Analysis of benzotriazole influence on some morphological and physiological characteristics of <i>Allium fistulosum</i>

Abstract

The increase in anthropogenic pressure has led to the need for model experiments to assess the ability of organisms to adapt to xenobiotics. The study of negative effects is usually carried out in laboratories using animals as test objects, while it is more interesting to study tolerance and adaptive capabilities in plant organisms, because, unlike animals, they are not able to leave an area uncomfortable for existence. In order to obtain an objective response in experiments, it is necessary to choose test objects related to species that are ubiquitous in ecosystems, and xenobiotics that are widely used and able to enter the environment. Allium fistulosum L. was used in model experiments and was affected by benzotriazole to study the possibility of developing an adaptive response in plants to anthropogenic pollutants. Plants were preadapted to a toxic dose of benzotriazole at a concentration of 0,1 mg/ml, by exposure to alcohol solutions of benzotriazole at a concentration of 0,0001 mg/ml or 0,001 mg/ml, and the time of preliminary exposure varied from 1 day to 4 days, then test objects germinated in a solution of high concentration. There were three controls, where the seeds were germinated for five days in all three used concentrations of benzotriazole, as well as in a solvent, which was 0,5% isopropyl alcohol. The possibility of adaptive response was assessed using two morphophysiological indicators, these were the germination of seeds and the average root length on the fifth day of the experiment. Experiments have shown that a solution of benzotriazole at a concentration of 0,1 mg/ml inhibits seeds germination and roots growth compared with the control (germination in 0,5% isopropyl alcohol), while at a concentration of 0,0001 mg/ml it stimulates. Exposure to low concentrations reliably creates a preadaptation to the toxic dose, but the responses significantly differ in effectiveness depending on the duration of preadaptation and the concentration of the substance. The greatest effect on the toxic effect of benzotriazole is created by preadaptation in low concentrations over 3 days. Possible preadaptation mechanisms are discussed.