Brits’s Plectranthus varieties were used as model plants to understand the process of transport-induced flower abscission and develop a protocol for the prevention of such abscission. Flow cytometry was used to determine the ploidy levels of each of the varieties. It was important to be aware of this during the experiments as varieties with different ploidy levels have been reported to behave differently under stressful environmental conditions. Of the eight varieties examined, three were diploid (2n), one was triploid (3n), three were tetraploid (4n) and one was a mixopliod (2n/4n) variety. To determine the effects of packaging plants during transport and the effects of darkness on flower abscission, plants were packaged into perspex chambers and kept either in a 16 h photoperiod or in darkness for 96 h. Every 24 h the number of open and unopened flowers that had abscised was recorded. Both packaging and darkness increased flower abscission of open and unopened flowers in all eight varieties. Four varieties preferentially abscised open flowers; while the remaining four preferentially abscised unopened flowers. All eight varieties were exposed to different concentrations of ethylene (0, 0.1, 0.25 0.5, 1 and 2 μll-1) to determine their level of ethylene sensitivity. All of the Plectranthus varieties were determined to be extremely sensitive to ethylene. With 100% flower abscission occurring within 24 h at 1 and 2 μll-1 in all varieties. In order to determine what internal changes were causing this increase in flower abscission under these conditions, the changes in the expression of key ethylene biosynthetic enzymes, cytokinin content and carbohydrates in the flowers were examined. ACS and ACO are the two key enzymes in the ethylene biosynthetic pathway (JOHNSON & ECKER, 1998). Changes in the levels of mRNAs coding for these two enzymes were examined when plants were packaged and put into the dark. In general there was an upregulation of the ethylene biosynthetic pathway and in turn this may have increased ethylene production by the plants under simulated transport conditions. However, the changes were not large enough to be solely responsible for the increased flower abscission observed under simulated transport conditions. The concentrations of 43 cytokinins were measured in pedicle tissue from plants which had been kept in the dark for 0, 24, 48, 72 and 96 h. Of the 43 cytokinins measured 21 were below the level of detection. Concentrations for the remaining 22 cytokinins at each of the time points were examined and it was found that in general cytokinin concentrations increase when plants are packaged and put into the dark. DHZ-type cytokinins remained stable during the 96 h continuous dark monitoring period, with most of the changes observed in the tZ and iP types. Peaks in cytokinin concentrations are often followed by an increase in flower abscission, indicating that an increase in cytokinin concentrations may be one of the factors causing the increase in transport-induced flower abscission. Only glucose and fructose were detected in peduncle tissue. Changes in glucose and fructose over 24 h in the greenhouse and over 0, 24, 48, 72 and 96 h in simulated transport conditions were measured. During the day, glucose and fructose levels increased towards the afternoon and evening and decreased in the early morning. This is consistent with studies conducted on other species (ALONI et al., 1996). When plants were put into the dark, glucose and fructose levels increased slightly at 24 h and then decreased to levels similar to those measured in control plants. Although there were changes in glucose and fructose level in simulated transport conditions, they were very slight and it is unlikely that these changes are not responsible for the transport-induced flower abscission. These results suggest that the observed transport-induced flower abscission is the result of increased cytokinin concentrations and expression of ACO and ACS genes when plants are packaged and put into the dark. These changes in turn cause an increase in ethylene production by the plants, and the build-up of ethylene in the transport container causes flowers to abscise. Ethylene perception by the plant is the step which could be targeted to prevent flower abscission. A number of ethylene antagonists block the ethylene receptors in the plant and in so doing prevent the receptors from binding ethylene and transducing the abscission signal. 1-MCP isone such ethylene antagonist. To test whether 1-MCP could be used for the prevention of flower abscission in Plectranthus, plants were placed in sealed perspex chambers in the light and in the dark and treated with 100 nll-1 1-MCP for a single 6 h treatment, or for 6 h every day prior to continuous exposure to ethylene. 1-MCP treatment greatly reduced ethylene- and transport-induced flower abscission when plants were treated continuously, but reduced flower abscission for the first 24 h when pre-treated with a single 6 h exposure to 1-MCP.Transport-induced flower abscission in Plectranthus is the result of exposure to ethylene. The increase in ethylene production by the plants in transport conditions is likely due to an upregulation of the ethylene biosynthetic pathway and an increase in cytokinin concentrations or movement in the pedicle tissue. This transport-induced flower abscission can be prevented by continuous treatment with 100 nll-1 1-MCP during the transport period. By using 1-MCP plants can be transported for up to 4 d and the opportunity for export is made possible. / Thesis (Ph.D.)-University of KwaZulu-Natal, Piertermaritzburg, 2013.
32

The integration of the South African floriculture industry into the global market / M. van der Walt

