Registro Completo |
Biblioteca(s): |
Embrapa Agropecuária Oeste; Embrapa Cerrados. |
Data corrente: |
15/08/1996 |
Data da última atualização: |
10/09/1997 |
Autoria: |
ANDRADE, L. R. M. de. |
Título: |
Physiological studies on varietal differences in aluminum tolerance in wheat. |
Ano de publicação: |
1996 |
Fonte/Imprenta: |
[Fukuoka, Japan]: [Kyushu University], 1996. |
Páginas: |
131p. |
Idioma: |
Inglês |
Notas: |
[Tese Doutorado]. |
Conteúdo: |
Differential Al-tolerance in plants, particularly wheat varieties has been extensively studied, but the mechanisms of Al toxicity and tolerance are still not well understood. The objective of this work was to investigate the mechanisms of Al-tolerance in wheat varieties screened for Al-tolerance by the hematoxylin staining method, with emphasis on a) the formation of a plant-induced pH barrier in the rhizosphere and b) the exudation of chelator ligands. A second objective was to clarify the effect of Al on the metabolism of malate in roots leading to its excretion using 14C tracer technique. Selected six wheat varieties differing in Al tolerance were used to determine the combined effects of Al and N sources on solution pH changes and nutrient absorption by plants. NO3- uptake was severely inhibited by the presence of Al while NH4+ uptake was little affected. Al decreased the amounts of Ca, Mg, and K accumulated in whole plants independent of N sources. The changes in the solution pH were a consequence of general effect of Al on nutrient uptake, msinly N (NH4+ and N03-), and they were not directly correlated with the scoring of Al-tolerance. Plants grown in N03--N accumulated more Al in the roots and it might be related to solution pH-changes. Tolerant varieties accumulated less Al. It was concluded the differential Al-tolerance among those varieties could not be explained solely by the ability of plants to maintain a high solution pH in mixed N solutions. The root apex (root cap, meristem, and root elongation ... MenosDifferential Al-tolerance in plants, particularly wheat varieties has been extensively studied, but the mechanisms of Al toxicity and tolerance are still not well understood. The objective of this work was to investigate the mechanisms of Al-tolerance in wheat varieties screened for Al-tolerance by the hematoxylin staining method, with emphasis on a) the formation of a plant-induced pH barrier in the rhizosphere and b) the exudation of chelator ligands. A second objective was to clarify the effect of Al on the metabolism of malate in roots leading to its excretion using 14C tracer technique. Selected six wheat varieties differing in Al tolerance were used to determine the combined effects of Al and N sources on solution pH changes and nutrient absorption by plants. NO3- uptake was severely inhibited by the presence of Al while NH4+ uptake was little affected. Al decreased the amounts of Ca, Mg, and K accumulated in whole plants independent of N sources. The changes in the solution pH were a consequence of general effect of Al on nutrient uptake, msinly N (NH4+ and N03-), and they were not directly correlated with the scoring of Al-tolerance. Plants grown in N03--N accumulated more Al in the roots and it might be related to solution pH-changes. Tolerant varieties accumulated less Al. It was concluded the differential Al-tolerance among those varieties could not be explained solely by the ability of plants to maintain a high solution pH in mixed N solutions. The root apex (roo... Mostrar Tudo |
Palavras-Chave: |
Aluminium; Diferenca varietal; Difference; Malato; Mecanismo; Mechanism; Organic acids; Plant soil relations; Soil deficiencies; Soil toxity; Tolerance; Tolerancia; Toxicidade. |
Thesagro: |
Ácido Orgânico; Alumínio; Fisiologia Vegetal; Raiz; Relação Solo-Planta; Rizosfera; Toxidez; Trigo; Triticum Aestivum; Variedade. |
Thesaurus Nal: |
aluminum; malates; plant physiology; rhizosphere; roots; toxicity; varieties; wheat. |
Categoria do assunto: |
-- |
Marc: |
LEADER 02787nam a2200505 a 4500 001 1557073 005 1997-09-10 008 1996 bl uuuu m 00u1 u #d 100 1 $aANDRADE, L. R. M. de 245 $aPhysiological studies on varietal differences in aluminum tolerance in wheat. 260 $a[Fukuoka, Japan]: [Kyushu University]$c1996 300 $a131p. 500 $a[Tese Doutorado]. 520 $aDifferential Al-tolerance in plants, particularly wheat varieties has been extensively studied, but the mechanisms of Al toxicity and tolerance are still not well understood. The objective of this work was to investigate the mechanisms of Al-tolerance in wheat varieties screened for Al-tolerance by the hematoxylin staining method, with emphasis on a) the formation of a plant-induced pH barrier in the rhizosphere and b) the exudation of chelator ligands. A second objective was to clarify the effect of Al on the metabolism of malate in roots leading to its excretion using 14C tracer technique. Selected six wheat varieties differing in Al tolerance were used to determine the combined effects of Al and N sources on solution pH changes and nutrient absorption by plants. NO3- uptake was severely inhibited by the presence of Al while NH4+ uptake was little affected. Al decreased the amounts of Ca, Mg, and K accumulated in whole plants independent of N sources. The changes in the solution pH were a consequence of general effect of Al on nutrient uptake, msinly N (NH4+ and N03-), and they were not directly correlated with the scoring of Al-tolerance. Plants grown in N03--N accumulated more Al in the roots and it might be related to solution pH-changes. Tolerant varieties accumulated less Al. It was concluded the differential Al-tolerance among those varieties could not be explained solely by the ability of plants to maintain a high solution pH in mixed N solutions. The root apex (root cap, meristem, and root elongation ... 650 $aaluminum 650 $amalates 650 $aplant physiology 650 $arhizosphere 650 $aroots 650 $atoxicity 650 $avarieties 650 $awheat 650 $aÁcido Orgânico 650 $aAlumínio 650 $aFisiologia Vegetal 650 $aRaiz 650 $aRelação Solo-Planta 650 $aRizosfera 650 $aToxidez 650 $aTrigo 650 $aTriticum Aestivum 650 $aVariedade 653 $aAluminium 653 $aDiferenca varietal 653 $aDifference 653 $aMalato 653 $aMecanismo 653 $aMechanism 653 $aOrganic acids 653 $aPlant soil relations 653 $aSoil deficiencies 653 $aSoil toxity 653 $aTolerance 653 $aTolerancia 653 $aToxicidade
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Registro original: |
Embrapa Cerrados (CPAC) |
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