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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.
41

Manejo do solo e consórcio de gramíneas ou leguminosas no desenvolvimento e produtividade do milho primeira safra e feijão de inverno em sucessão no sistema plantio direto no cerrado /

Takasu, Anderson Teruo. January 2019 (has links)
Orientador: Orivaldo Arf / Resumo: O uso de práticas conservacionistas como a consorciação do milho com gramíneas ou leguminosas é essencial para a sustentabilidade do sistema plantio direto, sendo fundamental a seleção de coberturas vegetais com elevada capacidade de produção de massa seca, visando à formação de palhada de maior persistência para proteção do solo e desenvolvimento das culturas em sucessão. Assim, objetivou-se avaliar os efeitos dos manejos de solo e semeadura do milho consorciado com gramíneas ou leguminosas nas características agronômicas e produtividade do milho na “primeira safra” em solo compactado, a persistência das coberturas vegetais do milho consorciado ou não e o cultivo do feijão de inverno em sucessão inoculado com Rhizobium tropici ou co-inoculado com Azospirillum brasilense no sistema plantio direto no Cerrado. O experimento foi desenvolvido nos anos agrícolas de 2015/16, 2016/17 e 2017/18, no município de Selvíria-MS. O delineamento experimental na cultura do milho foi em blocos casualizados, em esquema fatorial 2 x 5, sendo manejos de solo (sistema plantio direto e cultivo mínimo) e milho consorciado ou não (milho exclusivo; milho + Urochloa ruziziensis; milho + U. brizantha; milho + Crotalaria spectabilis e milho + guandu anão) e para a cultura do feijão de inverno no esquema fatorial 2 x 5 x 2, com dois manejos, cinco coberturas vegetais e dois inoculantes (Rhizobium tropici e R. tropici + Azospirillum brasilense). O consórcio do milho com leguminosas ou gramíneas, semeadas ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The use of conservation practices such as corn intercropping with grasses or legumes is essential for the sustainability of the no-tillage system, and being fundamental the selection of covers crops with high production capacity dry mass, aiming at the formation of straw of high persistence for soil protection and development of crops in succession. Thus, his study aimed to evaluate the effects of soil management and sowing of corn intercropped with grasses or legumes in the agronomic characteristics and corn productivity in the “first crop” in compacted soil, the persistence of the covers crops of corn intercropped or not and the cultivation of winter common bean in succession inoculated with Rhizobium tropici or co-inoculated with Azospirillum brasilense in the no-tillage system in the Cerrado. The experiment was developed in the agricultural years of 2015/16, 2016/17 and 2017/18, in the town of Selvíria, in the State of Mato Grosso do Sul - Brazil. The experimental design was a randomized block, , in a 2x5 factorial scheme, being soil management (no-tillage and minimum tillage) and corn intercropping or not (exclusive corn; corn + U.ruziziensis; corn + U. brizantha; corn + C. spectabilis and corn + Cajanus cajan) and for the winter common bean crop in the 2 x 5 x 2 factorial scheme with two managements, five covers crops and two inoculants (Rhizobium tropici e R. tropici + Azospirillum brasilense). The intercropping of corn with legumes or grasses, sown simultaneously betw... (Complete abstract click electronic access below) / Doutor
42

Co-inoculação de rhizobium e azospirillum e adubação nitrogenada na cultura do feijão comum / Co-inoculation of Rhizobium and Azospirillum and nitrogen fertilization in common bean

