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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

Crescimento de mudas frutíferas sob ação de microrganismos promotores de crescimento / Growth of fruit seedlings under the action of growth promoting microorganisms

Santos, Carlos Henrique Barbosa [UNESP] 05 September 2017 (has links)
Submitted by CARLOS HENRIQUE BARBOSA SANTOS null (carlosufrb@hotmail.com) on 2017-10-18T12:25:03Z No. of bitstreams: 1 Tese_Carlos_Henrique_Barbosa_Santos.pdf: 953644 bytes, checksum: 56603e75ff2fec6f11d766aa8ee7d73a (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-10-23T17:35:43Z (GMT) No. of bitstreams: 1 santos_chb_dr_jabo.pdf: 953644 bytes, checksum: 56603e75ff2fec6f11d766aa8ee7d73a (MD5) / Made available in DSpace on 2017-10-23T17:35:43Z (GMT). No. of bitstreams: 1 santos_chb_dr_jabo.pdf: 953644 bytes, checksum: 56603e75ff2fec6f11d766aa8ee7d73a (MD5) Previous issue date: 2017-09-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A utilização de microrganismos promotores do crescimento de plantas (MPCP) tem sido aceita como alternativa a redução do uso de adubos químicos. O objetivo deste trabalho foi avaliar dois métodos de encapsulamento de diferentes MPCP para verificar o estabelecimento destes microrganismos no solo e, consequentemente, o efeito do uso dos MPCP no crescimento de mudas de espécies frutíferas. O inóculo microbiano continha as seguintes espécies: Azospirillum brasilense, Burkolderia cepacia, Bacillus thuringienses, B. megaterium, B. cereus, B. subtilis, Tricoderma spp. e Isolado 411. As espécies frutíferas avaliadas foram: Myrciaria cauliflora (DC.) O. Berg (jabuticaba); Myrciaria glazioviana (Kiaersk.) G. Barros & Sobral (cabeludinha); Myrciaria dubia (Kunth) Mc Vaugh (camu-camu); Eugenia brasiliensis Lam. (grumixama); Diospyros kaki L. (caqui); Garcinia brasiliensis Mart. (bacupari); Annona muricata L. (graviola); Duguetia lanceolata A. St. – Hil. (pindaíba); Chrysophyllum cainito L. (caimito); Anacardium occidentale L. (caju); Eriobotrya japonica (Thunb.) Lindl. (nêspera) e Litchi chinensis Sonn. (lichia). O delineamento experimental foi inteiramente casualizado (DIC), em esquema fatorial 3 (controle, alginato de sódio e argila) x 2 (presença e ausência de inóculo microbiano) com cinco repetições (uma muda por repetição). As mudas foram mantidas em 50% de iluminação à temperatura média de 22,5°C, durante noventa dias, sendo avaliada a altura da planta, diâmetro do colo, massa seca da parte aérea e de raiz, atividade enzimática da desidrogenase, determinação do amônio e nitrato, fosfato solúvel em bicarbonato, carbono da biomassa microbiana e número total de bactérias. O diâmetro do caule para as mudas de M. dubia foi maior quando não se utilizou os MPCP, sejam eles encapsulados ou não. A presença de MPCP, independentemente do encapsulante utilizado, promoveu melhor desenvolvimento das mudas de caimito (altura, diâmetro do caule e massa seca de raiz) e de lichia (diâmetro do caule e massa seca da planta). Desta forma, os MPCP favorecem o crescimento das mudas destas espécies. A atividade microbiana no substrato não foi influenciada pela adição de microrganismos encapsulados. Os agentes encapsulantes argila e alginato de sódio, com ou sem inóculo microbiano, podem modificar a atividade enzimática da desidrogenase, o nitrogênio e o carbono da biomassa microbiana no solo, porém são dependentes da espécie frutífera cultivada. / The use of plant growth promoting microorganisms (PGPM) has been accepted as an alternative to reduce the use of chemical fertilizers. The objective of this study was to evaluate two methods of encapsulation of different PGPM to verify the establishment of these microorganisms in the soil and, consequently, the effect of PGPM on the growth of seedlings of fruit species. The microbial inoculums contained the species: Azospirillum brasilense, Burkolderia cepacia, Bacillus thuringienses, B. megaterium, B. cereus, B. subtilis, Tricoderma spp. and Isolado 411. The fruit species evaluated were: Myrciaria cauliflora (DC.) O. Berg; Myrciaria glazioviana (Kiaersk.) G. Barros & Sobral; Myrciaria dubia (Kunth) Mc Vaugh; Eugenia brasiliensis Lam.; Diospyros kaki L.; Garcinia brasiliensis Mart.; Annona muricata L.; Duguetia lanceolata A. St. – Hil.; Chrysophyllum cainito L.; Anacardium occidentale L.; Eriobotrya japonica (Thunb.) Lindl. and Litchi chinensis Sonn. The experimental design was a completely randomized, in a factorial arrangement 3 (control, sodium alginate and clay) x 2 (presence and absence of microbial inoculum) with five replicates (one seedling per replicate). Seedlings were maintained in 50% illumination at an average temperature of 22.5 °C for ninety days, and evaluated for plant height, diameter, root shoot and stem dry shoot, enzymatic activity of dehydrogenase, determination of ammonium and nitrate, bicarbonate soluble phosphate, carbon of the microbial biomass and total number of bacteria. The stem diameter of M. dubia seedlings was higher when PGPM was not used, either encapsulated or not. The presence of PGPM, regardless the encapsulant used, promoted a better development of C. cainito (height, stem diameter and root dry mass) and L. chinensis (stem diameter and plant dry mass) seedlings. In this way, the PGPM favor the growth of the seedlings of these species. Microbial activity in the substrate was not influenced by the addition of encapsulated microorganisms. The encapsulating agent clay and sodium alginate, with or without microbial inoculum, may modify the enzymatic activity of the dehydrogenase, the nitrogen and the carbon of the microbial biomass in the soil, but are dependent on the cultivated fruit species.
32

