Endophytic fungus diversity in soybean plants submitted to conditions of elevated atmospheric CO₂ and temperature

Abstract

Global climatic changes can have drastic impacts on plant species including severe consequences for the agricultural species productivity. Many of these species present important mutualisms with endophytic fungi that positively influence their performance. The present study evaluated whether the increases in CO<sub>2</sub> and temperature predicted for the year 2100 may cause changes in foliar carbon (C) and nitrogen (N) concentrations in soybean (<i>Glycine max</i>) and, consequently, the interactions with its endophytic fungi. The effects of elevated CO<sub>2</sub> and temperature were evaluated in four treatments in open-top chambers: (1) Control; (2) Increased Temperature; (3) Increased CO<sub>2</sub>; (4) Increased CO<sub>2</sub> and Temperature. Increased atmospheric CO<sub>2</sub> resulted in decreased foliar nitrogen concentration, while increased temperature increased it. A total of 16 taxa of endophytic fungi were identified based on sequencing <i><i>ITS</i></i> (Internal Transcribed Spacer) regions of rRNA subunits. Increased atmospheric CO<sub>2</sub> and temperature were observed to potentially modify the endophytic mycobiota of soybean plants. Results suggest the fungi species substitution as a consequence of changes in foliar nitrogen concentration and C:N ratio. Predicted climatic changes shall affect the plant and endophytes relationships, which will in turn affect the performance and resistance of soybean, one of the most important crops in the world.

Manipulating atmospheric CO2 concentration induces shifts in wheat leaf and spike microbiomes and in Fusarium pathogen communities

“…Similarly, the shift in microbiome communities under elevated [CO 2 ] identified in both tissue types likely reflected the unique changes in those microbial habitats. Recent work shows that nutritional properties of wheat grain are often altered by elevated [CO 2 ] ( Hay et al, 2020 ), while foliar N is known to decrease dramatically under elevated [CO 2 ] in C 3 crops ( Gonçalves et al, 2021 ).…”

“…Taxa belonging to the phylum Basidiomycota tended to experience more dramatic shifts in abundance between [CO 2 ] treatments, relative to taxa from Ascomycota, but while some taxa were enriched under elevated [CO 2 ], others were depleted. The responses of microbial taxa to elevated [CO 2 ] may be dependent on the plant response to [CO 2 ], such as immune response ( Zhou et al, 2019 ), change in nutritional status ( Hay et al, 2020 ; Gonçalves et al, 2021 ), or change in stomatal openings ( Huang et al, 2018 ). Shifts in the abundance of individual microbial taxa may also depend on the positive and negative associations among the microbiota themselves ( Connor et al, 2017 ).…”

Endophytic fungi of soybean (Glycine max (L.) Merr.) and their potential applications

“…Endophytes are ubiquitous microbes that live in the intercellular space of plant tissues including leaves, seeds, stems, and roots without causing apparent disease in the host plant (Abo-Elyousr et al 2014;Grabka et al 2022). Endophytes provide lots of benefits to their host plants, including reduction of plant pathogens (Arnold et al 2003;Gonçalves et al 2021), fixing nitrogen, production of phytohormones (Azevedo 2014;Gonçalves et al 2021), increasing environmental stress resistance (Schardl et al 2004), increasing plant nutrient intake (White et al 2019), and potentially regulating the plant growth and development (Irizarry and White 2018). In the future, endophytes may contribute to the reduction of chemicals (i.e., fertilizers, fungicides, insecticides, or herbicides) used in crop cultivation (White et al 2019).…”

“…In the future, endophytes may contribute to the reduction of chemicals (i.e., fertilizers, fungicides, insecticides, or herbicides) used in crop cultivation (White et al 2019). Fungal endophytes interact with their host plants affecting their structural and chemical components (Gonçalves et al 2021). Recent studies showed that the association of fungal endophytic communities with various plant species is underestimated, while the fungal diversity and distribution could be host and/or environment specific (Grabka et al 2022).…”

Elevated carbon dioxide reduces a common soybean leaf endophyte

“…Because of this, there is growing interest in how endophyte communities will respond to climate change (Rudgers et al, 2020; U’Ren et al, 2019), potentially in ways that can increase plant performance in the face of stressors such as drought (Giauque et al, 2019) and UV‐B radiation (Ramos et al, 2018), yet there has been no such investigation of the impact of rising [CO 2 ] on endophyte communities in field‐grown plants. A recent study examined how elevated temperature and [CO 2 ] interacted to affect endophyte colonization in highly controlled open‐top chambers within a greenhouse, and found minor differences between chambers (Gonçalves et al, 2021). More studies, particularly those under natural field conditions, are needed to more fully understand how major drivers of climate change, such as elevated [CO 2 ], impact how endophytes interact with their host plants and with each other.…”