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Registro Completo |
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Biblioteca(s): |
Embrapa Agrobiologia; Embrapa Pantanal. |
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Data corrente: |
27/06/1995 |
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Data da última atualização: |
09/09/1996 |
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Autoria: |
LaRUE, T. A.; PATTERSON, T. G. |
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Afiliação: |
Boyce Thompson Institute for Plant Research, Ithaca, New York. |
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Título: |
How much nitrogen do legumes fix? |
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Ano de publicação: |
1981 |
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Fonte/Imprenta: |
Advances Agronomy, v.34, p.15-38, 1981. |
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Idioma: |
Inglês
Português |
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Conteúdo: |
There is not a single crop for which we have valid estimates of the N fixed in agriculture. There are good estimates for soybean grown in representative locations in experimental plots. However, extrapolation from this data to fixation in agriculture is speculative. For other pulses the few documented reports do not permit estimation of fixation on farms. The data on forage legumes are sparse and mostly derived from studies of pure stands. Estimates from more locations are required. In practice the forages are often planted with a grass, or over time become admixed by grasses. There is an almost complete lack of data on fixation by mixed stands, or on the amounts of fixation when forages are harvested or browsed. It is regrettable that fixation by legumes, which are important to the developing world, is not better documented. Dry beans are the most important legume crop for human consumption in latin America. Cowpeas are a staple in much of Africa and Asia, and chick-pea is important in semiarid regions. For none of these are data available. There is no good evidence that any legume crop satisfie all its N requirements by fixation. Soybean fixation has been estimated in several areas of the United States and from consideration of all the data we must conclude that this crop depletes soil N. there are no substantiated reports that 100% N of any plant derives from symbiosis. The highest estimates (~80%) are typical of low fertility soil or soils artificially made N-poor by admixture or carbon amendment. MenosThere is not a single crop for which we have valid estimates of the N fixed in agriculture. There are good estimates for soybean grown in representative locations in experimental plots. However, extrapolation from this data to fixation in agriculture is speculative. For other pulses the few documented reports do not permit estimation of fixation on farms. The data on forage legumes are sparse and mostly derived from studies of pure stands. Estimates from more locations are required. In practice the forages are often planted with a grass, or over time become admixed by grasses. There is an almost complete lack of data on fixation by mixed stands, or on the amounts of fixation when forages are harvested or browsed. It is regrettable that fixation by legumes, which are important to the developing world, is not better documented. Dry beans are the most important legume crop for human consumption in latin America. Cowpeas are a staple in much of Africa and Asia, and chick-pea is important in semiarid regions. For none of these are data available. There is no good evidence that any legume crop satisfie all its N requirements by fixation. Soybean fixation has been estimated in several areas of the United States and from consideration of all the data we must conclude that this crop depletes soil N. there are no substantiated reports that 100% N of any plant derives from symbiosis. The highest estimates (~80%) are typical of low fertility soil or soils artificially made N-poor by adm... Mostrar Tudo |
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Palavras-Chave: |
15N; FBN; MAXIMO FBN A PRODUCAO; REVISAO. |
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Thesagro: |
Diluição Isotópica; Economia; Fixação de Nitrogênio; Legume; Leguminosa; Método. |
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Thesaurus Nal: |
nitrogen fixation. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 02168naa a2200265 a 4500
001 1789664
005 1996-09-09
008 1981 bl --- 0-- u #d
100 1 $aLaRUE, T. A.
245 $aHow much nitrogen do legumes fix?
260 $c1981
520 $aThere is not a single crop for which we have valid estimates of the N fixed in agriculture. There are good estimates for soybean grown in representative locations in experimental plots. However, extrapolation from this data to fixation in agriculture is speculative. For other pulses the few documented reports do not permit estimation of fixation on farms. The data on forage legumes are sparse and mostly derived from studies of pure stands. Estimates from more locations are required. In practice the forages are often planted with a grass, or over time become admixed by grasses. There is an almost complete lack of data on fixation by mixed stands, or on the amounts of fixation when forages are harvested or browsed. It is regrettable that fixation by legumes, which are important to the developing world, is not better documented. Dry beans are the most important legume crop for human consumption in latin America. Cowpeas are a staple in much of Africa and Asia, and chick-pea is important in semiarid regions. For none of these are data available. There is no good evidence that any legume crop satisfie all its N requirements by fixation. Soybean fixation has been estimated in several areas of the United States and from consideration of all the data we must conclude that this crop depletes soil N. there are no substantiated reports that 100% N of any plant derives from symbiosis. The highest estimates (~80%) are typical of low fertility soil or soils artificially made N-poor by admixture or carbon amendment.
650 $anitrogen fixation
650 $aDiluição Isotópica
650 $aEconomia
650 $aFixação de Nitrogênio
650 $aLegume
650 $aLeguminosa
650 $aMétodo
653 $a15N
653 $aFBN
653 $aMAXIMO FBN A PRODUCAO
653 $aREVISAO
700 1 $aPATTERSON, T. G.
773 $tAdvances Agronomy$gv.34, p.15-38, 1981.
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Registro original: |
Embrapa Pantanal (CPAP) |
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