Activity of the Photosynthetic Apparatus in Phaseolus vulgaris L. Leaves Under the Cadmium Stress

The development of civilisation, urbanisation and industrialisation cause to ever increasing contamination of the natural environment. Cadmium belongs to this group of chemical elements, which represent a serious threat, not only for the proper development of plants but also for the health of humans and animals. Hence, the interest of scientists in the toxic effects of this kind chemical elements on the various life functions of organisms. The aim of this study was to investigate the effect of cadmium nitrate aqueous solutions on photosynthetic activity and degree of disorganisation of cell membranes in leaves of common bean (Phaseolus vulgaris L. cv. 'Laurina'). A fully formed second leaves were wetted with cadmium solutions nitrate (Cd(NO3)(2)) at concentrations of 5 and 10 mM. With the increasing of cadmium concentration and time of its application (20, 40, 60 min and 24 h), the changes in the fluorescence of bean leaves were observed. Under the influence of cadmium ions, damage occurred both on the edge and the central part of the leaves, and then the whole surface. The highest changes of the chlorophyll fluorescence values were observed after 24 h of application the aqueous cadmium solutions. Use of SPAD chlorophyll Meter, the reduction of chlorophyll content was noticed over time. The flow of electrolytes from the bean leaves was increased with the time and concentration of applied cadmium compounds.