Wheat production is influenced by changing environmental conditions, including climatic conditions, which results in the changing composition of microorganisms interacting with this cereal. The group of these microorganisms includes not only endophytic fungi associated with the wheat endosphere, both pathogenic and symbiotic, but also those with yet unrecognized functions and consequences for wheat. This paper reviews the literature in the context of the general characteristics of endophytic fungi inhabiting the internal tissues of wheat. In addition, the importance of epigenetic regulation in wheat–fungus interactions is recognized and the current state of knowledge is demonstrated. The possibilities of using symbiotic endophytic fungi in modern agronomy and wheat cultivation are also proposed. The fact that the current understanding of fungal endophytes in wheat is based on a rather small set of experimental conditions, including wheat genotypes, plant organs, plant tissues, plant development stage, or environmental conditions, is recognized. In addition, most of the research to date has been based on culture-dependent methods that exclude biotrophic and slow-growing species and favor the detection of fast-growing fungi. Additionally, only a few reports of studies on the entire wheat microbiome using high-throughput sequencing techniques exist. Conducting comprehensive research on the mycobiome of the endosphere of wheat, mainly in the context of the possibility of using this knowledge to improve the methods of wheat management, mainly the productivity and health of this cereal, is needed.

The occurrence and diversity of Lecanicillium and Sarocladium in maize seeds and their role in this cereal are poorly understood. Therefore, the present study aimed to investigate Sarocladium and Lecanicillium communities found in endosphere of maize seeds collected from fields in Poland and their potential to form selected bioactive substances. The sequencing of the internally transcribed spacer regions 1 (ITS 1) and 2 (ITS2) and the large-subunit (LSU, 28S) of the rRNA gene cluster resulted in the identification of 17 Sarocladium zeae strains, three Sarocladium strictum and five Lecanicillium lecanii isolates. The assay on solid substrate showed that S. zeae and S. strictum can synthesize bassianolide, vertilecanin A, vertilecanin A methyl ester, 2-decenedioic acid and 10-hydroxy-8-decenoic acid. This is also the first study revealing the ability of these two species to produce beauvericin and enniatin B1, respectively. Moreover, for the first time in the present investigation, pyrrocidine A and/or B have been annotated as metabolites of S. strictum and L. lecanii. The production of toxic, insecticidal and antibacterial compounds in cultures of S. strictum, S. zeae and L. lecanii suggests the requirement to revise the approach to study the biological role of fungi inhabiting maize seeds.

The role of the microbiome in the root zone is critically important for plants. However, the mechanism by which plants can adapt to environmental constraints, especially water deficit, has not been fully investigated to date, while the endophytic core microbiome of the roots of spelt (Triticum aestivum ssp. spelta L.) grown under drought conditions has received little attention. In this study, we hypothesize that differences in the endophytic core of spelt and common wheat root microbiomes can explain the variations in the growth and photosynthetic activity of those plants, especially under drought conditions. Our greenhouse experimental design was completely randomized in a 2 × 4 × 3 factorial scheme: two water regime levels (well-watered and drought), three spelt varieties (T. aestivum ssp. spelta L.: ‘Badenstern’, ‘Badenkrone’ and ‘Zollernspelz’ and one wheat variety: T. aestivum ssp. vulgare L: ‘Dakotana’) and three mycorrhizal levels (autoclaved soil inoculation with Rhizophagus irregularis, control (autoclaved soil) and natural inoculation (non-autoclaved soil—microorganisms from the field). During the imposed stress period, relative water content (RWC), leaf chlorophyll fluorescence, gas exchange and water use efficiency (WUE) were measured. Microscopic observations of the root surface through fungi isolation and identification were conducted. Our results indicate that ‘Badenstern’ was the most drought tolerant variety, followed by ‘Zollernspelz’ and ‘Badenkrone,’ while the common wheat variety ‘Dakotana’ was the most drought sensitive. Inoculation of ‘Badenstern’ with the mycorrhizal fungi R. irregularis contributed to better growth performance as evidenced by increased whole plant and stalk dry matter accumulation, as well as greater root length and volume. Inoculation of ‘Zollernspelz’ with arbuscular mycorrhizal fungi (AMF) enhanced the photochemical efficiency of Photosystem II and significantly improved root growth under drought conditions, which was confirmed by enhanced aboveground biomass, root dry weight and length. This study provides evidence that AMF have the potential to be beneficial for plant growth and dry matter accumulation in spelt varieties grown under drought conditions.

The online version contains supplementary material available at 10.1007/s00248-026-02731-4.