Assessment of Morphological, Physiological, and Biochemical Characteristics of Thymus kotschyanus Bioss. and Hohen under Different Bio and Chemical Fertilizers

Biofertilizer has been recognized as an alternative to chemical fertilizer to improve soil fertility and crop production in sustainable agriculture. The objective of this field study was to evaluate the effects of bio and chemical fertilizer on qualitative and quantitative characteristics of Thymus kotschyanus Bioss. & Hohen. The experiment was conducted during 2019 at Imam Khomeini International University, Qazvin, Iran, and treatments included control (no fertilizer), chemical fertilizer (NPK), and four types of microorganisms including Funneliformis mosseae (AMF), Azotobacter chroococcum strain 5, Pseudomonas stutzeri strain P-16, and Pseudomonas putida strain 41. The results showed that AMF and NPK positively affected plant height, number of branches per plant, and photosynthesis pigments contents compared to other treatments. However, maximum plants’ fresh and dry weight, proline, total phenolic and flavonoid contents, DPPH inhibition, essential oil percentage, and carvacrol quantity were obtained from plants that were inoculated with AMF. Also, the activities of Catalase (CAT) and Superoxide Dismutase (SOD) were increased by the application of AMF. According to the obtained results, there were no significant differences in P concentration between plants treated with P. stutzeri, Pseudomonas putida, AMF, and NPK. Maximum N amount in T. kotschyanus leaf was obtained in plants treated with AMF, NPK and Azotobacter chroccucum. Plants inoculated with AMF had higher Ca uptake compared to the other treatments, and the maximum total K accumulation in T. kotschyanus were obtained in plants inoculated with AMF and NPK. Hence, the use of organic and biological inputs instead of chemical fertilizer for improving crop efficiency and quality with the aim of alleviating pollution and accomplishing sustainable agriculture is highly encouraging.