02973nam a2200289Ia 4500003001000000005001700010040000900027090001100036245009000047490004600137520201900183650001902202650002202221650000802243650002002251650001002271650001302281700001502294700001502309700001302324700001602337856015602353942001402509008004102523999001702564952010202581MX-MdCICY20260521091126.0  cCICY  aB-892810aNitric Oxide is Involved in Nitrate-induced Inhibition of Root Elongation in Zea mays0 vAnnals of Botany, 100(3), p.497-503, 20073 aBackground and Aims Root growth and development are closely dependent upon nitrate supply in the growth medium. To unravel the mechanism underlying dependence of root growth on nitrate, an examination was made of whether endogenous nitric oxide (NO)is involved in nitrate-dependent growth of primary roots in maize. + Methods Maize seedlings grown in varying concentrations of nitrate for 7 d were used to evaluate the effects on root elongation of a nitric oxide (NO)donor (sodium nitroprusside, SNP), a NO scavenger (methylene blue, MB), a nitric oxide synthase inhibitor (Nv-nitro-L-arginine, L-NNA), H2O2, indole-3-acetic acid (IAA)and a nitric reducatse inhibitor (tungstate). The effects of these treatments on endogenous NO levels in maize root apical cells were investigated using a NO-specific fluorescent probe, 4, 5-diaminofluorescein diacetate (DAF-2DA)in association with a confocal microscopy. + Key Results Elongation of primary roots was negatively dependent on external concentrations of nitrate, and inhibition by high external nitrate was diminished when roots were treated with SNP and IAA. MB and L-NNA inhibited root elongation of plants grown in low-nitrate solution, but they had no effect on elongation of roots grown in highnitrate solution. Tungstate inhibited root elongation grown in both low- and high-nitrate solutions. Endogenous NO levels in root apices grown in high-nitrate solution were lower than those grown in low-nitrate solution. IAA and SNP markedly enhanced endogenous NO levels in root apices grown in high nitrate, but they had no effect on endogenous NO levels in root apical cells grown in low-nitrate solution. Tungstate induced a greater increase in the endogenous NO levels in root apical cells grown in low-nitrate solution than those grown in high-nitrate solution. Conclusions Inhibition of root elongation in maize by high external nitrate is likely to result from a reduction of nitric oxide synthase-dependent endogenous NO levels in maize root apical cells.14aNITRATE SUPPLY14aNITRIC OXIDE (NO)14aIAA14aROOT ELONGATION14aMAIZE14aZEA MAYS12aZhao, D.Y.12aTian, Q.Y.12aLi, L.H.12aZhang, W.H.40uhttps://drive.google.com/file/d/1RA-RbhGs6nppi-FGxv8UHUpN0-1pLXlW/view?usp=drivesdkzPara ver el documento ingresa a Google con tu cuenta: @cicy.edu.mx  2LoccREF1250602s9999    xx |||||s2   |||| ||und|d  c19129d19129  00102Loc40708F1aCICYbCICYcREd2025-06-25l0oB-8928r2025-06-25 12:47:29w2025-06-25yREF1