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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Silvicultural Considerations for the Reintroduction of American Chestnut, <i>Castanea dentata</i>, to the Forests of the Eastern United States

Pinchot, Cornelia Cooper Wells 01 August 2011 (has links)
In anticipation of widespread planting of putatively blight-resistant hybrid chestnuts (Castanea spp.), it is critical to understand the silvics and competitive ability of the species. This dissertation examines preliminary growth and survival of several species and genetic crosses of chestnut grown as 1-0 high-quality nursery seedlings and planted in two study sites: Southeastern Kentucky (Daniel Boone National Forest; chapter 2), and Northeastern Connecticut (Yale-Myers Forest; chapter 4). The effects of three silvicultural treatments on the Daniel Boone National Forest (DBNF), and four silvicultural treatments on the Yale-Myers Forest (YM) were evaluated. Furthermore, the effect of initial seedling size on seedling performance was tested. In both studies, seedlings grew largest in height and root collar diameter in silvicultural treatments with the most available light. High mortality at the DBNF planting was caused by Phytophthora cinnamomi, ink disease, and high mortality at the YM planting was caused by repeated deer, Odocoileus virginianus, browsing and competition from hay-scented fern, Dennstaedtia punctilobula. Additionally, seedlings at the DBNF study were repeatedly defoliated by Craesus castaneae, chestnut sawfly, during the first growing season (chapter 3). Seedlings with larger root collar diameters at planting demonstrated greater survival and growth in the DBNF study while seedlings larger in height and RCD added less growth and were more likely to die in the YM study, likely due to the high deer population and dense understory competition. These results indicate that silvicultural treatments that create high-light environments are ideal for chestnut, however the species can establish successfully under a variety of light conditions, from low light [10% photosynthetically active radiation (PAR)] to high light (65% PAR). Ink disease will present a formidable obstacle to chestnut reintroduction efforts in the south, while northern efforts will be challenged by deer browsing due to overpopulated deer herds.
2

Seedling quality, plant growth and fruit yield and quality of tomato (Solanum lycopersicum L.) in response to Trichoderma harzianum and arbuscular mycorrhizal fungi

Nzanza, Bombiti 04 September 2012 (has links)
Existing evidence suggested that nursery inoculation with Trichoderma harzianum and arbuscular mycorrhizal fungi (AMF) could reduce deleterious effects of biotic and abiotic stresses and improve seedling quality, fruit yield and quality of tomato (Solanum lycopersicum L.). However, studies of their combined inoculation on seedling growth, fruit yield and quality of tomato plants are not well-documented. Experiments were carried out to investigate the combined effect of T. harzianum and AMF on tomato crop performance under various conditions. When combined with a T. harzianum and AMF mixture, seaweed extract from Ecklonia maxiama inhibited AMF root colonisation of tomato seedlings. Treating seedlings with a mixture of T. harzianum and AMF reduced the incidence of Verticillium wilt in tomato grown in a nethouse at early season, with negligible effect on fruit yield. Further investigations were initiated to find out whether T. harzianum and AMF were efficient when applied as a mixture or alone, at different inoculation times. Co-inoculation with T. harzianum and AMF (Glomus mosseae) improved seedling growth and development, except when both fungi were simultaneously applied two weeks after sowing. When the seedlings were allowed to grow up until full harvest in a greenhouse, both fungal inoculants increased total yield and marketable yield, but these increases were not significant. Furthermore, inoculation with AMF increased the percentage of extra-large fruit. Field experiments conducted under commercial tomato production confirmed greenhouse studies. Inoculation of tomato with T. harzianum and AMF, either alone or in combination increased early fruit yield (four first harvesting weeks). Throughout the studies, percentage AMF root colonisation in seedlings and plants remained low, despite nursery inoculation. Field experiments investigated the effects of AMF-inoculated transplants combined with biochar-amended soils on AMF root colonisation and their resultant effects on overall crop performance and microbial community structure. Biochar had no effect on AMF root colonisation, and also when combined with AMF, it had no influence on tomato productivity. Interestingly, biochar altered the fungal community while AMF might have influenced the bacterial community such as plant-growth promoting rhizobacteria, which are associated with improved plant growth, nutrient uptake and disease control in the rhizosphere. These benefits could contribute to improved yield and fruit quality. In conclusion, although the results were variable, there was a clear indication that T. harzianum and AMF can play an important role in tomato production. / Thesis (PhD)--University of Pretoria, 2012. / Plant Production and Soil Science / unrestricted
3

