Changes of microflora of wheat roots after foliar application of urea

Upper parts of wheat grown in containers with brown soil were four-times repeatedly treated with a solution of urea. The foliar application of urea resulted in a considerable increase of the number of bacteria in the roots and a decrease of the number of fungi. Seventeen and 13 genera of fungi could be detected in the rhizosphere of the treated plants, 3 and 5 weeks, respectively, after the application, whereas 23 and 16 genera could be identified in the rhizoplane of the treated plants. Fungi of the generaFusarium andPenicillium predominated in the root region. The foliar application of urea resulted in an increased relative occurrence of the genusFusarium and decreased relative representation of the genusPenicillium. Changes in the relative occurrence of other 18 genera of fungi present in small quantities on wheat roots could also be observed. The foliar application of urea affected not only numbers of fungi determined by the dilution plate method but also the occurrence of active hyphae.