Efeito de diferentes concentrações e estirpes da bactéria Azospirillum brasilense nos componentes de produção em plantas de trigo
Carregando...
Arquivos
Data
2016-09-02
Autores
Repke, Rodrigo Alberto [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
O triticum aestivum é uma espécie de ciclo anual, pertencente à família Poaceae. Cultivado em regiões de climas subtropical e temperado, ocupa a segunda maior área plantada no mundo. Para obtenção de altas produtividade dentre outros cuidados, é essencial o fornecimento de nutrientes na quantidade demandada pelas cultivares de alto potencial produtivo, com destaque para o nitrogênio (N). A fixação biológica de nitrogênio é realizada por microrganismos simbióticos associados com raízes das plantas. Entre os microrganismos simbióticos que fixam nitrogênio associados com raízes de plantas, destacam-se os do gênero Azospirillum brasilense. O objetivo no presente trabalho foi avaliar a eficiência do uso da inoculação Azospirillum brasilense no desenvolvimento e componentes produtivos da cultura do trigo. O estudo foi dividido em dois experimentos sendo o primeiro em ambiente protegido e o segundo em ambiente não protegido, ambos na Faculdade de Ciências Agronômicas - Universidade Estadual Paulista “Júlio de Mesquita Filho”, Campus de Botucatu, SP, no ano agrícola 2013. O delineamento utilizado foi o de blocos inteiramente casualizados para ambiente protegido e blocos casualizados para ambiente não protegido, com 10 tratamentos em esquema fatorial 3x3+1. Sendo os tratamentos compostos pelo uso de duas estirpes (Ab-V5 e Ab-V6) isoladamente e em combinação das mesmas (Ab-V5+Ab-V6), todos aplicados em três concentrações 65, 130 e 195 milhões de unidades formadoras de colônia (UFC) de bactérias. Mais a testemunha, sem inoculação de bactérias. Para o experimento em ambiente protegido, cada parcela experimental foi constituída por plantas cultivadas em um recipiente de amianto com capacidade para 0,462 m3 de solo. Foram 7 linhas de 0,88 m cada, espaçadas em 0,15 m, com 40 sementes por metro. Já no experimento em ambiente não protegido, a parcela experimental foi composta por 10 linhas de 2,0 m cada, espaçadas em 0,17 m, e 45 sementes por metro, onde ambos os experimentos teve uma densidade de semeadura em 266 sementes m2 almejando uma densidade de 250 plantas m2. Para atender a necessidade de água da cultura durante todo o ciclo, adotou-se o sistema de irrigação localizada por gotejamento, monitorada por tensiômetros de mercúrio. Após a emergência das plântulas até a colheita, foram realizadas avaliações de crescimento em diversos componentes morfológicos e de produtividade das plantas de trigo. Os dados obtidos foram submetidas à análise de variância pelo teste F a 5% de probabilidade, sendo os dados quantitativos submetidos a análise de regressão em função das doses de A.brasiliense os dados qualitativos em função das estirpes pelo teste de Tukey. Em ambiente protegido, a inoculação das sementes com Azospirillum brasilense promove maior crescimento das plantas de trigo, sem influencia na produção de grãos. Em condições de ambiente não protegido o crescimento das plantas é influenciado pela inoculação de Azospirillum brasilense. O uso de bactérias promotoras de crescimento em plantas aumentam o desenvolvimento das plantas de trigo, o que representa uma estratégia viável, além dos benefícios ambientais associados à redução no uso de fertilizantes nitrogenados.