Gilabel, Amanda Prado 22 February 2018 (has links)
Submitted by AMANDA PRADO GILABEL null (apgilabel@gmail.com) on 2018-03-06T19:36:53Z No. of bitstreams: 1 DISSERTAÇÃO_Amanda Prado Gilabel_versão corrigida.pdf: 1797117 bytes, checksum: c7474d9d20943b0a7c765dea44b8e3a0 (MD5) / Approved for entry into archive by Maria Lucia Martins Frederico null (mlucia@fca.unesp.br) on 2018-03-06T19:52:42Z (GMT) No. of bitstreams: 1 gilabel_ap_me_botfca.pdf: 1655901 bytes, checksum: e1a13b445f08c0f1159626f286b077e2 (MD5) / Made available in DSpace on 2018-03-06T19:52:42Z (GMT). No. of bitstreams: 1 gilabel_ap_me_botfca.pdf: 1655901 bytes, checksum: e1a13b445f08c0f1159626f286b077e2 (MD5) Previous issue date: 2018-02-22 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Devido ao alto custo e baixa eficiência de aproveitamento dos fertilizantes nitrogenados pelas plantas, existe grande interesse em estratégias, como a fixação biológica de N2 (FBN), para a redução da aplicação de nitrogênio (N) inorgânico nas culturas. A co-inoculação consiste na combinação de bactérias do gênero Rhizobium (simbióticas) com as do gênero Azospirillum (associativas), aos quais podem produzir efeito sinérgico proporcionando resultados superiores àqueles obtidos quando utilizadas de forma isolada. O objetivo desse trabalho foi avaliar o efeito da co-inoculação com Rhizobium tropici e Azospirillum brasilense, bem como da adubação nitrogenada de semeadura, no crescimento, nodulação, nutrição mineral e produtividade de grãos do feijoeiro comum. Foram conduzidos dois experimentos em condições de campo, durante as safras "das águas” e “da seca” do ano agrícola 2016/2017; e um experimento em condições de casa de vegetação durante o período de janeiro a março de 2017, no município de Botucatu-SP. Em todos os experimentos, o delineamento utilizado foi em blocos casualizados, com quatro repetições. Foram estudadas nove formas de inoculação/co-inoculação e aplicação de N em cobertura [1: controle absoluto (sem inoculação e sem N em cobertura); 2: 60 kg ha-1 de N em cobertura em V4; 3: inoculação com R. tropici 2,5 × 106 células semente-1; 4: inoculação com A. brasilense 5,2 × 104 células semente-1; 5: inoculação com A. brasilense 2,5 × 105 células semente-1; 6: inoculação com A. brasilense 5,0 × 105 células semente-1; 7: co-inoculação R. tropici + A. brasilense 5,2 × 104 células semente-1; 8: co-inoculação R. tropici + A. brasilense 2,5 × 105 células semente-1; 9: co-inoculação R. tropici + A. brasilense 5,0 × 105 células semente-1], combinadas com a aplicação ou não de 20 kg ha-1 N na semeadura. Em condições de casa de vegetação, o fornecimento de N, em semeadura ou cobertura, reduziu o número e a matéria seca de nódulos e aumentou o teor e o acúmulo de N na parte aérea do feijoeiro. A aplicação de N na base proporcionou incrementos em termos de matéria seca de parte aérea, comprimento radicular e matéria seca de raízes do feijão comum. A inoculação apenas com A. brasilense, combinada com o fornecimento de N na semeadura incrementou o número de nódulos e, sem N na semeadura, proporcionou maior matéria seca de nódulos e teor de ureídos no feijão “das águas”. As co-inoculações com R. tropici + A. brasilense 2,5 × 105 células semente-1 e R. tropici + A. brasilense 5,2 × 104 células semente-1 combinadas com adição de 20 kg ha-1 de N na semeadura aumentaram a matéria seca de nódulos e teor de ureídos do feijoeiro comum na safra “das águas”. A adição de N na semeadura incrementou os teores foliares de Ca e Mg, área foliar e matéria seca de parte aérea e reduziu o teor de N na parte aérea do feijoeiro. O fornecimento de N em cobertura aumentou o teor foliar de Zn e reduziu o índice relativo de clorofila. A aplicação de N em cobertura, com ou sem a adição do nutriente na base, aumentou o comprimento e a superfície radicular. Apesar da discrepância entre alguns tratamentos, as formas de inoculação/co-inoculação e aplicação de N em cobertura não afetaram significativamente a produtividade de grãos do feijoeiro comum cultivado em sistema de semeadura direta. / Due to the high cost and low use efficiency of nitrogen (N) fertilizers by plants, there is great interest in strategies to reduce N application in crops, such as biological N2 fixation (BNF). Co-inoculation consists in combination of bacteria of the genus Rhizobium (symbiotics) with those of the genus Azospirillum (associatives), which can produce a synergistic effect, providing higher performance of the plants then those obtained using Rhizobium alone. The aim of this study was to evaluate the effect of co-inoculation with Rhizobium tropici and Azospirillum brasilense, as well as N fertilization at sowing, in growth, nodulation, mineral nutrition, and grain yield of common bean. Two experiments were conducted under field conditions in “spring” and “summer-fall” growing seasons of the 2016/2017 harvest, and an experiment under greenhouse conditions during the period from January to March of 2017, in Botucatu-SP, Brazil. In all experiments, the design was in randomized blocks, with four replications. Nine forms of inoculation/co-inoculation and topdressing N application were studied [1: absolute control (without inoculation and without topdressing N ) 2: 60 kg ha-1 of topdressing N in V4; 3: inoculation with R. tropici 2.5 × 106 cells seed-1; 4: inoculation with A. brasilense 5.2 × 104 cells seed-1; 5: inoculation with A. brasilense 2.5 × 105 cells seed-1; 6: inoculation with A. brasilense 5.0 × 105 cells seed-1; 7: co-inoculation R. tropici + A. brasilense 5.2 × 104 cells seed-1; 8: co-inoculation R. tropici + A. brasilense 2.5 × 105 cells seed-1; 9: co-inoculation R. tropici + A. brasilense 5.0 × 105 cells seed-1], combined with the application or not of 20 kg ha-1 of N at sowing furrow. Under greenhouse conditions, the N supply at sowing or topdressing reduced the number and dry matter of nodules and increased N concentration and accumulation in the common bean shoot. Nitrogen application at sowing provided increases in shoot dry matter, root length and root dry matter of common bean. The inoculation with A. brasilense alone, combined with the N supply at sowing increased the number of nodules and without N at sowing provided higher dry matter of nodules and ureides content in "spring" growing season. Co-inoculations with R. tropici + A. brasilense 2.5 × 105 cells seed-1 and R. tropici + A. brasilense 5.2 × 104 cells seed-1 combined with the application of 20 kg ha-1 of N at sowing increased dry matter of nodules and ureides content of common bean in "spring" growing season. Addition of N at sowing increased the leaf concentrations of Ca and Mg, leaf area, and shoot dry matter and reduced the N concentration in the common bean shoot. Topdressing N application increased the leaf concentration of Zn and reduced the chlorophyll relative index. Topdressing N application, with or without N application at sowing furrow, increased the root length and surface. In spite of the discrepancy between some treatments, the inoculation/co-inoculation forms and topdressing N application did not affect significantly the grain yield of the common bean cultivated under a no-tillage system. / FAPESP: 2016/07591-2
43