Diversidade e potencial de utilização de bactérias fixadoras de N2 em Brachiaria brizantha / Diversity and potential use of N2-fixing bacteria in Brachiaria

Dias, Márcio de Souza 06 March 2015 (has links)
Made available in DSpace on 2016-05-02T13:55:22Z (GMT). No. of bitstreams: 1 Marcio de Souza Dias Dissertacao.pdf: 1130526 bytes, checksum: 33886098250a3d16ad0626a969014e45 (MD5) Previous issue date: 2015-03-06 / Coordenacao de Aperfeicoamento de Pessoal de Nïvel Superior / The objective of this research was to analyze the diversity of nitrogen fixing bacteria associated and endophytic B. brizantha, study the potential the solubility of inorganic phosphates of iron and aluminum, produce acid-3-indole acetic (AIA) and to evaluate the effect of inoculation of these isolates in Brachiaria brizantha cv MG 05 Victoria. The bacteria were isolated from soil samples grown under Brachiaria and parts of plant tissue this grass, the dry and wet periods in the municipalities of Alfenas and Machado, southern Minas Gerais. Five semisolid culture media and semi-selective were used: FAM (Azospirillum amazonense), JMV (Burkholderia sp.), JNFb (Herbaspirillum spp.), LGI (A. amazonense) and NFb (Azospirillum spp.). The phosphate solubilization tests and AIA production were performed in vitro and were used as of 22 bacterial isolates selection criteria used in the inoculation of B. brizantha cv MG 5 Victoria, grown in pots containing 20 dm3 of soil. There were two cuts, in what form evaluated the following parameters: height (Al), width (LF) and leaf length (CF), number of tillers (NP), length (CR) and root dry mass (MSR) dry matter (DM), dry matter yield (PMS), neutral detergent fiber (NDF) and acid (ADF) and crude protein in dry matter (PBMS). A total of 332 isolates were obtained, most endophytic. The greatest number and diversity were from the city of Alfenas. During the rainy season was verified greater number and diversity of isolates in both municipalities, when compared to the dry season. Thirty-five isolates solubilized iron phosphate and 78 produced AIA, especially the isolated UNIFENAS 100-17, 21, 40 and 78, able to do both simultaneously. The inoculation of nitrogen fixing strains of endophytic origin and rhizospheric influenced the development of B. brizantha cv MG 5 victory, contributing to the production of MS, PMS and PBMS in the two cutting heights highlighting the UNIFENAS-100-16 isolated, 21, PBMS 78 whose content was more than 7%. / O objetivo desta pesquisa foi analisar a diversidade de bactérias diazotróficas associadas e endofíticas de Brachiaria brizantha, estudar o potencial destas em solubilizar fosfatos inorgânicos de ferro e alumínio, produzir ácido-3-indolacético (AIA) e avaliar o efeito da inoculação destes isolados em Brachiaria brizantha cv MG 05 Vitória. As bactérias foram isoladas de amostras de solos cultivados sob B. brizantha e partes de tecido vegetal desta gramínea, nos períodos seco e chuvoso, nos municípios de Alfenas e Machado, Sul de Minas Gerais. Foram utilizados cinco meios de cultura semissólidos e semisseletivos: FAM (Azospirillum amazonense), JMV (Burkholderia sp.), JNFb (Herbaspirillum spp.), LGI (A. amazonense) e NFb (Azospirillum spp.). Os testes de solubilização de fosfato e produção de AIA foram realizados in vitro e foram utilizados como critério de seleção dos 22 isolados bacterianos utilizados na inoculação de B. brizantha cv MG 5 Vitória, cultivada em vasos contendo 20 dm3 de solo. Foram realizados dois cortes, em que foram avaliados os seguintes parâmetros: altura (Al), largura (LF) e comprimento da folha (CF), número de perfilhos (NP), comprimento (CR) e massa seca da raiz (MSR), matéria seca (MS), produtividade de matéria seca (PMS), fibra em detergente neutro (FDN) e ácido (FDA) e a proteína bruta na matéria seca (PBMS). Foi obtido um total de 332 isolados, sendo a maioria endofíticos. O maior número e diversidade foram provenientes do município de Alfenas. No período chuvoso foi verificado maior número e diversidade de isolados em ambos os Municípios, quando comparado ao período da seca. Trinta e cinco isolados solubilizaram fosfato de ferro e 78 produziram AIA, destacando-se os isolados UNIFENAS 100-17, 21, 40 e 78, capazes de desempenhar ambas as funções simultaneamente. A inoculação de estirpes diazotróficas de origem endofíticas e rizosféricas influenciaram no desenvolvimento de B. brizantha cv MG 5 Vitória, contribuindo para a produção de MS, PMS e PBMS nas duas alturas de corte destacando-se os isolados UNIFENAS-100-16, 21, 78 cujo teor de PBMS foi superior a 7%.
33

Maize responsiveness to Azospirillum brasilense: insights into genetic control and genomic prediction / Responsividade do milho para Azospirillum brasilense: conhecimentos sobre controle genético e predição genômica

