Browsing by Author "Kohli, R.K."

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24-Epibrassinolide pre-treatment reduces alkaline-induced oxidative stress in red rice seedlings
(Springer, 2019) Sharma, M; Mahajan, P; Singh, H.P; Batish, D.R; Kohli, R.K.
Soil alkalinity caused by salts, such as sodium bicarbonate (NaHCO3), and the frequently associated waterlogging problems are pervasive in agriculture and have a deleterious impact on crop production. However, various plant growth regulators, including brassinosteroids, are considered to be important against different abiotic stresses experienced by plants due to drought, salinity, and heavy metal stress. We investigated the putative role of 24-epibrassinolide (EBL), an active brassinosteroid, on red rice plants experiencing alkaline stress. Seedlings were pre-treated with 0.01 μM EBL for 30 min and later, exposed to NaHCO3 (25 mM) and were sampled, 5 days after treatments. Results showed that the pre-treatment of seedlings with EBL under non-stress conditions could promote rice plant growth. Growth parameters including dry weight (DW), root and coleoptile lengths were reduced under alkaline stress, whereas EBL application reduced the level of inhibition, as compared with NaHCO3 treatment. Enhanced levels of malondialdehyde content, hydrogen peroxide, and superoxide radicals were significantly diminished by EBL pre-treatment. Moreover, pre-treatment of EBL to alkaline-treated rice seedlings largely stimulated the enzymatic activities of ascorbate peroxidase, catalase, and superoxide dismutase. Thus, the results suggest that pre-application of EBL significantly ameliorates alkaline stress in rice. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
Allelopathic Effect of Leaves of Invasive tree Broussonetia papyrifera against some crop plants
(AdhyaBiosciences, 2016) Negi, Anjana; Batish, Daizy R.; Singh, Harminder Pal; Kohli, R.K.
Allelopathic effect of aqueous extracts of leaves of Broussonetia papyrifera (L.) Vent. was studied on germination and seedling growth of Triticum aestivum L. and Oryza sativa L. under laboratory conditions. The seed germination, seedling length, seedling dry weight and total chlorophyll content were reduced with the increasing treatment of concentration (0.5, 1, 2 and 4%) of B. papyrifera leaf extract as compared to the control. The inhibitory effect was more pronounced on the root length than on coleoptile length. The extracts were rich in phenolic compounds, which are the ubiquitous allelochemicals and often implicated in allelopathy. The study concludes that B. papyrifera exhibits allelopathy through the release of phenolics from its leaves.
Allelopathic effect of Pinus roxburghii on an understorey plant, Bidens pilosa
(AdhyaBiosciences, 2016) Sharma, Neel Kanta; Batish, Daizy R.; Singh, Harminder Pal; Kohli, R.K.
Allelopathic effect of Pinus roxburghii was studied on Bidens pilosa through laboratory and greenhouse experiments. The aqueous extracts of green needles, needle litter and bark were found to inhibit germination and initial growth of B. pilosa in laboratory bioassays. The inhibitory effect on germination root length, shoot length and biomass was also observed on amendment of powdered needle litter in soil in greenhouse pots. The inhibitory effect increased with increase in conc. of extracts or amount of litter amended. The amended soil was found to be rich in phenolics, the known potent allelochemics. The study indicates that such interactions may also be operational in forests of P. roxburghii.
Allelopathic potential of essential oil of wild marigold (Tagetes minuta L) against some invasive weeds
(Open Academic Journals Index, 2015) Arora,Komal; Batish, Daizy R.; Singh,Harminder Pal; Kohli, R.K.