Matthee, Marianne January 2004 (has links)
As a result of globalisation, firms across both developed and developing countries are experiencing increased competition. Globalisation has both positive and negative consequences for firms, and the net effect may depend on the manner in which the country where a firm is located participates in the global market. Both the global commodity chain (GCC) and global value chain (GVC) approaches assess countries' integration (either successfully or unsuccessfully) into the global market. The international floriculture industry is one that is constantly changing and has a highly competitive environment. These challenges require that its participants be successfully integrated into the market and constantly improve their competitive positions. The South African floriculture industry has become more integrated into the global market since it opened up its economy in 1994. Both revenue and employment in this industry have increased since then. However, South Africa remains fairly uncompetitive compared with its African counterparts. The overall aim of this study was to assess the impact of the global floriculture industry on both the competitiveness of the South African floriculture industry and its integration into the global market. The GCC and GVC approaches were used in this assessment. The literature study provided background to these approaches in the context of globalisation. A detailed description was further given to the attributes and challenges of the global floriculture arena, together with a delineation of the South African floriculture industry. The empirical study was conducted through a mail-based questionnaire, which was mailed to the members of the South African Flower Export Council. The response rate of the survey was 59 per cent and can be considered high for a mail-based questionnaire. The responses were analysed according to the elements of the GVC and GCC approaches. This enabled an analysis of the global chains that the exporters form part of. Hence, it identified the role players and variables within these chains that influence the ultimate income of the floriculture industry. From the empirical findings it was possible to determine the South African export floriculture industry's strengths and weaknesses. The conclusion drawn was that the South African floriculture industry functions successful internationally, according to the elements of the GCC and GVC approaches. However, the industry does not participate to its full potential in the global market and lacks competitiveness. These findings supported the assumptions in the literature study. Once the South African floriculture exporters become more export-oriented (i.e. shift their focus from the domestic to the international market), the industry's competitiveness will enhance. Becoming further integrated into the global market by increasing both the volumes and values of their exports can do this. Ultimately the exporters will be able to move into better and more competitive global chains (i.e. export more directly). / Thesis (M.Com. (International Commerce))--North-West University, Potchefstroom Campus, 2005.
33

Effect of pruning on economic biomass production of Protea cv. Carnival

Gerber, Audrey I. (Audrey Inga) 12 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 1994. / Some digitised pages may appear illegible due to the condition of the Microfiche / ENGLISH ABSTRACT: Many Proreaceae species indigenous to South Africa have potential as cutflower crops. Commercial production of proteas for expurt, mainly to Europe, must emphasise quality of flowers and time of production. Good export quality flowers have stems longer than 50cm and unblemished flowers. Cut-flower proteas are in greater demand and command better prices during the European winter (September to May, Southern hemisphere), when competition from flowers grown in Europe is less. Both quality and time of harvest can be manipulated by pruning techniques. Protea cv. Carnival (a natural hybrid, possibly between P. neriifolia and P. compacta) produces flowers in late summer, from February through to May. Picking flowers or pruning shoots of Proteo cv. Carnival entails removing the terminal portion of shoots with heading cuts to leave on the plant short stumps, known as bearers. Lateral shoots arising from axillary buds on bearers elongate by successive growth flushes until flowers are initiated terminally. The characteristics of the shoot determine whether or not flower initiation will take place, and will affect the quality of the resulting flower. Plants were pruned to produce bearers of different length and diameter. The characteristics of shoots arising from different bearers were recordea. Thick bearers of length 20-25cm produced the most shoots, and the longest shoots. Plants producing flowers biennially, rather than ann'Jally, produced thicker bearers, which, in turn, lead to production of better quality shoots arising from the bearers in the following season. Changing the time of pruning changed both the flowering cycle and the biomass allocation of Prorea cv. Carnival. Plants of Profea cv. Carnival were pruned on six different dates in 1991. Pruning in March, April or May, 1991, resulted in an annual flowering cycle. Less than 40% of the fresh mass produced in 1993 was reproductive, of which approximately 5% had stems long enough for export. The 1994 annual harvest was of s:milar size and quality as the 1993 annual harvest. Pruning in July, August or September, 1991, resulted in a biennial cycle of flowering. No flowers were produced in 1992, and a large crop was harvested in 1993. In 1993 lip to 70% of the fresh mass produced was reproductive, of which approximately 80% had stems long enough for export. Plants were pruned shortly after flowering in 1993, and the biennial cycle was replaced by an alternate flowering cycle, with a large crop being followed by a smaller crop. The large harvest in 1993 was significantly earlier than normal, but the small crop produced in 1994 was later. The harvest in 1994 from plants with an alternate flowering cycle was similar in size to the 1994 harvest from plants floweting annually, but flower stems were longer. / AFRIKAANSE OPSOMMING: Heelwat inheemse Proteaceae spesies besit die vereiste eienskappe om as snyblomr.-le verhanctci te wod. Indien proteas kommersieel verbou sou word vir uitvoer moet die klem val op gehalte van blomme en die tyd van produksie. Goeie gehalte uitvoer blomme moet steellengte van langer as 50cm en perfek gevormde blomme besit. Daar is 'n groter aanvraag na kommersieel verboude proteas gedurende die Europese winter (September tot Mei, suidelike halfrond) en beter pryse word derhalwe ook dan verkry. Beide gehalte en die oes periode kan gemanipuleer word deur snoeitegnieke. Wanneer blomme gepluk word of lote gesnoei word van Profea cv. Carnival (waarskynlik 'n kruising tussen P. compacta x P. neriifolia) word die terminale gedeelte van die loot teruggesny. Die oorblywende gedeelte bestaan uit kort stompe wat bekend staan as draers. Laterale lote afkomstig van okselknoppe op draers verleng totdat 'n blom terminaal ontwikkel. Die eienskappe van die loot bepaal of 'n blom inisieer sal word of nie, en sal ook die gehalte van die gevormde blom beinvloed. Protea plante was gesnoei om draers van verkillende lengtes en deursnee te produseer. Die eienkappe van lote afkomstig van die verskillende tipe draers was gemeet. Dik ..draers van lengte 20-25cm het die meeste asook die langste lote geproduseer. Plante wat twee-jaarliks, in teenstelling met jaarliks, geblom het, het dikker draers geproduseer en ook gelei tot produksie van beter gehalte lote in die opeenvolgende seisoen. Die verandering in die tyd van snoei het beide die blom siklus en die biomassa verspreiding beinvloed. Plante van Protea cv. Carnival was up 6 verskillende datums in 1991 gesnoei. Snoei in Maart, April of Mei, 1991, het 'n jaarlikse blom siklus veroorsaak. Minder as 40% van die vars massa geproduseer in 1993 was reproduktief, waarvan 5% steellengte lank genoeg vir uitvoer gehad hel. Die 1994 jaarlikse oes was van dieselfde grootte en gehalte as die van 1993. Snoei in Julie, Augustus of September, 1991, het egter 'n twee-jaarlikse blom siklus veroorsaak. Geen blomme was in 1992 geproduseer nie, maar die oes in 1993 was heelwat groter as die jaarlikse oeste. In 1993 was to 70% van die vars massa geproduseer, reproduktief, waarvan 80% steellengte lank genoeg vir uitvoer gehad het. Die twee-jaarlikse blom siklus het 'n vroeer oes in 1993 veroorsaak, maar 'n later oes in 1994. Die twee-jaarlikse oes in 1994 was van dieseifde grootte as die jaarlikse oes in 1994, maar die blomstele was langer.
34