Vidotti, Miriam Suzane 25 January 2019 (has links)
The inoculation with Azospirillum brasilense is one of the main strategies to supplement the inorganic inputs of nitrogen (N) and to increase the root development in maize. However, the beneficial inoculation effects are not always reached, which, in part, is due to genotypic variation in the plant host, resulting in different degrees of outcome. In this context, we aimed to study the genetic control and genomic prediction of maize traits related to the responsiveness to A. brasilense inoculation. For this, 118 maize hybrids were conducted under N stress and N stress plus A. brasilense treatments in controlled conditions over 2016 and 2017 seasons. We evaluated root and shoot traits and performed diallel analyses, association mapping, and genomic prediction methods considering 59,215 Single-Nucleotide Polymorphism (SNP) markers. Our results revealed a quantitative inheritance of the partnership-related maize traits, with both additive and non-additive genetic effects involved in the genetic control. Furthermore, several candidate genes were identified for the maize-A. brasilense association, especially with heterozygous (dis)advantage effects. In general, the prediction accuracies were higher mostly for the inoculated treatment compared to the non-inoculated. Finally, our findings enable a deeper understanding towards the genetic basis of the maize responsiveness to A. brasilense and may support plant breeders to establish selection strategies aiming the development of superior genotypes for this association. / A inoculação com Azospirillum brasilense é uma das principais estratégias para suplementar os insumos inorgânicos de nitrogênio (N) e aumentar o desenvolvimento radicular do milho. No entanto, os efeitos benéficos da inoculação nem sempre são alcançados, o que, em parte, é devido à variação genotípica da planta hospedeira, que ocasiona diferentes graus de resultados. Neste contexto, nosso objetivo foi estudar o controle genético e a predição genômica de caracteres de milho relacionados à responsividade para a inoculação com A brasilense. Para isso, 118 híbridos de milho foram conduzidos sob estresse de N e estresse de N mais A brasilense em condições controladas nos anos de 2016 e 2017. Nós avaliamos características de raiz e parte aérea e realizamos análises dialélicas, mapeamento associativo e métodos de predição genômica considerando 59.215 marcadores Single-Nucleotide Polymorphism (SNP). Nossos resultados revelaram uma herança quantitativa das características do milho relacionadas à essa parceria, com efeitos genéticos aditivos e não-aditivos envolvidos no controle genético. Além disso, vários genes candidatos foram encontrados para a associação milho-A brasilense, especialmente com efeitos de (des)vantagens de heterozigotos. Em geral, as acurácias de predição foram mais maiores principalmente para o tratamento inoculado em comparação ao não inoculado. Finalmente, nossos resultados possibilitam uma compreensão mais aprofundada das bases genéticas da responsividade do milho à A. brasilense e podem auxiliar os melhoristas de plantas a estabelecerem estratégias de seleção visando o desenvolvimento de genótipos superiores para essa associação.
34

Avaliação de parâmetros do metabolismo de carbono e nitrogênio e de respostas ao estresse na associação de trigo com a bactéria Herbaspirillum seropedicae / Evaluation of carbon and nitrogen metabolism parameters and responses to stress in wheat association with bacteria Herbaspirillum seropedicae

Ortolan, Sarah Romani 28 July 2015 (has links)
Made available in DSpace on 2017-07-10T17:37:10Z (GMT). No. of bitstreams: 1 Sarah_Romano_Ortolan.pdf: 975526 bytes, checksum: d72ab61fc7bdc88b6ddbab0eb3a86e42 (MD5) Previous issue date: 2015-07-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Wheat is considered the main cereal diet of the world population, but in recent years has achieved some gain in productivity of this culture despite having increased the use of nitrogen fertilizer. The use of plant growth promoting bacteria such as Herbaspirillum seropedicae SmR1 among others has been studied to obtain development of plants with less use of nitrogen fertilizers. However there is little information relating the effects of this interaction in plant development and grain yield. Objective of this study was to evaluate the carbon and nitrogen metabolism by certain enzymes, metabolites and indices related to the response to infectious stress on the wheat cultivars CD 104 and CD 120 in association with Herbaspirillum seropedicae bacteria. Two experiments were conducted. The experimental design was completely randomized with four replications in a 4x2. The first factor relates to the conditions inoculation with bacteria and/or nitrogen source in coverage are: control without inoculation with bacteria or added nitrogen fertilizer (C); application of nitrogen fertilizer (50 kg.ha-1) 30 days after sowing (N); inoculation with 106 cells of the bacterium H. seropedicae/seed at planting (Hs) and inoculation with bacteria combined with the application of nitrogen fertilizer (Hs + N) and the second factor refers to the phenological stages (tillering and booting). The results indicated that inoculation with H. seropedicae in wheat seeds of cv.s CD 104 and CD 120 in the two growth stages answered in relation to the indices related to stress with the involvement of enzymes of carbon and nitrogen metabolism. However prominent effect was not noticed to promote plant growth of wheat in late development, nor a deleterious effect of the bacterium for inoculation cv. CD 104 under the experimental conditions. For cv. CD 120 the differential effects indicate lower levels of stress and some level of association to positive effect on productivity when combined inoculation of bacteria to nitrogen fertilization. It was concluded that as well as pathogenic and stressors, H. seropedicae able to beneficially associate with wheat also provides similar interference pattern of carbon and nitrogen metabolism and stress levels / O trigo é considerado o principal cereal da dieta da população mundial, entretanto nos últimos anos tem se obtido pouco ganho de produtividade desta cultura apesar de se ter aumentado o uso de fertilizante nitrogenado. O uso de bactérias promotoras do crescimento vegetal, como Herbaspirillum seropedicae SmR1 entre outras, tem sido estudado para se obter desenvolvimento de plantas com menor uso de fertilizantes nitrogenados. Entretanto existem poucas informações que relacionam os efeitos desta interação no desenvolvimento da planta e de produtividade de grãos. Objetivo deste trabalho foi avaliar o metabolismo de carbono e nitrogênio através de algumas enzimas, metabólitos e índices relacionados à resposta ao estresse infeccioso em trigo das cultivares CD 104 e CD 120 em associação com a bactéria Herbaspirillum seropedicae em dois estádios fenológicos. Foram realizados dois experimentos. O delineamento experimental utilizado foi o inteiramente ao acaso, com 4 repetições, em esquema fatorial 4x2. O primeiro fator refere-se às condições de inoculação com bactéria e/ou fertilização nitrogenada em cobertura, sendo: controle, sem inoculação com bactéria ou adição de fertilizante nitrogenado (C); aplicação de fertilizante nitrogenado (50 kg.ha-1) após 30 dias da semeadura (N); inoculação de 106 células da bactéria H. seropedicae/semente na semeadura (Hs) e inoculação com a bactéria combinada com a aplicação de fertilizante nitrogenado (Hs + N) e o segundo fator refere-se aos estádios fenológicos (perfilhamento e emborrachamento). Os resultados indicaram que a inoculação com H. seropedicae em sementes de trigo das cv.s CD 104 e CD 120 nos dois estádios fenológicos responderam em relação aos índices relacionados ao estresse com envolvimento das enzimas do metabolismo de carbono e nitrogênio. Entretanto não foi percebido efeito proeminente de promoção do crescimento vegetal no final do desenvolvimento do trigo, tampouco efeito deletério da inoculação de bactéria para a cv. CD 104, nas condições experimentais. Para a cv. CD 120 os efeitos diferenciais indicam menor nível de estresse e algum nível de associação para efeito positivo na produtividade quando combinada a inoculação da bactéria com a fertilização nitrogenada. Foi possível concluir que assim como para agentes patogênicos e estressantes, a H. seropedicae, capaz de associar beneficamente com trigo também apresenta padrão semelhante de interferência do metabolismo de carbono e nitrogênio e índices de estresse
35

