氮胁迫对玉米单根径、轴向水力导度的影响

Effects of nitrogen stress on root radial and axial hydraulic conductivity of corn

氮亏缺影响地上部生长的生理机制之一可能与其对根水力导度的影响有关。为此 ,本文利用蒸腾计法和解剖学方法分别研究了氮亏缺对玉米单根径、轴向水力导度的影响。结果表明 ,氮亏缺条件下 ,玉米单根的径向和轴向导度明显下降 ,其径向导度对水孔蛋白抑制剂HgCl2 不敏感。不同氮处理轴向导度差别的主要原因在于成熟的后生木质部导管数目和直径的减少。

One of important physiological mechanism of nitrogen deficiency inhibiting the shoot growth may be related with its impacts on root hydraulic conductivity Hence,effects of nitrogen deficiency on root radial and axial hydraulic conductivity of corn were studied with potometer and anatomical method respectively in this study The results indicated that nitrogen deficiency decreased root radial and axial hydraulic conductivity of corn Root radial hydraulic conductivity of nitrogen deficiency treatment was insensitive to aquaporin inhibitor HgCl 2 The main reasons of the decrease of axial hydraulic conductivity under nitrogen deficiency were the decreased number of mature metaxylems and their smaller diameter