水 、氮供应对玉米伤流及其养分含量的影响

以玉米为供试作物, 在遮雨棚内进行了微区田间试验, 研究了不同水、氮供应玉米的伤流量, 伤流液中的硝态 氮、铵态氮、游离氨基酸及磷、钾含量, 以及对植株氮、磷、钾等养分含量和吸收量的影响。 结果表明, 供水明显增加 伤流量和伤流液中硝态氮、铵态氮、游离氨基酸及磷、钾含量。 水分充足或水分胁迫较轻时, 伤流量及其养分含量 随施氮增加而增加;水分胁迫严重时, 则减少。 在不同水、氮供应条件下, 植株氮、磷、钾养分含量及吸收量具有相 同的变化趋势。

Effects of water and N supply on maize bleeding sap and its nutrient contents

A micro-plot field experiment was conducted under a rain-shelter condition to study the effects of water and (nitrogen) supply on bleeding sap and contents of ammonium N, nitrate N, free amino acid, P and K in the sap, and the (nutrients) absorbed by plant of maize. Four factors, soil surface treatment, irrigation, N rate and root growing space, were involved in this experiment. Determinations were carried out at an interval of certain time. Results show that under water-stress condition, water supply remarkably increased the bleed and content of nutrients in the sap of maize. The effects of N supply being depended on water supply by either irrigation or soil moisture retention. With better water supply, bleeding sap and nutrients contents were increased by N addition whereas under serious water stress condition, application of N reduced the bleeding sap and nutrients content in it. N, P and K absorbed by maize had almost the same trend as the bleeding sap.