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

Crescimento, ac?mulo de nutrientes e fixa??o biol?gica de nitrog?nio em Flemingia macrophylla [(Willd.) Merril]. / Growth, nutrient accumulation and biological nitrogen fixation in Flemingia macrophyla [(Willd.) Merril].

Salmi, Alexandre Porto 31 July 2008 (has links)
Made available in DSpace on 2016-04-28T14:58:37Z (GMT). No. of bitstreams: 1 2008 - ALEXANDRE PORTO SALMI.pdf: 1554795 bytes, checksum: a6848d37084d24af12afa69b12020065 (MD5) Previous issue date: 2008-07-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Flemingia macrophylla is an underexploited Asian legume shrub in Brazil. International literature emphasizes its high potential as component in agroforestry systems in various regions of the tropics. The objective of this dissertation is to evaluate the potential of Flemingia macrophylla as an alternative green manure to be included in agroecological based systems. Two field experiments were conducted from December 12 2006 through December 19 2007. The first experiment was performed in Serop?dica, at sea level, and the second, in Avelar, Paty do Alferes at 500 m altitude. On both experiments twelve monthly plant samplings were performed. Variables measured included stem diameter, number of follioles, and number of branches. Besides, in the first experiment, leaf area, root volumes and biomass, number of nodules and nutrients were quantified monthly. Estimates of biological nitrogen fixation were also accomplished by natural abundance of 15N. The experimental design was a randomized complete block with 12 treatments and four replicates. A previous germination test indicated that pre-incubation with 95% sulphuric acid for 20 minutes resulted in 88% germination, whereas immersion in 90oC water, 44%. On the filed experiments, plants performed better in Serop?dica. The majority of variables were adjusted to second degree polynomial equations. Growth rates were adjusted to Gompertz model. Maximum heights were 1.8 and 1.4 m in Serop?dica and Avelar, respectively. Biomass yields reached 4.1 Mg ha-1 in Serop?dica and 2.3 Mg ha-1 in Avelar. Accumulation of N, P and K at 360 days after planting was 72.6 and 24.4 kg ha-1, respectively in Serop?dica. The highest growth rate was found between 150 and 180 days. The percentage of N derived from biological N fixation was similar at 240, 300 and 360 day after planting, averaging 76.9%, which is equivalent to 62.2 kg N ha-1 at 360 days. The results indicate that Flemingia macrophylla may provide significant amounts of biomass and nutrients, especially N, being a promising species to be included in agroecological production systems. / Flemingia macrophylla ? uma leguminosa arbustiva de origem asi?tica, pouco conhecida e utilizada no Brasil. A literatura destaca seu elevado potencial em diferentes sistemas agroflorestais em v?rias regi?es tropicais do mundo. Esta disserta??o tem como objetivo avaliar o potencial agron?mico de flemingea como alternativa de adubo verde para inclus?o em sistemas diversos de produ??o com base agroecol?gica. Para tanto, realizou-se dois experimentos em condi??es de campo, em 12/12/2006 at? 19/12/2007. O primeiro experimento foi instalado no munic?pio de Serop?dica, a 33 metros de altitude pr?ximo do n?vel do mar e o segundo, em Avelar, Munic?pio de Paty do Alferes a 500 m de altitude. Nos dois experimentos, foram feitas doze coletas mensais das plantas, onde foram determinada altura, di?metro do caule, n?mero de fol?olos e n?mero de ramifica??es. Al?m disso, no experimento I, determinou-se a ?rea foliar, volume e biomassa de ra?zes, biomassa de folhas e caule, n?mero de n?dulos e teores de nutrientes em folhas e caules. Foi ainda realizada estimativa da fixa??o biol?gica de nitrog?nio por meio da abund?ncia natural de 15N. O delineamento utilizado em ambos os experimentos foi em blocos casualizados, com 12 tratamentos (?pocas de coleta) e quatro repeti??es. O teste de germina??o indicou que o tratamento de pr?-incuba??o por vinte minutos com ?cido sulf?rico (95%), resultou em 88% de sementes germinadas, ao passo que o tratamento de imers?o em ?gua quente (90oC) resultou em 44%. Quanto aos experimentos a campo, houve melhor desempenho das plantas em Serop?dica. As alturas m?ximas foram de 1,8 e 1,4 m para Serop?dica e Avelar, respectivamente. A produ??o de biomassa aos 360 dias ap?s transplantio, chegou a valores em torno de 4,1 Mg ha-1 para Serop?dica e 2,3 Mg ha-1 para Avelar. O ac?mulo de N, P e K aos 360 DAT foi de 72,6 e 24,4 e 33 kg ha-1, respectivamente, em Serop?dica. Neste local, observou-se maior taxa de crescimento absoluto entre 150 e 180 DAT. Em rela??o ? produ??o de sementes, n?o se observou diferen?a estat?stica significativa entre os dois locais, apresentando rendimentos de 21,5 e 8,9 kg ha-1. A percentagem de N proveniente da fixa??o biol?gica foi semelhante nas tr?s ?pocas (240 DAT, 300 DAT e 360 DAT) com m?dia de 76,9 % o que equivaleu a 62,2 kg N ha-1 aos 360 DAT. Os resultados indicam que Flemingia macrophylla ? uma esp?cie que pode fornecer quantidades significativas de biomassa e nutrientes, especialmente N, sendo promissora para inclus?o em sistemas de produ??o com base agroecol?gica.

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