Apoplastic and total peroxidase activities in Scots pine needles at subarctic polluted sites

Abstract

A gradient survey was carried out in order to compare peroxidase activity in Scots pine (Pinus sylvestris) needles in relation to distance from the industrial centre of Monchegorsk, on the Kola Peninsula in north-western Russia. Apoplastic and total peroxidase activity and sulphur (S), nickel (Ni) and copper (Cu) content in the needles of mature trees were measured on seven plots located between 10 and 110 km from the pollution source. Peroxidase activities in both current-and previous-year needles increased towards the smelters and showed a positive correlation with needle S, Cu and Ni concentrations. Total peroxidase activities showed a more obvious relationship to the pollution gradient in winter than in autumn. The element contents in the current year needles averaged 1649 ppm (S), 128 ppm (Ni) and 118 ppm (Cu) close to the smelters, 1212 ppm (S), 37 ppm (Ni) and 67 ppm (Cu) at a distance of 40 km and 831 ppm (S), 7 ppm (Ni) and 1 ppm (Cu) at the most distant sampling plot.This study showed that both the apoplastic and total peroxidase activities responded to heavy metal and sulphur pollution up to 40 km from the smelters in winter, which indicated an increased oxidative stress in this area. The harsh climate conditions and the high pollution levels may have had additive effects. However, as peroxidases are considered a general indicator of stress, it is not possible to evaluate the extent to which single pollutants contribute to this enzyme activity.

Peroxidase and Superoxide Dismutase Activities in Fig Leaves in Response to Ambient Air Pollution in a Subtropical City

“…Calzada et al (2001) showed that the peroxidase activity of Pinus radiata was generally higher in June than in September in a rural-forested area of northern Spain. At subarctic polluted sites, total peroxidase activity of Pinus sylvestris from an industrial center of Monchegorsk in northwestern Russia showed a clear relationship to the pollution gradient in winter compared to autumn (Roitto et al 1999). However, peroxidase activities of Ficus microcarpa did not show any significantly seasonal variation in the present study, whereas superoxide dismutase activities of Ficus microcarpa were usually the lowest during winter.…”

“…In fact, high peroxidase activity observed in this study cannot be attributed to ozone pollution alone in each study site. Several researchers have suggested that peroxidase activity may not be used as a specific indicator of single air pollutant and can only be considered as a general indicator of oxidative stress (Nyman 1986;Roitto et al 1999). Moreover, oxidation products generated from free radial reactions, such as aldehydes, have been suggested as useful biomarkers of O 3 exposure (Pryor et al 1996) or NO 2 exposure (Robison et al 1996).…”

Urban forest regeneration: Responses of Scots pine seedlings to partial humus removal in mid-boreal N-enriched forests

“…To obtain specific POD activity per protein content, the standard Bicinchoninic Acid assay (Roitto, Ahonen-Jonnarth, Lamppu, & Huttunen, 1999) was used for protein determination with bovine serum albumin as a standard.…”