01896nam a2200193Ia 4500003001000000005001700010040000900027245010400036490004100140520123200181650001601413650001001429650001601439650001801455700001601473700001601489856015601505008004101661MX-MdCICY20260521091205.0  cCICY10aAmino-acid influx at the soil-root interface of Zea mays L. and its implications in the rhizosphere0 vPlant and Soil, 163(1), p.1-12, 19943 aThe aim of the study was to investigate the ability of intact Zea mays. L. roots to regulate the amount of free amino-acids present in the rhizosphere. Using metabolic inhibitors it was demonstrated that the release of aminoacids from the root occurred by passive diffusion, whilst free amino-acids outside the root could be re-captured by an active transport mechanism. The influx of amino-acids into the root was shown to be relatively independent of spatial location along the root and was little affected by the presence of other organic compounds in solution. It was deduced from root concentration gradients that the main site of amino-acid exudation was at root tips. Amino-acid uptake by the root was shown to be independent of both inorganic-N concentration and the presence of other organic solutes in solution. A computer simulation model was constructed to assess the contribution of organic-N uptake (acidic, basic and neutral amino-acids)to the plant's N budget, in comparison to the inorganic solutes NO3 and NH4. Simulations of N uptake from a 0.5 mm radius rhizosphere indicated that when inorganic-N concentrations in soil were limiting (~< 0.1 pmoles cm -3 soil), the uptake of amino-N accounted for up to 9014aAMINO-ACIDS14aMAIZE14aRHIZOSPHERE14aROOT EXUDATES12aJones, D.L.12aDarrah, Rr.40uhttps://drive.google.com/file/d/1ig0Qdg4N00333T_bNYTcP6I95Eq7-_cb/view?usp=drivesdkzPara ver el documento ingresa a Google con tu cuenta: @cicy.edu.mx250602s9999    xx |||||s2   |||| ||und|d