Effect of Exogenous Calcium on Tolerance of Winter Wheat to Cold Stress during Stem Elongation Stage.

Low-temperature stress during stem elongation is a major factor limiting wheat yield. While calcium (Ca 2+ ) is known to enhance stress tolerance, it's potential as an alternative to cold priming and the underlying mechanisms in wheat remains unclear. The current study assessed the effects of exogenous Ca 2+ and calcium inhibitors on wheat growth and related physiology mechanisms under low-temperature stress. The results revealed that exogenous Ca 2+ increased photosynthesis and antioxidant capacity, lowered cell membrane damage, and ultimately enhanced tolerance to low-temperature stress during the stem elongation stage, compared with the non-exogenous Ca 2+ treatment. Moreover, exogenous Ca 2+ induced endogenous Ca 2+ content and triggered the upregulation of Ca 2+ signaling and cold-responsive related genes. This study highlights the significance of exogenous Ca 2+ in enhancing stress tolerance and contributing to wheat yield improvement under low-temperature stress.