Quintero José Manuel, Fournier José María, Benlloch Manuel, Rodríguez-Navarro Alonso
Departamento de Ciencias Agroforestales, Escuela U. Ingeniería Técnica Agrícola, Universidad de Sevilla, Ctra. Utrera, Km. 1, E-41013 Sevilla, Spain.
J Plant Physiol. 2008 Aug 25;165(12):1248-54. doi: 10.1016/j.jplph.2007.08.011. Epub 2007 Dec 31.
Twenty-day-old sunflower plants (Helianthus annuus L. cv Sun-Gro 380) grown hydroponically under controlled conditions were used to study the effect of transpiration on Na(+) compartmentalization in roots. The plants were exposed to low Na(+) concentrations (25 mM NaCl) and different environmental humidity conditions over a short time period (8.5 h). Under these conditions, Na(+) was accumulated primarily in the root, but only the Na(+) accumulated in the root symplast was dependent on transpiration, while the Na(+) accumulated in both the shoot and the root apoplast exhibited a low transpiration dependence. Moreover, Na(+) content in the root apoplast was reached quickly (0.25 h) and increased little with time. These results suggest that, in sunflower plants under moderate salinity conditions, Na(+) uptake in the root symplast is mediated by a transport system whose activity is enhanced by transpiration.
在可控条件下进行水培的20日龄向日葵植株（向日葵品种Sun - Gro 380）被用于研究蒸腾作用对根中Na⁺区室化的影响。这些植株在短时间内（8.5小时）暴露于低Na⁺浓度（25 mM NaCl）和不同的环境湿度条件下。在这些条件下，Na⁺主要在根中积累，但只有在根共质体中积累的Na⁺依赖于蒸腾作用，而在地上部和根质外体中积累的Na⁺对蒸腾作用的依赖性较低。此外，根质外体中的Na⁺含量迅速达到（0.25小时）且随时间增加很少。这些结果表明，在中等盐度条件下的向日葵植株中，根共质体中的Na⁺吸收是由一个运输系统介导的，其活性因蒸腾作用而增强。
