Chemical Variation in the Essential Oil of Salvia leriifolia Benth. in Response to Organic and Biological Fertilizers

In order to study the effect of application of organic and biological fertilizers on leaf dry weight (LDW), essential oils content (EO), and composition of Salvia leriifolia Benth., a factorial experiment was carried out based on randomized complete block design with three replications and 10 treatments. The experiment was performed at Agricultural and Natural Resources Research and Education Center, Mashhad- Iran, during two growing seasons (2014-2015 and 2015- 2016). The treatments consisted of five levels of organic fertilizers [control (C0), compost 10 ton/ha (C10) compost 20 ton/ ha(C20), vermicompost three ton/ ha(V3) and vermicompost six ton/ ha(V6)] and Pseudomonas putida biofertilizer in two levels [Inoculation (S1) and without inoculation (S0)]. The results indicated that the highest LDW (1470 kg/ha) in the second year was obtained in C20S1, which increased by 47%, compared to C0S0, respectively. The EO in both growing seasons was not affected by the treatments. However, the application of 20 ton/ haof compost caused the EO yield was significantly higher than other treatments, except V6. A significant increase in LDW caused the highest EO yield of 5.0 and 5.9 kg/hawas obtained in C20S0 treatment in first and second growing seasons, respectively, which increased by 60% compared to the control (C0S0). The results showed that out of 99.9% of EO compounds, 95.6% including 33 identified compounds and only 4.2% contained other compounds. The valuable compounds of β-pinene (26.3%), 1,8-cineole (14.8%), α-pinene (13.8%) and Borneol (4.8%) have the highest percentage of EO compounds in the studied treatments. Organic fertilizer treatments had no significant effect on the four main compounds of S. leriifolia EO but increased Guaiol, Epi-α-eudesmol and δ-cadinol compared with control. The highest percent of Guaiol (2.3) and epi-α- eudesmol (3.2) were obtained in V6S1, respectively, which increased by 68% and 178% compared with control. Also, bacterial inoculation showed a significant difference with non-inoculation in Guaiol and epi-α- eudesmol using V6S1 treatment. Despite the increase in the percentage of these compounds, some of the EO compounds significantly decreased with the application of vermicompost treatments. Accordingly, Sabinene, epi-α-bisabolol compounds in V6S0 were decreased by 116% and 52%, respectively, and Terpine-4-ol and cis-sabinol compounds in V3S0 decreased by 21% and 19%, respectively, compared with control. Finally, the application of organic fertilizers had different effects on the S. leriifolia EO components, but the percent and amounts of all four main components were not affected by treatments.