Coberturas vegetais e modos de inoculação com Azospirillum brasilense em milho sobre três sistemas de preparo de solo /

Corsini, Daiene Camila Dias Chaves. January 2018 (has links)
Orientador: Orivaldo Arf / Resumo: Devido ao crescimento e a importância da utilização do milho segunda safra, pacotes tecnológicos que favoreçam o uso dessa nova época de cultivo para o milho são de extrema importância para a consolidação dessa safra. O manejo adequado do solo, a utilização de coberturas vegetais e considerando também os dados pouco consistentes na utilização da inoculação com bactérias promotoras de crescimento na cultura do milho, são práticas fundamentais para a busca de uma produção econômica e ambientalmente viável. Diante do exposto o objetivo desse trabalho foi o de avaliar o efeito das coberturas vegetais e dos modos de inoculação com Azospirillum brasilense nos diferentes sistemas de preparo do solo, no desenvolvimento e produtividade do milho segunda safra. O experimento foi desenvolvido nos anos agrícolas de 2013/14 e 2014/15 em área experimental da Fazenda de Ensino e Pesquisa pertencente à Faculdade de Engenharia de Ilha Solteira – UNESP, localizada no município de Selvíria – MS. O solo do local é do tipo LATOSSOLO VERMELHO-ESCURO Epi-eutrófico álico, textura argilosa, originalmente sob vegetação de cerrado. A precipitação média anual é de 1.313 mm e a temperatura média anual de 25°C. A área teve como cultura anterior a soja, e foi constituído por três subprojetos envolvendo coberturas vegetais (Crotalária spectabilis, Urochloa ruziziensis e C. spectabilis + U. ruziziensis), modos de inoculação com A. brasilense (testemunha - sem inoculação de A. brasilense, inoculação de A. bras... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Due to the growth and importance of the use of second crop maize, technological packages that enhance the use of this new maize season are extremely important for this crop consolidation. Adequate soil management, cover crops and also the inconsistent data on the use of inoculation with growth promoting bacteria in maize, are fundamental practices for the search for an economically and environmentally viable production. This study animed to evaluate the effect of plant cover and inoculation methods with Azospirillum brasilense on different soil preparation systems, on the development and productivity of second crop maize. The experiment was developed in the agricultural years of 2013/14 and 2014/15 in an experimental area of the Education and Research Farm belonging to the Faculty of Engineering of Ilha Solteira - UNESP, located in the municipality of Selvíria -MS. The soil of the site is of the type RED-DARK LATOSOL Epi-eutrophic alic, clayey texture, originally under cerrado vegetation. The average precipitation cancels out is 1313 mm and the average annual temperature is 25 ° C. The area was previously cultivated with soybean, and was constituted by three subprojects involving plant cover crops (Crotalaria spectabilis, Urochloa ruziziensis and C. spectabilis + U. ruziziensis), inoculation methods with A. brasilense (control - without inoculation of A. brasilense , inoculation of A. brasilense on maize seeds, inoculation of A. brasilense on maize seed and foliar - V4 stage ... (Complete abstract click electronic access below) / Doutor
36

Coberturas vegetais e modos de inoculação com Azospirillum brasilense em milho sobre três sistemas de preparo de solo / Cover crops and inoculation modes with Azospirillum brasilense in maize in three soil management systems