Atributos agronômicos e qualitativos de cultivares de feijoeiro-comum sob monitoramento e manejos de fornecimento de nitrogênio utilizando clorofilômetro portátil /

Filla, Vinicius Augusto. January 2019 (has links)
Orientador: Leandro Borges Lemos / Resumo: Práticas mais sustentáveis envolvendo a fixação biológica de nitrogênio (FBN) e o uso do clorofilômetro portátil no manejo da adubação têm se mostrado promissoras para aumentar a eficiência do uso de nitrogênio (N) na cultura do feijoeiro-comum. Objetivou-se monitorar manejos de fornecimento de N com o uso do clorofilômetro portátil e avaliar seus efeitos nos atributos agronômicos e qualitativos de cultivares de feijoeiro-comum do tipo carioca de crescimento indeterminado e determinado (IPR Campos Gerais e IAC Imperador). O experimento foi implantado no delineamento em blocos casualizados (DBC), no esquema fatorial 2 x 9, com quatro repetições. O primeiro fator foi constituído pelas cultivares e o segundo fator pelos seguintes manejos de fornecimento de N: MT: Testemunha sem inoculação e sem adubação de N em cobertura; MRiz: Testemunha inoculada com Rhizobium tropici e sem aplicação de N em cobertura; MRiz+Clo: Inoculação com Rhizobium tropici + 30 kg ha-1 de N quando o índice de suficiência de N (ISN) determinado com o uso do clorofilômetro portátil for inferior a 90%; MRiz+Clo+Azo: Inoculação com Rhizobium tropici + de 30 kg ha-1 de N quando ISN < 90% + aplicação de Azospirillum brasilense via foliar (V4); MClo: 30 kg ha-1 de N quando ISN < 90%; M45: 45 kg ha-1 de N em V4; M90: 90 kg ha-1 de N em V4; M135: 135 kg ha-1 de N em V4; MRef: 90 kg ha-1 de N em V3 + 90 kg ha-1 de N em V4. Realizou-se o monitoramento do índice de clorofila e a avaliação dos teores de N foliar ao lo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: More sustainable practices involving biological nitrogen fixation (BNF) and the use of portable chlorophyll meter in fertilization management are promising to increase nitrogen (N) use efficiency in the common bean crop. This study aimed to monitor N supply managements using a portable chlorophyll meter and its effects on agronomic and qualitative attributes of Carioca-type common bean cultivars with indeterminate and determinate growth habits (IPR Campos Gerais and IAC Imperador). The experiment was carried out in a randomized block design (RBD), in a 2 x 9 factorial scheme, with four replicates. The first factor consisted of the cultivars and the second factor for the following N supply managements: MC: Control without inoculation and without top-dressing N fertilization; MRhz: Control inoculated with R. tropici and without top-dressing N fertilization; MRhz+Chl: Rhizobium tropici inoculation + 30 kg ha-1 of N when the N sufficiency index (NSI) determined using the portable chlorophyll meter is less than 90%; MRhz+Chl+Azo: Rhizobium tropici inoculation + 30 kg ha-1 of N when NSI < 90% + foliar application of Azospirillum brasilense (V4); MChl: 30 kg ha-1 of N when NSI < 90%; M45: 45 kg ha-1 of N in V4; M90: 90 kg ha-1 of N in V4; M135: 135 kg ha-1 of N in V4; MRef: 90 kg ha-1 of N in V3 + 90 kg ha-1 of N in V4. The chlorophyll index was monitored, and leaf N levels were evaluated throughout the cycle, shoot dry matter determination, yield components, yield and qualitative a... (Complete abstract click electronic access below) / Mestre
44

