Jauert P, Schumacher T E, Boe A, Reese R N
Dep. of Biology and Microbiology, Plant Science Dep., South Dakota State Univ., Brookings 57007, USA.
J Environ Qual. 2002 Mar-Apr;31(2):627-33.
Strawberry clover (Trifolium fragiferum L.) is a hardy legume found in indigenous or introduced populations throughout the world. Tolerance to saline and alkaline soils, flooding, and heavy metals make it a good prospect for reclamation projects. The research, described here, was conducted to: (i) characterize the morphological variation in plants from available seed sources, (ii) evaluate cadmium uptake and tolerances over a wide range of morphological variants, and (iii) elucidate the variability in the effects of roots on rhizosphere pH and the relationship to cadmium uptake. Seeds from selected accessions were planted in the greenhouse for comparison of morphological variation. The accessions examined had a mean height of 10.7+/-7 cm. Accessions 254916 and 237925 are tall with high rhizosphere pH values and might be useful in phytoremediation. Strawberry clover accessions were also grown hydroponically to examine differences in cadmium uptake. The ability of strawberry clover roots to change rhizosphere pH and take up cadmium was examined using culture tubes containing nutrient agar, a moderate level of cadmium, and a pH indicator dye. The results provided evidence for a negative correlation between rhizosphere pH and cadmium uptake.
草莓三叶草（Trifolium fragiferum L.）是一种适应性强的豆科植物，在世界各地的原生或引入种群中均有发现。它对盐碱土壤、洪水和重金属具有耐受性，这使其成为开垦项目的理想选择。本文所述的研究旨在：（i）描述现有种子来源的植物形态变异特征；（ii）评估广泛形态变异体对镉的吸收和耐受性；（iii）阐明根系对根际pH值的影响差异以及与镉吸收的关系。从选定的种质中选取种子在温室中种植，以比较形态变异。所检测的种质平均高度为10.7±7厘米。种质254916和237925较高，根际pH值也较高，可能在植物修复中有用。还通过水培法种植草莓三叶草种质，以研究镉吸收的差异。使用含有营养琼脂、中等水平镉和pH指示染料的试管，研究草莓三叶草根系改变根际pH值和吸收镉的能力。结果为根际pH值与镉吸收之间的负相关提供了证据。
