ECOPHYSIOLOGICAL AND BIOCHEMICAL PARAMETERS FOR ASSESSING Cr+6 STRESS CONDITIONS IN Pterogyne nitens Tul.: NEW AND USUAL METHODS FOR THE MANAGEMENT AND RESTORATION OF DEGRADED AREAS

Abstract

Heavy metals, such as Cr (chromium), have received attention during recent years due to their disposal in soil and water. Brave peanut (Pterogyne nitens Tul.), a tropical tree, was cultivated in 500 mol L -1 Cr +6 to observe how this species responds to this stress, with a view to its possible application in the restoration of degraded areas. In the present study, we report the use of a new method, photoacoustic spectroscopy, to evaluate the emission of CO 2 and ethylene and the use of other standard techniques for assessing stress (chlorophyll a fluorescence, photosynthetic pigment determination, leaf relative water, specific leaf area, NO (nitric oxide) and polyamines. Photoacoustic spectroscopy appears to provide an innovative and efficient technique for detecting stress induced by heavy metals soon after their contact with plants. Polyamine content, as well as ethylene and NO, were seen to be sensitive to Cr +6 ; polyamines were decreased in leaves and increased in roots, ethylene was increased in the whole plant and NO was increased in the roots. Our results demonstrating alterations in ethylene in response to Cr +6 are, to date, unreported and the technique used for these measurements is novel. With regard to the polyamines, modulations in their concentrations may have protected the photosystem II, since no photosynthetic alterations were observed for pigments and chlorophyll a fluorescence.

Chromium Bioaccumulation and Its Impacts on Plants: An Overview

“…Oryza sativa Increased ethylene synthesis Trinh et al [33] Oryza sativa Increased CAT and SOD activities Zhang et al [34] Oryza sativa Increased POD activity Xu et al [35] Phaseolus vulgaris Decreased carotenoids Aldoobie and Beltagi [36] Pisum sativum Decreased APX activity Duhan [37] Pterogyne nitens Increased spermidine level Paiva et al [38] Raphanus sativus Increased glycine-betaine content Choudhary et al [39] Triticum aestivum Increased MDA contents Ali et al [22] Triticum aestivum Increased lipid peroxidation Zhang et al [34] Vigna radiata Decreased glutathione level Shanker et al [40] Zea mays Increased SOD and GPX activities Maiti et al [41] Zea mays Increased lipid peroxidation and H 2 O 2 content Maiti et al [41] Abbreviations: Malondialdehyde-MDA; Superoxide dismutase-SOD; Catalase-CAT; Ascorbate peroxidase-APX; Peroxidase-POD; Guaiacol peroxidase-GPX; Hydrogen peroxide-H 2 O 2.…”

“…Polyamines are other non-enzymatic osmoprotectants, which increase under different abiotic stress conditions [151], and also associated with the boosting up of plant defensive mechanisms [92,152]. Polyamines including putrescine, spermine and spermidine have been investigated to increase Cr tolerance in plants under Cr toxicity [38].…”

Possible remediation of hexavalent chromium by native fungi of Sukinda mining area: a review

“…With increase concentration of chromium symptoms of chlorosis and necrosis is progressively visible with a sharp decline in protein production and nitrogenase activity. (Paiva et al,2014) Also reduced shoot and root growth with wilted leaves observed at early stage (Rai et al, 2014). The morphological parameters severely affected by the application of chromium correspondingly the yield and production is also affected that may lead to no harvest condition.…”