Características dos substratos no desenvolvimento, nutrição e produção de gérbera (Gerbera jamesonii) em vaso /

Ludwig, Fernanda, 1979- January 2010 (has links)
Resumo : O substrato para plantas exerce grande influência na produção de flores e plantas ornamentais, em especial as de cultivo em vaso, onde há restrição do volume disponível para o crescimento das raízes. O manuseio de substratos, as proporções e tipos de misturas interferem nas suas características físicas e químicas, devendo o produtor conhecer o material a ser utilizado para evitar perdas. A presente pesquisa foi desenvolvida com o objetivo de avaliar o efeito de substratos com características químicas e físicas diferenciadas, no desenvolvimento, nutrição e produção de cultivares de Gerbera jamesonii produzidas em vaso. O experimento foi realizado em casa de vegetação no DRN/Ciência do Solo da FCA/UNESP no município de Botucatu/SP, de agosto a outubro de 2008. O delineamento experimental foi em blocos casualizados, empregando o esquema fatorial 5 x 2 (5 substratos e 2 cultivares), em 4 blocos e 12 plantas por parcela. Os substratos foram caracterizados fisicamente quanto à densidade, retenção de água e granulometria, e quimicamente quanto à condutividade elétrica, pH, capacidade de troca de cátions (CTC), macronutrientes e micronutrientes. Foram utilizadas cultivares de gérbera pertencentes a serie 'Dark eyes' da empresa Sakata®, sendo Cherry e Red. Efetuou-se o manejo da condutividade elétrica da solução do substrato, mantendo-a em 2,0 dS m-1 no período vegetativo e 2,5 dS m-1 no período reprodutivo, com o uso do método 'pourthru'. Durante o desenvolvimento da cultura foram avaliados a condutividade elétrica e pH da solução do substrato, o número de folhas, o diâmetro da planta, a área foliar, a fitomassa seca, o teor e acúmulo dos macronutrientes e micronutrientes, o teor de nitrato e potássio na solução do substrato, a razão de área foliar a taxa de crescimento relativo e a taxa de assimilação líquida. Ao final do período vegetativo...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The substrate exerts great influence on the flowers and ornamental plants production, especially those growing in pots, where there is restriction on the volume available for root growth. The handling of substrates, the proportions and types of mixtures interfere in physical and chemical characteristics and the knowledge of the material is important to avoid losses. This research was developed to evaluate the effect of substrates with different chemical and physical characteristics in the development, nutrition and production of Gerbera jamesonii cultivars grown in pots. The experiment was carried out in a greenhouse from August to October 2008 at DRN/Soil Science, FCA/UNESP, Botucatu (SP), Brazil. Experimental design was in randomized blocks, in factorial arrangement 5x2 (5 substrates and 2 cultivars), with 4 replicates and 12 plants per plot. The substrates were characterized physically as the bulk density, water retention and granulometry, and chemically on the electrical conductivity, pH, cation exchange capacity (CEC), macronutrients and micronutrients. Seedling of gerbera cultivars Cherry and Red (Sakata®) of the 'Dark eyes' series were used in the experiment. The levels of electrical conductivity of the substrates were monitored in the solution of root zone of the plants through the extraction of the solution by 'pourthru' method, keeping it at 2.0 dS m-1 in the vegetative period and 2.5 dS m-1 in the reproductive period. During the development of the culture were assessed: electrical conductivity, pH of substrate solution, leaf number, plant diameter, leaf area, dry matter, content and accumulation of macronutrients and micronutrients, nitrate and potassium in the sap and the substrate solution and green intensity leaf, the ratio of leaf area... (Complete abstract click electronic access below) / Orientador: Dirceu Maximino Fernandes / Coorientador: Roberto Lyra Villas Bôas / Banca: Hélio Grassi Filho / Banca: Carmen Silvia Fernandes Boaro / Banca: Ana Maria Conte e Castro / Banca: Simone da Costa Mello / Doutor
35

