Forest Genetics and Ecophysiology Research Group, School of Forest Engineering, Technical University of Madrid Madrid, Spain.
Departamento de Química Agrícola, Facultad de Ciencias, Universidad Autónoma de Madrid Madrid, Spain.
Front Plant Sci. 2014 Mar 25;5:104. doi: 10.3389/fpls.2014.00104. eCollection 2014.
The calcifuge and calcicole character of wild plants has been related to nutrient availability shortages, including iron (Fe)-deficiency. Surprisingly, just a few studies examined the relation between root Fe uptake and plant distribution in different soil types. We assessed the root Fe acquisition efficiency of two Ulmus species with calcareous (Ulmus minor) and siliceous (U. laevis) soil distribution patterns in the Iberian Peninsula. Seedlings of both elm species were grown hydroponically with different Fe concentrations during 6 weeks. Plant physiological responses to Fe-limiting conditions were evaluated as were the ferric reductase activity and proton (H(+)) extrusion capacity of the roots. Iron deprived elm seedlings of both species were stunted and suffered severe Fe-chlorosis symptoms. After Fe re-supply leaf chlorophyll concentrations rose according to species-dependent patterns. While U. minor leaves and seedlings re-greened evenly, U. laevis did so along the nerves of new growing leaves. U. minor had a higher root ferric reductase activity and H(+)-extrusion capability than U. laevis and maintained a better nutrient balance when grown under Fe-limiting conditions. The two elm species were found to have different Fe acquisition efficiencies which may be related to their natural distribution in calcareous and siliceous soils of the Iberian Peninsula.
野生植物的钙抑和嗜钙特性与养分供应短缺有关，包括缺铁（Fe）。令人惊讶的是，只有少数研究探讨了根 Fe 吸收与不同土壤类型中植物分布之间的关系。我们评估了具有钙质（Ulmus minor）和硅质（U. laevis）土壤分布模式的两个榆树物种的根 Fe 吸收效率在伊比利亚半岛。两种榆树苗在水培条件下用不同的 Fe 浓度生长 6 周。评估了植物对缺铁条件的生理反应，以及根的铁还原酶活性和质子（H+）外排能力。两种物种的缺铁榆树幼苗都受到抑制，并遭受严重的 Fe 缺素症状。Fe 再供应后，叶片叶绿素浓度根据物种依赖性模式上升。虽然 U. minor 的叶子和幼苗均匀地重新变绿，但 U. laevis 则沿着新生长叶子的神经变绿。与 U. laevis 相比，U. minor 的根铁还原酶活性和 H+外排能力更高，在 Fe 限制条件下生长时能保持更好的养分平衡。发现这两个榆树种具有不同的 Fe 吸收效率，这可能与它们在伊比利亚半岛钙质和硅质土壤中的自然分布有关。
