| Abstrakt: |
In recent years, the use of indigenous isolates of fluorescent pseudomonads to improve essential oils (EOs)’ quantity and quality of various medicinal plants has been considered. In present study, samples were taken from the rhizosphere of Satureja rechingeri plants located in the habitats of Ilam province, Iran. By producing fluorescent green pigment in King's B medium, fluorescent pseudomonads were screened. From the total of 22 isolates, PF4, PF11, and PF19 were recognized as the superior isolates due to producing the highest amount of pigment and were identified with the help of biochemical tests. The 16-leaf seedlings of savory were transferred to the field two months after planting the seeds in the greenhouse. Each of the two-year-old plants was treated with a suspension (107 CFU/ml) of the superior isolate, by adding it to the soil in a randomized complete block design (n=3). Seven months after applying the treatments, which coincided with full flowering stage in the third year of planting, EO was extracted from the flowering branches by water distillation method. The main components of the EOs were identified with the GC-FID set. The percentage yield of the EO was calculated based on the plant dry weight. According to the results, PF4, PF11, and PF19 belonged to biovars II, III, and V of Pseudomonas fluorescens, respectively. Based on GC-FID analysis, several compounds such as carvacrol, alphathogen, alpha-pinene, myrcene, para-cymene, gamma-terpinene, terpinolene, linalool, trans-caryophyllene, beta-bisabolene, and spatholenol were detected in Reshingari's EO. The carvacrol amount as the main component of EO increased from 82.8% in control to 91.7% in PF11 treatment. The percentage of plants’ EO yield increased from 3.02% in the control to 4.4% in the PF11 treatment, significantly (P<0.05). Therefore, the application of the indigenous and compatible Ps. fluorescens isolate PF11 is recommended to improve the phytochemical yield of Reshingari savory under field conditions. [ABSTRACT FROM AUTHOR] |