Cultivo de Heliconia golden torch sob diferentes fontes e doses de silício / Culture of Heliconia golden torch under different sources and doses of silicon

Paulino, Ademar da Silva 28 February 2012 (has links)
Growing heliconias is an activity that has gained prominence in recent decades, as well as the use of silicate fertilizers that with the advancement of research, has increased its demand. The objective of this study was to test different sources and doses of silicate fertilizers in the cultivation of Heliconia Golden Torch to assess aspects of quality of production and post-harvest flowers. The experiment was arranged in randomized blocks with nine treatments and four replications, with three sources: ash from sugar cane bagasse, MB-4 and Rocksil® and three doses of SiO2: 0, 400 and 800 kg ha-1 of respective sources. The installation of the trial took place in the agricultural sector of the Federal Institute of Alagoas - Campus Satuba. The results showed that the number of inflorescences increased with the source Rocksil®, length of bracts was increased with interaction between ash and dose 400 kg ha-1, mass loss on the eighth day post-harvest was lower with the interaction between Rocksil® and dose 400 kg ha-1, burning of bract on the eighth day post-harvest was lowest with source Rocksil® at a dose 800 kg ha-1 and Si content in the soil to a depth of 0-0.20 m increased with increasing dose of silicon. As for the variables: length of flower stalks and, mass of flower stalks on the day of harvest and on the eighth day after harvest, content of silicon leaf and soil to a depth of 0.20-0.40 m there was no significant difference between treatments by grouping test of Scott-Knott medium. The silicon fertilization increased production and post-harvest quality, especially if the source Rocksil® at a dose 800 kg ha-1. / O cultivo de heliconias é uma atividade que vem ganhando destaque nas últimas décadas, bem como, o uso de adubos silicatados que, com o avanço das pesquisas, tem sua demanda aumentada. O objetivo deste trabalho foi testar diferentes fontes e doses de adubos contendo silício no cultivo de heliconia Golden Torch para de avaliar aspectos de produção e qualidade de flores no pós-colheita. O experimento foi montado em esquema fatorial 3 x 3 com quatro repetições, sendo três fontes de silício: cinza do bagaço da cana-de-açúcar, MB-4 e Rocksil® e três doses de SiO2: 0, 400 e 800 kg ha-1 das respectivas fontes. A instalação da pesquisa se deu no setor de agricultura do Instituto Federal de Alagoas Campus Satuba. Os resultados obtidos demonstraram que o número de inflorescências cresceu com a fonte Rocksil®, comprimento de brácteas foi maior com interação entre cinza e a dose 400 kg ha-1, perda de massa ao oitavo dia pós-colheita foi menor com a interação entre Rocksil® e a dose 400 kg ha-1, queima de bráctea ao oitavo dia pós-colheita teve menor valor com a fonte Rocksil® na dose 800 kg ha-1 e o teor de Si no solo à profundidade de 0-0,20 m cresceu com o aumento da dose de silício. Já para as variáveis: comprimento de hastes florais, massa de hastes florais no dia da colheita e no oitavo dia após a colheita, teor de silício foliar e no solo à profundidade de 0,20-0,40 m não houve diferença significativa entre os tratamentos pelo teste de agrupamento de médias de Scott-Knott. A adubação com silício aumentou a produtividade e a qualidade pós-colheita, destacando-se a fonte Rocksil® na dose 800 kg ha-1.
36

Doses de nitrogênio no desenvolvimento de girassol ornamental (Helianthus annuus L.) de vaso

