Influence of climatic conditions on the mutations in pollen mother cells of Tradescantia clone 4430 and implications for the Trad-MCN bioassay protocol

Abstract

The present study was aimed at investigating the influence of relative humidity and temperature on spontaneous and pollution-induced mutation rates during exposure and recovery periods in the Trad-MCN test. Cuttings of Tradescantia clone 4430 were exposed to a negative control, to 4 mM maleic hydrazide (MH), and to a polluted water sample under varying conditions of air temperature and humidity in climatic chamber experiments. The relative humidity did not affect the spontaneous mutation rate in the clone investigated, but was negatively correlated with the frequency of pollution-induced mutations. Low temperature caused an increase in the number of micronuclei in the negative control, but no comparable response in polluted samples. At an extremely high temperature, signs of strong physiological damage and/or of a meiotic delay of pollen maturation were detected. When the temperature increased gradually and the extreme value was maintained only for short time, such detrimental effects were not observed. Subsequent treatment with high and low temperatures, by contrast, resulted in the highest MCN rates of all experiments. Our studies point to the possibility of producing irregular results of the Trad-MCN test if the influence of climatic factors has not sufficiently been considered.

Cashew nut roasting: Chemical characterization of particulate matter and genotocixity analysis

“…The influence of weather conditions such as relative humidity, temperature and rainfall on the Trad-MCN assay as a result of exposure to genotoxic agents has been investigated by a number of studies (Klumpp et al, 2004;Savóia et al, 2009;Sisenando et al, 2011;Pereira et al, 2013). Corroborating Savóia et al (2009) and Sisenando et al (2011), we also observed an inverse relationship between the rate of MN and rainfall (Table 3).…”

Biomonitoring the genotoxic potential of the air on Tradescantia pallida var. purpurea under climatic conditions in the Sinos River basin, Rio Grande do Sul, Brazil

“…However, in November 2012, the high temperature recorded in the urban environment of Taquara (mean of 34.3 °C) may have contributed to the increased MCN frequency. Temperature from 33 °C on under controlled conditions was reported as increasing spontaneous mutation rate of Tradescantia clone 4430 by Klumpp et al (2004). Air pollutants and stressful climatic conditions caused effects on the response of Tradescantia pallida var.…”

“…Frequencies obtained for negative controls remained below the background rate of up to 2.0 MCN/100 tetrads considered by Pereira et al (2013) as the result of spontaneous mutations that can occur naturally in the species, even when plants are grown in environments free from interference of any type of pollutant. In order to minimize any environmental interference before exposure, it is important that plants be allowed to adapt in controlled conditions (Ma et al, 1994;Klumpp et al, 2004). This procedure was employed in this study, following Cassanego et al (2014).…”

Avaliação de mutagenicidade e antimutagenicidade de diferentes frações de Pterogyne nitens (Leguminosae), utilizando ensaio de micronúcleo em Tradescantia pallida

“…O teste de micronúcleo em Tradescantia pallida (Trad-MCN) é um dos bioensaios mais usados para o rastreamento de efeitos mutagênicos (Klumpp et al, 2004) e recentemente também vem sendo usado para detecção de efeitos antimutagênicos (Flores et al, 2003). Ele é baseado na formação de micronúcleos resultantes da quebra de cromossomos em células mãe de grão de pólen (Klumpp et al, 2004, Valadares et al, 2007.…”

“…Ele é baseado na formação de micronúcleos resultantes da quebra de cromossomos em células mãe de grão de pólen (Klumpp et al, 2004, Valadares et al, 2007.…”