Halophyte anti-oxidant feedback seasonality in two salt marshes with different degrees of metal contamination: search for an efficient biomarker

Abstract

Salt marshes can be affected by metal contamination when near a polluted area, and this excessive concentration of metals is a source of stress in plants. Production of proteins, flavonoids, phenolic compounds and anti-oxidant feedback can be used as biomarkers, as well to assess the suitability of halophytes to function as a biomonitors. Through monitoring the anti-oxidative feedback in Halimione portulacoides (L.) Aellen, Sarcocornia fruticosa (L.) A.J.Scott and Spartina maritima (Curtis) Fernald in a contaminated and non-contaminated marsh, S. maritima seems to have potential as a bioindicator species, showing different biochemical characteristics according to the degree of contamination to which it is exposed. The evident biochemical separation between individuals from contaminated and non-contaminated salt marshes is mostly due to differences in the activity of SOD as well APx and GPx. Without neglecting the need for further works, the present study suggests that S. maritima enzymatic defences as good candidates for efficient biomarkers for estuarine sediment quality assessment studies.

Functional and ecophysiological traits of Halimione portulacoides and Sarcocornia perennis ecotypes in Mediterranean salt marshes under different tidal exposures

“…As a consequence, salt marshes are characterized by low floristic diversity and composed by species occurring in distinct vegetation areas (Woerner and Hackney 1997). Several works have focused on the influence of salinity, tidal submersion, and nutrient levels on salt marsh physiology and zonation (Rogel et al 2000;Duarte et al 2013aDuarte et al , 2014aCac¸ador and Duarte 2014), but few have explored these aspects in natural conditions, using systems with different tidal exposures regimes and their effects as ecotypes generators. At the basis of these diversity differences, are physiological effects imposed by abiotic changes promoted by inundation, with more evident effects in the plant primary metabolism, due to for e.g.…”

Biophysical and Biochemical Markers of Metal/Metalloid-Impacts in Salt Marsh Halophytes and Their Implications

“…These species were biochemically separated and also differed in the activity of SOD as well APX and GOPX. However, exhibition of a degree of contaminationdependent differential biochemical characteristics (especially enzymatic defense) was argued a basis of "bioindicator" role of S. maritima for estuarine sediment quality assessment studies (Duarte et al, 2013b). Specific peroxidases (such as APX and GOPX) were reported as a marker of contamination in salt marsh, where these peroxidases were involved in Cd-driven ROS detoxification in H. portulacoides, S. fruticosa, and S. maritima (Duarte et al, 2013b).…”

“…Antioxidative feedback was monitored in a number of salt marsh plants including H. portulacoides, Sarcocornia fruticosa, and Spartina maritima in a contaminated and non-contaminated marsh (Duarte et al, 2013b). These species were biochemically separated and also differed in the activity of SOD as well APX and GOPX.…”

“…However, exhibition of a degree of contaminationdependent differential biochemical characteristics (especially enzymatic defense) was argued a basis of "bioindicator" role of S. maritima for estuarine sediment quality assessment studies (Duarte et al, 2013b). Specific peroxidases (such as APX and GOPX) were reported as a marker of contamination in salt marsh, where these peroxidases were involved in Cd-driven ROS detoxification in H. portulacoides, S. fruticosa, and S. maritima (Duarte et al, 2013b). Elevated activity of SOD, that yields H 2 O 2 production was argued to produce stimulatory effect on APX in Zn-hyperacumulating J. acutus , and on GPX in the same plant under Cd stress .…”

“…The concept of this figure is based on Santos et al (2014). enlightening plant health under stressful conditions (Gill and Tuteja, 2010;Anjum et al, 2012a,b;Duarte et al, 2013b). Notably, a simultaneous presence of both oxidized and reduced forms of electron carriers is essential for the efficient flux through plant electron transport cascades that in turn contributes to the generation of superoxide and other ROS (Foyer and Noctor, 2005).…”