5383
SAMAH MOSTAFA EL-SAYED
THE EFFECT OF BIOSTIMULANTS ON REDUCING THE HAZARDS EFFECT OF HEAVY METALS ON SOME WOODY TREES
Khaya senegalensis, Eucalyptus gomphocephala, L-Tryptophan, mycorrhiza fungi, cadmium chloride.
This study was carried out in the Experimental Field of the Ornamental Horticulture Department, Faculty of Agriculture, Cairo University, during the two successive seasons of 2014 and 2015. The laboratory work was conducted in the Ornamental and Woody Trees Department, National Research Centre. The aim of this work was to study reducing the harmful effect of cadmium soil pollution on the growth of Khaya senegalensis and Eucalyptus gomphocephala plants by using mycorrhiza fungi or L-Tryptophan (L-Trp) at different rates. The plants were transplanted in 30cm plastic pots filled with mix of clay and sand (1:1 by volume) and were treated with Cd as cadmium chloride (CdCl2.H2O) at four concentration(0, 50, 100 and 200ppm). The three rates of mycorrhiza fungi (0, 5 and 10g/pot) was mixed with the soil before transplanting. The plants were sprayed twice with L-Trp at the concentrations of (0, 100 and 200ppm) the first was applied one month after transplanting, the second one was one month later. The recorded results on K. senegalensis showed that Cd at 200ppm significantly decreased all the vegetative characterstics and chemical composition except the content of Cd in all parts of plant and the content of proline and isozyme expression of catalase in leaves which increased. The biostimulants treatments had a stimulant effect on K. senegalensis especially mycorrhiza fungi treatment at the rate of 10g/ pot which increased the all vegetative and chemical characterstics. Also the treatment of mycorrhiza fungi at the rate of 10g/ pot had an enhancement effect on K. senegalensis plants grown in soil polluted with Cd at different concentrations. The recorded results on Eucalyptus gomphocephala plant indicated that the vegetative characterstics and chemical composition decreased gradually by increasing Cd concentration in the soil except proline and Cd content and isozyme catalase expression. It is noticed that vegetative characterstics were significantly affected by L-Trp at the concentration of 100ppm alone or combined with Cd except leaf area and root length which were increased by treatment mycorrhiza fungi at the rate of 10g/pot alone or combined with Cd, whereas, the fresh and dry weight of roots increased by treatment L-Trp at 200ppm alone or combined with Cd. While the chemical composition increased by the treatment of L-Trp at the concentration of 100ppm alone or combined with Cd except total hydrolysable carbohydrate(%),P (%) and Cd content in all plant parts were increased by treatment of mycorrhiza fungi at the rate of 10g/pot alone or combined with Cd.
2017
Ph.d
Cairo
Agriculture