不同pH下局部供应硝酸盐和铵对玉米侧根生长的影响

Effects of Localized Supplement of Nitration and Ammonium on Lateral Root Growth of Maize Under Different pH Conditions

采用水培分根培养体系,比较了不同pH下局部供应不同形态氮素对玉米侧根生长的影响。结果表明,局部硝酸盐可以刺激侧根伸长,但不影响侧根密度,pH值5或pH值7对刺激效果没有显著影响。在两个pH值下,局部供应相同浓度的铵均未显著促进侧根伸长。说明铵不能显著刺激侧根的伸长并不是由于根际pH的变化。

In the present study, the effects of localized supplement of nitration and ammonium on lateral root growth in maize between two pH（5 and 7） were compared in a hydroponic split-root system. It was shown that localized nitration stimulated significantly lateral root elongation without influencing on lateral root initiation and axial root elongation. Adjust of pH did not affect the nitrate effect. Local ammonium treatment did not affect all the root parameter in four days at either pH 5 or pH 7. It is suggested that nitrate itself could stimulate lateral root elongation. The disability of ammonium in enhancing lateral root elongation is not due to the rhizosphere pH effect.