Chromosomes and Mitotic Cell Division Phase In Onion Roots After 24 Hours Acetoorcein Soaking Time

Onions (Allium cepa) are usually used in vitro to assess effect of chemical subtances by allowing developing roots to come into contact with substances to be tested. Acetic orcein staining of onion chromosomes has remained a standard method of preparation. However, aceto-orcein stain is corrosive and poisonous chemical substances since it containing oxidising agents such as organic peroxides, the toxic substances which are are cyanides, acid corrosives agents, and also radioactive substances. This research study mitotic activity in the roots of onion plants to determine the effects of soaking time of aceto orcein dye on actively dividing root cells. A series of several root tip from each bulb was harvested were soaked in 1, 3 and 24 hours on aceto-orcein stain and processed further for cytological studies by the aceto-orcein squash technique. The research was carried out to study the effect of to mitotic index and chromosomal aberration on onion root. It will determine the percentage of cells that are undergoing mitosis. The squash techniques were used to observe mitosis in the tip of onion root cells during actively mitotic division cells time. Mitotic divisions occur in several phases, consist of prophase, metaphase, anaphase, telophase and interphase. Experiment were repeated six times for every soaking time. The data was analyzed by using T-Test. The result showed that various duration of soaking time significantly influenced the reduction of mitotic index value. The lowest mitotic index on glyphosate concentration 100 ppm i.e. 10. 73% and 7.19% for the duration of soaking time 3 and 6 hours. The highest mitotic index on glyphosate concentration 0 ppm i.e. 37.71% and 32.76% for the duration of soaking time 3 and 6 hours. The result also showed that the chromosomal aberration were increased significantly. The lowest chromosomal aberration obtained i.e. 2.55% and 2.96% for the duration of aceto orcein soaking time 1, 3 and 24 hours. The highest chromosomal aberration obtained i.e. 21.71% and 36.26% for the duration of soaking time 1,3 and 24 hours. The type of chromosomal aberration were abnormal prophase, stickiness, bridge, abnormal anaphase, clumping chromosome, c- metaphase, change of nucleous shape and size. At 72h, their cytotoxic effects on the root tips showed strong growth retardation in high concentrations of all the wastewaters. Compared to the control, treatment with the wastewaters resulted in root growth inhibition with EC50 values of 35, 50 and 62% for bottling, rubber and brewery effluents respectively, and decrease in mitotic index with increasing concentration for all samples and these were statistically significant (p<0.05). Chromosomal aberrations induced in the onion root tip cells were mostly sticky chromosomes and bridges. Chromosomes with disturbed spindles and fragments were also present in appreciable amounts. Based on the EC50 values, the bottling wastewater was most toxic, followed by rubber effluent while effluents from the brewery were least toxic. The findings in this study indicate that there are toxic chemicals present in the wastewaters which are responsible for the observed genotoxic effects on the onion root tip cells. The study also reveals that the Allium test is a useful and reliable tool for the genotoxicity screening of industrial effluents which could be employed by environmental managers before these effluents are finally discharged into the environment. Key words: chromosomes, onion roots, acetoorcein

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Cytogenetic impact of sodium chloride stress on root cells of Vigna radiata L. seedlings

Turkish Journal of Biochemistry ◽

10.1515/tjb-2018-0352 ◽

2020 ◽

Vol 45 (2) ◽

Cited By ~ 1

Author(s):

Jabeen Farheen ◽

Simeen Mansoor

Keyword(s):

