Zn2+-induced changes at the root level account for the increased tolerance of acclimated tobacco plants

Abstract

SummaryExposing plants to non-toxic metal concentrations elicits specific detoxification mechanisms in tobacco roots that improve root membrane functionality and leaf stomatal regulation with toxic zinc in the growing medium.

Awaiting better times: A quiescence response and adventitious root primordia formation prolong survival under cadmium stress in Tetradenia riparia (Hochst.) Codd

“…S2b), these results support the view that photosynthesis was initially limited by CO 2 diffusion as a consequence of low leaf stomatal conductance ( Medrano et al, 2002). This result is in accordance with the increasing evidence suggesting that exposure to toxic metal concentrations initially affects plant water relations (Barcelo and Poschenrieder, 1990;Sagardoy et al, 2010;Bazihizina et al, 2014).…”

Water relations in plants subjected to heavy metal stresses

“…It has been found that the leaf area decreased in P. vulgaris exposed to Cd (Barceló et al 1986a(Barceló et al , 1988, C. sativus treated with Cu (Vinit-Dunand et al 2002) and Nicotiana tabacum subjected to an excess of Zn (Bazihizina et al 2014). In P. Fig.…”

“…If soils are high in soluble salts (including heavy metal salts), the osmotic potential in the soil solution might be lower than the potential of the cell sap in root. Under these circumstances, the soil solution would severely restrict the rate of water uptake by plants Barceló et al (1986a) Leaf Phaseolus vulgaris Becerril et al (1989) Leaf Medicago sativa Becerril et al (1989) Leaf Triforium pratense Poschenrieder et al (1989) Leaf Helianthus annuus Kastori et al (1992) Root, shoot Oryza sativa Moya et al (1993) Shoot Lactuca sativa Costa and Morel (1994) Shoot Lupinus albus Costa and Morel (1994) Shoot Pisum sativum Hernández et al (1997) Leaf Silene vulgaris Schat et al (1997) Leaf Hordeum vulgare Vassilev et al (1997Vassilev et al ( , 1998 Kholodova et al (2005Kholodova et al ( , 2011 Root Nicotiana tabacum Bazihizina et al (2014) Root, shoot Beta vulgaris Sagardoy et al (2010) Mesembr. cryst.…”

“…Studies on B. vulgaris exposed to Zn indicated that xylem ABA concentration was reduced (Sagardoy et al 2010). Anatomical analyses revealed that Zn and Ni at high concentrations caused severe damage in the roots of N. tabacum and P. guajava (Bazihizina et al 2014(Bazihizina et al , 2015 and Zn affected the functionality of the root plasma membrane (Bazihizina et al 2014). It can be supposed that enhanced metal concentrations could have a detrimental effect on ABA synthesis in roots (Sagardoy et al 2010).…”

Got to hide your Zn away: Molecular control of Zn accumulation and biotechnological applications

“…A. halleri plants grown hydroponically accumulate metal ions in the cell wall of the rhizodermis mainly as Zn/Cd phosphate precipitates [95]. Excessive concentrations of metals have negative and even toxic effects on the plasma membrane of root cells, expressed as disturbed membrane functionality, which causes changes in membrane potential (E M ) and increased plant water loss [96,97]. The effects of divalent metal cations such as Cd 2+ and Zn 2+ on E M differ mainly according to the available heavy metal concentration, to its affinity status and mode of action [97,98].…”