Assessment of a Seedling-Based Approach to Aspen Restoration in the Intermountain West

Howe, Alexander Addison 01 May 2018 (has links)
Quaking aspen (Populus tremuloides) is an important species ecologically and culturally in the western U.S., where it is one of the only broadleaf trees in the mostly conifer-dominated forests. Aspen management in the West has focused on regenerating existing stands vegetatively through root suckering, however this approach is restricted to locations where aspen currently exists and limits the genetic diversity of aspen populations. Planting nursery-grown aspen seedlings offers a potential method for overcoming these limitations, but it has received little attention in the U.S. Intermountain West (IW) to date. In order for this approach to be more broadly implemented, nursery protocols designed to grow high-quality aspen seedlings are needed, along with an understanding of what the major challenges to seedling establishment will be. With the assistance of my committee, my research tested a seedling-based approach to aspen restoration in an IW context in two phases. I first used nursery protocols developed for boreal aspen to grow seedlings collected from IW sources in order to assess whether modification of the protocols would be necessary. I then planted the seedlings I grew at three sites in southwestern Utah and monitored their growth and survival over two years. Results from the nursery phase suggest that protocols will need to be modified in order to produce a more consistent response from IW aspen seedlings. In the field, only 10% of the seedlings survived, though the majority of survival occurred in just two locations where soil moisture remained highest during the driest part of the early summer. These results provide useful information to direct future research and suggest that with a better understanding of appropriate site selection, seedling-based aspen restoration could still become a viable management tool in the IW.
4

Bioss?lido na restaura??o florestal: forma??o de mudas e aduba??o de plantio / Biosolid in forestry restoration: seedling production and planting fertilization

Lima Filho, Pedro 22 May 2015 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-01-06T12:56:39Z No. of bitstreams: 1 2015 - Pedro Lima Filho.pdf: 2041277 bytes, checksum: b01482f603e849269eed9abdd8b8432c (MD5) / Made available in DSpace on 2017-01-06T12:56:39Z (GMT). No. of bitstreams: 1 2015 - Pedro Lima Filho.pdf: 2041277 bytes, checksum: b01482f603e849269eed9abdd8b8432c (MD5) Previous issue date: 2015-05-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / One of the main problems found in forestry stands intended for restoration is seedling quality. The goal of this research was to evaluate different tube volumes in seedling production, utilizing biosolid as the substrate, within the following species; Ceiba speciosa, Pseudobombax grandiflorum, Dalbergia nigra and Lafoensia glyptocarpa,. The experiment consisted of the seedling production stage and a development evaluation stage in the field. The treatments utilized were 55, 110, 180 and 280 cm? tubes. The seedling production phase was done under entirely randomized design composed of four replications of the 12 seedlings. The field phase was also done under entirely randomized design due to the seedling formation period, which was in different periods for each species. The 280 cm? tube provided the best seedling quality, regardless of the species, when the biosolid was utilized as substrate. Despite this, for the species Pseudobombax grandiflorum, Dalbergia nigra and Lafoensia glyptocarpa, it is possible to utilize the 180 cm? tubet for seedling formation while maintaining similar quality / Um dos principais problemas encontrados na forma??o de povoamentos visando ? restaura??o florestal ? a qualidade das mudas. O objetivo deste trabalho foi avaliar diferentes volumes de tubetes para a produ??o de mudas de Ceiba speciosa, Pseudobombax grandiflorum, Dalbergia nigra e Lafoensia glyptocarpa, utilizando o bioss?lido como substrato. O experimento constou da fase de produ??o das mudas e da avalia??o do desempenho dessas no campo. Os tratamentos utilizados foram os tubetes de 55, 110, 180 e 280 cm?. A fase de produ??o das mudas foi instalada em delineamento inteiramente casulalizado composto por quatro repeti??es de 12 mudas. A fase de campo tamb?m foi instalada em delineamento inteiramente causualizado. Devido ao tempo de forma??o das mudas, em ?pocas diferentes para cada esp?cie. O tubete de 280 cm? foi o que proporcionou a melhor de qualidade de mudas, independente da esp?cie, quando se utilizou o bioss?lido como substrato. Todavia, para as esp?cies Pseudobombax grandiflorum, Dalbergia nigra e Lafoensia glyptocarpa pode-se utilizar o tubete de 180 cm? para a forma??o das mudas, mantendo qualidade similar
5

