Brady D J, Edwards D G, Asher C J, Blamey F P C
Department of Agriculture, the University of Queensland, Brisbane, Queensland, Australia 4072.
New Phytol. 1993 Mar;123(3):531-538. doi: 10.1111/j.1469-8137.1993.tb03765.x.
Low activities of the monomeric aluminium (Al) species, Al , Al(OH) and Al(OH) in solution reduce root growth and root hair development in soybean [Glycine max (L.) Merr.]. Calcium (Ca) ameliorates to a certain extent the toxic effects of Al on root growth, but the interactive effects of Ca and Al on root hair development are not known. In the absence of added Al in solution culture, Ca concentration over the range 500-2000 μM had little effect on root growth or root hair development of soybean cv. Fitzroy. Where the sum of the activities of the monomeric Al species was 2 μM, taproot elongation and lateral root development of soybean was suppressed in solution with 500 μM Ca. The length of the root hair zone was only 10% of that in plants not exposed to Al, and scanning electron microscopy revealed a low density of root hairs. Increasing the Ca concentration to 2000 μM largely overcame these deleterious effects. The results are discussed in relation to the role of root hairs as infection sites for Bradyrhizobium, and the known effects of Al in suppressing nodulation in soybean.
溶液中单体铝（Al）物种Al³⁺、Al(OH)²⁺和Al(OH)₂⁺的低活性会抑制大豆[Glycine max (L.) Merr.]根系生长和根毛发育。钙（Ca）在一定程度上可改善铝对根系生长的毒性作用，但钙和铝对根毛发育的交互作用尚不清楚。在溶液培养中不添加铝时，500 - 2000 μM范围内的钙浓度对大豆品种Fitzroy的根系生长或根毛发育影响不大。当单体铝物种的活性总和为2 μM时，在含有500 μM钙的溶液中，大豆主根伸长和侧根发育受到抑制。根毛区长度仅为未接触铝植株的10%，扫描电子显微镜显示根毛密度较低。将钙浓度提高到2000 μM可在很大程度上克服这些有害影响。本文结合根毛作为慢生根瘤菌感染位点的作用以及铝对大豆结瘤的已知影响对结果进行了讨论。
