Archivio Journal of Plant Pathology

Abstract:

Effects of farming system on the composition of the root-zone microbiota and on the occurrence of root and stem-base diseases in winter wheat cv. Rywalka were analysed. The wheat was grown in organic, integrated and conventional systems of production and in monoculture over three years. Using classical methods, saprotrophic and pathogenic microorganisms, mainly fungi, were isolated from the root zone and identified on the basis of morphology and, where possible, designated as potential pathogens or antagonists. In roots, rhizoplane, and rhizosphere and non-rhizosphere soil the total frequencies of dominants (with frequency >5%) was 80.7- 98.7% and subdominants (with frequency 1–5%) was 0.5-14.5% and were similar in all production systems. Potential major soil-borne pathogens included Fusarium + Haematonectria. Potential pathogen antagonists included Chaetomium, Clonostachys, Gliomastix, Sarocladium and Trichoderma species. The low ratio of fungal pathogens : antagonists (Fusarium + Haematonectria : Clonostachys + Trichoderma spp.) in soil associated with lowest incidence of root and stem-base diseases, lower occurrence of Fusarium and Rhizoctonia in root and stem-base region and highest yield of grain in a conventional system for production of wheat cv. Rywalka confirms the cultivar’s suitability for high-input conventional farming. Benefits of microbiological approaches in the study of suitability of cultivar to a particular farming system is demonstrated.