The rapid ripening and fruit size are two important factors, which significantly influence the economy and marketability of apricot. Generally, the postharvest quality of fresh crops depends on the quality achieved at harvest time, which is influenced considerably by pre-harvest factors. Therefore, this study aimed to investigate the effect of foliar application of calcium chloride and potassium nitrate on the physical and biochemical attributes of apricot fruit. We evaluated the effect of foliar sprays of 0.5% or 1% calcium chloride (CaCl₂) and 1% or 2% potassium nitrate (KNO₃) on the yield and at harvest quality of apricot fruits cv. ‘Shahroudi’ during the 2019 and 2020 growing seasons. The experiment was conducted in a commercial apricot orchard located in Birjand, Iran. The results indicated that twice foliar spray of both chemicals at the pre-harvest stage affected most of the evaluated traits in both years. KNO₃ application at both concentrations significantly increased the length, width, and weight of apricot fruit and maintained total phenol content, vitamin C, and titratable acidity compared to the control. Interestingly, treated fruit with KNO₃ solution at both concentrations increased fruit width (150%), fruit length (160%), and fresh fruit weight (180%), compared to the control. Besides, KNO₃ (1% or 2%) and 1% CaCl₂ treatments significantly increased fruit firmness (25%) and calcium content (35%) of fruit pulp compared to the control. Overall, the results suggest practical multiple practical application of both chemicals (particularly KNO₃) at proper concentration and time during the growth season to improve the quality and increase the yield of apricot fruit ‘Shahroudi’ cultivar.

快速成熟和果实大小是两个重要因素，它们显着影响杏子的经济性和适销性。通常，新鲜农作物的收获后质量取决于收获时达到的质量，收获前的因素对收获质量有很大影响。因此，本研究旨在研究叶面施用氯化钙和硝酸钾对杏果实理化特性的影响。我们评估了叶面喷洒0.5％或1％的氯化钙（CaCl ₂）和1％或2％的硝酸钾（KNO ₃）杏果实简历的产量和收获质量。在2019年和2020年生长季节的``Shahroudi''。该实验是在位于伊朗比尔詹德的一个商业杏园中进行的。结果表明，在收获前两次叶面喷洒两种化学物质都会影响这两年中大多数被评估的性状。与对照相比，两种浓度的KNO ₃施用均显着增加了杏果实的长度，宽度和重量，并保持了总酚含量，维生素C和可滴定的酸度。有趣的是，与对照相比，在两种浓度下用KNO ₃溶液处理的水果均增加了水果宽度（150％），水果长度（160％）和新鲜水果重量（180％）。此外，KNO ₃（1％或2％）和1％CaCl与对照组相比，_两种处理均显着提高了果肉的水果硬度（25％）和钙含量（35％）。总体而言，结果表明在生长季中以适当的浓度和时间对两种化学品（尤其是KNO ₃）进行了多种实际应用，以提高品质并提高杏果实“ Shahroudi”品种的产量。