Produção de mudas de cafeeiros sob efeitos de lâminas de irrigação, hidrorretentor e recipientes

Azevedo, José Maria Gonçalves de 31 July 2012 (has links)
Made available in DSpace on 2016-12-23T14:37:31Z (GMT). No. of bitstreams: 1 Jose Maria Goncalves Azevedo.pdf: 1327445 bytes, checksum: 9cca5bff22a60f999a277f89c8163df6 (MD5) Previous issue date: 2012-07-31 / A qualidade da muda de café é de fundamental importância no sucesso de uma lavoura. Dessa forma, este trabalho teve por objetivo analisar a qualidade de mudas de Coffea canephora Pierre ex Froehner, variedade Robusta Tropical (EMCAPER 8151 Robusta Tropical) e Coffea arabica L., cultivar Catuaí Vermelho (IAC 81) produzidas sob diferentes lâminas de irrigação, com e sem hidrorretentor em sacolas e tubetes. Os experimentos foram conduzidos no viveiro do Instituto Federal de Educação, Ciência e Tecnologia do Estado do Espírito Santo, Campus de Alegre, e montados em esquema de parcelas subsubdivididas 4 x 2 x 2, sendo nas parcelas lâminas de irrigação em quatro níveis (25; 40; 55 e 70% da ET0), nas subparcelas recipientes em dois níveis (tubete e sacola) e nas subsubparcelas hidrorretentor, em dois níveis (com e sem hidrorretentor), num delineamento inteiramente casualizado, com quatro repetições. Aos 140 dias de idade, foram avaliados: altura da planta, diâmetro do caule, área foliar, massa da parte aérea e raiz seca, relação da altura/diâmetro do caule, relação da parte aérea/raiz e índice de qualidade de Dickson. As mudas de C. canephora e de C. arabica, produzidas em sacolas, apresentaram desenvolvimento superior às mudas produzidas em tubetes. A lâmina de 40% da ET0 é a indicada para as mudas de C. canephora e de C. arabica produzidas em sacolas e para as mudas produzidas em tubetes, a lâmina de 70% da ET0 foi a que proporcionou o melhor desenvolvimento das mudas. O hidrorretentor promoveu o melhor desenvolvimento das mudas de C. canephora produzidas em sacolas, ao contrário das mudas de C. canephora produzidas em tubetes, que se desenvolveram melhor sem hidrorretentor. O hidrorretentor não exerceu influência na qualidade mudas C. arabica / The coffee seedling quality is of fundamental importance in the success of a crop field. Therefore, the objective of this study was to analyze the quality of Coffea canephora Pierre ex Froehner seedling, variety Robusta Tropical (EMCAPER 8151 Robusta Tropical) and Coffea arabica L., cultivate Catuaí Vermelho (IAC 81) grown under different irrigation levels, with and without hydroretentive in bags and tubes. The experiments were conducted in the Federal Institute of Education, Science and Technology s nursery in the state of Espírito Santo, Alegre&#8223;s Campus in a split-plot design 4 x 2 x 2, plots of irrigation level of four depths (25; 40; 55 e 70% of ET0), in the subplots recipients in two levels (tube and bag) and in the split split plots in two levels (with and without hydroretentive), in a completely randomize design with four replications. At one hundred and forty days of age, was evaluated: plant height, stem diameter, leaf area, shoot and root dry matter, ratio of height/stem diameter, ratio of matter/root and the Dickson&#8223;s quality index. The C. canephora and C. arabica seedlings grown in bags showed higher development to the seedlings grown in tubes. For the C. canephora and C. arabica seedlings grown in bags in the depth 40% of ET0 is the best and the tubes grown in the depth 70% of ET0 was the one that provided the best development of the seedling. The hydroretentive promoted the best development of the C. canephora seedlings produce in bags, unlike the C. canephora seedlings produce in tubes, which grew better in the absence of the hydroretentive. The hydroretentive had no influence on the quality of C. arabica seedlings
6

