“…Screening for rhizobial resistance to high A13+ or Mn2+ concentrations among cowpea bradyrhizobia (Keyser and Munns, 1979a,b;Ayanaba et al, 1983), lespedeza bradyrhizobia (Cline and Senwo, 1994), B. japonicum (Ayanaba et al, 1983), R. loti (Cooper, 1982;Wood and Cooper, 1985), R. leguminosarurn bv. trifolii (Thornton and Davey, 1983;Wood and Cooper, 1984;Richardson and Simpson, 1989), and bean rhizobia (Graham et al, 1982;Lowendorf and Alexander, 1983a;Karanja and Wood, 1988a;Vargas and Graham, 1988;Wolff et al, 1991) has shown that a tremendous difference exists in aluminum and manganese tolerance within and between species and that tolerance to acidity does not necessarily imply tolerance to these elements.…”