الفهرس 
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Abstract
Three experiments have been performed to evaluate interactions between cadmium and zinc and their reflection on growth and status of macronutrients in plants under study, through pot experiments followed by field experiment.
5.1. Pot experiments
These were performed to determine plant growth responses to the presence of elements under study and find out the impact on the nutritional status of the concerned plant.
5.1.1. first experiment
The use of soft sand particles with diameter of 0.5 to 1 mm, was performed with the use of a nutrient solution recommended by Hoagland.
5.1.2. Second experiment
Soil samples were taken from the College Shalakan farm; used amounts of urea and mono super phosphate along with potassium sulfate for each pot were as recommended by the Crops Research Institute - Agricultural Research Center.
Results can be summarized as follows: -
1. Cadmium addition to the soil led to growth decrease as its concentration increases in the growth medium; this was more clear in the early growth stages of the studied plants.
2. The addition of zinc to the soil increased the growth of plants under study, but to a certain limit of concentrations; an increased concentration to 20 ppm generally led to deterioration of the growth of plants.
3. The addition of zinc, as one of the necessary elements, to the growth media in which cadmium was added led to increases in the studied growth parameters (fresh and dry weights) in plants.
4. In both sand culture and clay soil experiments, growth was generally improved in case of treatment of plants with concentrations of 10 and 20 ppm zinc in the presence of cadmium; however, growth improvement was observed with treatment of 100 cadmium and 100 zinc ppm in the clay soil more than found with sand culture. This means that the properties of the soil have also impacts on improving growth.
5.2. Field experiment
A study was performed for the application of the results obtained from the pot experiments under field conditions; this attempt was performed through evaluating plant development in response to the presence of elements under study, which included both of cadmium and zinc. This attempt has been carried out at area Al-Gabal Al-Asfar which contains the concerned elements of the two following concentrations:
Cadmium ( total 44.5 ppm and available 3.59 ppm)
Zinc ( total 78.9 ppm and available 8.05 ppm)
It may be worth to mention that the study design included both:
1. normal soil as control
2. soil having plants receiving 10 ppm zinc solution.
The results are summarized as follows:
1- Well plant growth under normal soil conditions, possibly due to the initial presence of available zinc in the soil .
2- Treatments of foliar spray with 10 ppm Zn; more improved the plant growth.