Superação de dormência e produção de mudas de Anacauíta (Schinus molle L.) / Overcome dormancy and seedlings production of anacauita (Schinus molle L.)

Leal, Cintia Müller 07 December 2015 (has links)
Submitted by Maria Beatriz Vieira (mbeatriz.vieira@gmail.com) on 2017-04-04T13:22:16Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_cintia_muller_leal.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-04-07T18:52:23Z (GMT) No. of bitstreams: 2 dissertacao_cintia_muller_leal.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-04-07T18:59:09Z (GMT) No. of bitstreams: 2 dissertacao_cintia_muller_leal.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-04-07T18:59:23Z (GMT). No. of bitstreams: 2 dissertacao_cintia_muller_leal.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-12-07 / Sem bolsa / Anacauíta (Schinus molle L.) é uma espécie arbórea de ocorrência nativa no Rio Grande do Sul, pioneira de pequeno porte, com importância ecológica, bioquímica e farmacológica, contudo suas sementes apresentam dormência, fato que dificulta a produção de mudas em escala comercial. Este trabalho objetivou avaliar métodos de superação de dormência das sementes de S. molle de um lote com 15 meses de armazenamento em câmara fria seca e germinação inicial de 5% quando submetidas a tratamento para superação de dormência com ácido sulfúrico por 160 minutos, utilizando diferentes tempos de escarificação mecânica (150, 300, 450 e 600 segundos) em escarificador elétrico equipado com lixa grão 80. O tratamento de 150 segundos de escarificação mecânica proporcionou maior percentual de germinação (61%), menor número de sementes mortas e plântulas anormais, maior massa seca e comprimento de plântulas aos sete dias, maior embebição e maior índice de velocidade de emergência (2,28). Para a produção de mudas desta espécie foram testados dois volumes de tubetes (100 e 175 mL) e quatro níveis de adubação com fertilizante de liberação controlada (FLC) Osmocote Plus, em um experimento fatorial 2 x 4. Os níveis de adubação com FLC foram zero, quatro, oito e doze gramas por litro de substrato. Os resultados quanto aos parâmetros de crescimento e qualidade de mudas, onde foram avaliados altura, diâmetro do coleto, número de folhas, relação altura/diâmetro do coleto, massa seca da raiz, massa seca da parte aérea, massa seca total, relação massa seca da parte aérea e massa seca da raiz, volume de raiz, índice de qualidade de Dickson, índice de clorofila, teor de clorofila a, clorofila b e carotenoides ao longo de 120 dias após a emergência das plântulas, revelou que o tubete de 175 mL e a dosagem de oito gramas de FLC por litro de substrato foi superior aos demais tratamentos por produzir mudas de anacauíta de alta qualidade. / Anacauita (Schinus molle L.) is arborea, native species in a Rio Grande do Sul small pioneer with ecological, biochemical and pharmacological importance, but its seeds present dormancy , a fact that hinders the production of seedlings on a commercial scale. This study aimed at evaluating methods of overcoming seed dormancy of S. molle of a batch of 15 months of storage in dry cold chamber and 5% germination when undergoing treatment to overcome dormancy with sulfuric acid for 160 minutes, using different times mechanical scarification (150, 300, 450 and 600 seconds) in electric scarifier equipped with 80 grit sandpaper. Treatment of 150 seconds of mechanical scarification showed higher germination percentage (61%), fewer dead seeds and abnormal seedlings, imbibition largest and most emergency velocity index (2.28). For the production of seedlings of this species were tested two volumes of tubes (100 and 175 mL) and four levels of fertilizer controlled release fertilizer (CRF) Osmocote Plus in 2 x 4 factorial experiment. Nutrient levels were CRF zero, four, eight and twelve grams per liter of substrate. The results regarding the growth parameters and quality seedlings, which were assessed height, stem diameter, number of leaves, height / stem diameter, root dry mass, dry mass of shoots, total dry matter, dry weight ratio of shoot and root dry mass, root volume, Dickson quality index, chlorophyll index, chlorophyll content a, chlorophyll b and carotenoids over 120 days after seedling emergence, revealed that the plastic tube 175 ml and the dose of CRF eight grams per liter substrate was superior to the other treatments for producing seedlings of high quality anacauita.
7

