Arbuscular mycorrhizal fungi inoculation of winter wheat in an intensive crop producing farm

Abstract

Arbuscular mycorrhizal fungi (AMF) inoculation represents a valid tool for improving crop yield, primarily in the case of extensive crop production. The conditions of intensive crop production inhibit the growth of AMF and decrease the plant root mycorrhization. To clarify the possibilities of AMF inoculation under intensive farm conditions, a two-year field experiment was set up. The effect of AMF inoculation and mineral fertilization (130 kg N ha-1, 78 kg P2 O5 ha-1, 60 kg K2 O ha-1) were investigated on the crop yield, crop P content and root mycorrhization of two modern winter wheat (Triticum aestivum L.) cultivars. The soil was Chernozem with calcareous precipitates (WRB classification: Calcic Chernozem). The AMF inoculum contained reproductive units of Rhizophagus irregularis and Glomus mosseae. The whole experimental area was 32 ha and cultivated according to the usual intensive crop production of the farm. Both AMF inoculation and mineral fertilizer treatment had a significant effect on crop yield and root mycorrhization. The yield-enhancing effect of AMF inoculation was only observed in plots without mineral fertilizer and depended on the interaction of the year and the cultivar. AMF inoculation did not affect the P content of the crop. In the dry year the effect of AMF inoculation was cultivar dependent. AMF inoculation increases the yield to a smaller extent than the mineral fertilization. Our results show that AMF inoculation without fertilization can be profitable under intensive farming conditions.