Effects of long exposure to spent potliner on seeds, root tips, and meristematic cells of Allium cepa L.

Abstract

Spent potliner (SPL) is a solid waste generated in the aluminum mining and processing industry. It is sometimes dumped into the environment and leach in contact with water, thereupon affecting living beings, which are likely to be exposed to the waste for long periods. Considering this, we aimed to evaluate the effects of extended exposure to SPL through bioassays using Allium cepa as plant model system. Seeds of A. cepa were either directly exposed to SPL (continuous exposure) or first germinated in water and then exposed to SPL (discontinuous exposure). The germination rate was determined from 24 to 192 h of exposure. The maximum effects of SPL on germination were observed after 96 h in both exposure approaches. For the parameter root elongation, the discontinuous treatment was more efficient in demonstrating differences among the applied SPL concentrations (60% of reduction). Microscopic analysis was carried out in root tip cells discontinuously exposed to SPL for 96 h. A mitodepressive effect was observed (above 50%), as well as increased rate of chromosome abnormalities (up to 100-fold) and induction of cell death. The consequences of exposure to SPL for longer periods are discussed.

Efects of a S-Metolachlor Based Herbicide on Two Plant Models: Zea Mays L. And <i>Lactuca Sativa L.</i>

“…Agents that reduce mitotic index have a tendency to also increase the frequency of condensed nuclei [25,26]. This was observed in the current study where the presence of condensed nuclei was observed on the tested dosages of 30 and 60 mg L -1 .…”

“…Root length is a parameter that relates with the rate of cell division and the mitotic index indicates this rate of division [25]. On the present work this relation was very evident, during the cytogenetic analysis it was observed that the herbicide interfered on the mitotic index and that was expected once you consider that the active ingredient tested also provoked a reduction on root and shoot growth as well as on the seedling as a whole.…”

“…On the present work this relation was very evident, during the cytogenetic analysis it was observed that the herbicide interfered on the mitotic index and that was expected once you consider that the active ingredient tested also provoked a reduction on root and shoot growth as well as on the seedling as a whole. This happens because the increase in the number of cells is required for the development of any plant organ, and the mitotic index indicates the rate of cell division [25].…”

Environmentally realistic concentrations of eprinomectin induce phytotoxic and genotoxic effects in Allium cepa

“…Thus, a reduction in MI relative to the control indicates that differences are derived from the chemical effect of the substance, which results in the inhibition of the growth and development of the organism (Leme and Marin-Morales 2009 ). Mito-depressive effects have already been reported regarding the reduced elongation of A. cepa roots exposed to the herbicide imazethapyr (Liman et al 2015 ), metals (Gupta et al 2018 ), and mining waste (Andrade-Vieira et al, 2017 ).…”

Optimization of Spent Cathode Carbon Purification Process under Ultrasonic Action Using Taguchi Method

“…Untreated SCC causes pollution of surface water and groundwater when it be landfilled or piled up in the open air. SCC threatens the health of animal and plant seriously, and ecological balance. − As a worldwide concern about the environmental problem, spent cathode carbon has been classified as a hazardous solid waste in many countries and there are particular requirements in SCC treatment, storage, and transportation.…”