植物高铁载体在小麦适应缺铁石灰性土壤条件中的作用

植物缺铁现象是生长在 pH 值和 CaCO_3含量较高的石灰性土壤上的一种常见的营养障碍。本文探讨了介质 pH 值和 Ca~(2+)或 CaCO_3对植物高铁载体在小麦适应缺铁石灰性土壤条件中的作用,并讨论了这一适应性的生态学意义。试验结果表明,介质 pH 值(4～8)和 Ca~(2+)浓度(50～2500μmol)对植物高铁载体分泌率和高铁载体活化铁的能力无显著的影响;而当介质 pH 值从5.0上升到7.5时,植物高铁载体螯合态铁的吸收率下降了37%.加 CaCO_3与不加 CaCO_3的结果相似。这一结果说明了植物高铁载体在小麦适应缺铁石灰性土壤条件方面的作用受 pH 值和 CaCO_3含量影响较小,解释了为什么小麦是石灰性土壤上忍耐缺铁能力较强的作物种类。

The Role of Phytosiderophore in Wheat for the Adaptation to Iron Deficient Calcareous Soil

Iron deficiency in plants is one of the common physiological disorder on calcareous soils with high pH value and CaCO_3content.In this paper the effect of the pH value and Ca~(2+)or CaCO_3in the role of phytosiderophore in wheat for the adaptation to iron deficiency calcareous soil condition was studied,and the ecological significance of this mechanism was also discussed.The results shown clearly that no significant effect of medium pH(from 4 to 8)and Ca~(2+)concentration on the release of phytosiderophore ...