Estímulo mecânico na morfometria em mudas de Enterolobium contortisiliquum (Vell.) Morong / Mechanical stimulus as indicator of quality seedlings Enterolobium contortisiliquum (Vell.) Morong

Volkweis, Cátia Raquel 14 September 2012 (has links)
Made available in DSpace on 2017-07-10T17:37:54Z (GMT). No. of bitstreams: 1 2012_Catia_Raquel_Volkweis.pdf: 1311113 bytes, checksum: 5546893dffae3b1e21194697573bd0ad (MD5) Previous issue date: 2012-09-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study aimed to quantify the effects induced by mechanical stimuli on the quality of seedlings Enterolobium contortisiliquum (Vell.) Morong. Treatments include five intensities of mechanical stimulation (0, 5, 10, 20 and 40 pushups) made daily for thirty days. The mechanical stimuli were initiated on December 20, 2011. Made by one-way passage of a structure composed by a bar PVC pipe arranged horizontally and secured on a metal frame with bearings. At the end of the imposition of the treatments evaluated the quality of the changes through increases in shoot height (H) and stem diameter (C) and quantified to root dry mass (RDM) , leaf (MSF) and (MSPA), and calculated the absolute growth rate (AGR), leaf area (LA), specific leaf area (SLA), leaf area ratio (LAR), weight of sheet (RPF) and proceeded to determine the loss of electrolytes from roots (PER). All measurements were performed in four replicates of five seedlings per treatment. At this stage, the test was conducted according to a completely randomized design with four replications. On January 20, 2012, after the end of treatments, some of the seedlings of treatment and control of seedlings to 20 pushups daily were transplanted to pots with a capacity of 5 liters filled with sand grain size of 2 mm and kept in en- vegetation for 39 days under water restriction. At this stage, we adopted the design of randomized blocks in a factorial arrangement (2 x 14) composed of two intensities of mechanical stimuli and thirteen evaluations on time with four replicates of five seedlings. Data were subjected to analysis of variance with the help SISVAR 5.0 statistical software (FERREIRA, 2007) and subsequently analyzed by linear regression at 5% probability. Seedlings monkfish-the-woods submitted to mechanical stimuli for 30 days during hardening subjected to 20 mechanical stimuli voiced daily values of morphometric variables and test the loss of electrolytes indicative of a higher quality changes over seedlings not mechanically stressed But without greater resistance to drought after planting / O presente trabalho objetivou quantificar os efeitos induzidos por estímulos mecânicos sobre a qualidade de mudas de Enterolobium contortisiliquum (Vell.) Morong. Os tratamentos compreenderam cinco intensidades de estímulo mecânico (0, 5, 10, 20 e 40 flexões) efetuados diariamente durante trinta dias. Os estímulos mecânicos foram iniciados em 20 de dezembro de 2011. Efetuados por meio da passagem em sentido único de uma estrutura composta por uma barra de cano de PVC, disposta horizontalmente e fixada em uma estrutura metálica com rolamentos. Ao final do período de imposição dos tratamentos avaliou-se a qualidade da muda por meio dos incrementos na altura da parte aérea (H) e no do diâmetro do coleto (C), assim como quantificou-se a massa seca da raiz (MSR), da folha (MSF) e da parte aérea (MSPA), e calculou-se a taxa de crescimento absoluto (TCA), área foliar (AF), área foliar específica (AFE), razão área foliar (RAF), razão peso de folha (RPF) e procedeu-se a determinação da perda de eletrólitos de raízes (PER). Todas as quantificações foram executadas de quatro repetições de 5 mudas por tratamento. Nesta fase, o ensaio foi conduzido de acordo com um delineamento inteiramente ao acaso, com quatro repetições. Em 20 de janeiro de 2012, após o término dos tratamentos, parte das mudas do tratamento controle e das mudas submetidas a 20 flexões diárias foram transplantadas para vasos com capacidade de 5 litros preenchidos com areia de granulometria 2 mm e mantidos em casa-de-vegetação por 39 dias sob restrição hídrica. Nesta fase, adotou-se o delineamento em blocos ao acaso em arranjo fatorial (2 x 14) composto por duas intensidades de estímulos mecânicos e treze avaliações no tempo com quatro repetições de cinco mudas. Os dados foram submetidos à análise de variância com o auxilio software estatístico SISVAR 5.0 (FERREIRA, 2007) e posteriormente, submetidos à análise de regressão linear a 5% de probabilidade. Mudas de tamboril-da-mata submetidas à estímulos mecânicos por 30 dias na fase de rustificação submetidas a 20 estímulos mecânicos diários externaram valores das variáveis morfométricas e do teste da perda de eletrólitos indicativos de uma maior qualidade da muda em relação a mudas não estressadas mecanicamente, porém, sem maior resistência ao déficit hídrico pós plantio
8

