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"Although exposure to low frequency electromagnetic radiation is harmful to plants, LF-EM irradiated Nerium oleander seedlings exhibited enhanced development and growth, probably taking advantage of defined structural leaf deformations. Currently, evidence supports the undesirable, often destructive impact of low frequency electromagnetic (LF-EM) radiation on plants. The response of plants to LF-EM radiation often entails induction in the biosynthesis of secondary metabolites, a subject matter that is well documented. Nerium oleander is a Mediterranean plant species, which evolved remarkable resistance to various environmental stress conditions. In the current investigation, cultivated N. oleander plants, following their long-term exposure to LF-EM radiation, exhibited major structural modifications as the flattening of crypts, the elimination of trichomes and the reduction of the layers of the epidermal cells. These changes co-existed with an oxidative stress response manifested by a significant increase in reactive oxygen species at both the roots and the above ground parts, a decline in the absorbance of light by photosynthetic pigments and the substantially increased biosynthesis of L-Dopa decarboxylase (DDC), an enzyme catalyzing the production of secondary metabolites that alleviate stress. The exposed plants exhibited greater primary plant productivity, despite a manifested photosynthetic pigment limitation and the severe oxidative stress. This unique response of N. oleander to severe abiotic stress conditions may be owed to the advantage offered by a structural change consistent to an easier diffusion of CO2 within the leaves. A major plant response to an emerging "pollutant" was documented."
"Our data, thus, suggest the potential cytotoxic and genotoxic nature of 2100 MHz EMF-r. Our study bears great significance in view of the swiftly emergent EMF-r in the surrounding environment and their potential for inciting aberrations at the chromosomal level, thus posing a genetic hazard."
"We report for the first time that short treatments of sunflower seeds induce stressor specific pattern of changes in the content of seed phytohormones involved in the control of germination: vacuum treatment affected auxin/cytokinin balance; CP treatments substantially increased gibberellin content while other effects varied with treatment duration; EMF treatment was effective in decreasing abscisic acid content. Such a finding indicates that despite high resistance to environmental stresses in a dehydrated state, seeds rapidly respond even to short pre-sowing treatments with physical stressors on the level of phytohormone balance. Our results show that exposure of seeds to radio-frequency EMF or CP could induce a similar long-term effect on gene expression and the development of germinated plants suggesting that radio frequency radiation component of CP and EMF could be the main cause of the observed effect."
"Our results infer that continuous exposures of radiofrequency EMF-r (2350 MHz) for long durations have a potential of inciting cyto- and genotoxic effects in onion root meristems."
"However, public exposure regulations in most countries continue to be based on the guidelines of the International Commission on Non-Ionizing Radiation Protection and Institute of Electrical and Electronics Engineers, which were established in the 1990s on the belief that only acute thermal effects are hazardous. Prevention of tissue heating by radiofrequency electromagnetic radiation is now proven to be ineffective in preventing biochemical and physiological interference. For example, acute non-thermal exposure has been shown to alter human brain metabolism by NIH scientists, electrical activity in the brain, and systemic immune responses. Chronic exposure has been associated with increased oxidative stress and DNA damage and cancer risk. Laboratory studies, including large rodent studies by the US National Toxicology Program and Ramazzini Institute of Italy, confirm these biological and health effects in vivo."
"The study concluded that 2100 MHz cell phone EMF-r incite oxidative damage in onion roots by altering the oxidative metabolism."
"The study concluded that 2100 MHz cell phone EMF-r incite oxidative damage in onion roots by altering the oxidative metabolism."
"In this article, we observed the effects of Wi-Fi radiation on the growth plants, namely garden cress. One sample was exposed to long-term electromagnetic radiation in the vicinity of Wi-Fi router. The second sample was exposed minimum to that radiation. It has been shown that long-term exposure of Wi-Fi radiation in the vicinity of the cress causes changes in growth and development as well as visible changes of discoloration and vitality."
"SUBJECT AND METHODS:
In this study, we performed an analysis of the data extracted from the 45 peer-reviewed scientific publications (1996-2016) describing 169 experimental observations to detect the physiological and morphological changes in plants due to the non-thermal RF-EMF effects from mobile phone radiation. Twenty-nine different species of plants were considered in this work.
RESULTS:
Our analysis demonstrates that the data from a substantial amount of the studies on RF-EMFs from mobile phones show physiological and/or morphological effects (89.9%, p < 0.001). Additionally, our analysis of the results from these reported studies demonstrates that the maize, roselle, pea, fenugreek, duckweeds, tomato, onions and mungbean plants seem to be very sensitive to RF-EMFs. Our findings also suggest that plants seem to be more responsive to certain frequencies, especially the frequencies between (i) 800 and 1500 MHz (p < 0.0001), (ii) 1500 and 2400 MHz (p < 0.0001) and (iii) 3500 and 8000 MHz (p = 0.0161)."
