135(1):43570j (2)uptake of glycine by field grown wheat.(3) Nasholm, Trogny ; Huss-Danell, Kerstin : Hogberg, Peter(4)(Umea Plant Science Center, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Science S-901 83 Umea, Swed.) (5),New phytol (6),.2001,150 (1), (7) 69-63(Eng), (8) Blackwell Science Ltd. Uptake of glycine, a simple org. nitrogen (N) source, directly from the soil is shown here in conventionally cropped wheat (Triticum aestivum) field. Wheat plants were harvested after tracer injections into the soil of two forms of dual-labeled amino acid; [13C],[15N] glycine and 2-[13C],[15N] glycine, uptake of intact amino acid was analyzed by stable isotope-,and gas chromatog,- mass spectrometry. Significant increases in 13C were found in root exts. For all glycine-treated plants. Kegression anal.of excess 13C vs excess 15N for the two glycine forms showed that at least 20%of absorbed glycine-N was derived form uptake of intact gylcine. Gas chromatog.-mass spectrometry was used to verify the presence of intact dual-labeled glycine in wheat roots. Results also indicated that glycine decarboxylase had a minor role in metab.of absorbed glycine in wheat roots. Microbial metab in the soil did, however, result in rapid decarbonxylation of added glycine, Field-grown wheat takes up glycine directly from the soil; the dependence of agricultural plants on nitrate and ammonium as the only forms of available N is therefore questionable(9)