Mitotic Division ◽

Root Tip ◽

Ecological Problem ◽

Root Tips ◽

Root Cells ◽

Nacl Concentration ◽

Seedling Roots ◽

Metaphase Stage ◽

Tip Cells ◽

Root Tip Cells

AbstractObjectivesThe high salinization stress to seedling is the substantial ecological problem in the ongoing era. It negatively influences the growth that retard mitotic division by enhancing aberrations in nuclear chromatin. In the light of these views, the current work was designed to investigate the response of Vigna seedlings root tip cells to the presence of NaCl ions.Materials and methodsNM-92 and NM19-19 seeds were imbibed separately in distilled water for 24 h and allowed to grow into 0, 50, 150, 250, and 350 mM NaCl solution for 24 h. Excised root tips were stained, and slides were scored at 100× objective for the mitotic index (MI) and chromosomal aberrations.ResultsOur data demonstrated that as NaCl molarity increased, the MI was declined along with various chromatin abnormalities. The 150 mM of NaCl showed more lagging (69%) of chromosomes during anaphase in NM19-19. The highest stickiness at metaphase stage (68%) was found in 250 mM NaCl in variety NM19-19. However, both varieties were differed non-significantly for c-mitosis that was recorded 99% at 350 mM NaCl concentration.ConclusionsThe NaCl ions toxicity induced various cytological anomalies in seedling roots that adversely affect the growth of Vigna seedlings.

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Preprophase bands of microtubules and the cell cycle: Kinetics and experimental uncoupling of their formation from the nuclear cycle in onion root-tip cells

Planta ◽

10.1007/bf00634482 ◽

1988 ◽

Vol 174 (4) ◽

pp. 518-526 ◽

Cited By ~ 40

Author(s):

Y. Mineyuki ◽

S. M. Wick ◽

B. E. S. Gunning

Keyword(s):

Cell Cycle ◽

Root Tip ◽

Cell Cycle Kinetics ◽

Onion Root ◽

Nuclear Cycle ◽

Tip Cells ◽

Root Tip Cells ◽

Preprophase Bands

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Characterization of pharmaceuticals industrial effluent using GC–MS and FT-IR analyses and defining its toxicity

Applied Water Science ◽

10.1007/s13201-019-1064-z ◽

2019 ◽

Vol 9 (8) ◽

Cited By ~ 1

Author(s):

Vineeta Kumari ◽

A. K. Tripathi

Keyword(s):

Root Growth ◽

Mitotic Index ◽

Industrial Effluent ◽

Root Tip ◽

Chromosome Loss ◽

Chromosome Break ◽

Effluent Sample ◽

Effluent Concentration ◽

Tip Cells ◽

Root Tip Cells

Abstract The physicochemical analysis of collected effluent sample for different parameters shown results as pH (pH 5.6 ± 0.11) slightly acidic, high conductivity (1563.34 ± 176 μs cm−1), total dissolved solids (920.34 ± 137 mg L−1), high BOD (7253.34 ± 1022 mg L−1), and COD (756.67 ± 1124 mg L−1) in the effluent sample. The results of heavy metals concentration are viz. as [Cu (1.98–2.56), Co (0.26–0.53), Cd (0.10–0.50), Ni (0.04–0.07), Pb (0.58–1.2), Mn (0.58–1.05), Cr (1.47–1.51), Zn (2.61–3.5), Fe (1.72–2.13), As (0.05–0.09), and Hg (0.003–0.006)]. Results revealed the higher concentration of BOD, COD, TDS, and conductivity and also the concentration of lead. Results of GC–MS also confirmed the high levels of organic pollutants in effluent. Further the effluent toxicity was evaluated by employing genotoxocity assays with the use of Allium cepa L. (onion) root tip cells. Genotoxicity measured mitotic index (MI) and chromosomal aberrations (CAs) in root tip cells obtained after treatment with effluent of 6.25, 12.5, and 25% concentration (v/v). The results of root growth test showed that inhibition of root growth occurred at effluent concentration ≥ 50% (v/v). The lowest MI was recorded (MI = 9.6%) in 25% of effluent concentration, showing a significant reduction in mitotic index compared with control which MI = 64.1%. Further, the chromosomal aberration was investigated in root tip cell after treating with different concentration ranges of effluent exhibiting various CA, viz. c-mitosis, chromosome loss, chromosome break, micronucleated cells, etc. The result suggests that the effluent contained toxic constituents, which imposed cytotoxic and genotoxic hazard.

