Harmonizing Growth Symphony: Unraveling the Intricacies of Apricot Seedling Enhancement Through Humic Acid and Silicon Applications

Understanding the physiological responses of apricot (Prunus armenica L.) seedlings to treatments involving Humic Acid (HA), Silicon (Si), and their combination (HA + Si) is crucial for advancing sustainable agricultural practices. Focused on growth parameters, physiological attributes, and leaf mineral concentrations, this study addressed critical knowledge gaps in the influence of these treatments on apricot seedlings. The study highlighted a significant increase in stomatal conductance (SC), with the combined HA + Si treatment displaying the highest SC value at 303.98 mmol.m^-2s^-1. In contrast, control seedlings of the Alyanak apricot cultivar showed the lowest SC, registering at 122.52 mmol.m^-2s^-1. Regarding chlorophyll concentrations, the Şekerpare apricot cultivar treated with HA + Si achieved the highest value of 43.74, while in the Alyanak apricot cultivar, the Si treatment alone marked the second highest concentration at 43.02. The combined treatment (HA + Si) also reduced leaf temperatures (32.28 °C), notably in apricot cultivar Hacıhaliloğlu. Visual evaluation analyses underscored significant increases in Leaf Area (LA), Total Leaf Number (TLN), Shoot Length (SL), and other parameters, with the combined HA + Si treatment consistently outperforming individual ones. Mineral analysis revealed elevated Nitrogen (N) and Phosphorus (P) with HA, increased Magnesium (Mg) with Si and HA + Si, and significant effects on Potassium (K) and Calcium (Ca). Principal Component Analysis (PCA) confirmed the positive impacts on overall plant performance, corresponding to a cumulative explanation of 53.82%. This study provided crucial insights for tailoring agricultural practices to optimize apricot seedlings growth, emphasizing the effectiveness of HA and Si treatments, particularly in combination, for enhanced physiological responses.