Leguminosas em consórcio com milho segunda safra e o seu efeito no manejo do nitrogênio na soja e arroz de terras altas cultivados em sucessão / Leguminous in intercroping with second cultivation corn and its effect on nitrogen management in soy and rice of upland cultivated successions

Gerlach, Gustavo Antonio Xavier 22 December 2017 (has links)
Submitted by Gustavo Antonio Xavier Gerlach null (g.gerlach@agr.feis.unesp.br) on 2018-01-08T11:09:12Z No. of bitstreams: 1 Tese_Final.pdf: 1712184 bytes, checksum: 3b5ce3c1c6152a91faa766f1d91d091b (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-01-08T13:54:43Z (GMT) No. of bitstreams: 1 gerlach_gax_dr_ilha.pdf: 1660405 bytes, checksum: 4a0a30a19f551993f90754ea19b9b7ab (MD5) / Made available in DSpace on 2018-01-08T13:54:43Z (GMT). No. of bitstreams: 1 gerlach_gax_dr_ilha.pdf: 1660405 bytes, checksum: 4a0a30a19f551993f90754ea19b9b7ab (MD5) Previous issue date: 2017-12-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As elevadas taxas de decomposição do material orgânico em regiões tropicais tem sido um dos problemas para a manutenção e sustentabilidade do sistema plantio direto, isso devido à necessidade de produção de grandes quantidades de palha e a imobilização do nitrogênio no sistema de plantio direto. O cultivo intercalar de adubos verdes na cultura do milho pode produzir maior quantidade de matéria seca de plantas do que em culturas solteiras. Nessa condição o consórcio de culturas constitui alternativa para suprir o aporte anual de palha e fornecer nitrogênio às culturas. Dependendo da relação C/N da palhada que tem-se área poderá ocorrer menor disponibilidade de nitrogênio para a cultura da soja o cultivo de leguminosas com a cultura do milho poderá suprir essa deficiência de nitrogênio devido a maior fixação de nitrogênio. Na cultura do arroz com a inoculação de Azospirillum brasilense conseguira aproveitar o nitrogênio na área havendo economia de fertilizantes nitrogenados. Assim, o objetivo do trabalho é o de estudar o efeito de leguminosas em consórcio com a cultura do milho 2ª safra para a produção de matéria seca com relação C/N intermediaria e posteriormente verificar o seu efeito no fornecimento de nitrogênio para a cultura da soja com e sem adubação nitrogenada e o maior aproveitamento do nitrogênio para a cultura do arroz de terras altas com e sem inoculação de Azospirillum brasilense. O trabalho foi constituído por três subprojetos e desenvolvido na Fazenda experimental da UNESP – Campus de Ilha Solteira. O delineamento experimental utilizado foi o de blocos ao acaso com 4 repetições e 10 tratamentos constituídos pela combinação do efeito dos restos culturais de milho, estilosantes, guandu e Crotalaria spectabilis. O delineamento experimental para a soja e arroz em sucessão ao milho foi o de blocos ao acaso em esquema fatorial 10x2 com os tratamentos constituídos pelos restos culturais do milho e adubos verdes e presença e ausência de adubação nitrogenada em semeadura para a cultura da Soja e de presença e ausência de inoculação com Azospirillum brasilense para a cultura do arroz. Concluiu-se que o consórcio com os adubos verdes não interferiu na produtividade do milho e há incremento da matéria seca total após a colheita do milho e redução da relação C/N nos tratamentos consorciados; o consórcio de milho com leguminosas a inoculação com Azospirillum brasilense e a ausência de nitrogênio na semeadura influenciaram a produtividade do arroz; e os componentes de produção e a produtividade da soja respectivamente. Os maiores retornos financeiros foram observados pelos consórcios de milho com estilosantes e milho com guandu em semeadura simultânea, e pela inoculação de Azospirillum brasilense em arroz e ausência de nitrogênio mineral na semeadura da soja / The high rates of decomposition of organic material in tropical regions has been one of the problems for the maintenance and sustainability of the no-tillage system, due to the need to produce large amounts of straw and nitrogen immobilization in the no-tillage system. The intercropping of green manure in maize can produce more dry matter than in single crops. In this condition the crop consortium is a alternative to supply the annual straw supply and supply nitrogen to crops. Depending on the C/N ratio of the straw that has an area, there may be less nitrogen availability for the soybean crop. The cultivation of legumes with the maize crop can supply this nitrogen deficiency due to the greater nitrogen fixation. In rice cultivation with the inoculation of Azospirillum brasilense it was able to take advantage of the nitrogen in the area, with nitrogen fertilizer economy. Thus, the objective of this work was to study the effect of legumes in intercropping with maize crop 2 nd crop for dry matter production with intermediate C/N ratio and later to verify its effect on the nitrogen supply to the soybean crop with and without nitrogen fertilization and the greater use of nitrogen for upland rice cultivation with and without inoculation of Azospirillum brasilense. The research is made up of three subprojects and was developed at the experimental farm of UNESP - Ilha Solteira Campus. The experimental design was a randomized complete block design with 4 replicates and 10 treatments consisting of the effect of the cultural remains of maize, estilosantes, Pigeon pea and Crotalaria spectabilis. The experimental design for soybean and rice in succession to maize will be a randomized block design in a 10x2 factorial scheme with the treatments constituted by maize and green manure crop residues and the presence and absence of nitrogen fertilization in sowing for Soja and presence and absence of inoculation with Azospirillum brasilense for rice cultivation. It was concluded that the intercropping with the green manures did not interfere in the maize productivity and there was an increase in total dry matter after maize harvest and reduction of the C/N ratio of the intercropping treatments; The maize and legume consortium inoculation with Azospirillum brasilense and the absence of nitrogen at sowing influenced rice yield; and the production components and yield of soybean respectively. The highest financial returns was observed in maize intercropping with stylers and pigeon pea in simultaneous sowing and by the inoculation of Azospirillum brasilense in rice and absence of mineral nitrogen in soybean sowing
45

