Differential growth ofAtkinsonellaspecies on host grass calli

Echinacea purpurea microbiota: bacterial-fungal interactions and the interplay with host and non-host plant species in vitro dual culture

Important evidence is reported on the antimicrobial and antagonistic properties of bacterial endophytes in Echinacea purpurea and their role in the modulation of plant synthesis of bioactive compounds. Here, endophytic fungi were isolated from E. purpurea, and the dual culture approach was applied to deepen insights into the complex plant-microbiome interaction network. In vitro experiments were carried out to evaluate the species specificity of the interaction between host (E. purpurea) and non-host (E. angustifolia and Nicotiana tabacum) plant tissues and bacterial or fungal endophytes isolated from living E. purpurea plants to test interactions between fungal and bacterial endophytes. A higher tropism towards plant tissue and growth was observed for both fungal and bacterial isolates compared to controls without plant tissue. The growth of all fungi was significantly inhibited by several bacterial strains that, in turn, were scarcely affected by the presence of fungi. Finally, E. purpurea endophytic bacteria were able to inhibit mycelial growth of the phytopathogen Botrytis cinerea. Bacteria and fungi living in symbiosis with wild Echinacea plants interact with each other and could represent a potential source of bioactive compounds and a biocontrol tool.

The influences of fungal endophytes inoculation on the biochemical status of grape cells of different varieties in vitro

The metabolic patterns of grape cells can be specifically shaped by different strains of dual-cultured fungal endophytes. In this work, a solid co-culture system was furtherly proposed to illustrate the different impacts of endophytic fungi on the biochemical status of grape cells of different varieties. By measuring the metabolic impacts of contact fungal endophytes on grape cells of the varieties 'Rose honey' (RH) and 'Cabernet sauvignon' (CS), we observed that most of the fungal strains used had promoting effects on grape cellular biochemistry parameters. Compared with the control, inoculation with most of the fungal strains increased the superoxide dismutase (SOD) and phenylalanine ammonia-lyase (PAL) activities as well as the total flavonoid (TF) and total phenolics (TPh) contents in both types of grape cells. Among the tested strains, RH34, RH49 and MDR36 had relatively stronger biochemical impacts on grape cells. More interestingly, in addition to the varietal specificity, a certain degree of fungal genus specificity was also observed during the metabolic interactions between fungal endophytes and grape cells, as fungal endophytes from the same genus tended to be clustered into the same group based on the affected biochemical traits. This work revealed the differential biochemical status effects of fungal endophytes on different varietal grape cells and raised the possibility of reshaping grape qualities by applying endophytes.