An-Najah Staff

Several factors affecting the growth and the metal uptake of pepper plants treated with cadmium solutions have been studied. These include concentration of cadmium, type of treatment, type of soil, plant species, and some properties of solutions used for treatment such as acidity, degree of salinity and temperature.
Cadmium had an obvious effect on the growth of pepper plants. Foliar‐treated plants were affected more than root‐treated plants. The least degree of growth‐inhibition and of cadmium uptake was found in plants grown in soils with high organic matter content. Various species of pepper plants acted very differently towards cadmium treatment. Both growth‐inhibition and cadmium uptake was increased in plants treated with acidic, saline and hot solutions.

Several factors affecting the growth and the uptake of cadmium by okra plants were studied using both root ‐ treatment and foliar ‐ treatment. These factors were the concentration of cadmium , type of treatment, soil composition, presence of foreign ions, salinity, acidity and temperature.
Both growth of plant and cadmium uptake by plant were affected highly by the concentration of cadmium, type of treatment, soil composition, salinity and temperature. Acidity of solutions has only a little and irregular effect. A synergistic combined effect of lead, copper and zinc with cadmium was observed on the growth of plant but not regular on the uptake of cadmium.

The effect of root‐treatment of cauliflower, spinach, and parsley plants with lead and cadmium were studied. Both metal ions showed obvious growth inhibition of treated plants with cadmium having higher toxicity on growth than lead.
Cadmium was more concentrated in the edible parts of the three treated plants whereas lead was more concentrated in the edible parts of cauliflower and spinach plants only.
Metal ion concentrations and total metal ion content of treated plants increased with the increase of concentration of cadmium or lead ions in solutions used for treatment. The uptake of metal ion per unit concentration decreased in treated plants with the increase of concentration of cadmium or lead ions in solutions used for treatment.
Metal ion concentration and metal uptake were higher in the plants treated with cadmium than those treated with lead.

Toxicity of cadmium and lead on the growth of carrot plants has been studied. Cadmium has been found to be more toxic than lead especially on the shoots of carrot plants.
Foliar treatment has been compared with root‐treatment for the two elements on carrots and on their roots and shoots.
Concentrations and total contents of lead and cadmium in whole plant in roots and in shoots have been determined for treated carrot plants and compared in root‐treatment with foliar‐treatment. Explanations have been suggested whenever possible to illucidate the results obtained.
Percentages of the metals taken by plants from the whole amounts of metal added during treatment have been calculated and related to type of metal used, concentration of metal in solutions used for treatment and the way of treatment.