ITS Sequencing Reveals the Changing Characteristics of Fungal Communities in Different Rice-Growing Substrates Under Salt Stress

The impact of substrates with different physicochemical properties on the response of rhizosphere fungi in rice to salt stress has not been fully explored. The purpose of this study is to reveal the adaptation characteristics of fungal colonies to salt stress under different substrate conditions and the relationship between different properties of substrates and fungal colonies. Four different substrates were set by adjusting the sand, peat moss, and laterite ratio, with different bulk density, total porosity, and nutrient content. The same dose of sodium chloride solution was added to each substrate, and water was used as the control. The results showed that salt stress did not cause significant changes in the diversity and richness of fungal communities in different substrates. This study found that the responses of Ascomycota and <i>Penicillium</i> to salt stress varied depending on the substrate. The abundance of <i>Penicillium</i> was significantly positively correlated with total porosity (saline or non-saline conditions), but that of <i>Acrostalagmus</i> was significantly negatively correlated with total porosity under non-saline conditions. In addition, Lefse multi-level species difference discrimination analysis identified biomarkers in different treatments and revealed the core communities in response to substrate changes or salt stress. The results of this study contribute to a deeper understanding of the ecological functions of fungi.