Abstract Using mineral nutrients is recommended as a plan to alleviate or avoid spring frost damage to blossoms. The purpose of this study was to investigate the effects of potassium application on reducing or preventing spring frost damage of almond (Prunus dulcis Mill.) flowers. Treatments were four levels of K2SO4 (0, 1, 2, and 4%). The nutrition solutions were sprayed on trees in two times (bud swell stage and green tip stage) in 2018–2019. The spurs containing flower buds were collected during the full blooming phase. The spurs segments were exposed to three different freeze test temperatures (0, −2, and −4 °C), and some relevant physiochemical changes were evaluated. The application of K2SO4, especially 4% K2SO4, decreased freezing injury, electrolyte leakage percentage, hydrogen peroxide (H2O2), and malondialdehyde (MDA) concentrations of flowers after freezing tests compared with control. The nutrient treatments, especially 4% K2SO4, increased significantly the contents of soluble proteins, soluble carbohydrates, total phenolic compounds, and proline of flowers. The results of the present study could have implications for the use of potassium in freezing tolerance improvement of other temperate fruit trees grown in low temperatures regions.

中文翻译：

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钾肥提高杏仁花的抗冻性

摘要 建议使用矿质营养素作为减轻或避免春季霜冻对花朵的伤害的计划。本研究的目的是调查施钾对减少或预防杏仁 (Prunus dulcis Mill.) 花春季霜害的影响。处理是四种水平的 K2SO4（0、1、2 和 4%）。2018-2019年分两次（芽膨期和绿尖期）喷施营养液。在盛开阶段收集含有花蕾的刺。马刺段暴露于三种不同的冷冻测试温度（0、-2 和 -4 °C），并评估了一些相关的生理化学变化。K2SO4，特别是4%K2SO4的应用，降低了冻害、电解液泄漏率、过氧化氢（H2O2）、与对照相比，冷冻试验后花朵的丙二醛 (MDA) 浓度和丙二醛 (MDA) 浓度。营养处理，尤其是4%的K2SO4，显着提高了花的可溶性蛋白质、可溶性碳水化合物、总酚类化合物和脯氨酸的含量。本研究的结果可能对在低温地区种植的其他温带果树的抗冻性提高中钾的使用具有影响。