الفهرس | Only 14 pages are availabe for public view |
Abstract Iron is one of the nutrients necessary for plant growth, but it faces many problems when added to alkaline or alkaline soils. It is also available in a commercial form with a high cost, such as soluble fertilizers. Hence, searching for a formes of iron with high efficiency on one hand and less cost on the other hand will play an important role in providing the needs of plants. Recently, nano-fertilizers are considered one of the highly efficient forms of providing iron to plants. The processing of nano iron by environmentally friendly methods has become possible and has good economic feasibility compared to chelated iron fertilizers. This thesis aims to prepare a nano-iron fertilizer using a number of plant extracts (leaves of guava, olive and purslane) or extracts of plant residues (such as black tea bagasse) because these extracts contain compounds and active substances with a high ability to synthesize iron nanoparticles. The extracts contain antioxidants and active substances that have a great role in reducing traditional iron compounds such as ferrous sulfate and ferric chloride and preserving them in nano form for long periods. To achieve the objectives of this study, namely: the possibility of synthesis of iron nanoparticles using the above-mentioned plant extracts (known as phytochemicals) and ferrous sulfate salts as an iron source, and testing the use of nano-synthesized iron as a foliar spray fertilizer on tomato plants compared to conventional fertilizers (ferrous sulfate) and chelated fertilizers (EDTA-Fe). Olive tree leaves, guava leaves and purslane were brought from some farms in the Nubaria area - Buhaira governorate. Quantities of black tea waste were also collected and aqueous extracts were made from these sources after processing and prepared for aqueous extraction, and then those extracts were reacted with ferrous sulfate solution to obtain nanoscale iron oxide. After that, the confirmed properties of obtaining nano-iron were identified by transmission electron microscopy (TEM), FTIR, and spectrophotometric measurement to measure the stability of the formed nano-iron. The second part of the study After obtaining nano-iron and identifying its properties, then conducting an experiment to grow tomatoes in pots, where pots containing 10 kg of calcareous soil were prepared and basic fertilizers were added from phosphorous (mono superphosphate) and potassium (potassium sulfate) in the recommended batches and then transferred Tomato seedlings to the pots and irrigate them with tap water. The ammonium nitrate was also fertilized and the recommended amount was divided into 3 batches over the time period of planting until harvest. After 15 days of transplanting, the plants were sprayed with a solution of nano-iron, conventional iron (ferrous sulfate) and chelated iron (EDTAFe) at concentrations of zero, 50 and 100 mg L-1, and the spraying was repeated three times every 15 days. At harvest, a number of measurements were determined, such as plant height, fresh and dry weight of stems, leaves and fruits, as well as the number of fruits. The results of the nano iron formed as a result of the interaction of aqueous extracts with ferrous sulfate showed the ability of black tea residues to form a large amount of hexagonal iron oxide (hematite) during the first minutes of the reaction and then the guava leaf extract, but in somewhat smaller quantities than those formed with tea residues. While the reaction of the aqueous extract of olive leaves and purslane with ferrous sulfate showed a lower ability to form nano iron and a much longer time to start forming nano iron. The results of identifying the properties of the formed nano iron exhibited that the formed iron is a hexagonal iron oxide mineral or what is known as hematite from the results of X-ray scattering tests. The stability results of iron nanoparticles also revealed that 58 hematite nanoparticles have a high degree of stability through the values of the obtained curves peaks. |