Metabolic Responses of Haloxylon Salicornicum to Diurnal and Seasonal Variations in a Desert Environment

Haloxylon salicornicum is a desert plant well-adapted to extreme arid environments. This study explores how this species adjusts its metabolism in response to diurnal and seasonal environmental changes. Herein, we examined its metabolic responses across two soil types (clay and sandy), two seasons (winter and summer), and two timings (dawn and midday), focusing on water status and primary metabolites’ profiling via untargeted metabolomics.The variation in soil properties at 1 m depth did not significantly affect the metabolic responses of H. salicornicum plants, while notable changes occurred across seasons and timings. During winter, the plants’ water status was relatively higher (water potential − 1 MPa), facilitating the activation of anabolic pathways, specifically carbon fixation and the biosynthesis of carbohydrates and amino acids, thereby allowing growth and accumulation of reserves. In summer, however, water potential decreased sharply ( − 5 MPa), leading to the stimulation of catabolic processes, particularly starch breakdown, to sustain carbon metabolism and maintain energy production. Additionally, the plants accumulated antioxidants like ascorbate, glutathione, and caffeic acid to combat oxidative stress caused by heat and drought. Overall, H. salicornicum exhibited remarkable metabolic flexibility, especially through nocturnal activity, to survive harsh desert conditions. These findings contribute to understanding the mechanisms by which desert plants endure extreme stress and lay the groundwork for future genetic studies.