Hirano Yasuhiro, Walthert Lorenz, Brunner Ivano
Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), CH-8903, Birmensdorf, Switzerland.
Tree Physiol. 2006 Apr;26(4):431-40. doi: 10.1093/treephys/26.4.431.
We determined if callose formation in 1-cm-long root apices of European chestnut (Castanea sativa Mill.) seedlings is affected by naturally occurring high concentrations of aluminum (Al) under laboratory conditions and by low base saturation (BS) of soils under forest field conditions. Under controlled conditions in the laboratory, seedlings were treated with simulated soil solutions in the presence or absence (control) of Al. One day after exposing seedlings to a simulated soil solution containing 168 microM Al, callose formation in the root apices had increased significantly. After 7 days, callose concentration in root apices was significantly correlated with the concentration of free Al3+ ions recovered in the simulated soil solution and with the concentration of Al in fine roots. At four field sites in southern Switzerland, seedlings were grown for five months in either A-horizon soil with a BS above 17% or in a B-horizon soil with a BS below 5%. Callose concentrations were significantly higher in root apices in the B horizon than in the A horizon. Callose concentrations in root apices were negatively correlated with Ca/Al molar ratio in fine roots. We conclude that callose in the root apices of European chestnut could be a useful physiological parameter for assessing Al toxicity under both laboratory and field conditions.
我们研究了在实验室条件下，欧洲栗（Castanea sativa Mill.）幼苗1厘米长根尖中胼胝质的形成是否受自然存在的高浓度铝（Al）影响，以及在森林田间条件下是否受土壤低碱饱和度（BS）的影响。在实验室可控条件下，幼苗在有或无（对照）铝的情况下用模拟土壤溶液处理。将幼苗暴露于含168 microM铝的模拟土壤溶液一天后，根尖中胼胝质的形成显著增加。7天后，根尖中胼胝质浓度与模拟土壤溶液中回收的游离Al3+离子浓度以及细根中铝的浓度显著相关。在瑞士南部的四个田间地点，幼苗在碱饱和度高于17%的A层土壤或碱饱和度低于5%的B层土壤中生长五个月。B层根尖中的胼胝质浓度显著高于A层。根尖中的胼胝质浓度与细根中钙/铝摩尔比呈负相关。我们得出结论，欧洲栗根尖中的胼胝质可能是在实验室和田间条件下评估铝毒性的一个有用的生理参数。
