الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Recently, Egypt suffers from an increasing rate of cancer especially among children, many sources of cancer was recorded, important one from these are Electromagnetic fields (EMFs), which produce free-radicals, which travel throughout the body and can cause DNA damage, or produce photons that directly strike the DNA, damaging the structure of DNA in the living cells and produce cancer cells. The aim of this study was to illustrate the possible effect of EMF on plant genes and chromosomes. Therefore, in this study a plant model was used to estimate the possible effect of EMFs on human genes and its side effect on human health and on agriculture. Vicia faba L. plant at seedlings stage was used as it is the most important stage in plant life and any damage in this stage affects the whole plant life. The tested plants were grown under the high voltage cables for Ten days. Plant seedlings were placed at different points around the cables (zerometer, 5 meter and 10 meter in each side). The cellular effects of electromagnetic fields on plant seedlings were evaluated at the cytological, biochemical and molecular levels. For all treatments, controls were a set of seedlings covered by aluminum foil, which limit the effect of the electromagnetic waves as well as seedlings grown in the field at 200 meters from the cables. Several morphological characteristics were selected to evaluate the effect of EMFs on the Vicia faba L. seedling like fresh weight, root length, shoot length, seeds germination percentage and weight of 100seeds.The results of this study revealed that EMFs changed the morphological characters of the Vicia faba L. seedlings compared to control. There was a decrease in growth rates in the seedlings of zero generation, which germinated directly under the high-tension lines and the growth was gradually increased at 5 meters and at 10 meters away from the lines. For example, root length of the seedlings germinated directly under the line recorded the shortest roots length, while the seedlings germinated at 10 left non-covered (10LN) and 10 right non-covered (10RN) recorded the longest root lengths. In addition, EMFs reduced the shoot lengths of the V.faba L. seedlings, the lowest shoot length was recorded at zero distance from the high-tension line (0N). Also, 100 seeds weight was gradually decreased with decreasing the distances from the high-power tension lines, where control seedlings recorded the highest 100 seeds weight, while seedlings germinated directly under the high-power tension lines (0N) exhibited the lowest 100 seeds weight. Cytological analysis revealed that the EMFs have a cytomutagenic effect on chromosomes of secondary roots of V.faba L., where the percentage of abnormalities increased gradually with decreasing distances from the highpower tension line, i.e. the lowest percentage of abnormalities found in control samples, while the highest percentage of abnormalities found at zero (non-covered sample directly under the lines) and at zero (covered sample directly under the lines). Many kinds of abnormalities were found in response to EMFs as c-metaphases, c-anaphases, disturbed prophases, sticky chromosomes, bi-nucleated cells, lagging chromosomes, chromosome bridges, oblique chromosomes and micronuclei. Failure in cytokinesis (abundant in this study) and bi-nucleated cells are considered as strong cytological cancer markers. No cytological or morphological variation between the treated and the control seedlings of the first generation was observed and also no significant variation between covered and non-covered samples was found. Electrophoretic analysis of protein samples showed distinctive electrophoretic patterns. The protein profile of V.faba L. seedlings exhibited 4 monomorphic bands and 3 polymorphic bands with molecular weight ranged from 11 to 245 kDa. The difference between the percentage of polymorphic bands between exposed and unexposed plants was not significant. Calcium binding proteins analysis revealed that EMFs affect these isozymes as there was disappearance of some loci from some treated samples. However, no significant variation between the treated and control samples was found. Inter simple sequence repeats (ISSR) analysis showed genetic variation between the treated samples. ISSR results indicated that the seedlings exposed to EMFs showed a significant difference between DNA patterns of exposed and unexposed V.faba L. Fifteen out of the 18 bands were polymorphic, while the remaining three bands were monomorphic. Cluster analysis based on calcium binding proteins, peroxidase isozyme and malate dehydrogenase isozymes as well as ISSR markers showed that the first-generation samples (M1) are clustered together. Also, the samples germinated directly under the high-power tension line (ZC and ZN) of zero generation (covered and non-covered samples) were clustered together. The dendrogram showed that the samples of each generation were clustered together with low genetic distances. Dendrogram also showed considerable high genetic distances among seedlings grown under the high voltage transmission lines compared to that grown away from power lines, which clustered together with low genetic distances. this study indicated that EMFs have a mutagenic effect on the secondary root tips of faba bean seedlings as it induced many types of abnormalities. Some of these abnormalities, such as bi-nucleated cells are considered as strong cytological markers for cancer. They were found abundant in response to EMFs. In addition, EMFs disturbed isozymes metabolism such as malate dehydrogenase, peroxidase and calcium binding proteins (isozymes), which play important role in calcium metabolism. In addition, ISSR analysis showed that EMFs induced some unique bands in V.faba L. seedlings. It has been found also that the effect of EMFs decreased with increasing the distance from the high-power tension line. This study indicated that 200 meters from the high-power tension lines is considered to be a safe distance. Aluminum sheets reflect electric field but are not very effective at magnetic fields. Also, this study indicated that the effect of EMFs has not inherited in the first generation. Therefore, it seems that EMFs may have a mutagenic effect on the living organism and long exposure time must be avoided.