01743naa a2200289 a 450000100080000000500110000800800410001910000200006024501340008026000090021452009820022365000120120565000130121765000100123065000130124065000140125365000120126765000160127965000160129565000090131165000090132065000090132965300140133870000170135270000180136977300660138715583482009-05-15       1998    bl ---       0--  u    #d1 aSANZONOWICZ, C.  aCalcium alleviation of hydrogen and aluminum inhibition of soybean root extension from limed soil into acid subsurface solutions.  c1998  aAlleviation by calcium (Ca) of inhibition of soybean [Glycine max (L) Merr. cv. 'Ranson'] root elongation by hydrogen (H) aluminum (Al) was evaluated in a vertical split-root system. Roots extending from a limed and fertilized soil compartment grew for 12 days into a subsurface compartment containing nutrient solution with treatments consisting of factorial combinations of either pH (4.0, 4.6, and 5.5) and Ca (0.2,2.0,10, and 20mM), Al(7.5,15, and 30 uM) and Ca (2.0, 10, and 20mM) at pH 4.6, or Ca(2,7, and 12mM) levels and counter ions (SO and CI) at pH 4.6. and 15 uM AI. Lenght of tap roots and their laterals increased with solution Ca concentration and pH roots were greater when Ca was supplied as CaSO than CaCI, but increasing Ca concentration from 2 to 12 mM had a greater effect on alleviating AI toxicity than Ca source. In the absence of AI, relative root length (RRL) of tap and lateral roots among pH and Ca treatments was relatefd to the Ca:H molar activity  acalcium  ahydrogen  aroots  asoybeans  aAlumínio  aCálcio  aGlycine Max  aHidrogênio  aRaiz  aSoja  aSolo  aAluminium1 aSMYTH, T. J.1 aISRAEL, D. W.  tJournal of plant nutrition, New Yorkgv.21, n.4, p.785, 1998.