Leguminosas em consórcio com milho segunda safra e o seu efeito no manejo do nitrogênio na soja e arroz de terras altas cultivados em sucessão /

Gerlach, Gustavo Antonio Xavier. January 2017 (has links)
Orientador: Orivaldo Arf / Resumo: As elevadas taxas de decomposição do material orgânico em regiões tropicais tem sido um dos problemas para a manutenção e sustentabilidade do sistema plantio direto, isso devido à necessidade de produção de grandes quantidades de palha e a imobilização do nitrogênio no sistema de plantio direto. O cultivo intercalar de adubos verdes na cultura do milho pode produzir maior quantidade de matéria seca de plantas do que em culturas solteiras. Nessa condição o consórcio de culturas constitui alternativa para suprir o aporte anual de palha e fornecer nitrogênio às culturas. Dependendo da relação C/N da palhada que tem-se área poderá ocorrer menor disponibilidade de nitrogênio para a cultura da soja o cultivo de leguminosas com a cultura do milho poderá suprir essa deficiência de nitrogênio devido a maior fixação de nitrogênio. Na cultura do arroz com a inoculação de Azospirillum brasilense conseguira aproveitar o nitrogênio na área havendo economia de fertilizantes nitrogenados. Assim, o objetivo do trabalho é o de estudar o efeito de leguminosas em consórcio com a cultura do milho 2ª safra para a produção de matéria seca com relação C/N intermediaria e posteriormente verificar o seu efeito no fornecimento de nitrogênio para a cultura da soja com e sem adubação nitrogenada e o maior aproveitamento do nitrogênio para a cultura do arroz de terras altas com e sem inoculação de Azospirillum brasilense. O trabalho foi constituído por três subprojetos e desenvolvido na Fazenda experiment... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The high rates of decomposition of organic material in tropical regions has been one of the problems for the maintenance and sustainability of the no-tillage system, due to the need to produce large amounts of straw and nitrogen immobilization in the no-tillage system. The intercropping of green manure in maize can produce more dry matter than in single crops. In this condition the crop consortium is a alternative to supply the annual straw supply and supply nitrogen to crops. Depending on the C/N ratio of the straw that has an area, there may be less nitrogen availability for the soybean crop. The cultivation of legumes with the maize crop can supply this nitrogen deficiency due to the greater nitrogen fixation. In rice cultivation with the inoculation of Azospirillum brasilense it was able to take advantage of the nitrogen in the area, with nitrogen fertilizer economy. Thus, the objective of this work was to study the effect of legumes in intercropping with maize crop 2 nd crop for dry matter production with intermediate C/N ratio and later to verify its effect on the nitrogen supply to the soybean crop with and without nitrogen fertilization and the greater use of nitrogen for upland rice cultivation with and without inoculation of Azospirillum brasilense. The research is made up of three subprojects and was developed at the experimental farm of UNESP - Ilha Solteira Campus. The experimental design was a randomized complete block design with 4 replicates and 10 treatments ... (Complete abstract click electronic access below) / Doutor
46

Caractérisations biochimique et microscopique du piège extracellulaire de racine et des exsudats racinaires de trois essences ligneuses sahéliennes : balanites aegyptiaca D., Acacia tortilis subsp. raddiana S., et tamarindus indica L / Biochemical and microscopic characterization of the root extracellular root trap and root exudates of three Sahelian woody seedlings : Balanites aegyptiaca D., Acacia tortilis subsp. raddiana S. and Tamarundus indica L.