Braga, Camila de Lima [UNESP] 31 August 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-08-31Bitstream added on 2014-06-13T20:54:57Z : No. of bitstreams: 1 braga_cl_me_botfca.pdf: 428780 bytes, checksum: 63f80d4298347937b7c43899cc5ea86d (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Objetivou-se avaliar o efeito da aplicação de doses de adubo nitrogenado no desenvolvimento, nutrição e durabilidade de girassol ornamental e diminuição da senescência das folhas mais velhas. O experimento foi conduzido no Departamento de Recursos Naturais - Ciência do Solo, Fazenda Experimental Lageado, pertencente à FCA, UNESP, Campus de Botucatu – SP, em casa de vegetação, no período compreendido de 21 de agosto a 22 de outubro de 2008. Adotou-se o delineamento em blocos casualizados, com quatro doses de nitrogênio (75%, 100%, 125% de 150%), utilizando 100 % como referência a dose de N aplicada pelo produtor (correspondente a 0,035 g L-1 na fase vegetativa e 1,66 g L-1 na fase reprodutiva), tendo como fonte, o nitrato de amônio. Foram utilizadas sementes de girassol ornamental cultivar ‘Sunflower F1 Sumbrite Supreme’ da SAKATA®, semeadas em bandejas com 128 células, posteriormente transplantadas em vasos de plástico número 15, com capacidade para 1,3 L, preenchidas com substrato formulado. Avaliaram-se semanalmente a altura, número de folhas, diâmetro de haste, diâmetro de planta, intensidade de cor verde, além do pH e condutividade elétrica da solução lixiviada. A cada quinze dias realizaram-se coletas de plantas para análise de crescimento com avaliações da área foliar, massa seca total (transformados em dados fisiológicos de taxa de crescimento relativo, taxa assimilatória líquida e razão de área foliar) e teor e acúmulo total de nitrogênio nas folhas sadias, folhas senescentes, hastes e inflorescências. No ponto de comercialização foram avaliados o teor e acúmulo de N-amônio, N-nitrato, macronutrientes (P, K, Ca, Mg e S) e micronutrientes (B, Cu, Fe, Mn e Zn) nas folhas sadias, folhas senescentes, hastes e inflorescências. A precocidade da produção e abertura floral através do diâmetro de capítulo e do disco e das plantas... / This work aimed to evaluate the effect of nitrogen fertilizer application, at different levels, on ornamental sunflower development, nutrition and durability, besides the decrease in the senescence of older leaves. The experiment was carried out between August 21 and October 22, 2008, in a greenhouse from the Department of Natural Resources – Soil Science, Lageado Experimental Farm, Agronomical Sciences College, São Paulo State University, Botucatu Campus, São Paulo State, Brazil. Experimental design was in randomized blocks, with four nitrogen levels (75%, 100%, 125%, and 150%), of which 100% represents the N level sprayed by the producer (corresponding to 0.035 g L-1 and 1.66 g L-1 in the vegetative and reproductive phases, respectively), and ammonium nitrate was used as source. Seeds from ornamental sunflower cultivar ‘Sunflower F1 Sumbrite Supreme’ (SAKATA®) were sown into trays containing 128 cells and later transplanted to plastic pots number 15, 1.3L-capacity, filled with formulated substratum. Height, leaf number, stem diameter, plant diameter, green color intensity, besides pH and electrical conductivity of the leached solution, were weekly evaluated. Every fifteen days, plants were harvested for growth analysis, including evaluations of leaf area, total dry matter (which were transformed into physiological data regarding relative growth rate, net assimilation rate and leaf area ratio), besides nitrogen level and total accumulation in healthy and senescent leaves, stems and inflorescences. In the commercialization stage, the level and the accumulation of N-ammonium, N-nitrate, macronutrients (P, K, Ca, Mg, and S) and micronutrients (B, Cu, Fe, Mn, and Zn) were evaluated in healthy and senescent leaves, stems and inflorescences. Production precocity and flower opening were evaluated through capitulum, disc and plant diameter after the commercialization stage... (Complete abstract click electronic access below)
37

Características dos substratos no desenvolvimento, nutrição e produção de gérbera (Gerbera jamesonii) em vaso