Corsini, Daiene Camila Dias Chaves 02 July 2018 (has links)
Submitted by Daiene Camila Dias Chaves Corsini (daieneagro@gmail.com) on 2018-11-09T18:57:12Z No. of bitstreams: 1 corsini_dcdc_dr_ilha.pdf: 3271631 bytes, checksum: 03bc61ace606b7d3a40171e912132c80 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-11-09T19:15:19Z (GMT) No. of bitstreams: 1 corsini_dcdc_dr_ilha.pdf: 3271631 bytes, checksum: 03bc61ace606b7d3a40171e912132c80 (MD5) / Made available in DSpace on 2018-11-09T19:15:19Z (GMT). No. of bitstreams: 1 corsini_dcdc_dr_ilha.pdf: 3271631 bytes, checksum: 03bc61ace606b7d3a40171e912132c80 (MD5) Previous issue date: 2018-07-02 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Devido ao crescimento e a importância da utilização do milho segunda safra, pacotes tecnológicos que favoreçam o uso dessa nova época de cultivo para o milho são de extrema importância para a consolidação dessa safra. O manejo adequado do solo, a utilização de coberturas vegetais e considerando também os dados pouco consistentes na utilização da inoculação com bactérias promotoras de crescimento na cultura do milho, são práticas fundamentais para a busca de uma produção econômica e ambientalmente viável. Diante do exposto o objetivo desse trabalho foi o de avaliar o efeito das coberturas vegetais e dos modos de inoculação com Azospirillum brasilense nos diferentes sistemas de preparo do solo, no desenvolvimento e produtividade do milho segunda safra. O experimento foi desenvolvido nos anos agrícolas de 2013/14 e 2014/15 em área experimental da Fazenda de Ensino e Pesquisa pertencente à Faculdade de Engenharia de Ilha Solteira – UNESP, localizada no município de Selvíria – MS. O solo do local é do tipo LATOSSOLO VERMELHO-ESCURO Epi-eutrófico álico, textura argilosa, originalmente sob vegetação de cerrado. A precipitação média anual é de 1.313 mm e a temperatura média anual de 25°C. A área teve como cultura anterior a soja, e foi constituído por três subprojetos envolvendo coberturas vegetais (Crotalária spectabilis, Urochloa ruziziensis e C. spectabilis + U. ruziziensis), modos de inoculação com A. brasilense (testemunha - sem inoculação de A. brasilense, inoculação de A. brasilense nas sementes do milho, inoculação de A. brasilense na semente do milho e via foliar - estádio V4 e inoculação de A. brasilense via foliar - estádio V4) em três sistemas de preparo de solo (plantio direto, cultivo mínimo e cultivo convencional). Os delineamentos experimentais foram de blocos casualizados em esquema de parcelas subdivididas em cada tipo de preparo do solo (subprojetos), sendo constituídos por três coberturas vegetais e quatro modos de inoculação com quatro repetições. Observou-se que no subprojeto com coberturas vegetais e modos de inoculação em sistema plantio direto, as coberturas vegetais obtiveram biomassa adequada para a manutenção de palha nesse sistema; a C. spectabilis obteve os maiores teores de nitrogênio (N) nas plantas e N acumulado, proporcionando as plantas de milho cultivadas após essa cobertura, maior altura de inserção de espigas; as plantas de milho cultivadas após a U. ruziziensis apresentou um maior população de Azospirillum por grama de solo. No cultivo mínimo, as coberturas vegetais obtiveram biomassa adequada para a manutenção de palha; para o teor de N, a espécie C. spectabilis apresentou maiores médias proporcionando as plantas de milho maior a altura de inserção de espiga, maior massa de plantas e maior população Azospirillum por grama de solo; a inoculação com A. brasilense via foliar proporcionou as plantas de milho maior massa seca de parte aérea; o modo de inoculação com A. brasilense proporcionou aumento da produtividade de grãos de milho quando essa foi feita nas sementes e via foliar. No sistema de preparo de solo convencional, as coberturas vegetais obtiveram biomassa adequada para a manutenção de palha, a massa seca de plantas de U. ruziziensis teve o maior valor médio e o maior acúmulo de N; a altura de plantas e altura de inserção de espigas foi maior quando houve a inoculação nas sementes de milho e via foliar com A. brasilense. / Due to the growth and importance of the use of second crop maize, technological packages that enhance the use of this new maize season are extremely important for this crop consolidation. Adequate soil management, cover crops and also the inconsistent data on the use of inoculation with growth promoting bacteria in maize, are fundamental practices for the search for an economically and environmentally viable production. This study animed to evaluate the effect of plant cover and inoculation methods with Azospirillum brasilense on different soil preparation systems, on the development and productivity of second crop maize. The experiment was developed in the agricultural years of 2013/14 and 2014/15 in an experimental area of the Education and Research Farm belonging to the Faculty of Engineering of Ilha Solteira - UNESP, located in the municipality of Selvíria -MS. The soil of the site is of the type RED-DARK LATOSOL Epi-eutrophic alic, clayey texture, originally under cerrado vegetation. The average precipitation cancels out is 1313 mm and the average annual temperature is 25 ° C. The area was previously cultivated with soybean, and was constituted by three subprojects involving plant cover crops (Crotalaria spectabilis, Urochloa ruziziensis and C. spectabilis + U. ruziziensis), inoculation methods with A. brasilense (control - without inoculation of A. brasilense , inoculation of A. brasilense on maize seeds, inoculation of A. brasilense on maize seed and foliar - V4 stage and inoculation of A. brasilense via foliar - V4 stage) in three soil tillage systems (no - tillage, no - tillage minimum and conventional cultivation). The experimental design was a randomized block design subdivided in each type of soil preparation (subprojects), consisting of three vegetation cover and four modes of inoculation with four replications. It was observed that in the subproject with vegetation cover and inoculation methods in no-tillage system, the vegetal cover obtained adequate biomass for the maintenance of straw in this system; C. spectabilis obtained the highest levels of nitrogen in the plants and N accumulated, providing the maize plants cultivated after this cover, greater height of spike insertion; maize plants grown after U. ruziziensis showed a larger population of Azospirillum per gram of soil. In the minimum cultivation, the vegetal coverings obtained adequate biomass for the maintenance of straw; for the N content, the species C. spectabilis showed higher mean values, giving the maize plants greater spike insertion height, larger plant mass and higher Azospirillum population per soil gram; the inoculation with A. brasilense via foliar provided the maize plants with the highest aerial part dry mass; the form of inoculation with A. brasilense provided an increase in the yield of maize grains when it was made in the seeds and foliar route. In the conventional tillage system, the plant cover obtained adequate biomass for the maintenance of straw, the dry mass of U. ruziziensis plants had the highest average value and the highest accumulation of N; plant height and spike insertion height were higher when inoculation was carried out on maize seeds and foliar route with A. brasilense. / FAPESP: 2013/26489-6
37

Modulation of growth and gene transcription of metabolic routes for nitrogen and phytohormones in Polypogon australis plants, mediated by the supernatant of a cyanobacterial culture

