马尾松苗期体内铝离子存在方式、形态和分布

本文用溶液培养方法研究铝在马尾松幼苗体内的存在方式、形态及其分布。结果表明,①松苗吸收的铝主要积累于根部,只有较少量的铝转移至地上部分;②针叶内铝离子主要以束缚态的方式存在,根内束缚态与自由态的存在比例大致相当;③铝离子在表面自由空间大部分以三价铝离子的形态存在,其中针叶内约占63～85％,根内占41—67％;④铝离子在根组织内的含量以外皮层为最高,中柱最低,呈现为从内向外增多的分布状态.

Existing Pattern, Ionic Forms and Distribution of Aluminum in Masson Pine Seedlings

Using a hydroponic system, existing pattern, ionic forms and distribution of aluminum in masson pine seedlings were studied. Results show that: (1) Most of the aluminun absorbed by the pine seedlings accumulated in the roots and only a little of the aluminun was translocated to the shoots; (2) Majority of the aluminun in the shoots were bound, but there was only little difference in the amount of free and bound aluminum in the roots; (3) The dominant ionic form of aluminum in surface free space was AL3+ which accounted for about 63-85% of the total in the shoots and 41-67% in the roots; (4) In the roots, most of the aluminum existed in the epidermis of plant tissue and a little was found in the stele, showing an increasing tendency from the inside to the outside of plant tissues.