Carreras, Alexis 28 March 2018 (has links)
La coiffe racinaire est cruciale à la croissance et survie du méristème subapical de racine. Elle libère des cellules frontières (CFs) qui assurent la protection de l’apex racinaire. Les CFs associées à leur mucilage forment le piège extracellaire de racine (RET). La caractérisation du RET et des exsudats racinaires de trois essences ligneuses sahéliennes à partir de plantules cultivées in vitro a été réalisée. B. aegyptiaca et A. raddiana prospèrent dans les zones semi-arides, à l’opposé de T. indica. La morphologie des CFs et l’organisation du RET ont été déterminées par microscopie. La compostion en glycopolymères et la détection des arabinogalactanes proteines (AGPs) dans le RET et les exsudats racinaires ont été déterminées par des analyses biochimiques. L’effet des exsudats racinaires sur la croissance d’Azospirillum brasilense, une bactérie bénéfique pour la plante a été évalué. B. aegyptiaca produit des CFs de type border cells (BCs) alors que les autres Fabaceae produisent des BCs et des border-like cells. Les BCs sont entourées d’un dense mucilage riche en polymères de paroi. Le RET et les exsudats racinaires issus de B. aegyptiaca et A. raddiana sont plus riches en AGPs que ceux provenant T. indica. Les AGPs pourraient contribuer à la survie des plantules dans un contexte semiaride. Ce travail ouvre de nouvelles perspectives de recherche concernant l'implication du RET dans la survie des plantes à l'aridité. / The root cap is primordial for seedling growth and supports root apical meristem integrity. The root cap releases root border cells (RBCs) that surround the root tip and ensure seedling protection against numerous stresses. RBCs and their associated mucilage form the root extracellular trap (RET). Here, RET and root exudate characterization of three Sahelian woody seedlings are performed. In contrast to B. aegyptiaca and A. raddiana which thrive in semi-arid areas, T. indica is more sensitive to drought. B. aegyptiaca, A. raddiana and T. indica seedlings were sub-cultured in vitro. RBC morphologies and RET organization were determined using microscopic approaches. The polysaccharide composition and arabinogalactan protein (AGP) content were determined by biochemical approaches in the RET and the root exudates. Moreover, the effect of root exudates on the growth of Azospirillum brasilense a plant benefical bacteria has been performed. While B. aegyptiaca produces only border cell (BC) type, the two Fabaceae seedlings release both BCs and border-like cells (BLCs). BCs are enclosed in a dense mucilage enriched in cell wall polymers. Compared to T. indica, RET and root exudates of B. aegyptiaca and A. raddiana include more abundant AGPs. In this context, AGPs could contribute to woody seedling survival. This work opens new research perspectives regarding involvement of RET in plant survival to aridity.
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MICRORGANISMOS SIMBIONTES, MATÉRIA ORGÂNICA E ADUBAÇÃO NITROGENADA NO DESENVOLVIMENTO E NUTRIÇÃO DO MIRTILEIRO CV. CLIMAX EM AMBIENTE PROTEGIDO

