Effects of copper concentration on mineral nutrient uptake and copper accumulation in protein of copper-tolerant and nontolerant Lotus purshianus L.

摘要: Abstract One copper-tolerant and one copper-sensitive inbred line of Lotus purshianus L. derived from a copper mine waste site in Northern California the same species pasture next to were examined for effects excessive concentrations on mineral nutrient uptake accumulation protein fractions. Plants grown seeds period 24 days modified Hoagland solution culture supplemented with 3, 6, 10 μ M as sulfate. The basal without amendment was used control treatment. Cu found roots 100 times or more than that leaves. root tissue reached plateau under 6 leaf increased increase concentration culture. No difference pattern detected between nontolerant plants. caused reduction Ca P both tissues, no Increased greater Fe, Mn, Zn plants tolerant plants; this may be important growth conditions concentrations. Protein extracted leaves subjected Sephadex G-75 column separation. Two major peaks fractions detected. Under low (normal level) treatment, had similar Cu/protein ratios. However, higher challenged plant considerably ratio (peak II protein) amino acid composition copper-rich fraction II) demonstrated high asparate (about 25%) content. contents glutamate, cystine, glycine about 11, 2.5, 10%, respectively, rest acids range 2 6%. This is different phytochelatin metallothionein-like proteins which are very cysteine. Instead, rich resembles copper-binding spinach has acidic More studies needed characterize discover its possible role tolerance .