Tagetes minuta is an aromatic plant native to Tropical America. It exhibits wide range of biological activity against insects, nematodes, microbes including medicinal properties. It also creates nuisance for agricultural land. This may be attributed to its allelopathic properties. Therefore, the present study investigated the allelopathic potential of volatile oil of T. minuta on other invasive weeds - Chenopodium murale L., Phalaris minor Retz. and Amaranthus viridis L. It was observed that the volatile oil of T. minuta significantly reduced the germination, growth, chlorophyll content and respiratory ability of recipient weeds in a dose dependent manner. Mitotic studies revealed a complete arrest of mitotic activity in cells of treated root tips of Allium cepa with various aberrations like distorted, trinucleolated and binucleated cells. Thus, it can be concluded that the volatile oil of T. minuta shows allelopathic potential on other plants and this property could be further explored for weed management.
Allelopathic potential of needle litter extracts of Pinus roxburghii on germination and early growth of Zea mays and Echinochloa crus-galli
(Indian Journal of Applied Research (IJAR), 2016) Sharma, Neel Kanta; Batish, Daizy R.; Singh, Harminder Pal; Kohli, R.K.
The needle litter of Pinus roxburghii, a common conifer of Himalayan region was investigated for allelopathic potential against crop plant Zea mays and weed Echinochloa crus-galli. The aqueous extracts from litter enhanced the growth of Z. mays slightly at lower concentrations but showed inhibitory effect at higher concentrations. However, the effect on E. crus- galli was inhibitory at all the concentrations. Overall, the effect on the weed species was more pronounced as compared to the crop species. The findings suggest that the litter of P. roxburghii possesses allelopathic potential and can serve as an important bioresource for management of weeds by utilizing the principles of allelopathy. However, further detailed field studies are needed.
Allelopathic Potential of the Essential Oil of Wild Marigold (Tagetes minuta L.) Against Some Invasive Weeds
(The Science Publisher, 2015) Arora, Komal; Batish, Daizy R.; Singh, Harminder Pal; Kohli, R.K.
Tagetes minuta is an aromatic plant native to Tropical America. It exhibits wide range of biological activity against insects, nematodes, microbes including medicinal properties. It also creates nuisance for agricultural land. This may be attributed to its allelopathic properties. Therefore, the present study investigated the allelopathic potential of volatile oil of T. minuta on other invasive weeds - Chenopodium murale L., Phalaris minor Retz. and Amaranthus viridis L. It was observed that the volatile oil of T. minuta significantly reduced the germination, growth, chlorophyll content and respiratory ability of recipient weeds in a dose dependent manner. Mitotic studies revealed a complete arrest of mitotic activity in cells of treated root tips of Allium cepa with various aberrations like distorted, trinucleolated and binucleated cells. Thus, it can be concluded that the volatile oil of T. minuta shows allelopathic potential on other plants and this property could be further explored for weed management.
Alterations in photosynthetic pigments, protein, and carbohydrate metabolism in a wild plant Coronopus didymus L. (Brassicaceae) under lead stress
(Polish Academy of Sciences, 2017) Sidhu, G.P.S.; Singh, H.P.; Batish, Daizy R.; Kohli, R.K.
Coronopus didymus has been emerged as a promising wild, unpalatable plant species to alleviate lead (Pb) from the contaminated soils. This work investigated the hypothesis regarding various metabolic adaptations of C. didymus under lead (Pb) stress. In pot experiments, we assessed the effect of Pb at varied concentrations (500?2900?mg?kg?1) on growth, photosynthetic pigments, alteration of macromolecular (protein and carbohydrate) content, and activities of enzymes like protease, ?-and ?-amylase, peroxidase (POX), and polyphenol oxidase (PPO) in C. didymus for 6?weeks. Results revealed that Pb exposure enhanced the growth, protein, and carbohydrate level, but decreased the leaf pigment concentration and activities of hydrolytic enzymes. The activities of POX and PPO in roots increased progressively by ~337 and 675%, respectively, over the control, at 2900?mg?kg?1 Pb treatment. Likewise, contemporaneous findings were noticed in shoots of C. didymus, strongly indicating its inherent potential to cope Pb-induced stress. Furthermore, the altered plant biochemical status and upregulated metabolic activities of POX and PPO indulged in polyphenol peroxidation elucidate their role in allocating protection and conferring resistance against Pb instigated stress. The current work suggests that stress induced by Pb in C. didymus stimulated the POX and PPO activities which impart a decisive role in detoxification of peaked Pb levels, perhaps, by forming physical barrier or lignifications. ? 2017, Franciszek G?rski Institute of Plant Physiology, Polish Academy of Sciences, Krak
Appraisal of immediate and late effects of mobile phone radiations at 2100 MHz on mitotic activity and DNA integrity in root meristems of Allium cepa
(Springer, 2019) Chandel, S; Kaur, S; Issa, M; Singh, H.P; Batish, D.R; Kohli, R.K.
