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Registro Completo |
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Biblioteca(s): |
Embrapa Agrobiologia. |
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Data corrente: |
27/06/1995 |
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Data da última atualização: |
17/09/1999 |
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Autoria: |
SYLVESTER-BRADLEY, R.; OLIVEIRA, L. A. de; PODESTA FILHO, J. A. de; ST. JOHN, T. V. |
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Título: |
Nodulation of legumes, nitrogenase activity of roots and occurrence of nitrogen-fixing Azospirillum spp. in representative soils of central Amazonia. |
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Ano de publicação: |
1980 |
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Fonte/Imprenta: |
Agro-Ecosystems, Amsterdam, v. 6, p. 249-266, 1980. |
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Idioma: |
Inglês |
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Conteúdo: |
Leguminosae do not predominante in the Brazilian Amazon rain forest, although they are amoung the five best represented families. Plant roots from various soils were examined for the presence of nodules, acetylene-reducing activity and N2-fixing Azospirillum spp. Abundant nodulation was found in black earth ("terra preta dos indios") and in one case on sandy soil under campinarana vegetation along a tributary of the upper Rio Negro. Nodules were not found on plants from many other soils and sites in this area, nor in primary or secondary forest on clayey latosol near Manaus. In sandy latosol some nodules occurred in secondary forest and fewer in primary forest. Legumes in disturbed clayey or sandy latosol showed more frequent nodulation. Primary forest on alluvial ("varzea") soil, and in Bahia coastal rain forest on sandy latosol and Erythrina glauca used for shading cacao plantations were abundantly nodulated. Acetylene reduction assays showed no, or very little, nitrogenase activity of roots from primary or secondary forest on clayey latosol near Manaus. Nodulated roots from secondary forest on sandy latosol showed acetylene-reducing activity. High rates of acetylene reduction were observed in nodulated roots of primary forest on alluvial "varzea" soil. Root samples showed ethylene absorption in controls without acetylene which might interfere with the results of acetylene reduction tests. The incidence of Azospirillum was also higher in black earth than the other soils examined, and in soils with higher pH. The hypothesis that Azospirillum is associated with Trema micrantha roots was refuted. Roots and soils collected under cultivated grasses showed a higher incidence of Azospirillum when fertilized with phosphorus and lime. Results indicate that nitrogen fixation did occur in association with roots in some soils, but not with roots of primary or secondary forest on clayey latosol in the vicinity of Manaus, which is the most common soil in Central Amazonia. The possible reasons for this are discussed. MenosLeguminosae do not predominante in the Brazilian Amazon rain forest, although they are amoung the five best represented families. Plant roots from various soils were examined for the presence of nodules, acetylene-reducing activity and N2-fixing Azospirillum spp. Abundant nodulation was found in black earth ("terra preta dos indios") and in one case on sandy soil under campinarana vegetation along a tributary of the upper Rio Negro. Nodules were not found on plants from many other soils and sites in this area, nor in primary or secondary forest on clayey latosol near Manaus. In sandy latosol some nodules occurred in secondary forest and fewer in primary forest. Legumes in disturbed clayey or sandy latosol showed more frequent nodulation. Primary forest on alluvial ("varzea") soil, and in Bahia coastal rain forest on sandy latosol and Erythrina glauca used for shading cacao plantations were abundantly nodulated. Acetylene reduction assays showed no, or very little, nitrogenase activity of roots from primary or secondary forest on clayey latosol near Manaus. Nodulated roots from secondary forest on sandy latosol showed acetylene-reducing activity. High rates of acetylene reduction were observed in nodulated roots of primary forest on alluvial "varzea" soil. Root samples showed ethylene absorption in controls without acetylene which might interfere with the results of acetylene reduction tests. The incidence of Azospirillum was also higher in black earth than the other soils ex... Mostrar Tudo |
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Palavras-Chave: |
BNF; Brasil; FBN; Fixacao biologica de nitrogenio; Nitrogen fixing bacteria; Reduction; Root nodulation. |
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Thesagro: |
Acetileno; Leguminosa; Leguminosae; Nitrogenase; Nodulação; Raiz; Redução; Solo. |
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Thesaurus Nal: |
acetylene; Amazonia; Brazil; roots; soil. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 03110naa a2200397 a 4500
001 1621103
005 1999-09-17
008 1980 bl --- 0-- u #d
100 1 $aSYLVESTER-BRADLEY, R.
245 $aNodulation of legumes, nitrogenase activity of roots and occurrence of nitrogen-fixing Azospirillum spp. in representative soils of central Amazonia.
260 $c1980
520 $aLeguminosae do not predominante in the Brazilian Amazon rain forest, although they are amoung the five best represented families. Plant roots from various soils were examined for the presence of nodules, acetylene-reducing activity and N2-fixing Azospirillum spp. Abundant nodulation was found in black earth ("terra preta dos indios") and in one case on sandy soil under campinarana vegetation along a tributary of the upper Rio Negro. Nodules were not found on plants from many other soils and sites in this area, nor in primary or secondary forest on clayey latosol near Manaus. In sandy latosol some nodules occurred in secondary forest and fewer in primary forest. Legumes in disturbed clayey or sandy latosol showed more frequent nodulation. Primary forest on alluvial ("varzea") soil, and in Bahia coastal rain forest on sandy latosol and Erythrina glauca used for shading cacao plantations were abundantly nodulated. Acetylene reduction assays showed no, or very little, nitrogenase activity of roots from primary or secondary forest on clayey latosol near Manaus. Nodulated roots from secondary forest on sandy latosol showed acetylene-reducing activity. High rates of acetylene reduction were observed in nodulated roots of primary forest on alluvial "varzea" soil. Root samples showed ethylene absorption in controls without acetylene which might interfere with the results of acetylene reduction tests. The incidence of Azospirillum was also higher in black earth than the other soils examined, and in soils with higher pH. The hypothesis that Azospirillum is associated with Trema micrantha roots was refuted. Roots and soils collected under cultivated grasses showed a higher incidence of Azospirillum when fertilized with phosphorus and lime. Results indicate that nitrogen fixation did occur in association with roots in some soils, but not with roots of primary or secondary forest on clayey latosol in the vicinity of Manaus, which is the most common soil in Central Amazonia. The possible reasons for this are discussed.
650 $aacetylene
650 $aAmazonia
650 $aBrazil
650 $aroots
650 $asoil
650 $aAcetileno
650 $aLeguminosa
650 $aLeguminosae
650 $aNitrogenase
650 $aNodulação
650 $aRaiz
650 $aRedução
650 $aSolo
653 $aBNF
653 $aBrasil
653 $aFBN
653 $aFixacao biologica de nitrogenio
653 $aNitrogen fixing bacteria
653 $aReduction
653 $aRoot nodulation
700 1 $aOLIVEIRA, L. A. de
700 1 $aPODESTA FILHO, J. A. de
700 1 $aST. JOHN, T. V.
773 $tAgro-Ecosystems, Amsterdam$gv. 6, p. 249-266, 1980.
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Registro original: |
Embrapa Agrobiologia (CNPAB) |
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