"The measurements of all trees revealed significant differences between the damaged side facing a phone mast and the opposite side, as well as differences between the exposed side of damaged trees and all other groups of trees in both sides. Thus, we found that side differences in measured values of power flux density corresponded to side differences in damage. The 30 selected trees in low radiation areas (no visual contact to any phone mast and power flux density under 50μW/m2) showed no damage. Statistical analysis demonstrated that electromagnetic radiation from mobile phone masts is harmful for trees. These results are consistent with the fact that damage afflicted on trees by mobile phone towers usually start on one side, extending to the whole tree over time."
"The results suggest that treatment with electromagnetic field stimulated germination of freshly harvested R. smirnowii seeds (increased germination percentage up to 70%), but reduced germination of fresh M. nigra seeds (by 24%)."
"Soybean seedlings were also exposed for 5 days to an extremely low level of radiation (GSM 900 MHz, 0.56 Vm(-1)) and outgrowth was studied 2 days later. Growth of epicotyl and hypocotyl was found to be reduced, whereas the outgrowth of roots was stimulated. Our findings indicate that the observed effects were significantly dependent on field strength as well as amplitude modulation of the applied field."
"The results indicated that exposure to EMR causes a change in the non-photochemical quenching of the duckweeds. The changes varied with the frequency of the EMR and were time-varying within a particular frequency. The temperature remained unchanged in the duckweed fronds upon exposure to EMR, which confirms that the effect is non-thermal."
"Here we studied the influence of microwave irradiation at bands corresponding to wireless router (WLAN) and mobile devices (GSM) on leaf anatomy, essential oil content and volatile emissions in Petroselinum crispum, Apium graveolens and Anethum graveolens. Microwave irradiation resulted in thinner cell walls, smaller chloroplasts and mitochondria, and enhanced emissions of volatile compounds, in particular, monoterpenes and green leaf volatiles (GLV). These effects were stronger for WLAN-frequency microwaves. Essential oil content was enhanced by GSM-frequency microwaves, but the effect of WLAN-frequency microwaves was inhibitory. There was a direct relationship between microwave-induced structural and chemical modifications of the three plant species studied. These data collectively demonstrate that human-generated microwave pollution can potentially constitute a stress to the plants."
"In conclusion, this review has found that it is necessary to rethink EMR exposure guidelines, including those endorsed by FCC and ICNIRP, as most studies addressing the effects of microwave on animals and plants have documented effects and responses at exposures below the limits specified in these guidelines. The present
EMR guidelines are based on heating effects, and it will be
necessary to consider the nonthermal effects that have been confirmed in the published literature in the preparation of future guidelines."
"Exposure to alpha-radiation from plutonium-239 and exposure to modulated radiation from mobile phone during 3 and 9h significantly increased the mitotic index. GSM 900 mobile phone radiation as well as alpha-radiation from plutonium-239 induced both clastogenic and aneugenic effects. However, the aneugenic activity of mobile phone radiation was more pronounced. After 9h of exposure to mobile phone radiation, polyploid cells, three-groups metaphases, amitoses and some unspecified abnormalities were detected, which were not registered in the other experimental groups. Importantly, GSM 900 mobile phone radiation increased the mitotic index, the frequency of mitotic and chromosome abnormalities, and the micronucleus frequency in a time-dependent manner. Due to its sensitivity, the A. cepa test can be recommended as a useful cytogenetic assay to assess cytotoxic and genotoxic effects of radiofrequency electromagnetic fields."
"The review of existing literature shows that the EMRs are interfering with the biological systems in more ways than one and there had already been some warning bells sounded in the case on bees (Warnke 2007; vanEngelsdorp et al.2010; Gould 1980; Sharma and Neelima R Kumar 2010) and birds, which probably heralds the seriousness of this issue and indicates the vulnerability of other species as well. Despite a few reassuring reports (Galloni et al.2005), a vast majority of published literature indicate deleterious effects of EMFs in various species. The window of frequency range and exposure time required to make measurable impacts would vary widely among species and unfortunately we do not have any such data available for most of our free-living floral and faunal species in India. There is an urgent need to focus more scientific attention to this area before it would be too late."
"Cell phone EMF radiations significantly reduced the seedling length and dry weight of V radiata after exposure for 0.5, 1, 2, and 4 h. Furthermore, the contents of proteins and carbohydrates were reduced in EMF-exposed plants. However, the activities of proteases, alpha-amylases, beta-amylases, polyphenol oxidases, and peroxidases were enhanced in EMF-exposed radicles indicating their role in providing protection against EMF-induced stress. The study concludes that cell phone EMFs impair early growth of V radiata seedlings by inducing biochemical changes."
