Cadmium uptake kinetics and plants factors of shoot Cd concentration

Abstract

Background and aims Accumulation of Cd in the shoots of plants grown on Cd contaminated soils shows considerable variation. A previous preliminary experiment established that one major reason for this variation was the rate of Cd influx into the roots (mol Cd cm −2 root s −1 ). However, this experiment did not distinguish between solubilization of soil Cd on the one hand and difference in Cd uptake kinetics on the other. The main objectives of the present study were thus to characterize Cd uptake kinetics of plants continuously exposed to Cd concentrations similar to those encountered in soils. Furthermore we determined the factors responsible for differences in shoot Cd concentration such as net Cd influx, root areashoot dry weight ratio, shoot growth rate and proportion of Cd translocated to the shoot. Materials and methods Maize, sunflower, flax and spinach were grown in nutrient solution with five constant Cd concentrations varying from 0 to 1.0 μmolL −1 . Root and shoot parameters as well as Cd uptake were determined at two harvest dates and from these data Cd net influx and shoot growth rates were calculated.Results and conclusions Cadmium uptake kinetics, i.e. the net Cd influx vs. Cd solution concentration followed a straight line. Its slope is the root absorbing power, α,The α values of spinach and flax were about double that of maize and sunflower (5×10 −6 cms −1 vs. 2.5× 10 −6 cms −1 ). Spinach and flax had a 3-5 times higher shoot Cd concentration than maize and sunflower. The difference in shoot Cd concentration was partly due to the higher Cd influx but also to a higher translocation of Cd from root to shoot and also to a slower shoot growth rate.

LcBiP, a endoplasmic reticulum chaperone binding protein gene from Lycium chinense, confers cadmium tolerance in transgenic tobacco

“…In this study, a significant accumulation of Cd was observed in L. chinense plants after Cd stress treatment (Figure E). This result was in accordance with previous studies that increased concentration of GSH (Figure F) was observed with the increasing Cd concentration in various plants . It has been suggested that GSH synthesis is regulated not only at the levels of enzyme activity, but also at the level of expression of GSH1 or GSHS genes .…”

Cadmium Uptake by Ryegrass and Ryegrass–Clover Mixtures under Different Liming Rates

“…Although Cd uptake by plants is dependent on many factors including soil Cd concentrations and soil pH (Tudoreanu and Phillips, 2004), the acidifying effect of the clovers on the rhizosphere differs between species (McLay et al, 1997, Tang, 1997), and plant Cd uptake is also related to individual plant Cd uptake kinetics (Stritsis and Claassen, 2013). These species‐specific factors should be considered in future studies to better understand the plant‐specific regulators of Cd uptake.…”

Comparative Analysis of Heavy Metal and Arsenic Content in Various Herbal Dosage Forms Marketed in Russia

“…Например, содержание кадмия (мг/кг) составляет 0,15-0,72 для травы зверобоя; 0,05-0,36 для корней и корневищ валерианы, 0,25-0,5 для почек березы (Betulae gemmae), 0,25-0,31 для цветков бессмертника (Helichrysi arenarii flores). Следовательно, содержание данного контаминанта в ЛРП зависит в большей мере от места сбора соответствующего ЛРС, чем от морфологической части исходного ЛРС, что имеет подтверждение в современных исследованиях [14,29]. Наблюдаемая зависимость содержания кадмия от морфологической части растений в ранних исследованиях [28,30], по-видимому, связана с тем, что кадмий вносился в почву в легкодоступной для растений форме.…”