Superação de dormência e produção de mudas de Anacauíta Schinus molle L. / Overcome dormancy and seedlings production of anacauita Schinus molle L.

Leal, Cintia Müller 07 December 2015 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2018-07-10T17:45:09Z No. of bitstreams: 1 Dissertação Versão Final.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-16T17:00:11Z (GMT) No. of bitstreams: 1 Dissertação Versão Final.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-16T17:36:03Z (GMT) No. of bitstreams: 1 Dissertação Versão Final.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) / Made available in DSpace on 2018-07-16T17:36:13Z (GMT). No. of bitstreams: 1 Dissertação Versão Final.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) Previous issue date: 2015-12-07 / Anacauíta (Schinus molle L.) é uma espécie arbórea de ocorrência nativa no Rio Grande do Sul, pioneira de pequeno porte, com importância ecológica, bioquímica e farmacológica, contudo suas sementes apresentam dormência, fato que dificulta a produção de mudas em escala comercial. Este trabalho objetivou avaliar métodos de superação de dormência das sementes de S. molle de um lote com 15 meses de armazenamento em câmara fria seca e germinação inicial de 5% quando submetidas a tratamento para superação de dormência com ácido sulfúrico por 160 minutos, utilizando diferentes tempos de escarificação mecânica (150, 300, 450 e 600 segundos) em escarificador elétrico equipado com lixa grão 80. O tratamento de 150 segundos de escarificação mecânica proporcionou maior percentual de germinação (61%), menor número de sementes mortas e plântulas anormais, maior massa seca e comprimento de plântulas aos sete dias, maior embebição e maior índice de velocidade de emergência (2,28). Para a produção de mudas desta espécie foram testados dois volumes de tubetes (100 e 175 mL) e quatro níveis de adubação com fertilizante de liberação controlada (FLC) Osmocote Plus, em um experimento fatorial 2 x 4. Os níveis de adubação com FLC foram zero, quatro, oito e doze gramas por litro de substrato. Os resultados quanto aos parâmetros de crescimento e qualidade de mudas, onde foram avaliados altura, diâmetro do coleto, número de folhas, relação altura/diâmetro do coleto, massa seca da raiz, massa seca da parte aérea, massa seca total, relação massa seca da parte aérea e massa seca da raiz, volume de raiz, índice de qualidade de Dickson, índice de clorofila, teor de clorofila a, clorofila b e carotenoides ao longo de 120 dias após a emergência das plântulas, revelou que o tubete de 175 mL e a dosagem de oito gramas de FLC por litro de substrato foi superior aos demais tratamentos por produzir mudas de anacauíta de alta qualidade. / Anacauita (Schinus molle L.) is arborea, native species in a Rio Grande do Sul small pioneer with ecological, biochemical and pharmacological importance, but its seeds present dormancy , a fact that hinders the production of seedlings on a commercial scale. This study aimed at evaluating methods of overcoming seed dormancy of S. molle of a batch of 15 months of storage in dry cold chamber and 5% germination when undergoing treatment to overcome dormancy with sulfuric acid for 160 minutes, using different times mechanical scarification (150, 300, 450 and 600 seconds) in electric scarifier equipped with 80 grit sandpaper. Treatment of 150 seconds of mechanical scarification showed higher germination percentage (61%), fewer dead seeds and abnormal seedlings, imbibition largest and most emergency velocity index (2.28). For the production of seedlings of this species were tested two volumes of tubes (100 and 175 mL) and four levels of fertilizer controlled release fertilizer (CRF) Osmocote Plus in 2 x 4 factorial experiment. Nutrient levels were CRF zero, four, eight and twelve grams per liter of substrate. The results regarding the growth parameters and quality seedlings, which were assessed height, stem diameter, number of leaves, height / stem diameter, root dry mass, dry mass of shoots, total dry matter, dry weight ratio of shoot and root dry mass, root volume, Dickson quality index, chlorophyll index, chlorophyll content a, chlorophyll b and carotenoids over 120 days after seedling emergence, revealed that the plastic tube 175 ml and the dose of CRF eight grams per liter substrate was superior to the other treatments for producing seedlings of high quality anacauita.
9