The present study evaluated the potential of 2100 MHz radiofrequency radiations to act as cytotoxic and genotoxic agent. Fresh onion (Allium cepa L.) roots were exposed to electromagnetic field radiations (EMF-r) for different durations (1 h and 4 h) and evaluated for mitotic index (MI), phase index, chromosomal aberrations, and DNA damage. DNA damage was investigated with the help of the comet assay by assessing various parameters like % head DNA (HDNA), % tail DNA (TDNA), tail moment (TM), and olive tail moment (OTM). Effects of EMF-r exposure were also compared with that of methyl methanesulfonate (MMS; 90 μM), which acted as a positive control. The post-exposure effects of EMF-r after providing the test plants with an acclimatization period of 24 h were also evaluated. Compared to the control, a significant increase in the MI and aberration percentage was recorded upon 4 h of exposure. However, no specific trend of phase index in response to exposure was detected. EMF-r exposure incited DNA damage with a significant decrease in HDNA accompanied by an increase in TDNA upon exposure of 4 h. However, TM and OTM did not change significantly upon exposure as compared to that of control. Analysis of the post-exposure effects of EMF-r did not show any significant change/recovery. 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. © 2019, Springer-Verlag GmbH Austria, part of Springer Nature.
Appraising the role of environment friendly chelants in alleviating lead by Coronopus didymus from Pb-contaminated soils
(Elsevier Ltd, 2017) Sidhu, Gagan Preet Singh; Singh, Harminder Pal; Batish, Daizy R.; Kohli, R.K.
In a screenhouse experiment, we investigated the role of two environment friendly chelants, Ammonium molybdate and EDDS for Pb mobilisation and its extraction by Coronopus didymus under completely randomized controlled conditions. Seedlings of C.?didymus were grown in pots having Pb-contaminated soil (1200 and 2200?mg?kg?1) for 6 weeks. Plants were harvested, 1 week after the addition of A. molybdate and EDDS. Results revealed that A. molybdate and EDDS enhanced the uptake and accumulation of Pb in roots and shoots of C.?didymus. At 2200?mg?kg?1 Pb level, compared to Pb-alone treatment, the maximal concentration of Pb was increased upto ?10% and ?19%, in roots whereas ?8% and ?18%, respectively, in shoots on addition of 2?mmol?kg?1 A. molybdate and EDDS. Additionally, Pb?+?EDDS treatments enhanced the plant biomass and triggered strong antioxidative response, more efficaciously than Pb?+?A. molybdate and Pb-alone treated plants. In this study, EDDS relative to A. molybdate was more efficient in mobilising and extracting Pb from soil. Although, EDDS followed by A. molybdate had good efficacy in mitigating Pb from contaminated soils but C.?didymus itself has the inherent affinity to tolerate and accumulate Pb from contaminated soils and hence in future, can be used either alone or with some other eco-friendly amendments for soil remediation purposes. ? 2017 Elsevier Ltd
Biochemical Adaptations in Zea mays Roots to Short-Term Pb2+ Exposure: ROS Generation and Metabolism
(Springer, 2015) Kaur, Gurpreet; Kaur, Shubhpreet; Singh,Harminder Pal; Batish, Daizy Rani; Kohli, R.K.; Rishi, Valbha