"Our results showed that cell phone EMFr significantly inhibited the germination (at > or =2 h), and radicle and plumule growths (> or =1 h) in mung bean in a time-dependent manner. Further, cell phone EMFr enhanced MDA content (indicating lipid peroxidation), and increased H(2)O(2) accumulation and root oxidizability in mung bean roots, thereby inducing oxidative stress and cellular damage. In response to EMFr, there was a significant upregulation in the activities of scavenging enzymes, such as superoxide dismutases, ascorbate peroxidases, guaiacol peroxidases, catalases and glutathione reductases, in mung bean roots. The study concluded that cell phone EMFr inhibit root growth of mung bean by inducing ROS-generated oxidative stress despite increased activities of antioxidant enzymes."
"A review on the impact of radiofrequency radiation from wireless telecommunications on wildlife is presented. Electromagnetic radiation is a form of environmental pollution which may hurt wildlife. Phone masts located in their living areas are irradiating continuously some species that could suffer long-term effects, like reduction of their natural defenses, deterioration of their health, problems in reproduction and reduction of their useful territory through habitat deterioration. Electromagnetic radiation can exert an aversive behavioral response in rats, bats and birds such as sparrows. Therefore microwave and radiofrequency pollution constitutes a potential cause for the decline of animal populations and deterioration of health of plants living near phone masts. To measure these effects urgent specific studies are necessary."
"Our results show that non-thermal exposure to the radiofrequency fields investigated here can induce mitotic aberrations in root meristematic cells of A. cepa. The observed effects were markedly dependent on the field frequencies applied as well as on field strength and modulation. Our findings also indicate that mitotic effects of RF-EMF could be due to impairment of the mitotic spindle."
"Our results showed that non-thermal exposure to investigated radiofrequency fields induced oxidative stress in duckweed as well as unspecific stress responses, especially of antioxidative enzymes. However, the observed effects markedly depended on the field frequencies applied as well as on other exposure parameters (strength, modulation and exposure time). Enhanced lipid peroxidation and H(2)O(2) content accompanied by diminished antioxidative enzymes activity caused by exposure to investigated EMFs, especially at 900 MHz, indicate that oxidative stress could partly be due to changed activities of antioxidative enzymes."
"Transcript accumulation was maximal at normal Ca(2+) levels and was depressed at higher Ca(2+), especially for those encoding calcium-binding proteins. Removal of Ca(2+) (by addition of chelating agents or Ca(2+) channel blocker) led to total suppression of mRNA accumulation. Finally, 30 min after the electromagnetic treatment, ATP concentration and adenylate energy charge were transiently decreased, while transcript accumulation was totally prevented by application of the uncoupling reagent, CCCP. These responses occur very soon after exposure, strongly suggesting that they are the direct consequence of application of radio-frequency fields and their similarities to wound responses strongly suggests that this radiation is perceived by plants as an injurious stimulus."
"Our results tend to show a direct relationship between HF‐EMF exposure of tomato plants and responses at the level of gene expression. Although not identical, the kinetics and amplitudes (three‐ to seven‐fold increases) of the targeted transcripts showed striking similarities with the previously described physiologic responses following injurious treatments such as leaf flaming or electrical stimulation (Stankovic and Davies 1997, Vian et al. 1999). Accordingly, we propose here that HF‐EMF exposure may constitute an environmental stimulus for the tomato plants."
"The physiological impact of nonionizing radiation has long been considered negligible. However, here we use a carefully calibrated stimulation system that mimics the characteristics (isotropy and homogeneity) of electromagnetic fields present in the environment to measure changes in a molecular marker (mRNA encoding the stress-related bZIP transcription factor), and show that low amplitude, short duration, 900 MHz EMF evokes the accumulation of this mRNA. Accumulation is rapid (peaking 5–15 min after stimulation) and strong (3.5-fold), and is similar to that evoked by mechanical stimulations."
"The growth of plants exposed for 2 h to the 23 V/m electric field of 900 MHz significantly decreased in comparison with the control, while an electric field of the same strength but at 400 MHz did not have such effect. A modulated field at 900 MHz strongly inhibited the growth, while at 400 MHz modulation did not influence the growth significantly. At both frequencies a longer exposure mostly decreased the growth and the highest electric field (390 V/m) strongly inhibited the growth. Exposure of plants to lower field strength (10 V/m) for 14 h caused significant decrease at 400 and 1900 MHz while 900 MHz did not influence the growth. Peroxidase activity in exposed plants varied, depending on the exposure characteristics. Observed changes were mostly small, except in plants exposed for 2 h to 41 V/m at 900 MHz where a significant increase (41%) was found. Our results suggest that investigated electromagnetic fields (EMFs) might influence plant growth and, to some extent, peroxidase activity. However, the effects of EMFs strongly depended on the characteristics of the field exposure."