HIDROGEL COMO CONDICIONADOR DE SUBSTRATO PARA PRODUÇÃO DE MUDAS DE Eucalyptus dunnii Maiden / HIDRORETENTOR POLYMER IN SEEDLING PRODUCTION IN Eucalyptus dunnii MAIDEN

Navroski, Marcio Carlos 30 August 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The use of polymers hidroretentores mixed to the substrate, has the function of water retention and release in a gradual way to the plant, and may increase the efficiency of irrigation, reducing the consumption of water and fertilizers. The objective of this research was to evaluate the feasibility of using the hydrogel substrate added to the sowing of seedlings, verifying the chemical and physical properties on the substrate and the reflection on the growth of seedlings. The work was divided into six chapters, in Chapter I tested different dosages of polymer substrates and vegetable. The chemical and physical analysis of substrates and growth of seedlings demonstrate the improvement of the properties of the substrates, especially those related to water retention, and reflection on the growth of seedlings in the nursery. The use of 4 g L-1 of the hydrogel showed overall the best seedling development. In Chapter II we evaluated the relationship of the hydrogel with doses of controlled-release fertilizer. The use of the hydrogel showed improved physical and chemical characteristics of substrates, especially attributes involving storage and delivery of water to plant. The use of polymer hidroretentor in seedlings of Eucalyptus dunnii can reduce the use of fertilizer in 25 - 50% on average, with no loss in quality seedlings. The Chapter III was on the evaluation of the strengths-based polymer polyacrylamide seedling growth and the characteristics of the substrate, in addition to nutritional analysis after cultivation of seedlings in the nursery. The dosage around 4.5 g L-1 brings the best answer regarding morphological. The use of doses below 3 g L-1 or above 4.5 g L-1 could negatively influence the majority of the observed features. All the nutrients had a higher nutritional content in shoots in the presence of the hydrogel, as compared to micronutrients, there was a decrease in the content of all elements with increasing polymer dosage. Check the effect of the hydrogel in different irrigation was the goal in Chapter IV. In the absence of the hydrogel, the further development of seedlings was obtained with irrigation between 16 to 20 mm day -1. In the presence of 3 g L-1 hydrogel further development of seedlings was obtained with the irrigation of 12 mm day -1. In Chapter V we tested the effect of hydrogel in planting seedlings in pots, relating to irrigation frequencies. The polymer hidroretentor possible delay of all symptoms of water deficit assessed with higher influence when irrigation is performed less frequently. The economic evaluation of the costs with the use of hydrogel was discussed in Chapter VI. The use of lower doses, together with savings from the reduction of fertilization and especially with the water, the use of the hydrogel may represent reduction of production costs. In general, the results obtained with regard to the use of polymers hidroretentor confirm the information which hydrogel addition of the substrate optimizes the availability of water by accelerating the development of plants therefore