Biomarker Responses of Spanish Moss Tillandsia usneoides to Atmospheric Hg and Hormesis in This Species

Abstract

Hg is an environmental pollutant with severe biotoxicity. Epiphytic Tillandsia species, especially Spanish moss T. usneoides, are widely used as the bioindicator of Hg pollution. However, the effects of different Hg concentrations on Tillandsia have been rarely studied and the occurrence of hormesis in Tillandsia species has not been determined. In this study, T. usneoides was subjected to stress induced by 15 concentrations of gaseous Hg ranging from 0 to 1.8 μg m–3 through a misting system and then Hg content and eight common biomarkers in leaves were measured. The results showed that leaf Hg content significantly increased with Hg concentration, showing a linear relationship. However, there were no obvious mortality symptoms, indicating that T. usneoides showed strong resistance to Hg. Conversely, there were no simple linear relationships between changes in various biomarkers following Hg treatment of T. usneoides and Hg concentration. With increasing Hg concentration, malondialdehyde (MDA) content did not change significantly, superoxide anion radical content decreased gradually, superoxide dismutase (SOD) content decreased to the bottom and then bounced back, electrical conductivity increased, and glutathione (GSH) and metallothionein (MT) content increased to the peak and then dropped. The coefficient of determination of the dose-effect curves between SOD, GSH, and MT contents and Hg concentration was high, and the dose-effect relationship varied with hormesis. The present study is first to confirm hormesis induced by heavy metal pollution in Tillandsia species.

Eustress and Plants: A Synthesis with Prospects for Cannabis sativa Cultivation

“…Another species of Tillandsia, T. usneoides, showed a predominant biphasic hormetic response at 10 different atmospheric lead-Pb concentrations; the hormetic response was confirmed by the levels of malondialdehyde (MDA) and superoxide anion radical and the superoxide dismutase (SOD) activity after 6-12 h, as well as by GSH and metallothionein-MT content after 12 h [27]. SOD, GSH, and MT also showed a hormetic response in T. usneoides exposed to different mercury-Hg atmospheric concentrations [28].…”

Identification of Ornamental Plants Via Google Lens Based on Intersemiotic

“…It is also a microhabitat that is a shelter for various organisms including one species of jumping spider, various species of bats and also rat snakes. In Schreck et al (2019) and Sun et al (2021) stated that the ornamental plant has an effective function as a bioindicator of metallic contamination and an indicator of atmospheric contamination. In, Rini et al (2008) and Rindita et al (2015), atmospheric contamination can occur due to air pollution caused by vehicles which are the main source of producing carbon dioxide, nitrogen oxides and sulfur oxides.…”

Air Quality Monitoring in the State of Rio De Janeiro, Brazil, Through Pollution and Ecotoxicological Biomonitoring Assessments

“…The MDA content at MRC was lower than MRRJ. In one study, T. usneoides was more resistant to membrane damage than A. fasciata (Giampaoli et al, 2021), while the aforementioned Hg exposure study revealed no significant difference in MDA concentrations with increasing Hg, indicating T. usneoides resistance to this metal (Sun et al, 2021a).…”

“…Moss, lichens and epiphyte plants are mostly employed for this purpose, as they obtain nutrients from the air by gaseous changes that occurs in their stomates and/or trichomes (Alves et al, 2008;Gioda et al, 2021;Zheng et al, 2017). Tillandsia species are excellent biomonitors in this context, obtaining their nutrients from the atmosphere and exhibiting high absorptive capacity (Sun et al, 2021a). Furthermore, as they are widely distributed in tropical areas, Tillandsia species are often chosen for atmospheric biomonitoring efforts in South America De La Cruz et al, 2021;Gioda et al, 2021;Piazzetta et al, 2019).…”