Ludwig, Fernanda [UNESP] 07 May 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-05-07Bitstream added on 2014-06-13T21:04:21Z : No. of bitstreams: 1 ludwig_f_dr_botfca.pdf: 1475372 bytes, checksum: 58b34b6ccf7b93fc7d2a9708f85b4805 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O substrato para plantas exerce grande influência na produção de flores e plantas ornamentais, em especial as de cultivo em vaso, onde há restrição do volume disponível para o crescimento das raízes. O manuseio de substratos, as proporções e tipos de misturas interferem nas suas características físicas e químicas, devendo o produtor conhecer o material a ser utilizado para evitar perdas. A presente pesquisa foi desenvolvida com o objetivo de avaliar o efeito de substratos com características químicas e físicas diferenciadas, no desenvolvimento, nutrição e produção de cultivares de Gerbera jamesonii produzidas em vaso. O experimento foi realizado em casa de vegetação no DRN/Ciência do Solo da FCA/UNESP no município de Botucatu/SP, de agosto a outubro de 2008. O delineamento experimental foi em blocos casualizados, empregando o esquema fatorial 5 x 2 (5 substratos e 2 cultivares), em 4 blocos e 12 plantas por parcela. Os substratos foram caracterizados fisicamente quanto à densidade, retenção de água e granulometria, e quimicamente quanto à condutividade elétrica, pH, capacidade de troca de cátions (CTC), macronutrientes e micronutrientes. Foram utilizadas cultivares de gérbera pertencentes a serie ‘Dark eyes’ da empresa Sakata®, sendo Cherry e Red. Efetuou-se o manejo da condutividade elétrica da solução do substrato, mantendo-a em 2,0 dS m-1 no período vegetativo e 2,5 dS m-1 no período reprodutivo, com o uso do método ‘pourthru’. Durante o desenvolvimento da cultura foram avaliados a condutividade elétrica e pH da solução do substrato, o número de folhas, o diâmetro da planta, a área foliar, a fitomassa seca, o teor e acúmulo dos macronutrientes e micronutrientes, o teor de nitrato e potássio na solução do substrato, a razão de área foliar a taxa de crescimento relativo e a taxa de assimilação líquida. Ao final do período vegetativo... / The substrate exerts great influence on the flowers and ornamental plants production, especially those growing in pots, where there is restriction on the volume available for root growth. The handling of substrates, the proportions and types of mixtures interfere in physical and chemical characteristics and the knowledge of the material is important to avoid losses. This research was developed to evaluate the effect of substrates with different chemical and physical characteristics in the development, nutrition and production of Gerbera jamesonii cultivars grown in pots. The experiment was carried out in a greenhouse from August to October 2008 at DRN/Soil Science, FCA/UNESP, Botucatu (SP), Brazil. Experimental design was in randomized blocks, in factorial arrangement 5x2 (5 substrates and 2 cultivars), with 4 replicates and 12 plants per plot. The substrates were characterized physically as the bulk density, water retention and granulometry, and chemically on the electrical conductivity, pH, cation exchange capacity (CEC), macronutrients and micronutrients. Seedling of gerbera cultivars Cherry and Red (Sakata®) of the ‘Dark eyes’ series were used in the experiment. The levels of electrical conductivity of the substrates were monitored in the solution of root zone of the plants through the extraction of the solution by ‘pourthru’ method, keeping it at 2.0 dS m-1 in the vegetative period and 2.5 dS m-1 in the reproductive period. During the development of the culture were assessed: electrical conductivity, pH of substrate solution, leaf number, plant diameter, leaf area, dry matter, content and accumulation of macronutrients and micronutrients, nitrate and potassium in the sap and the substrate solution and green intensity leaf, the ratio of leaf area... (Complete abstract click electronic access below)
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Controle biológico como componente do manejo integrado de doenças fúngicas em begônia