better performance in absorbing water and nutrients. / A utilização de polímeros hidroretentores, misturados ao substrato, tem a função de retenção de água e a sua liberação de maneira gradativa para a planta, podendo aumentar a eficácia da irrigação, reduzindo o consumo de água e o uso de fertilizantes. O objetivo geral desta pesquisa foi avaliar a viabilidade do uso do hidrogel adicionado ao substrato na semeadura das mudas, verificando-se as propriedades químicas e físicas no substrato e o efeito no crescimento das mudas. O trabalho foi dividido em seis capítulos, no Cap. I foram testados diferentes substratos e dosagens do polímero vegetal. A análise química e física dos substratos e o crescimento das mudas demonstram a melhoria das propriedades dos substratos, principalmente as relacionadas à retenção de água, tendo reflexo no crescimento das mudas no viveiro. O uso de 4 g L-1 do hidrogel apresentou o melhor desenvolvimento das mudas de Eucalyptus dunnii. No Cap. II foi avaliada a relação do hidrogel com doses de adubação de liberação controlada. O uso do hidrogel apresentou melhoria das características químicas e físicas dos substratos, principalmente aos atributos que envolvem armazenamento e disponibilização de água à planta. O uso do polímero hidroretentor na produção de mudas de Eucalyptus dunnii pode reduzir o uso de adubação em 25 - 50%, em média, não havendo prejuízo na qualidade das mudas. O Cap. III foi relativo à avaliação das dosagens do polímero a base de poliacrilamida no crescimento das mudas e nas características do substrato, além da análise nutricional das mudas após o cultivo no viveiro. A dose em torno de 4,5 g L-1 ocasionou a melhor resposta quanto às características morfológicas. O uso de dosagens abaixo de 3 g L-1 ou acima de 4,5 g L-1 influenciaram negativamente na maioria das características observadas. Quanto ao teor nutricional houve maior concentração de macronutrientes na parte aérea na presença do hidrogel, já em relação aos micronutrientes, houve decréscimo no teor de todos os elementos com o aumento da dose do polímero. Verificar o efeito do hidrogel em diferentes lâminas de irrigação foi o objetivo no Cap. IV. Na ausência do hidrogel, o maior desenvolvimento das mudas foi obtido com as lâminas de irrigação entre 16 a 20 mm dia -1. Na presença de 3 g L-1 de hidrogel o maior desenvolvimento das mudas foi obtido com a irrigação de 12 mm dia -1. No Cap. V testou-se o efeito do hidrogel no plantio das mudas em vasos, relacionando com frequências de irrigação. O polímero hidroretentor possibilitou o retardamento de todos os sintomas de déficit hídrico avaliados apresentando maior influência quando a irrigação é efetuada em menor frequência. A avaliação econômica do uso do hidrogel foi abordado no Cap. VI. O uso de menores doses, aliado a economia obtida com a redução da adubação e principalmente com o consumo de água, o uso do hidrogel pode representar redução dos custos de produção. Em geral, os resultados obtidos com relação ao uso de polímeros hidrorretentores ratificam a informação que a adição de hidrogéis no substrato otimiza a disponibilidade de água, acelerando o desenvolvimento das plantas, em consequência de uma melhor performance na absorção de água e nutrientes.

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