Santana, Kamila 24 June 2016 (has links)
Made available in DSpace on 2017-07-25T19:31:00Z (GMT). No. of bitstreams: 1 Kamila Santana.pdf: 1363071 bytes, checksum: 4f5da813f22ced41d3b26851a927779f (MD5) Previous issue date: 2016-06-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The blueberry is an agricultural crops recently introduced in Brazil and lots of researches are turning to develop and adapt it to the country. Due to its low amount of root hair, it forms associations with microorganisms to expand its zone of nutrient uptake, being the nitrogen the most required element. At this work it was observed the interaction of this cultivation with the inoculum Azospirilum brasilense and Trichodema asperellum into different substrates or doses of nitrogen fertilization. The experiment was performed with cv. Climax and the plants conditioned in pots in greenhouse, under trial design of randomized blocks, factorial 3x3. The considered factors were inoculation (A. brasilense, T. asperellum or without inoculation) and formulation of the substrates (5; 20 e 35% of organic matter – hardened cattle manure) or, at the second experiment, inoculation (A. brasilense, T. asperellum or without inoculation) and doses of nitrogen (0, 10 and 15 g f N plant-1 – provided as urea). The larger quantity of organic matter provided the highest averages relating to physiological (transpiration, water use efficiency and carboxylation efficiency) and growth variables (foliar limb area, total foliar area and rate of relative growth), although, for some of them, it has not differed from plants grown with 20% of organic matter. With 30% of O.M., the inoculation with T. asperellum showed superior averages in CO2 assimilation (A), carboxylation efficiency (A/Ci) and rate of relative growth (RRG). The nitrogen doses positively affected A/Ci, clorophyll amounts, foliar area (limb and total) and foliar nitrogen concentration, although it not differing between 10 or 15g of N plant-1. For the accumulation of the nutrients Ca, Mg, S, Fe and Zn, the nitrogen fertilization did not represent higher foliar levels, even though this might be related to a dilution effect. / O mirtileiro é uma cultura recentemente introduzida no Brasil, sendo que várias pesquisas tem-se voltado para seu melhor desenvolvimento e adaptação no país. Por possuir poucos pelos radiculares, forma associações com microrganismos afim de aumentar sua zona de absorção de nutrientes, sendo o nitrogênio o elemento absorvido em maior quantidade. Neste trabalho, observou-se a interação dessa cultura com os inóculos Azospirillum brasilense e Trichoderma asperellum em diferentes substratos ou doses de adubação nitrogenada. O experimento foi realizado com a cv. Clímax e as plantas acondicionadas em vasos, em casa de vegetação, sob delineamento experimental de blocos casualizados em esquema fatorial 3x3. Os fatores analisados foram inoculação (A. brasilense, T. asperellum ou sem inoculação) e formulação dos substratos (5; 20 e 35% de matéria orgânica – esterco bovino curtido) ou, no segundo experimento, inoculação (A. brasilense, T. asperellum ou sem inoculação) e doses de nitrogênio (0, 10 e 15 g de N planta-1 – fornecido como ureia). A maior proporção de matéria orgânica propiciou as maiores médias em relação a variáveis fisiológicas (transpiração, eficiência no uso da água e eficiência de carboxilação) e de crescimento (área de limbo foliar, área foliar total e taxa de crescimento relativo), embora, para outras, não tenha diferido das plantas cultivadas com 20% de matéria orgânica. Com 35% de M.O., a inoculação com T. asperellum apresentou médias superiores em assimilação de CO2 (A), eficiência de carboxilação (A/Ci) e taxa de crescimento relativo (TCR). As doses de nitrogênio influenciaram positivamente A/Ci, teores de clorofila, área foliar (de limbo e total) e concentração foliar de nitrogênio, embora não diferindo entre 10 ou 15g de N planta-1. Para o acúmulo dos nutrientes Ca, Mg, S, Fe e Zn, a adubação nitrogenada não representou maiores teores foliares, embora isto possa estar relacionado a um efeito de diluição.
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Μεταβολές του αζώτου στο έδαφος και την καλλιέργεια γλυκού σόργου (Sorghum bicolor (L) Moench)