The present study investigated the effect of lead (0, 16, 40 and 80 mg L?1 Pb2+) exposure for 3, 12 and 24 h on root biochemistry in hydroponically grown Zea mays (maize). Pb2+ exposure (80 mg L?1) enhanced malondialdehyde content (239 %�427 %), reactive carbonyl groups (425 %�512 %) and H2O2 (129 %�294 %) accumulation during 3�24 h of treatment, thereby indicating cellular peroxidation and oxidative damage. The quantitative estimations were in accordance with in situ detection of ROS generation (using 2?,7?-dichlorodihydrofluorescein diacetate dye) and H2O2 accumulation. Pb2+ treatment significantly reduced ascorbate and glutathione content during 3�24 h of exposure. On the contrary, levels of non-protein thiols were enhanced by 3�11.8 time over control in response to 16�80 mg L?1 Pb2+ treatment, after 24 h. A dose-dependent induction in ascorbate peroxidase and lipoxygenase enzyme activity was observed in Z. mays roots. The activities of ascorbate-recycling enzymes (dehydroascorbate reductase and monodehydroascorbate reductase) were significantly increased in relation to concentration and duration of Pb2+ treatment. The study concludes that Pb2+-exposure induces ROS-mediated oxidative damage during early period of exposure despite the upregulation of enzymes of ascorbate�glutathione cycle.
Chemical Characterization and Phytotoxicity of Foliar Volatiles and Essential Oil of Callistemon viminalis
(Har Krishan Bhalla and Sons, 2017) Bali, Aditi Shreeya; Batish, Daizy R.; Singh, Harminder Pal; Kaur, Shalinder; Kohli, R.K.
We investigated the chemical composition and phytotoxicity of foliar volatiles (directly released from the macerated leaves) and essential oil extracted from the leaves of Callistemon viminalis against four weed species. Essential oil (EO) and foliar volatiles caused reduction in germination, seedling growth and dry matter accumulation in Bidens pilosa, Cassia occidentalis, Echinochloa crus-galli and Phalaris minor. Bidens pilosa was found to be the most sensitive towards foliar volatiles and EO, whereas C. occidentalis was the least sensitive. The chemical analyses of foliar volatiles and EO revealed the presence of 1,8-cineole and ?-pinene as the main monoterpenes. The study concludes that volatile components of C. viminalis possess phytotoxicity against weeds and thus may hold promise for the management of weeds under sustainable agriculture. ? 2017, Har Krishan Bhalla & Sons.
Chemical profiling, cytotoxicity and phytotoxicity of foliar volatiles of Hyptis suaveolens
(Academic Press, 2019) Sharma, A; Singh, H.P; Batish, D.R; Kohli, R.K.
In the present study, the essential oil (EO) of Hyptis suaveolens has been explored for the first time for its phytotoxic and cytotoxic activities. The phytotoxic activity was assessed against rice (Oryza sativa) and its major troublesome weed, Echinochloa crus-galli, under laboratory and screenhouse conditions. GC-MS analysis revealed EO to be monoterpenoid (~ 79% monoterpenes) in nature with α-phellandrene (22.8%), α-pinene (10.1%) and limonene (8.5%) as the major chemical constituents. The laboratory bioassay showed a complete growth inhibitory effect of EO (≥ 2 mg mL −1 ) towards the germination and seedling growth of E. crus-galli. However, the inhibitory effect on rice was much less (~40% inhibition). EO caused visible injury, reduction in chlorophyll content, cell viability and ultimately led to complete wilting of E. crus-galli plants. In addition, EO altered the cell division in the meristematic cells of Allium cepa as depicted by ~63% decrease in mitotic index. EO exposure induced several aberrations at chromosomal (c-mitosis, anaphase bridges, chromosomal breakage, vagrant chromosomes, and sticky chromosomes) and cytological level (cytoplasm destruction, peripheral nuclei, and bi-nucleate cells). The present study concludes that H. suaveolens EO possesses phytotoxic activity due to its mito-depressive activity, and could serve as a natural herbicide under sustainable agricultural practices. © 2018 Elsevier Inc.