Fujinawa, Miriam Fumiko [UNESP] 16 April 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-04-16Bitstream added on 2014-06-13T19:23:49Z : No. of bitstreams: 1 000739516.pdf: 1650325 bytes, checksum: a1b57134d48fa771d7c3cfd4a0dce580 (MD5) / As espécies de Trichoderma spp. e Clonostachys rosea são bastante estudadas atualmente para o controle biológico de doenças de plantas. O objetivo deste trabalho foi avaliar o potencial dos antagonistas, Trichoderma asperellum (LQC96) e Clonostachys rosea (LQC62), no controle biológico das principais doenças fúngicas de begônia (mofo cinzento, mancha de Mirotécio e podridão do colo). A etiologia da podridão do colo em begônias foi estudada por meio das análises de suas características morfológicas e moleculares. Foram realizados ensaios in vitro a fim de verificar os mecanismos envolvidos no controle biológico dessas doenças, avaliados por meio da produção de compostos voláteis e compostos solúveis com ação inibitória aos patógenos, além da capacidade hiperparasítica dos antagonistas. A metodologia para avaliar os compostos voláteis consistiu em posicionar dois fundos de placas de Petri sobrepostas, contendo em uma delas cultura do antagonista e em outra, do patógeno. Para avaliar os compostos solúveis, foram utilizadas duas metodologias, o método em cultivo sobre o papel celofane para LQC96 e o método do filtrado da cultura líquida para LQC62. O hiperparasitismo foi avaliado por meio de culturas pareadas. Verificou-se a colonização e a supressão da esporulação em discos e em hastes de begônias. Após a análise do potencial in vitro, foram realizadas ensaios em casa de vegetação, a fim de verificar o controle dessas doenças em cultivo comercial de begônia. Nos ensaios in vitro, verificou-se que os antagonistas tiveram atividade antagônica contra esses patógenos, com a produção de compostos voláteis e solúveis, além de demonstrar a capacidade hiperparasítica de ambos antagonistas. Ambos agentes de controle biológico avaliados foram capazes de colonizar os discos e hastes de begônia e a aplicação preventiva na concentração de... / Currently the species of Trichoderma spp. and Clonostachys rosea are widely studied for biological control of plant diseases. The aim of this study was to evaluate the potential of these isolates these antagonists (T. asperellum LQC96 and C. rosea LQC62) in the biological control of major fungal diseases of begonia (gray mold, Myrothecium leaf spot and stem rot). The etiology of stem rot was studied using morphological and molecular analysis. In vitro assays were performed to verify the mechanisms involved in the biological control of these diseases, measured by the production of volatile and soluble compounds with an inhibitory effect on pathogens and the ability of antagonist hyperparasitism. The methodology for assessing the volatiles consisted of placing two Petri dishes superimposed on one culture containing the antagonist and another pathogen. To evaluate soluble compounds, two methods were used, the cultivation on cellophane for LQC96 and and the culture liquid filtrate method for LQC62. The hyperparasitism was assessed using paired cultures. There colonization and suppression of sporulation was evaluate on leaf disks and stem of begonias. After analysis of the potential in vitro assays, were performed in a greenhouse in order to verify the control of these diseases in commercial cultivation of begonia. In vitro assays was found that the antagonists were antagonistic activity against these pathogens, producing volatile and soluble compounds, and demonstrate the ability of hyperparasitism. Both biocontrol agents evaluated were able to colonize the leaf discs and stem of begonia and preventive application in concentration of 1x107 conidia mL-1 proved to be the most effective in suppressing pathogen sporulation on leaf discs and stem of begonia. The essay on commercial cultivation decreased the incidence of diseases with weekly application of antagonists. For control of gray mold and ...
39

Controle biológico como componente do manejo integrado de doenças fúngicas em begônia /

Fujinawa, Miriam Fumiko. January 2013 (has links)
Orientador: Antonio de Goes / Coorientador: Marcelo Augusto Boechat Morandi / Coorientador: Káthia Fernandes Lopes Pivetta / Banca: Rita de Cássia Panizzi / Banca: Edson Luiz Furtado / Banca: Adelmo Golynski / Banca: Helson Martins do Vale / Resumo: As espécies de Trichoderma spp. e Clonostachys rosea são bastante estudadas atualmente para o controle biológico de doenças de plantas. O objetivo deste trabalho foi avaliar o potencial dos antagonistas, Trichoderma asperellum (LQC96) e Clonostachys rosea (LQC62), no controle biológico das principais doenças fúngicas de begônia (mofo cinzento, mancha de Mirotécio e podridão do colo). A etiologia da podridão do colo em begônias foi estudada por meio das análises de suas características morfológicas e moleculares. Foram realizados ensaios in vitro a fim de verificar os mecanismos envolvidos no controle biológico dessas doenças, avaliados por meio da produção de compostos voláteis e compostos solúveis com ação inibitória aos patógenos, além da capacidade hiperparasítica dos antagonistas. A metodologia para avaliar os compostos voláteis consistiu em posicionar dois fundos de placas de Petri sobrepostas, contendo em uma delas cultura do antagonista e em outra, do patógeno. Para avaliar os compostos solúveis, foram utilizadas duas metodologias, o método em cultivo sobre o papel celofane para LQC96 e o método do filtrado da cultura líquida para LQC62. O hiperparasitismo foi avaliado por meio de culturas pareadas. Verificou-se a colonização e a supressão da esporulação em discos e em hastes de begônias. Após a análise do potencial in vitro, foram realizadas ensaios em casa de vegetação, a fim de verificar o controle dessas doenças em cultivo comercial de begônia. Nos ensaios in vitro, verificou-se que os antagonistas tiveram atividade antagônica contra esses patógenos, com a produção de compostos voláteis e solúveis, além de demonstrar a capacidade hiperparasítica de ambos antagonistas. Ambos agentes de controle biológico avaliados foram capazes de colonizar os discos e hastes de begônia e a aplicação preventiva na concentração de ... / Abstract: Currently the species of Trichoderma spp. and Clonostachys rosea are widely studied for biological control of plant diseases. The aim of this study was to evaluate the potential of these isolates these antagonists (T. asperellum LQC96 and C. rosea LQC62) in the biological control of major fungal diseases of begonia (gray mold, Myrothecium leaf spot and stem rot). The etiology of stem rot was studied using morphological and molecular analysis. In vitro assays were performed to verify the mechanisms involved in the biological control of these diseases, measured by the production of volatile and soluble compounds with an inhibitory effect on pathogens and the ability of antagonist hyperparasitism. The methodology for assessing the volatiles consisted of placing two Petri dishes superimposed on one culture containing the antagonist and another pathogen. To evaluate soluble compounds, two methods were used, the cultivation on cellophane for LQC96 and and the culture liquid filtrate method for LQC62. The hyperparasitism was assessed using paired cultures. There colonization and suppression of sporulation was evaluate on leaf disks and stem of begonias. After analysis of the potential in vitro assays, were performed in a greenhouse in order to verify the control of these diseases in commercial cultivation of begonia. In vitro assays was found that the antagonists were antagonistic activity against these pathogens, producing volatile and soluble compounds, and demonstrate the ability of hyperparasitism. Both biocontrol agents evaluated were able to colonize the leaf discs and stem of begonia and preventive application in concentration of 1x107 conidia mL-1 proved to be the most effective in suppressing pathogen sporulation on leaf discs and stem of begonia. The essay on commercial cultivation decreased the incidence of diseases with weekly application of antagonists. For control of gray mold and ... / Doutor
40