Pontigo Gallardo, Darlyng Rossio 05 July 2024 (has links)
Überstände von Cyanobakterien sind ein vielversprechendes Produkt zur Förderung des Pflanzenwachstums, da sie alle Vorteile der freigesetzten bioaktiven Verbindungen, wie z. B. Phytohormone, enthalten, ohne die Zwänge der mikrobiellen Inokulationen. Es ist jedoch nur wenig darüber bekannt, wie Cyanobakterien die Reaktion der Pflanzen auf molekularer Ebene modulieren könnten. In dieser Studie wurde das in Chile heimische Gras Polypogon australis als Modell verwendet, um die Wirkung von Überständen aus Kulturen von sieben autochthonen Bodencyanobakterien zu untersuchen. Von diesen zeigten die Überstände der Kulturen von Trichormus sp. die beste wachstumsfördernde Wirkung auf P. australis. Die ICP-MS-Analyse ergab, dass die Überstände von Trichormus sp. eine ähnliche Nährstoffzusammensetzung aufwiesen wie das für das Wachstum der Cyanobakterien verwendete Medium BG-11, mit Ausnahme der Elemente P und Mn, die in der späten exponentiellen Phase der Kulturen verarmt waren. Dann wurden Überstände von Trichormus sp.-Kulturen, die in der späten exponentiellen Phase gesammelt wurden und die eine Menge von 32,7 pmol trans-Zeatin pro mg Chl-a enthielten, zur Bewertung der Reaktion von P. australis auf transkriptioneller Ebene verwendet. Ein BG-11-Medium, das frei von P und Mn war, wurde als Kontrolle verwendet. Ganzes Pflanzengewebe wurde 3 Stunden nach der Behandlung entnommen und für eine RNA-seq-Analyse verwendet. Die Ergebnisse zeigten, dass die Überstände von Trichormus sp. die Pflanzenreaktion hauptsächlich über die N- und Phytohormonwege modulierten, die in engem Zusammenhang mit dem C- und Lipidstoffwechsel stehen. Die behandelten Pflanzen wiesen 4 und 8 Tage nach der Anwendung größere Triebe auf als die Kontrollpflanzen, aber es wurden keine Unterschiede bei der Wurzellänge festgestellt. Dieser Phänotyp lässt sich durch die Induktion von Genen für die Gibberellin-Biosynthese in P. australis erklären, die durch andere Hormone wie Auxine, Brassinosteroide und Ethylen unterstützt wird. Andererseits wurde in mit P. australis behandelten Pflanzen eine induzierte systemische Resistenzreaktion beobachtet, die hauptsächlich durch einen Ethylen-Jasmonat-Crosstalk vermittelt wurde. Diese Arbeit unterstützt die Verwendung von Überständen als eine gute Option zur Förderung des Pflanzenwachstums.:Table of content Preliminary Page Resumen i Abstract ii Übersetzung iii DECLARATION ix 1. Introduction 1 1.1. Plant-growth promoting microorganisms 1 1.2. Soil cyanobacteria 2 1.3. Physiology of soil cyanobacteria 2 1.4. Cyanobacterial plant growth-promoting molecules 4 1.5. Plant response to bioactive compounds 6 1.6. Cyanobacterial supernatants 9 1.7. Polypogon australis as a plant study model 11 2. Methodology 13 2.1. Obtention of the cyanobacterial cultures 13 2.2. Supernatant collection from the cyanobacterial cultures 14 2.3. Cyanobacterial biomass quantification 15 2.3.1. Chlorophyll-a content 15 2.3.2. Biomass dry weight 15 2.3.3. Determination of the growth phases 15 2.4. Chemical characterization of the supernatants 16 2.4.1. Nitrate content 16 2.4.2. Total element content 16 2.4.3. Zeatin content 16 2.5. Preparation of the modified BG-11 medium (BG-11M medium) 17 2.6. Bioassays with cyanobacterial supernatants 18 2.6.1. Effect of supernatants of the 25 mL cultures on P. australis germination 18 2.6.2. Effect of supernatants of the 25 mL cultures on P. australis plants 18 2.6.3. Effect of supernatants of the 2,400 mL cultures on P. australis plants 19 2.7. Statistical analysis 19 2.8. Determination of transcriptional changes in P. australis. 20 2.8.1. Plant treatments and tissue collection 20 2.8.2. Total RNA extraction from plant tissue 20 2.8.3. DNA removal 20 2.8.4. mRNA sequencing, de novo assembly, and differential expression analysis 21 2.8.5. Contig annotation and functional classification 22 3. Results 24 3.1. Trichormus sp. cultures produce the highest biomass content 24 3.2. Trichormus sp. cultures have a low P content 25 3.3. Trichormus sp. supernatants have the best growth-promoting effect on the growth of P. australis 25 3.4. Supernatant nutrient content of Trichormus sp. cultures change through the growth phases 27 3.5. Supernatants used in the transcriptomic assay and BG-11M medium have a lower nutrient content than BG-11 medium 30 3.6. Trichormus sp. supernatants promote the growth of P. australis to a greater extent than the BG-11M medium 32 3.7. Trichormus sp. supernatants contain zeatin 33 3.8. Trichormus sp. supernatants modulated more P. australis genes than the BG-11M medium 34 3.9. Trichormus sp. supernatants regulate the gene expression of growth and defense responses in P. australis 37 4. Discussion 57 4.1. The plant-growth promoting effect of Thrichormus sp. supernatants 57 4.2. The role of P and Mn in the growth-promoting effect of Trichormus sp. supernatants 58 4.3. Modulation of P. australis N-metabolism by Trichormus sp. supernatants 59 4.4. P. australis nitrogen and carbon metabolism in response to Trichormus supernatants 63 4.5. P. australis phytohormone-metabolism modulated by Trichormus supernatants 64 4.6. The role of lipid metabolism in the response to Trichormus supernatants 67 4.7. P. australis defense response triggered by Trichormus supernatants 68 4.8. Phytohormone crosstalk and defense response in P. australis treated with Trichormus sp. supernatants 71 4.9. Perspectives and challenges for the biotechnological use of Trichormus sp. supernatants 73 5. Conclusion 76 Bibliographic references 77 Annexes 116 / Cyanobacterial supernatants are a promising plant growth-promoting product since they contain all the advantages of the released bioactive compounds, such as phytohormones, without the constraints of microbial inoculations. However, little is known about how cyanobacteria could modulate the plant response at a molecular level. In this research, the Chilean native grass, Polypogon australis, was used as a model for assaying the effect of supernatants obtained from cultures of seven autochthonous soil cyanobacteria. Of them, supernatants of Trichormus sp. cultures showed the best growth-promoting effects on P. australis. Analysis by ICP-MS showed that Trichormus sp. supernatants had a similar nutrient composition to the medium used for the cyanobacteria growth, BG-11, except for the elements P and Mn, which were depleted when the late exponential phase of the cultures was reached. Then, supernatants of Trichormus sp. cultures collected in the late exponential phase, which contained an amount of 32.7 pmol of trans-zeatin per mg of Chl-a, were employed for evaluating the P. australis response at a transcriptional level. A BG-11 medium free of P and Mn was utilized as a control. Whole plant tissue was collected 3 h-post treatment and used for an RNA-seq analysis. Results showed that Trichormus sp. supernatants modulated the plant response mainly by the N and phytohormones pathways, in close relation with C and lipid metabolism. Treated plants showed larger shoots than control plants 4 and 8 days after application, but no differences were observed in root length. This phenotype can be explained by the induction in P. australis of gibberellin biosynthesis genes, supported by other hormones such as auxins, brassinosteroids, and ethylene. On the other hand, an induced systemic resistance response was observed in P. australis-treated plants, mostly mediated by an ethylene-jasmonate crosstalk. This work supports the use of supernatants as a good plant growth-promoting option.:Table of content Preliminary Page Resumen i Abstract ii Übersetzung iii DECLARATION ix 1. Introduction 1 1.1. Plant-growth promoting microorganisms 1 1.2. Soil cyanobacteria 2 1.3. Physiology of soil cyanobacteria 2 1.4. Cyanobacterial plant growth-promoting molecules 4 1.5. Plant response to bioactive compounds 6 1.6. Cyanobacterial supernatants 9 1.7. Polypogon australis as a plant study model 11 2. Methodology 13 2.1. Obtention of the cyanobacterial cultures 13 2.2. Supernatant collection from the cyanobacterial cultures 14 2.3. Cyanobacterial biomass quantification 15 2.3.1. Chlorophyll-a content 15 2.3.2. Biomass dry weight 15 2.3.3. Determination of the growth phases 15 2.4. Chemical characterization of the supernatants 16 2.4.1. Nitrate content 16 2.4.2. Total element content 16 2.4.3. Zeatin content 16 2.5. Preparation of the modified BG-11 medium (BG-11M medium) 17 2.6. Bioassays with cyanobacterial supernatants 18 2.6.1. Effect of supernatants of the 25 mL cultures on P. australis germination 18 2.6.2. Effect of supernatants of the 25 mL cultures on P. australis plants 18 2.6.3. Effect of supernatants of the 2,400 mL cultures on P. australis plants 19 2.7. Statistical analysis 19 2.8. Determination of transcriptional changes in P. australis. 