02999nam a2200589 a 450000100080000000500110000800800410001910000230006024501300008326000530021330000100026649000230027650000600029952015450035965000120190465000120191665000140192865000260194265000150196865000120198365000170199565000130201265000110202565000140203665000120205065000160206265000170207865000130209565000150210865000140212365000160213765000120215365000140216565000110217965000140219065000090220465000120221365300070222565300140223265300070224665300080225365300370226165300110229865300070230965300070231665300160232365300080233965300290234765300060237665300110238265300160239316214941997-06-23       1978    bl uuuu  m   00u1 u    #d1 aCARNEIRO, M. M. de  aA Comparative study of the responses of six Stylosanthes species to acid soil factors with particular reference to aluminium.  aQueensland: University of Queesland, Marcoc1978  a298p.  aTese de Doutorado.  aOrientada por: D. G.Edwards, C. S.Andrew e C. J. ASHER.  aThe present investigation was conducted to examine the comparative ability of six Stylosanthes species to tolerate acid soil infertility factors with particular reference to aluminium. Initially, a pot experiment was conducted to identify those factors limiting the growth of Stylosanthes in three acid soils from south east Queesland. All six species responded positively to lime appplication in the three soils, while responses to phosphate application varied with soils, species and lime rates. Lowest dry matter yield in the unlimed soils was associated with solution aluminium concentrations in the saturation extract ranging from 37 to 55 micrometros. Maximum growth of species occurred when the solution aluminium concentrations were reduced to the range 17 to   22 micrometros by the highest lime rates, which reduced the aluminium saturation of the effective CEC to less than 5 percent in all three soils. The growth response to lime was attribured to the alleviation of aluminium toxicity. Subsequent experiments conducted using sand culture showed that aluminium could restrict the growth of Stylosanthes species both through effects on host plant qrowth and on the development of an effective legume-Rhizobium symbiosis. However, plant qrowth was shown to be considerabily more tolerant to aluminium toxicity when supplied with adequate combined nitrogen than when dependent on symbiotic nitrogen fixation. The greater sensitivity to aluminium toxicity of plants dependent on symbiotic nitrogen fixation was shown to be due.....  acalcium  alegumes  amanganese  anutrient deficiencies  aphosphorus  asoil pH  aStylosanthes  atoxicity  aAcidez  aAlumínio  aCálcio  aCrescimento  aDeficiência  aFósforo  aLeguminosa  aManganês  aMolibdênio  aNódulo  aNutriente  aPlanta  aRhizobium  aSolo  aToxidez  aAl  aAluminium  aCa  aFBN  aFixação biológica de nitrogen  aGrowth  aMg  aMo  aMolybdenium  aNBF  aNitrogen fixing bacteria  aP  aPlants  aRoot nodule