Low-molecular-weight organic acids in rhizosphere soils of durum wheat and their effect on cadmium bioaccumulation
Low-molecular-weight organic acids in rhizosphere soils of durum wheat and their effect on cadmium bioaccumulation
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DOI：
10.1023/a:1004325817420
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发表时间：
1998-06-01
期刊：
影响因子：
4.9
通讯作者：
Huang, PM
中科院分区：
文献类型：
--
作者：
Cieslinski, G;Van Rees, KCJ;Huang, PM
硬粒小麦（Triticum turgidum var. durum），并推测在土壤-根界面（根际）产生的低分子量有机酸（LMWOAs）可能在这些植物对Cd的有效性和吸收中起重要作用。因此，本研究的目的是：（1）调查硬粒小麦品种Areola（低Cd积累）和凯尔（高Cd积累）在三种不同土壤中生长的根际低分子量有机酸的性质和数量：约克顿，萨瑟兰和Waitville，（2）确定这些植物中Cd积累和根际低分子量有机酸之间的关系。植物在生长室条件下在盆栽中生长两周。草酸，富马酸，琥珀酸，L-苹果酸，酒石酸，柠檬酸，乙酸，丙酸和丁酸被发现和定量的根际土壤的水提取物，乙酸和琥珀酸为主。在散装土壤中未发现水可提取的LMWOAs。3种土壤中，高Cd积累土壤（凯尔）根际土壤LMWOAs总量均显著高于低Cd积累土壤（Arcola）。同一品种在不同土壤中的根际土壤中低分子量有机酸含量差异较大，表现为Sutherland > Waitville > Yorkton。可提取的帆镉（M NH 4Cl）和镉的积累在植物中也遵循相同的土壤序列LMWOA生产。高、低镉积累品种的镉积累量与各品种根际土壤中低分子量有机酸的含量成正比。这些结果表明，不同水平的LMWOAs存在于根际土壤中发挥了重要的作用，颗粒结合到土壤溶液中的溶解和随后的植物积累的高，低镉积累品种。
Cadmium (Cd) accumulation has been found to vary between cultivars of durum wheat (Triticum turgidum var. durum), and it is hypothesized that low-molecular-weight organic acids (LMWOAs) produced at the soil-root interface (rhizosphere) may play an important role in the availability and uptake of Cd by these plants. The objective of this study, therefore, was Co (1) investigate the nature and quantity of LMWOAs present in the rhizosphere of durum wheat cultivars Areola (low Cd accumulator) and Kyle (high Cd accumulator) grown in three different soils: Yorkton, Sutherland and Waitville, and (2) determine the relationship between Cd accumulation in these plants and LMWOAs present in the rhizosphere. Plants were grown for two weeks in pot-cultures under growth chamber conditions. Oxalic, fumaric, succinic, L-malic, tartaric, citric, acetic, propionic and butyric acids were found and quantified in the water extracts of rhizosphere soil, with acetic and succinic acids being predominant. No water extractable LMWOAs were identified in the bulk soil. Total amount of LMWOAs in the rhizosphere soil of the high Cd accumulator (Kyle) was significantly higher than that for the low Cd accumulator (Arcola) in all three soils. Furthermore, large differences in amounts of LMWOAs were found in the rhizosphere soil for the same cultivars grown in different soils and followed the pattern: Sutherland > Waitville > Yorkton. Extractable sail Cd (M NH4Cl) and Cd accumulation in the plants also followed the same soil sequence as LMWOA production. Cadmium accumulation by the high and low Cd accumulating cultivars was proportional to the levels of LMWOAs found in the rhizosphere soil of each cultivar. These results suggest that the differing levels of LMWOAs present in the rhizosphere soil played an important role in the solubilization of particulate-bound Cd into soil solution and its subsequent phytoaccumulation by the high and low Cd accumulating cultivars.