20 2.8.1. Plant treatments and tissue collection 20 2.8.2. Total RNA extraction from plant tissue 20 2.8.3. DNA removal 20 2.8.4. mRNA sequencing, de novo assembly, and differential expression analysis 21 2.8.5. Contig annotation and functional classification 22 3. Results 24 3.1. Trichormus sp. cultures produce the highest biomass content 24 3.2. Trichormus sp. cultures have a low P content 25 3.3. Trichormus sp. supernatants have the best growth-promoting effect on the growth of P. australis 25 3.4. Supernatant nutrient content of Trichormus sp. cultures change through the growth phases 27 3.5. Supernatants used in the transcriptomic assay and BG-11M medium have a lower nutrient content than BG-11 medium 30 3.6. Trichormus sp. supernatants promote the growth of P. australis to a greater extent than the BG-11M medium 32 3.7. Trichormus sp. supernatants contain zeatin 33 3.8. Trichormus sp. supernatants modulated more P. australis genes than the BG-11M medium 34 3.9. Trichormus sp. supernatants regulate the gene expression of growth and defense responses in P. australis 37 4. Discussion 57 4.1. The plant-growth promoting effect of Thrichormus sp. supernatants 57 4.2. The role of P and Mn in the growth-promoting effect of Trichormus sp. supernatants 58 4.3. Modulation of P. australis N-metabolism by Trichormus sp. supernatants 59 4.4. P. australis nitrogen and carbon metabolism in response to Trichormus supernatants 63 4.5. P. australis phytohormone-metabolism modulated by Trichormus supernatants 64 4.6. The role of lipid metabolism in the response to Trichormus supernatants 67 4.7. P. australis defense response triggered by Trichormus supernatants 68 4.8. Phytohormone crosstalk and defense response in P. australis treated with Trichormus sp. supernatants 71 4.9. Perspectives and challenges for the biotechnological use of Trichormus sp. supernatants 73 5. Conclusion 76 Bibliographic references 77 Annexes 116 / Los sobrenadantes de cianobacterias son prometedores productos promotores del crecimiento vegetal, pues contienen todas las ventajas de los compuestos bioactivos liberados, como fitohormonas, sin las limitaciones de las inoculaciones microbianas. Lamentablemente, poco se sabe sobre cómo las cianobacterias modularían la respuesta de las plantas a nivel molecular. En esta investigación, se utilizó la gramínea nativa chilena Polypogon australis como modelo para evaluar el efecto de sobrenadantes de cultivos de siete cianobacterias autóctonas de suelo. Los sobrenadantes de Trichormus sp. mostraron mejores efectos promotores del crecimiento de P. australis. Análisis mediante ICP-MS evidenciaron que estos sobrenadantes tenían un contenido nutricional similar al medio de crecimiento de las cianobacterias, BG-11, excepto por los elementos P y Mn, que se agotaron al alcanzarse la fase exponencial tardía de los cultivos. Para evaluar la respuesta de P. australis a nivel transcripcional, se emplearon sobrenadantes colectados en fase exponencial tardía de cultivos de Trichormus sp., que contenían una cantidad de 32,7 pmol de trans-zeatina por mg de Chl-a. Un medio BG-11 libre de P y Mn se utilizó como control. Tres horas después del tratamiento se recogió tejido de plantas completas y se le hizo un análisis de RNA-seq. Como resultado, los sobrenadantes principalmente modularon las vías de N y fitohormonas de la planta, en estrecha relación con los metabolismos de C y lípidos. Las plantas tratadas mostraron brotes más grandes que las plantas control, 4 y 8 días después de la aplicación, pero no se observaron diferencias en la longitud radicular. Este fenotipo puede explicarse por la inducción de biosíntesis de giberelina, apoyada por otras hormonas como auxinas, brasinoesteroides y etileno. Además, se observó una inducción de resistencia sistémica en las plantas tratadas, mediada por una interacción etileno-jasmonatos. Este trabajo corrobora el uso de sobrenadantes como una buena opción para promover el crecimiento de las plantas.:Table of content Preliminary Page Resumen i Abstract ii Übersetzung iii DECLARATION ix 1. Introduction 1 1.1. Plant-growth promoting microorganisms 1 1.2. Soil cyanobacteria 2 1.3. Physiology of soil cyanobacteria 2 1.4. Cyanobacterial plant growth-promoting molecules 4 1.5. Plant response to bioactive compounds 6 1.6. Cyanobacterial supernatants 9 1.7. Polypogon australis as a plant study model 11 2. Methodology 13 2.1. Obtention of the cyanobacterial cultures 13 2.2. Supernatant collection from the cyanobacterial cultures 14 2.3. Cyanobacterial biomass quantification 15 2.3.1. Chlorophyll-a content 15 2.3.2. Biomass dry weight 15 2.3.3. Determination of the growth phases 15 2.4. Chemical characterization of the supernatants 16 2.4.1. Nitrate content 16 2.4.2. Total element content 16 2.4.3. Zeatin content 16 2.5. Preparation of the modified BG-11 medium (BG-11M medium) 17 2.6. Bioassays with cyanobacterial supernatants 18 2.6.1. Effect of supernatants of the 25 mL cultures on P. australis germination 18 2.6.2. Effect of supernatants of the 25 mL cultures on P. australis plants 18 2.6.3. Effect of supernatants of the 2,400 mL cultures on P. australis plants 19 2.7. Statistical analysis 19 2.8. Determination of transcriptional changes in P. australis. 20 2.8.1. Plant treatments and tissue collection 20 2.8.2. Total RNA extraction from plant tissue 20 2.8.3. DNA removal 20 2.8.4. mRNA sequencing, de novo assembly, and differential expression analysis 21 2.8.5. Contig annotation and functional classification 22 3. Results 24 3.1. Trichormus sp. cultures produce the highest biomass content 24 3.2. Trichormus sp. cultures have a low P content 25 3.3. Trichormus sp. supernatants have the best growth-promoting effect on the growth of P. australis 25 3.4. Supernatant nutrient content of Trichormus sp. cultures change through the growth phases 27 3.5. Supernatants used in the transcriptomic assay and BG-11M medium have a lower nutrient content than BG-11 medium 30 3.6. Trichormus sp. supernatants promote the growth of P. australis to a greater extent than the BG-11M medium 32 3.7. Trichormus sp. supernatants contain zeatin 33 3.8. Trichormus sp. supernatants modulated more P. australis genes than the BG-11M medium 34 3.9. Trichormus sp. supernatants regulate the gene expression of growth and defense responses in P. australis 37 4. Discussion 57 4.1. The plant-growth promoting effect of Thrichormus sp. supernatants 57 4.2. The role of P and Mn in the growth-promoting effect of Trichormus sp. supernatants 58 4.3. Modulation of P. australis N-metabolism by Trichormus sp. supernatants 59 4.4. P. australis nitrogen and carbon metabolism in response to Trichormus supernatants 63 4.5. P. australis phytohormone-metabolism modulated by Trichormus supernatants 64 4.6. The role of lipid metabolism in the response to Trichormus supernatants 67 4.7. P. australis defense response triggered by Trichormus supernatants 68 4.8. Phytohormone crosstalk and defense response in P. australis treated with Trichormus sp. supernatants 71 4.9. Perspectives and challenges for the biotechnological use of Trichormus sp. supernatants 73 5. Conclusion 76 Bibliographic references 77 Annexes 116
38

