YIELD AND QUALITY OF Thymus vulgaris L. OIL, UNDER THE EFFECT OF MYCORRHIZIC FUNGI, RHIZOBACTERIA AND PHYTOREGULATORS

Abstract

Thyme (Thymus vulgaris L.) is commercialized mainly for its leaves and essential oil, and because of the growing demand of natural ingredients and high-quality oils, the effect of applying a commercial phytorregulator and inoculating with plant growth-promoting rhizobacteria (PGPR) and arbuscular mycorrhizae fungi (AMF) on the yield and composition of the essential thyme oil, was evaluated, highlighting the first indication of the impact of symbiotic relationships on the species with the production and quality of the oil, under a completely random experimental design with 32 repetitions for each treatment. The planting distance was 1.5x1.0 m between rows and plants, respectively. The greatest yield was presented by the inoculation treatment with bacteria P61 with 13.3 mg AE g^-1 MS. It was observed that the number of components and the percentage present in the essential oil is different in each treatment. The highest concentration of thymol was seen in the Control (52.55 %), followed by plants inoculated with P61 (51 %) and AMF Zac19+Cedar (50.66 %). For ocimene, the treatment inoculated with AMF Zac19 (21.79 %) presented the highest concentration, followed by AMF Zac19+Cedar and phytoregulator Bioforte®, with 20.38 % and 19.37 %, respectively. With regard to the concentration of J-terpinene, inoculation with AMF Cedar and bacteria P61 showed a better response with 17.9 and 17.84 %, respectively.