Effects of two iron sources on iron and cadmium allocation in poplar (Populus alba) plants exposed to cadmium

Abstract

Effects of 10 microM cadmium (supplied as Cd nitrate) on the utilization and allocation of iron (Fe) were investigated in poplar (Populus alba L.) plants grown in nutrient solution with Fe(III)-EDTA or Fe(III)-citrate as the Fe source. The effects of Cd were also compared with those of Fe deprivation. The accumulation of Fe in roots was 10-fold higher in plants grown with Fe-citrate than with Fe-EDTA. Cadmium decreased leaf chlorophyll concentrations and photosynthetic rates, and these decreases were more marked in plants grown with Fe-citrate than with Fe-EDTA. In both Fe treatments, addition of Cd caused large increases in root and shoot apoplasmic and non-apoplasmic Cd contents and increases in root Fe content; however, Cd decreased shoot Fe content, especially in plants grown with Fe-citrate. New leaves of plants grown with Fe-citrate had small cellular (non-apoplasmic) Fe pools, whereas these pools were large in new leaves of plants grown with Fe-EDTA. Non-apoplasmic Cd pools in new leaves were smaller in plants grown with Fe-citrate than with Fe-EDTA, indicating that inactivation of non-apoplasmic Cd pools is facilitated more by Fe-EDTA than by Fe-citrate. In the presence of Cd, Fe-EDTA was also superior to Fe-citrate in maintaining an adequate Fe supply to poplar shoots. Differences in plant responses to Fe-EDTA and Fe-citrate may reflect differences in long-distance transport of Fe rather than in acquisition of Fe by roots.

Growth, yield and physiology of Verticillium-inoculated pepper plants treated with ATAD and composted sewage sludge

“…Plant Soil (2009) 319:291-306shown) revealed concentrations far below those inducing symptoms in plants (see Fodor et al 2005 and references therein; Larbi et al 2002), and plants did not develop heavy metals-related symptoms during the whole experiment. In line with this, in a separate experiment using ATAD as amendment, leaf concentrations of heavy metals were similar in presence or absence of the sewage sludge (Pascual et al 2008).…”

Populus deltoides females are more selective in nitrogen assimilation than males under different nitrogen forms supply

“…The extracts were centrifuged at 4,000 r min -1 under 4°C for 20 min. Up to 0.2 ml supernatants were treated with 1.2 ml of 0.1 mol L -1 potassium nitrate potassium Concentrations are in millimolar (Fodor et al 2005) Trees (2015) 29:143-159 145 phosphate buffer (pH 7.5) and 0.4 ml 2 mg ml -1 NADH. The mixture was then placed in a water bath at room temperature (25°C) for 30 min.…”

Distribution and concentration of cadmium in root tissue of Populus alba determined by scanning electron microscopy and energy-dispersive x-ray microanalysis

“…Knowledge of Cd distribution in white pop lar roots of various clones may help to un derstand some mechanisms of Cd accumula tion and tolerance in this multipurpose tree species and to select for desirable genotypes. White poplar has rapid growth, and is natur ally found on a wide range of soil types, be ing relatively tolerant to pollution (Madejón et al 2004, Fodor et al 2005. These poplars grow on riverbanks, in south and central Europe, Western Asia and North Africa; be sides, they are widely used in urban forestry.…”