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Physiological responses and chromosomal aberration in root tip cells of Allium sativum L. to cerium treatments

Plant and Soil ◽

10.1007/s11104-016-2978-y ◽

2016 ◽

Vol 409 (1-2) ◽

pp. 447-458 ◽

Cited By ~ 6

Author(s):

Qiu-Man Xu ◽

Ya-Zhe Wang ◽

Hui Liu ◽

Jing-Sheng Cheng

Keyword(s):

Chromosomal Aberration ◽

Allium Sativum ◽

Physiological Responses ◽

Root Tip ◽

Tip Cells ◽

Root Tip Cells

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Pro-metaphase arrest, polyploidy, micronuclei, and mitotic abnormality inducing agents’ isolation from leaf aqueous extract of Clerodendrum viscosum Vent

10.1101/2020.11.29.402370 ◽

2020 ◽

Cited By ~ 1

Author(s):

Sujit Roy ◽

Lalit Mohan Kundu ◽

Gobinda Chandra Roy ◽

Manabendu Barman ◽

Sanjib Ray

Keyword(s):

Root Growth ◽

Petroleum Ether ◽

Aqueous Extract ◽

Root Tip ◽

Root Growth Inhibition ◽

Leaf Aqueous Extract ◽

Clerodane Diterpenoids ◽

Clerodendrum Viscosum ◽

Tip Cells ◽

Root Tip Cells

AbstractClerodendrum viscosum is a traditionally used medicinal plant and the earlier reports indicate its leaf aqueous extract (LAECV) contains metaphase arresting, cell cycle delay, and mitotic abnormality inducing active principles. The present study aimed to isolate pro-metaphase arresting, polyploidy, micronuclei, and mitotic abnormality inducing active principles of LAECV. The LAECV was successively fractionated as petroleum ether (PEF), chloroform (CHF), and ethyl acetate (EAF) fractions. All the extract fractions were tested for Allium cepa and Triticum aestivum root swelling and root growth inhibition analyses. The petroleum ether fraction was selected for further cytotoxicity analysis on A. cepa root tip cells and was processed for detection of the active principles through HPLC, LC-MS, GC-MS, and IR analyses. The comparative seedlings’ root growth and swelling patterns indicate the bioactive principles are effectively fractionated in PEF and GC-MS analysis revealed the presence of Clerodin (m/z 434.3), 15-hydroxy-14, 15-dihydroclerodin (m/z 452), 15-methoxy-14, 15-dihydroclerodin (m/z 466), and 14, 15-dihydroclerodin (m/z 436) with a retention time of 14.038, 14.103, 14.480 and 14.655 respectively. Thus the present study explores clerodane diterpenoids of LAECV as pro-metaphase arresting, polyploidy, micronuclei, and mitotic abnormality inducing active principles.

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INATE AND PHOTO-CONTROLLED MITOTIC RHYTHMS IN ONION ROOT-TIP CELLS

Canadian Journal of Genetics and Cytology ◽

10.1139/g73-079 ◽

1973 ◽

Vol 15 (4) ◽

pp. 667-670 ◽

Cited By ~ 1

Author(s):

Richard C. Bishop ◽

Richard M. Klein

Keyword(s):

Mitotic Activity ◽

Diurnal Rhythm ◽

Low Temperatures ◽

Root Tip ◽

Fluorescent Light ◽

Onion Root ◽

Seed Imbibition ◽

Tip Cells ◽

Root Tip Cells ◽

Red Radiation

A four-peaked diurnal rhythm in mitotic activity of dark-grown onion root-tip cells is initiated upon seed imbibition, damps rapidly and is lost within 5 days. It is abolished by continuous white fluorescent light, by continuous blue, green or red radiation, by low temperatures, high osmotica or anoxia. Photoperiodic light controls the well-known two-peaked persistent rhythm. The nature of the zeitgeber for either the inate or the photoperiodically-controlled rhythms is unknown.

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