Cold hardiness of olive (Olea europaeaL.) cultivars in cold-acclimated and non-acclimated stages: seasonal alteration of soluble sugars and phospholipids

Abstract

SUMMARYIn many plant species, several physiological and biochemical changes occur during low-temperature-induced cold acclimation. A previous study with olive cultivars (Cansevet al.2009) demonstrated a correlation between the level of accumulation of certain leaf proteins besides antioxidative enzyme activities and cold hardiness of the cultivars. The present paper analysed soluble sugar (SS) and phospholipid (PL) contents of cold-acclimated (CA) and non-acclimated (NA) leaf tissues in order to explain the mechanism of cultivar-dependent response to cold in olive. In general, cold acclimation significantly increased total soluble sugar (TSS), reducing sugars and sucrose contents of all cultivars to various extents depending on the cold hardiness of cultivars. In addition, TSS, reducing sugars and sucrose contents in cold-tolerant cultivars were significantly increased, whereas TSS, reducing sugars and sucrose contents in cold-sensitive cultivars either did not change or increased slightly in CA stage compared with those in NA stage. Even though reducing sugars were the major soluble sugar in olive leaves, levels of sucrose accumulations in CA stage compared with those in NA stage were greater than those observed in reducing sugars accumulation. Changes in levels of total PL, as well as the three individual PL fractions phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylinositol (PI), were investigated in olive leaf tissues. Significant increases in levels of PC and PE fractions during CA compared with those in NA stage suggested that PC and PE maintained the cold hardiness of olive cultivars more effectively than did PI. Although the precise mechanisms by which olive responds to cold may still be open to discussion, soluble sugars and PL are clearly important in the ability of olive cultivars to stand against cold stress.

Freezing avoidance by supercooling inOlea europaeacultivars: the role of apoplastic water, solute content and cell wall rigidity

“…Furthermore, changes in phospholipids composition in plasmatic membrane contribute to tissue rigidity during cold acclimatation (Griffith & Brown ; Larcher ; Gulen et al . ).…”

“…Enhanced pectin synthesis has been observed in the cell walls of other species during cold acclimation (Kubacka-Zebalska & Kacperska 1999;Baldwin et al 2014) which contributes to lower porosity of the cell wall and possibly to increase ε. Furthermore, changes in phospholipids composition in plasmatic membrane contribute to tissue rigidity during cold acclimatation (Griffith & Brown 1982;Larcher 1982;Gulen et al 2009).…”

The Role of Hydrogen Peroxide in Mediating the Mechanical Wounding-Induced Freezing Tolerance in Wheat

“…The Pn, Gs, and Tr were reduced, but the Ci was increased after the application of DPI or DMTU, hinting a possibility that H 2 O 2 is involved in wounding induced photoinhibition. Freezing responses are associated with the changes in antioxidant system ( Gulen et al, 2009 ; Zhou et al, 2012 ). Consistent with earlier studies, we found that the activities of antioxidant enzymes, such as SOD, CAT, APX, and GR, were increased after wounding and freezing treatment.…”

Olive (Olea europaea L.) freezing tolerance related to antioxidant enzymes activity during cold acclimation and non acclimation

“…Previous studies also showed that there is a correlation between some physiological and biochemical characteristics such as stomatal density (Roselli et al 1989), stomatal size (Roselli and Venora 1990), phenolic compounds (Roselli et al 1992), differential thermal analysis (Martin et al 1993), ionic leakage Azzarello et al 2009), fractal analysis (Azzarello et al 2009), impedance spectroscopy (Azzarello et al 2009), soluble sugars Bartolozzi et al 2001;Gulen et al 2009) and total soluble proteins (Eris et al 2007;Cansev et al 2009) with frost-tolerant in olive genotypes. Currently, interesting results to quantify cold tolerance have come from the study of some antioxidant enzymes (Solecka and Kacperska 2003;Cansev et al 2009;Ortega-García and Peragón 2009).…”