Effects of Altitude on Some Physiological Characteristics of Sagebrush in Khorasan Province, Iran

The present research aimed to investigate the effects of altitude on some physiological characteristics of Artemisia aucheri Boiss. Plant samples were taken from 15 areas in the Lakh Kuhik mountains. After determining the maps of work units, samples were taken systematically in each unit. Data were analyzed using descriptive statistics in SPSS. The highest and the lowest chlorophyll content were recorded at an altitude below 1200 m and above 1256 m, respectively. Dry and fresh weights were measured with a precision balance. The results indicated a direct relationship between the increase in plant Ca2+, Mg2+, and K+ contents and altitude. However, there was no significant relationship between altitude and plant P3-. Extraction was performed using a rotary evaporator (rotovap). Physiological and antioxidant traits and chlorophyll content of the samples were determined using the standard method (i.e., by a spectrophotometer). Results indicated that altitude had significant effects on physiological traits as the highest antioxidant activity was observed in regions with mid-latitude regions (i.e., 1228 m). Overall, it can be concluded that antioxidant content was lower at higher altitudes, and the best quality could be obtained from higher altitude plants (i.e., 1256 m). Similarly, fresh and dry weights were higher at higher altitudes because cytokinin levels in plants increased with reductions in auxin levels. In the next step, chlorophyll a and chlorophyll b were assayed separately. The results revealed that the chlorophyll content declined at high altitudes due to the presence of shortwave radiation.