Contrastive responses of spring and winter wheat cultivars to chilling and acclimation treatments

Abstract

Photosynthesis and antioxidant defense system were investigated under chilling stress without (Ch, and with acclimation (AcCh, 14-4 ºC) in winter (Sabalan) and spring (Zagros) wheat (Triticum aestivum L.) cultivars. Maximum quantum efficiency of photosystem II and CO 2 assimilation rate decreased in AcCh 'Zagros' but not in 'Sabalan', and in contrast, an increase in non-photochemical quenching was observed in 'Sabalan' but not in 'Zagros'. Reduction of leaf starch content was observed in both cultivars while total soluble carbohydrates increased only in 'Sabalan' under both Ch and AcCh treatments. Activity of superoxide dismutase was significantly higher in Ch plants and activity of ascorbate peroxidase and catalase was slightly higher in Ch and AcCh plants of both cultivars compared with control. Activity of peroxidase increased in Ch and AcCh plants of 'Zagros' while phenylalanine ammoialyase (PAL) activity increased in AcCh 'Sabalan'. Increase in the leaf content of H 2 O 2 and malondialdehyde (MDA) was more prominent in 'Zagros' than in 'Sabalan'. According to our results, chilling tolerance in winter cultivar was associated with greater thermal dissipation, higher soluble carbohydrates content, greater PAL activity and lower H 2 O 2 and MDA content. Furthermore, acclimated plants were not more protected against chilling injury compared with non-acclimated ones.

Perspective Chapter: Effect of Low-Temperature Stress on Plant Performance and Adaptation to Temperature Change

“…Various studies showed a similar response to cold stress in wheat [61], strawberries [62], and barley [63]. Hajiboland and Habibi [64] reported that in cold-treated seedlings, the activity of SOD increased significantly, while in the acclimated seedlings, SOD activity did not differ from the control.…”

“…Higher POD and SOD activity probably suggest their possible role in mitigating adverse environmental damage. Hajiboland and Habibi [64] reported a slight increase in CAT activity in both wheat cultivars under chilling temperatures with and without acclimation. In contrast, POD activity increased in spring wheat cultivar but not in winter wheat by both temperature treatments.…”

“…In chilling stressed petunia leaves, it was observed that stress led to elevated antioxidant capacity and total phenolic content [94]. Hajiboland and Habibi [64] reported that PAL activity was increased in winter wheat cultivars under acclimation and more phenolic content accumulated in seedling leaves. The transcription level of PAL and phenolic content was higher in acclimated chickpea seedlings than in non-acclimated ones [37].…”

Changes of Enzymatic Antioxidants and Minerals Content of Broad Bean ( Vicia faba L.) Plants in Response to Chilling Stress and Reacclimation

“…In this connection, many authors have been reported that low temperature stimulated the scavenging of H 2 O 2 by both enzymatic antioxidants CAT and APx (Hajiboland & Habibi, 2011;Mohammadian et al, 2012;Sorour, 2014). In contrast, Kang & Saltveit (2001) and Ping et al (2012) have reported that chilling stress resulted in a significant decrease of CAT activity in cucumber seedlings and rubber colenes respectively, while, Galli et al (2009) showed that APx activity did not show a clear trend during the cold storage of pawpaw fruits.…”

“…Under heat stress, plants contain numerous enzymatic ROSscavengers antioxidants, including superoxide dismutase (SOD), catalase (CAT), peroxidase (POx), ascorbate peroxidase (APx), glutathione peroxidase (GPx) and glutathione reductase (GR) as well as non enzymatic antioxidants such as ascorbate, glutathione and phenolics (Kang & It has been reported that chilling stress enhanced SOD activity in several plants including cucumber (Kang & Saltveit, 2002), wheat (Hajiboland & Habibi, 2011) and citrus fruit (Mohammadian et al, 2012). reported that CAT activity significantly increased during chilling stress, while Ping et al (2012) reported a decrease of CAT activity in rubber tree clones seedlings in response to chilling stress.…”