Climate change and biodiversity: Analysis of the policy framework
(IOS Press, 2014) Gupta, H.; Kohli, R.K.; Ahluwalia, A.S.; Pal, P.
ASEAN countries are highly vulnerable to climate change and loss of biodiversity as a large proportion of their population is concentrated along coastlines, and heavily reliant on agriculture, natural resources and forestry for livelihoods. Seven of the ten countries have ratied both the UNFCCC and CBD, but they have been slow in taking up individual stands at CoP meetings. Three ASEAN countries are megabiodiverse. ASEAN countries were quick in framing and implementing domestic policies on conservation and climate change. One reason for this is that they preferred to go along with the G-77/China group during the negotiations. However, they have been more willing to take collective positions in CBD than in UNFCCC. ASEAN is pursuing a broad-based approach in taking voluntary mitigation and adaptation measures
Comparative account of allelopathic potential of essential oil of Tagetes minuta L. and its major component cis-β-Ocimene
(AdhyaBiosciences, 2016) Arora, Komal; Batish, Daizy R.; Singh, Harminder Pal; Kohli, R.K.
The study aims to explore the chemical composition of volatile essential oil of Tagetes minuta and comparison of its allelopathic potential with cis-β-ocimene, a major component of oil. T. minuta L. is an exotic aromatic plant found growing in northern plains and western Himalayas in India. The water distilled essential oil from aerial parts of T. minuta (at flowering stage) was analyzed by GC-MS. The analysis revealed 27 compounds representing 95.73% of the oil. cis-b-Ocimene (44.56%), dihydrotagetone (28.52%), limonene (3.99%) and tagetone (7.42%) were its major compounds. A comparison of allelopathic effect of cis-b-ocimene was made with T. minuta oil using Cassia occidentalis L., a common wasteland weed, as test plant. Laboratory study included growth studies in the form of germination, seedling length and dry weight of test plant under both treatments i.e. T. minuta oil and cis-b-ocimene. The inhibitory effect of ocimene was more significant as compared to oil. However, highest concentration (20µg/cc) of both treatments was found to be inhibitory with
Effect of lead on oxidative status, antioxidative response and metal accumulation in Coronopus didymus
(Elsevier Masson SAS, 2016) Sidhu, Gagan Preet Singh; Singh, Harminder Pal; Batish, Daizy R.; Kohli, R.K.
A screenhouse experiment was conducted to assay the effect of Lead (Pb) on oxidative status, antioxidative response and metal accumulation in Coronopus didymus after 6 weeks. Results revealed a good Pb tolerance and accumulation potential of C. didymus towards the increasing Pb concentrations (500, 900, 1800, 2900 mg kg-1) in soil. The content of Pb in roots and shoots elevated with higher Pb levels and reached a maximum of 3684.3 mg kg-1 and 862.8 mg kg-1 Pb dry weight, respectively, at 2900 mg kg-1 treatment. Pb exposure stimulated electrolyte leakage, H2O2 level, MDA content and the activities of antioxidant machinery (SOD, CAT, APX, GPX and GR). However, at the highest Pb concentration, the activities of SOD and CAT declined. The H2O2 level and MDA content in roots increased significantly up to ~500% and 213%, respectively, over the control, at 2900 mg kg-1 Pb treatment. Likewise, concurrent findings were noticed in shoots of C. didymus, with the increasing Pb concentration. The present work suggests that C. didymus exhibited a good accumulation potential for Pb and can tolerate Pb-induced oxidative stress by an effective antioxidant defense mechanism. ? 2016.
