
TY  - JOUR
A1  - Balestrasse, Karina B. 
A1  - Benavides, María Patricia 
A1  - Gallego, Susana M. 
A1  - Tomaro, María L. 
T1  - Effect of cadmium stress on nitrogen metabolism in nodules and roots of soybean plants
JF  - Functional Plant Biology
JO  - Functional Plant Biol.
Y1  - 2003
VL  - 30
IS  - 1
SP  - 57
EP  - 64
KW  - ammonium, cadmium, glutamate, Glycine max, nitrogen metabolism.
UR  - https://doi.org/10.1071/FP02074 
N2  - The nitrogen metabolism of soybean (Glycine max L.) nodules and roots was studied in plants subjected to two different concentrations (50 and 200 &#956;M) of CdCl2. Nitrogenase activity was decreased in nodules treated with 200 &#956;M Cd2+. In 50 &#956;M Cd2+-treated plants, NH4+ content showed similar values to controls in nodules, but increased by 55% in roots. However, after treatment with 200 &#956;M Cd2+, NH4+ levels increased in both tissues. Glutamate (Glu) and protein contents remained unaltered in nodules treated with 50 &#956;M Cd2+, while at the higher Cd2+ concentration both were decreased. Nevertheless, polyamine content was increased at the two Cd2+ concentrations. In roots, Glu, polyamine and protein levels were significantly diminished at 50 and 200 &#956;M CdCl2. For nitrogen-assimilation enzymes, glutamate dehydrogenase activity was moderately increased in nodules and roots following the lower Cd2+ treatment, though at the higher Cd2+ concentration root enzyme activity returned to control levels. An impressive increase in enzyme activity was found in nodules. In roots, the glutamine synthetase / glutamate synthase pathway was decreased at the two Cd2+ concentrations, though in nodules it was diminished only at 200 &#956;M Cd2+. No changes in protease activity were found in the two tissues treated with 50 &#956;M Cd2+. However, at 200 &#956;M Cd2+, nodule and root protease activities decreased and increased, respectively. These results suggest that, in general, treatment with Cd2+ affects nitrogen assimilation and metabolism to a greater extent in soybean roots than in nodules. 
ER  -

