Relationship between Freezing Tolerance and Leaf Growth during Acclimation in Winter Wheat

Abstract

Winter hardiness is influenced by many environmental factors, and freezing tolerance is among the main ones, rendering the phenotypic selection of winter wheat (Triticum aestivum L.) under field conditions a difficult task due to the irregular occurrence or absence of winter damage in field trials. Plant growth in response to low temperatures during the acclimation period might be used as an indirect approach to assess freezing tolerance. Thirteen winter wheat cultivars were investigated for autumn and spring growth and winter hardiness under field conditions for two growing seasons. Additionally, a precise and non-destructive technique was applied to study leaf growth at a high temporal resolution accompanied by a freezing tolerance test under laboratory and semi-field conditions. The results of the study revealed variations in thermal growth patterns among the 13 winter wheat cultivars. The cultivars with the lower base temperature (Tb) values, in particular ‘Lakaja DS’ and ‘Sedula DS’, grew slower and, thus, had a lower response to temperature increases (SlpLER-T) than the fast-growing cultivars, such as ‘Simano” and ‘KWS Ferrum’, whose SlpLER-T values were stronger and whose Tb values were higher. A correlation analysis of the investigated traits showed a clear association between leaf growth parameters and freezing tolerance, indicating a certain level of genetic adaptation to growth cessation under low temperatures, and which confirmed that these are important factors for explaining the freezing tolerance of different cultivars. The evaluated freezing tolerance (LT30) showed a strong negative correlation (r = −0.82 ÷ −0.89, p = 0.01) to winter hardiness scores from the field experiment, supporting the essential contribution of growth rate patterns to winter hardiness. The findings provide novel information for the development of winter-hardy wheat cultivars that are adapted to the future environments.

The effect of cold acclimation, deacclimation and reacclimation on metabolite profiles and freezing tolerance in winter wheat

“…Plant material, experimental design, and growth conditions Six winter wheat varieties ("Hanswin"-Switzerland; "KWS Ferrum, " "Nordkap"-Germany; "SW Magnifik"-Sweden; "Lakaja DS, " "Sedula DS"-Lithuania) with different winter hardiness profiles under Lithuanian climate conditions (presented in order from lowest to highest) were selected (Jaškūnė et al, 2022). Seeds were imbibed on moist filter paper in Petri dishes and kept in the dark for 4 days at 4 • C to stratify, and then transferred to room temperature for 16 h. A total of 216 seeds of each genotype were then sown in peat moss substrate (Durpeta, Lithuania) in 125 cm 3 28-well trays in a randomized pattern and grown in a greenhouse at 18 • C temperature and 12 h photoperiod until the three-leaf stage was reached.…”

“…Throughout CA, the growth of winter wheat is reduced, and numerous changes in transcriptome and metabolome are induced ( Zhao Y. et al, 2019 ; Aleliūnas et al, 2020 ). Moreover, low autumn temperatures lead to various physiological changes, such as reduced shoot biomass growth and leaf elongation rate, and decreased tissue water content ( Dalmannsdottir et al, 2017 ; Rys et al, 2020 ; Jaškūnė et al, 2022 ). Currently, the most documented conserved molecular signaling pathway, activated by CA, is the ICE-CBF-COR pathway.…”

The Application of Auxin-like Compounds Promotes Cold Acclimation in the Oilseed Rape Plant

“…The protein composition and the possible value of the condition of phytohormones and their physiological activity for the property of plant cold acclimation was highlighted in these experiments [ 28 , 29 ]. To summarize, natural habitat plants acclimate completely, while crops, especially those originating from warmer climatic zones, separate species, or even their individual cultivars, do not often successfully overwinter [ 29 , 30 ]. There is no straight answer to what determines the plant property for preparing properly for cold acclimation and its resistance to adverse environmental factors [ 30 , 31 ].…”

“…To summarize, natural habitat plants acclimate completely, while crops, especially those originating from warmer climatic zones, separate species, or even their individual cultivars, do not often successfully overwinter [ 29 , 30 ]. There is no straight answer to what determines the plant property for preparing properly for cold acclimation and its resistance to adverse environmental factors [ 30 , 31 ].…”

“…In the recent study, it was shown that plant adaptability and cold acclimation is one of the most important physiological, biochemical, and biotechnological problems for plants. Moreover, the detection of metabolic processes that are responsible for the mechanisms of resistance/adaptability in plants remains important, along with experiments on their wintering improvement with biotechnology tools [ 30 , 33 , 34 , 35 , 36 , 37 , 38 ]. Physiological-biochemical peculiarities of plant cold acclimation-preparation for wintering under natural conditions, including protein composition and especially changes in the amount and the status of the hormonal-regulatory systems of the phytohormone IAA under exogenous auxin-like compounds, have not been investigated or disclosed to date.…”