Triticum aestivum is a yearly crop species belonging to the Poaceae family. It is cultivated in regions with subtropical and temperate climate, and takes up the second largest planted area in the world. Nutrient provision in the demanded amount by high productive potential cultivars, mainly nitrogen (N), is essential to obtain high productivity. The biological fixation of nitrogen is done by symbiotic microorganisms associated with plan roots. Azospirillum brasilense is one of the genera in which the symbiotic microorganisms fixate nitrogen associated with plant roots. This study aimed to evaluate the agronomical efficiency of Azospirillum brasilense inoculation on the growth and productive components of wheat cultivation. The study was divided into two experiments: the fist protected environment, and the second non-protected environment conditions, both in the School of Agriculture - Universidade Estadual Paulista “Júlio de Mesquita Filho”, Campus of Botucatu, SP, Brazil, during 2013 crop year. The experiment had completely randomized block design for the fist experiment in protected environment, and random blocks for the second experiment in non-protected environment, with 10 treatments in 3x3+1 factorial scheme. The treatments consisted of two separate (V5 and V6) and combined (V5+V6) stocks and three concentrations (65, 130 and 195 million UFC of bacteria) were applied. The control treatment had no bacterial inoculation. For the protected environment, each experimental plot consisted of plants cultivated in an asbestos recipient with the following dimensions: 0.50 m of height, 0.88 m of width and 1.05 m of length, and 0.462 m3 of soil. Seven 0.88-m rows with 0.15 m spacing and 40 seeds per meter were utilized. In the field experiment, the experimental plot consisted of ten 2.0-m rows with 0.17 m spacing and 45 seeds per meter. For both experiments, the seeding density was 266 seeds m2, aiming a density of 250 plants m2. To meet water cultivation requirements throughout the cycle, dripping irrigation was used and monitored by mercury tensiometers. After seedling emergence until harvest, growth evaluations of several morphological and productivity components of wheat plants were carried out. The obtained data were submitted to analysis of variance by F test at 5% probability and quantitative data were submitted to regression analysis in function of A.brasiliense doses whereas qualitative data in function of stocks were submitted to Tukey’s test. In protected environment, the inoculation of Azospirillum brasilense seeds provides greater growth of wheat plants, without influencing grain production. Under non-protected environment conditions, the plant growth is influenced by the inoculation of Azospirillum brasilense. The use of growth-promoting bacteria in plants increase the development of wheat plants, which represents a viable strategy, besides the environmental benefits related to the reduced utilization of nitrogen fertilizers.
Triticum aestivum is a yearly crop species belonging to the Poaceae family. It is cultivated in regions with subtropical and temperate climate, and takes up the second largest planted area in the world. Nutrient provision in the demanded amount by high productive potential cultivars, mainly nitrogen (N), is essential to obtain high productivity. The biological fixation of nitrogen is done by symbiotic microorganisms associated with plan roots. Azospirillum brasilense is one of the genera in which the symbiotic microorganisms fixate nitrogen associated with plant roots. This study aimed to evaluate the agronomical efficiency of Azospirillum brasilense inoculation on the growth and productive components of wheat cultivation. The study was divided into two experiments: the fist protected environment, and the second non-protected environment conditions, both in the School of Agriculture - Universidade Estadual Paulista “Júlio de Mesquita Filho”, Campus of Botucatu, SP, Brazil, during 2013 crop year. The experiment had completely randomized block design for the fist experiment in protected environment, and random blocks for the second experiment in non-protected environment, with 10 treatments in 3x3+1 factorial scheme. The treatments consisted of two separate (V5 and V6) and combined (V5+V6) stocks and three concentrations (65, 130 and 195 million UFC of bacteria) were applied. The control treatment had no bacterial inoculation. For the protected environment, each experimental plot consisted of plants cultivated in an asbestos recipient with the following dimensions: 0.50 m of height, 0.88 m of width and 1.05 m of length, and 0.462 m3 of soil. Seven 0.88-m rows with 0.15 m spacing and 40 seeds per meter were utilized. In the field experiment, the experimental plot consisted of ten 2.0-m rows with 0.17 m spacing and 45 seeds per meter. For both experiments, the seeding density was 266 seeds m2, aiming a density of 250 plants m2. To meet water cultivation requirements throughout the cycle, dripping irrigation was used and monitored by mercury tensiometers. After seedling emergence until harvest, growth evaluations of several morphological and productivity components of wheat plants were carried out. The obtained data were submitted to analysis of variance by F test at 5% probability and quantitative data were submitted to regression analysis in function of A.brasiliense doses whereas qualitative data in function of stocks were submitted to Tukey’s test. In protected environment, the inoculation of Azospirillum brasilense seeds provides greater growth of wheat plants, without influencing grain production. Under non-protected environment conditions, the plant growth is influenced by the inoculation of Azospirillum brasilense. The use of growth-promoting bacteria in plants increase the development of wheat plants, which represents a viable strategy, besides the environmental benefits related to the reduced utilization of nitrogen fertilizers.
Descrição
Palavras-chave
Triticum aestivum spp., Bactérias diazotróficas, Fixação biológica de nitrogênio, Sustentabilidade, Diazotrophic bacteria, Biological nitrogen fixation, Biological nitrogen fixation, Sustainability