01151naa a2200157 a 450000100080000000500110000800800410001910000190006024500830007926000090016252007010017165300230087265300180089570000220091377300580093516470821995-09-14       1980    bl ---       0--  u    #d1 aROBERTS, H. M.  aDetermination of ammonium, amides, and soluble carboxylates in plants tissues.  c1980  aMethods for extraction and determination of ammonium, amides and soluble carboxylates in plant tissues are compared and discussed. The procedure recommended involves extraction of finely ground plant tissues with 0.2 M formic acid, determination of ammonium and amides in the extract by overnight alkaline hydrolysis and distillation in Conway microdiffusion dishes, measurement of extracted ammonium using Carlson's rapid diffusion-conductivity instrument, and estimation of soluble organic acids by titration after separation and purification with ion exhange resins. The method described is reasonably rapid. The final solution of organic acids is suitable for direct chromatographic analysis.  aExtraction methods  aOrganic acids1 aREISENAUER, H. M.  tJournal of Plant Nutritiongv.2, n4, p.395-405, 1980.