EMF radiations (1800 MHz)-inhibited early seedling growth of maize (Zea mays) involves alterations in starch and sucrose metabolism
(Springer, 2016) Kumar, Arvind; Singh, Harminder Pal; Batish, Daizy R.; Kaur, Shalinder; Kohli, R.K.
The present study investigated the impact of 1800-MHz electromagnetic field radiations (EMF-r), widely used in mobile communication, on the growth and activity of starch-, sucrose-, and phosphate-hydrolyzing enzymes in Zea mays seedlings. We exposed Z. mays to modulated continuous wave homogenous EMF-r at specific absorption rate (SAR) of 1.69±0.0 × 10−1 W kg−1 for ½, 1, 2, and 4 h. The analysis of seedlings after 7 days revealed that short-term exposure did not induce any significant change, while longer exposure of 4 h caused significant growth and biochemical alterations. There was a reduction in the root and coleoptile length with more pronounced effect on coleoptile growth (23 % reduction on 4-h exposure). The contents of photosynthetic pigments and total carbohydrates declined by 13 and 18 %, respectively, in 4-h exposure treatments compared to unexposed control. The activity of starch-hydrolyzing enzymes—α- and β-amylases—increased by ∼92 and 94 %, respectively, at an exposure duration of 4 h, over that in the control. In response to 4-h exposure treatment, the activity of sucrolytic enzymes—acid invertases and alkaline invertases—was increased by 88 and 266 %, whereas the specific activities of phosphohydrolytic enzymes (acid phosphatases and alkaline phosphatases) showed initial increase up to ≤2 h duration and then declined at >2 h exposure duration. The study concludes that EMF-r-inhibited seedling growth of Z. mays involves interference with starch and sucrose metabolism.
Ethylenediamine disuccinic acid enhanced phytoextraction of nickel from contaminated soils using Coronopus didymus (L.) Sm.
(Elsevier Ltd, 2018) Sidhu, G.P.S.; Bali, A.S.; Singh, H.P.; Batish, Daizy R.; Kohli, R.K.
In a screenhouse, the applicability of biodegradable chelant ethylenediamine disuccinic acid (EDDS) to enhance Ni-phytoextraction by Coronopus didymus was tested for the first time. This study assayed the hypothesis based upon the role of EDDS on physiological and biochemical alterations and ameliorating phytoextraction capacity of C. didymus under nickel (Ni) stress. Pot experiments were conducted for 6 weeks and C. didymus plants were cultivated in soil artificially contaminated with 30, 50, and 70 mg kg?1 Ni treatments. Soil was amended with EDDS (2 mmol kg?1). Plants were harvested, 1 week after EDDS application. At 70 mg kg?1 Ni level, EDDS application dramatically enhanced the root and shoot Ni concentration from 665 and 644 to 1339 and 1338 mg kg?1, respectively. Combination of Ni + EDDS induced alterations in biochemical parameters of plants. EDDS addition posed pessimistic effects on growth, biomass, photosynthetic activity and protein content of the plants. Besides, application of EDDS stimulated the generation of superoxide anion, H2O2 content and MDA level. However, EDDS assisted mount in antioxidant activities (superoxide dismutase, catalase and glutathione peroxidase) considerably neutralised the toxicity induced by reactive oxygen species in plant tissues. The results revealed EDDS efficacy to ameliorate the performance of antioxidant enzymes and improved Ni translocation in plant tissues, thus strongly marked its affinity to be used together with C. didymus for Ni-phytoextraction. ? 2018 Elsevier Ltd
Exogenous Nitric Oxide (NO) interferes with lead (Pb)-induced toxicity by detoxifying reactive oxygen species in hydroponically grown wheat (Triticum aestivum) roots
(Public Library of Science, 2015) Kaur, Gurpreet; Singh, Harminder Pal; Daizy R. Batish; Mahajan, Priyanka; Kohli, R.K.; Valbha, Rishi