Κουβέλας, Αντώνης 24 January 2011 (has links)
Σκοπός της παρούσας διδακτορικής διατριβής ήταν η μελέτη της δυναμικής του αζώτου σε καλλιέργεια γλυκού σόργου. Χρησιμοποιήθηκαν φυτά γλυκού σόργου [Sorghum bicolor (L) Moench] ποικιλίας Keller και πραγματοποιήθηκαν αφ’ ενός πειράματα στο πεδίο αφ’ ετέρου πειράματα σε πλαστικά δοχεία. Τα πειράματα πεδίου πραγματοποιήθηκαν σε αγρόκτημα του Πανεπιστημίου Πατρών, τις καλλιεργητικές περιόδους του 2004 και 2005, και περιλάμβαναν δύο χειρισμούς (βιολογική και συμβατική διαχείριση της γονιμότητας του εδάφους), με τρεις επαναλήψεις ο καθένας σε πλήρη τυχαιοποιημένη διάταξη. Τα αποτελέσματα των πειραμάτων πεδίου, έδειξαν ότι η βιολογική διαχείριση της γονιμότητας του εδάφους ευνόησε τη διαθεσιμότητα του εδαφικού νιτρικού αζώτου. Το 2004, μέχρι και την ολοκλήρωση της άνθησης, τα φυτά του βιολογικού χειρισμού συσσώρευσαν περισσότερο άζωτο από ό,τι τα φυτά του συμβατικού χειρισμού, αν και οι διαφορές δεν ήταν στατιστικά σημαντικές, εκτός από τη δεύτερη δειγματοληψία, όπου τα φυτά του συμβατικού χειρισμού συσσώρευσαν 2,69 N gm-2, ενώ για τα φυτά του βιολογικού χειρισμού η αντίστοιχη τιμή ήταν 5,12 N gm-2. Το 2005, η συσσώρευση αζώτου ακολούθησε παρόμοια πορεία μέχρι τα μέσα της άνθησης και οι διαφορές δεν ήταν στατιστικά σημαντικές, εκτός από τη τρίτη δειγματοληψία, όπου τα φυτά του συμβατικού χειρισμού συσσώρευσαν 3,61 N gm-2, ενώ για τα φυτά του βιολογικού χειρισμού η αντίστοιχη τιμή ήταν 4,61 N gm-2. H επίδραση εμβολίων Azospirillum brasilense, σε παραμέτρους αύξησης φυτών γλυκού σόργου και στην πρόσληψη αζώτου από τα φυτά, υπό διαφορετικά επίπεδα αζωτούχου λίπανσης μελετήθηκε σε πειράματα σε πλαστικά δοχεία. Το κάθε πείραμα περιλάμβανε πέντε χειρισμούς με τριάντα επαναλήψεις, έκαστος. Τα φυτά που εμβολιάστηκαν με Azospirillum brasilense και έλαβαν τη μισή ποσότητα αζώτου, έδωσαν 7,69 g ξηρής βιομάζας φυτό-1 στο τέλος του πρώτου πειράματος και 4,89 g ξηρής βιομάζας φυτό-1 στο τέλος του δεύτερου πειράματος, ενώ τα φυτά που δέχθηκαν πλήρη λίπανση αζώτου χωρίς εμβόλιο έδωσαν 2,39 και 2,04 g ξηρής βιομάζας φυτό-1 στο τέλος του πρώτου και δεύτερου πειράματος αντιστοίχως. Οι διαφορές των χειρισμών ανά πείραμα ήταν στατιστικά σημαντικές. Το συνολικό προσλαμβανόμενο άζωτο από τα φυτά που εμβολιάστηκαν με Azospirillum brasilense και έλαβαν τη μισή ποσότητα αζώτου ήταν 153,23 και 99,96 mg φυτό-1 στο τέλος του πρώτου και του δεύτερου πειράματος αντιστοίχως. Οι τιμές ήταν υψηλότερες σε σχέση με τις τιμές του συνολικού προσλαμβανόμενου αζώτου των φυτών των λοιπών και οι διαφορές ήταν στατιστικά σημαντικές. Τα αποτελέσματα των πειραμάτων έδειξαν υψηλή αξιοποίηση του εφαρμοζόμενου αζώτου των φυτών που εμβολιάστηκαν με Azospirillum. Τα αποτελέσματα υποδεικνύουν την βιωσιμότητα ενός βιολογικού συστήματος καλλιέργειας, όσον αφορά την κάλυψη των αναγκών των φυτών σε άζωτο. Η υψηλή αξιοποίηση του αζώτου από τα φυτά γλυκού σόργου, οδηγεί στη μείωση εφαρμογής αζωτούχων λιπασμάτων και συμβάλλει στη μείωση του κόστους καλλιέργειας, στη μείωση εκπομπών αερίων του θερμοκηπίου και στην μείωση διήθησης νιτρικών στο υπόγειο υδροφόρο ορίζοντα. / The aim of the present thesis was to study the nitrogen dynamics in sweet sorghum crop. Sweet sorghum plants [Sorghum bicolor (L) Moench] variety Keller were used, and field and experiments were conducted. Field experiments were conducted during 2004 and 2005 growing seasons at the experimental station of the University of Patras, Greece and there were two treatments (biological and conventional soil fertility treatment), in a randomized complete block experimental design with three replications. The results showed that biological soil fertility treatment favour soil nitrate nitrogen concentration. In 2004, until completion of blooming, nitrogen uptake was higher in plants cultivated on biological fertility treated soil than in them cultivated on conventional but the differences were not statistically significant, except in second sampling, which nitrogen uptake was 2,69 N gm-2 in plants cultivated on conventional fertility treated soil and it was 5,12 N gm-2 in plants cultivated on conventional fertility treated soil. In 2005, until half of blooming, nitrogen uptake was similarly ranged for both treatments but the differences were not statistically significant, except in third sampling, which nitrogen uptake was 3,61 N gm-2 in plants cultivated on conventional fertility treated soil and it was 4,61 N gm-2 in plants cultivated on conventional fertility treated soil. Τhe effect of Azospirillum brasilense inoculation on growth parameters and nitrogen uptake in sweet sorghum plants fertilized with various nitrogen levels, was studied during pot experiments. Each experiment was including five treatments and thirty replications of each. Plants inoculated with Azospirillum brasilense and receiving half amount of nitrogen fertilizer produced 7,69 g dry biomass plant-1 at the end of the first experiment and they produced 4,89 at the end of the second one, while plants receiving full amount of nitrogen fertilizer and no inoculation produced 2,39 and 2,04 g dry biomass plant-1 at the end of the first and second experiment, respectively. Differences among treatments in each experiment, were statistically significant. Total nitrogen uptake in Plants inoculated with Azospirillum brasilense and receiving half amount of nitrogen fertilizer was 153,23 and it was 99,96 mg plant-1 at the end of first and second experiment, respectively. Those plants showed higher nitrogen uptake than plants from each other treatment and the differences were statistically significant. Results showed that treatments which inoculated with Azospirillum brasilense were the most efficient in terms of nitrogen uptake. These results indicate that biological management provides an adequate nitrogen nutrition to sweet sorghum crop. High nitrogen efficiency in sweet sorghum plants leads in reduced applying nitrogen fertilization and contribute in reduced crop cost, in reduced emission of the greenhouse gas and in reduced leaching of NO3-N to ground water.

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