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Wheat plants were grown in field plots of 3×3m area. After growth period of two months, the growing plants were sprayed with dimethoate and pirimicarb at the recommended dose. Spraying was repeated after a further 45 days. Plant samples were taken at intervals of zero, three, six, nine, 12 and 15 days after each application. A gradual and continuous degradation of the applied pesticides had taken place in the treated wheat shoots up to the end of the experiment. However, dimethoate showed more residues and persistence rather than pirimicarb. The break down and metabolism of the applied pesticides was correlated with some biochemical changes in the sprayed plants. Sampling dates of three and six days after application were the most critical periods to affect plant metabolism. A decline was noticed in chlorophyll, sugars and carbohydrates, total proteins and RNA content of wheat shoots as a function of the applied pesticides. Free amino acids were accumulated in the sprayed plants, meanwhile the DNA content did not show observable changes as a consequence of the applied pesticides treatment.

Describes field experiments to determine the effects of previous organic waste composts, using different types and application rates, on sunflower yield. Oil, carbohydrates and metal content were evaluated. Experiments were conducted in the Nuclear Research Centre Farm, in sandy, infertile soil. Results show a remarkable increase in dry matter and seed yields, due to previous single compost additions. A mixture of water hyacinth and biosolid compost showed an improvement. The results of this research indicate that application of organic waste composts is a feasible and valuable recycling method in sandy desert soils.

Pot experiments were conducted to study the effects of different levels of Cobalt (Co), on the growth and on the chemical constituents of peanut plants. Co was added to soil at concentrations of 0, 25, 50, 100, 200 and 400mg Co/kg soil. Dry matter accumulation, chlorophyll content, catalase activity, total proteins and free amino acids content, carbohydrates and sugars and mineral contents were determined in roots, stems and leaves of the plant. Results showed that soil polluted with higher rates of Co depressed plant growth in terms of dry matter production. However, the relatively low levels of Co increased the dry matter accumulation. The results obtained indicated high accumulation of Co in plant, although the level of Co in the soil was added in relatively low concentrations. On the other hand, plant chemical constituents exhibited different responses according to plant organ and Co application rate. In addition, the interaction effect both Co and Ni on the mineral content of peanuts was investigated.

Investigates the assimilation and persistency of ¹⁴C‐parathion in an aqueous culture system. The radioactive pesticide was added to the nutrient medium of both soybean and wheat plants grown under aseptic and controlled conditions. Total applied radioactivity to the nutrient solution of both soybean and wheat were 1670 and 418 Bg, respectively. After 48 hours a balance sheet for the transported and recovered radioactivity was calculated. Turnover rate of the studied pesticide was concluded on the basis of its conversion to polar and non‐polar metabolites, in addition to the non‐extractable residues. Indicates that parathion has moderate persistence in the studied aqueous culture system; most of the applied radioactivity was transported from the nutrient solution and detected in the grown plants; polar metabolites were the predominant fraction in the nutrient solution as well as plant tissues; and in general, p‐nitrophenol was found in comparatively higher proportions as end product rather than paraoxon. Minor differences were evident regarding the metabolic behaviour of the pesticide under investigation in both soybean and wheat cultivating systems.