Nitric Oxide (NO) is a bioactive signaling molecule that mediates a variety of biotic and abiotic stresses. The present study investigated the role of NO (as SNP [sodium nitroprusside]) in ameliorating lead (Pb)-toxicity in Triticum aestivum (wheat) roots. Pb (50 and 250 ?M) alone and in combination with SNP (100 ?M) was given to hydroponically grown wheat roots for a period of 0-8 h. NO supplementation reduced the accumulation of oxidative stress markers (malondialdehyde, conjugated dienes, hydroxyl ions and superoxide anion) and decreased the antioxidant enzyme activity in wheat roots particularly up to 6 h, thereby suggesting its role as an antioxidant. NO ameliorated Pb-induced membrane damage in wheat roots as evidenced by decreased ion-leakage and in situ histochemical localization. Pb-exposure significantly decreased in vivo NO level. The study concludes that exogenous NO partially ameliorates Pb-toxicity, but could not restore the plant growth on prolonged Pb-exposure. ? 2015 Kaur et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Exogenous nitric oxide (NO) interferes with lead (pb)-induced toxicity by detoxifying reactive oxygen species in hydroponically grown wheat (Triticum aestivum) roots,
(PLOS ONE, 2015) Kaur, Gurpreet; Singh, Harminder Pal; Batish, Daizy R.; Kohli, R.K.; Rishi, Valbha
Nitric Oxide (NO) is a bioactive signaling molecule that mediates a variety of biotic and abiotic stresses. The present study investigated the role of NO (as SNP [sodium nitroprusside]) in ameliorating lead (Pb)-toxicity in Triticum aestivum (wheat) roots. Pb (50 and 250 ?M) alone and in combination with SNP (100 ?M) was given to hydroponically grown wheat roots for a period of 0�8 h. NO supplementation reduced the accumulation of oxidative stress markers (malondialdehyde, conjugated dienes, hydroxyl ions and superoxide anion) and decreased the antioxidant enzyme activity in wheat roots particularly up to 6 h, thereby suggesting its role as an antioxidant. NO ameliorated Pb-induced membrane damage in wheat roots as evidenced by decreased ion-leakage and in situ histochemical localization. Pb-exposure significantly decreased in vivo NO level. The study concludes that exogenous NO partially ameliorates Pb-toxicity, but could not restore the plant growth on prolonged Pb-exposure.
Exposure to mobile phone radiations at 2350 MHz incites cyto- and genotoxic effects in root meristems of Allium cepa
(BioMed Central Ltd., 2019) Chandel, S; Kaur, S; Issa, M; Singh, H.P; Batish, D.R; Kohli, R.K.
Background: The exponential increase of electromagnetic field radiations (EMF-r) in the natural environment has raked up the controversies regarding their biological effects. Concern regarding the putative capacity of EMF-r to affect living beings has been growing due to the ongoing elevation in the use of high frequency EMF-r in communication systems, e.g. Mobile phones. Methods: In the present study, we tried to examine the cyto- and genotoxic potential of mobile phone EMF-r at 2350 MHz using onions (Allium cepa L.). Fresh adventitious onion roots were exposed to continuous EMF-r at 2350 MHz for different time periods (1 h, 2 h and 4 h). The evaluation of cytotoxicity was done in terms of mitotic index (MI), phase index and chromosomal aberrations. Genotoxicity was investigated employing comet assay in terms of changes in % HDNA (head DNA) and % TDNA (tail DNA), TM (tail moment) and OTM (olive tail moment). Data were analyzed using one-way ANOVA and mean values were separated using post hoc Tukey's test. Results: The results manifested a significant increase of MI and chromosomal aberrations (%) upon 4 h, and ≥ 2 h of exposure, respectively, as compared to the control. No specific changes in phase index in response to EMF-r exposure were observed. The % HDNA and % TDNA values exhibited significant changes in contrast to that of control upon 2 h and 4 h of exposure, respectively. However, TM and OTM did not change significantly. Conclusions: 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. © 2019 Springer Nature Switzerland AG.