Figure 3.

¹³C NMR spectra of excised maize root tips in different nutritive media: regions used for quantification of sugars and amino acids. Excised maize root tips were first perifused with a medium containing 200 mm Glc during 4 h (Control, top). Then, 100 mm 3-OMG was substituted for Glc for 48 h (middle). Finally, root tips were perifused with 200 mm Glc (bottom). Ref, ¹³CH₂ resonance of ethanol contained in a capillary. Spectra were acquired at 100.61 MHz with a free induction decay (FID) resolution of 1.4 Hz, a 45° radiofrequency (RF) pulse (45 μs), and 3,000 transients repeated every 1 s.