Desenvolvimento e acúmulo de nutrientes em duas espécies de orquídeas: Dendorobium nobile Lindl. e Miltonia flavescens Lindl. var. stellata Regel

Ichinose, Juliana Garcia dos Santos [UNESP] 20 November 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-11-20Bitstream added on 2014-06-13T20:18:17Z : No. of bitstreams: 1 ichinose_jgs_me_jabo.pdf: 457256 bytes, checksum: fb61f5d3094f0c5220d65828fb2e441d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Orquídeas estão entre as plantas mais distribuídas pelo mundo e mais cultivadas, sendo muito apreciadas por sua diversidade de cores e formas. Entretanto, estudos acerca de desenvolvimento e nutrição deste grupo de plantas são incipientes. Este trabalho teve como objetivo estudar o desenvolvimento e o acúmulo de nutrientes de 2 espécies de orquídeas cultivadas em condições de ambiente protegido, em vaso: i) Dendrobium nobile Lindl, ii) Miltonia flavescens Lindl. var. stellata Regel. As plantas foram adubadas semanalmente com 100 mL da solução nutritiva de Sarruge a 75% da concentração. Foi coletada mensalmente, durante 12 meses, de forma aleatória, 1 planta/repetição (totalizando 4). Estas foram avaliadas quanto ao número de folhas, área foliar, número, comprimento e diâmetro de pseudobulbos, número de brotos. Depois de lavadas e secas, determinaram-se a massa de matéria seca e os nutrientes nas diferentes partes. Até a fase do florescimento (240 DAPA), ambas as espécies já haviam acumulado mais de 50% do total de matéria seca verificado ao final das avaliações. A ordem de absorção e a quantidade de nutrientes absorvidos, ao final do ensaio foram: i) Dendrobium – macronutrientes, em mg planta-1, K (701,07) > N (339,44) > Ca (289,03) > Mg (135,44) > P (118,83) > S (23,56); micronutrientes, em Vg planta-1, Fe (14122,35) > Zn (5277,82) >Mn (3216,87) > B (1253,02) > Cu (271,25). ii) Miltonia – macronutrientes, em mg planta-1, K (316,93) > Ca (177,55) > N (143,48) > Mg (72,23) > P (66,65) > S (8,83); micronutrientes, em Vg planta-1, Fe (8939,8) > Zn (4938,1) > Mn (2571,7) > B (802,26) > Cu (208,96). / Orchids are among the plants more distributed throughout the world and more cultivated. They are very appreciated for their diversity of colors and forms. However, studies concerning the development and nutrition of this group of plants are incipient. This work had as objective to study the development and the accumulation of nutrients of 2 species of orchids, cultivated in conditions of greenhouse, in vase: i) Miltonia flavescens Lindl. var. stellata Regel; ii) Dendrobium nobile Lindl.. The plants were weekly fertilized with 100 mL of the nutritive solution of Sarruge at 75% of concentration. It was collected monthly, for 12 months, in a random way, 1 plant/repetition (totalizing 4). The number of leaves; the leaf area; number, length and diameter of pseudobulbs and the number of sprouts were evaluated. After washing and drying the plants, the mass of dry matter and the nutrients in the different parts were determined. Until the period of the flowering (240 DAPA), both species had already accumulated more than 50% of the total dry matter verified at the end of the evaluations. The absorption order and the amount of absorbed nutrients, at the end of the experiment were: i) Dendrobium – macronutrients, in mg plant-1 K (701.07)> N (339.44)> Ca (289.03)> Mg (135.44)> P (118.83)> S (23.56); micronutrients, Vg plant-1, Fe (14122.35)> Zn (5277.82)> Mn (3216.87)> B (1253.02)> Cu (271.25). ii) Miltonia – macronutrients, in mg plant-1, K (316.93)> Ca (177.55)> N (143.48)> Mg (72.23)> P (66.65)> S (8.83); micronutrients, Vg plant-1, Fe (8939.8)> Zn (4938.1)> Mn (2571.7)> B (802.26)> Cu (208.96).

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