Allelopathic effects of Cnidium monnieri and Sophera flavescens on verticillium wilt (Verticillium dahliae) and microbial population in rhizosphere of eggplant

Allelopathic effects of Cnidium monnieri and Sophera flavescens on Verticillium wilt and microbial population in eggplant rhizosphere were investigated. The results showed that the extracts of C. monnieri and S. flavescens had dosedependent inhibitory effects on the mycelium growth of Verticillium dahliae. When the extract concentration of 200 mg^.L⁻¹ of C. monnieri was applied, no germination occurred. Eggplant growth (plant height, stem diameter and dry matter content) was improved compared to control (monocropping field). C. monnieri and S. flavescens treatments, influenced the population and composition of microorganisms in the rhizosphere. Addition of C. monnieri and S. flavescens extracts significantly decreased the fungi and bacteria populations, however, actinomycetes population was significantly increased. Highest microorganisms population was found at flowering stage. It seems that allelopathic substances released by C. monnieri and S. flavescens were suppressive to Verticillium dahliae.