Does 2,4-dichlorophenoxyacetic acid (2,4-D) induce genotoxic effects in tissue cultured Allium roots?

Abstract

2,4-Dichlorophenoxyacetic acid (2,4-D) is a synthetic plant growth regulator that is highly toxic to most broad leaved plants and relatively nontoxic to monocotyledonous plants; is frequently used as weed killer. The study aimed to investigate cytogenetic effects of different concentrations of 2,4-D (0.67, 1.34, 2.01, 2.68, 3.35 and 4.02 mg/L) on Allium cepa bulblets' root tips treated for 24 and 48 h. The results showed six types of structural aberrations: C-mitosis, stickiness, laggards, bridges, fragments and multipolarity that varied numerically compared to control. It significantly affected mitotic index (MI) at 24 and 48 h treatment. In the Allium test, MI increased significantly at three lower concentrations (0.67, 1.34, 2.01 mg/L) after treatment with 2,4-D for 24 h and decreased significantly at higher concentration. Whereas, 2,4-D treatment for 48 h increased MI at all concentrations with significantly decreased MI at the highest concentration. The experiment was extended using comet test that did not reveal significant difference among treatments except for application of 4.02 mg/L 2,4-D for 48 h; where cell damages were verified by comet test. Rest of the concentrations for any duration of time were not damaging and toxic to cells. The results showed, visible mitodepressive action of 4.02 mg/L 2,4-D when treated for 48 h that had tendency to become toxic if the roots had been in touch with 2,4-D for a longer time.

Concentration- and time-dependent effects of strontium on Lens culinaris Medik.

“…Metals have a positive effect on plant growth until their concentration reaches a certain point (Tangahu et al 2011;Bhargava et al 2012;Çanli 2018;Sabovljević et al 2018), and they also change the structure of chromosomes inside the plant (Özdemir et al 2015; Çanli 2018). In several investigations, six types of alteration in chromosomes were named, viz., bridges, C-mitosis, fragments, laggards, multipolarity and stickiness (Kuchy et al 2016;Özkul et al 2016). Moreover, Utsunomiya et al (2002) described abnormalities such as chromosome segregation, absence of cytokinesis, cytomixis, cell fusion, irregular cell shape, chromosome bridges and genomic separation.…”

Plant regeneration from hypocotyls of black carrot via direct somatic embryogenesis and determination of its genetic stability by RAPD and iPBS methods

“…High auxin application used in the somatic embryogenesis method to obtain embryogenic cells that divide rapidly induces stress in plants and may lead to chromosome fragmentation or loss of chromosomes, and genomic modifications such as fraction or fusion, made easier by transposition events (Ozkul et al 2016). Therefore, the amount of 2,4-D applied to obtain somatic embryos and whether the duration of incubation caused any genotypic changes were investigated by the RAPD and iPBS methods.…”

Evaluation ofin vitrogenotoxic effects induced byin vitroanther culture conditions in sunflower

“…[56][57][58] Several researchers reported that 2,4-D has cytogenetic effects, including chromosome abnormalities in the meiosis of barley and Vicia faba and sister chromatid exchanges in cultured immature embryos of wheat species. 59 Özkul et al, 24 Plants produce oxine and cytokine in their own tissues. These hormones can reach high doses in plants by supplementing these plant growth regulators from outside in plant tissue culture studies.…”

“…There are many studies related to genotoxic effects of in vitro culture parameters especially plant growth regulators onto different plant species by many researchers. [22][23][24]7,[25][26] The Comet assay is one of the most commonly used in vitro and in vivo mutagenesis tests that analyze cell reaction to genotoxic agent and additionally a few biotic and abiotic stresses that prompt oxidative DNA damage. This assay is based on the quantification of denatured DNA fragments migrating out of the cell nucleus during electrophoresis and highly useful tool for measuring DNA damage in cells which is widely used in fields ranging from molecular epidemiology to genetic toxicology.…”

“…This assay is based on the quantification of denatured DNA fragments migrating out of the cell nucleus during electrophoresis and highly useful tool for measuring DNA damage in cells which is widely used in fields ranging from molecular epidemiology to genetic toxicology. 24,27 Comet assay is an important method that can be applied on fungi, algae, theoretically all higher plants, sea creatures, insects, vertebrates and humans, both in terms of following with environmental health and informing about the defense potentials of the target organisms and their future health status. [28][29][30][31] In this study, it was evaluated that the changes on genotoxicity and antioxidant enzyme activities total protein content derived from androgenic calli tissues with the effect of plant growth regulators, genotypes and pretreatments in sunflower.…”