The effect of tillage and no-tillage system on culturable fungal communities in the rhizosphere and soil of two spelt cultivars

Abstract

A return to old species cultivated in the past, especially those with high health-promoting and nutritional values, such as spelt (Triticum aestivum ssp. spelta) is being increasingly observed. In addition, due to the increasing use of soil protective cultivation systems in recent years, such as no-tillage cultivation or direct sowing, the aim of the study was to assess the mycobiota of spelt rhizosphere and root-free soil, determine the ratio of potentially pathogenic to antagonistic fungi and assess the impact of cultivation systems on the frequency and biodiversity of fungi. The frequency and species composition were examined in 3-years cultivation of two spelt cultivars. The total number of rhizosphere fungi was significantly higher in the no-tillage system and under the spelt cultivar Franckenkorn compared to the tillage system and the cultivar Badengold. The species richness of the analyzed experimental variants was similar. The dominant group of fungi was the order Hypocreales (Ascomycota). Ninety-five percent of the fungal population from the rhizosphere and 88% of fungi from root-free soil belonged to rare (1–5%) or sporadic species (<1%). Taxa with higher frequency (>5%) in the rhizosphere included: Clonostachys, Gibellulopsis, Rhizopus and Sarocladium, Mortierella, Mucor, Penicillium, Sarocladium and Trichoderma. The cultivation system and plant cultivar affected the occurrence and distribution of fungal populations in the rhizosphere and root-free soil. The similarity of species composition of fungal communities in the rhizosphere and root-free soil was low, while taking into account species frequency, their diversity was high. The ratio of antagonistic to potentially phytopathogenic fungi of spelt rhizosphere deteriorated in the 2nd and 3rd year of wheat cultivation.