Antioxidant enzyme activities in Allium species and their cultivars under water stress

Abstract

We compared the enzymatic antioxidative defence mechanisms of some regional subspecies of Allium (A. cepa L., A. ascalonicum auct. hort., A. sativum L.) cultivated mainly in the western regions of Romania, and two modern Hungarian climate resistant F 1 hybrids. The variability in the activities of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), glutathione reductase (GR) and glutathione S-transferase (GST) and their changes under soil moisture stress were investigated. 1-week-long water stress revealed that among three Allium species, relative water content decreased only in A. ascalonicum leaves (up to 16%). Unlike root enzymes, the activities of the shoot enzymes, especially POD, GR and GST showed a stronger correlation with the water content of the leaves after one week of water withdrawal; regression coefficients (R 2 ) were 0.359, 0.518 and 0.279, respectively. The ancient populations with elevated (or highly inducible) antioxidant enzyme activities may be interesting for further research and for breeding of new Allium varieties.

Antioxidant and other biochemical defense responses of Macrotyloma uniflorum (Lam.) Verdc. (Horse gram) induced by high temperature and salt stress

“…Levels of SOD are also correlated with NaCl tolerance, probably due to effective scavenging of O 2 . Results with high temperature and 600 mM NaCl stress in horse gram are in agreement with those reported for Cassia angustifolia (Agarwal and Pandey, 2004) and salt tolerant cultivars of Allium species (Csiszar et al, 2007). However, our results are in contrast with salt stressed Catharanthus roseus (Jaleel et al, 2007), potato (Rahnama and Ebrahimzadeh, 2005) and wheat seedlings which showed a initial increase at 50 mM NaCl and subsequent decline with increasing concentration of salt (Esfandiari et al, 2007).…”

“…Increased GR activity in leaves of sugar beet plant has been closely related with salt tolerance capacity (Bor et al, 2003). Elevated levels of GR under temperature stress in horse gram coincide with drought stressed Arabidopsis (Jung, 2004) and water stressed Allium species (Csiszar et al, 2007).Considering the common effect of dehydration by high temperature and salt stress, higher levels of GR could be related to high temperature tolerance in horse gram. Reduction of GR in horse gram stressed with salt is similar to salt stressed wheat seedlings (Esfandiari et al, 2007).…”

Over-expression of TaEXPB23, a wheat expansin gene, improves oxidative stress tolerance in transgenic tobacco plants

“…In general, class III peroxidases are secreted into the cell wall or the surrounding medium, where they are the key players during the entire plant life cycle, particularly in cell wall modifications (Passardi et al, 2004). The involvement of peroxidases in physiological and developmental processes has been detected in some plants (Csiszar et al, 2007;Maxwell and Johnson, 2000). One feature of these peroxidases is that they are associated with cell elongation and with reactions that restrict growth (Csiszár et al, 2011).…”

Purification and characterization of a peroxidase present in xilopodium exsudates of umbu plants (Spondias tuberosa A.)

“…Plants that exhibit comparably high resistance to climatic stress have been shown to possess relatively higher enzymatic antioxidants levels, such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and GPX (guaiacol peroxidase) than susceptible varieties. S. tuberosa, despite being a dry resistant tree, has not been yet investigated in this sense, and no information about enzymes related to this property is available currently (Csiszár et al, 2007). Peroxidases are present in several organisms from many species including bacteria, fungi and animals (Hiraga et al, 2001).…”