Inoculation with Azospirillum brasilense associated with silicon applied to correct soil acidity and nitrogen rates in corn and wheat crops /

Galindo, Fernando Shintate. January 2020 (has links)
Orientador: Marcelo Carvalho Minhoto Teixeira Filho / Resumo: Alternative management practices are needed to minimize the need for chemical fertilizer use in non-leguminous cropping systems. The use of biological agents which can fix atmospheric nitrogen and promote plant growth has shown potential as an option to improve soil nutrient availability to grass crops. In recent years, studies investigating the effects of silicon (Si) have increased substantially, especially in grain crops. This increased interest in Si is likely due to the beneficial effects of Si application on plant resistance to abiotic and biotic stresses, reflecting on greater plant development. This research was developed to investigate if inoculation of corn and wheat with Azospirillum brasilense associated with Si can enhance nitrogen use efficiency (NUE) and improve plant nutrition and yield, leading to a greater economic profit. The study was set up in a Rhodic Haplustox under no-till system, located in Selvíria, state of Mato Grosso do Sul, Brazil. The field trial took place during the 2015/16 (November-March), 2016 (April-September), 2016/17 (November-March) and 2017 April-September) seasons, with corn and wheat crops in sucession (spring/summer and winter seasons for corn and wheat, respectively). Treatments were tested in a randomized completely block design with four replicates, arranged in a full factorial design 5 × 2 × 2 and included: i) five N application rates, as urea source, applied in side-dressing (0, 50, 100, 150 and 200 kg ha-1); ii) two liming sou... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor

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