Arbuscular common mycorrhizal networks mediate intra- and interspecific interactions of two prairie grasses

Abstract

Arbuscular mycorrhizal fungi form extensive common mycorrhizal networks (CMNs) that may interconnect neighboring root systems of the same or different plant species, thereby potentially influencing the distribution of limiting mineral nutrients among plants. We examined how CMNs affected intra- and interspecific interactions within and between populations of Andropogon gerardii, a highly mycorrhiza dependent, dominant prairie grass and Elymus canadensis, a moderately dependent, subordinate prairie species. We grew A. gerardii and E. canadensis alone and intermixed in microcosms, with individual root systems isolated, but either interconnected by CMNs or with CMNs severed weekly. CMNs, which provided access to a large soil volume, improved survival of both A. gerardii and E. canadensis, but intensified intraspecific competition for A. gerardii. When mixed with E. canadensis, A. gerardii overyielded aboveground biomass in the presence of intact CMNs but not when CMNs were severed, suggesting that A. gerardii with intact CMNs most benefitted from weaker interspecific than intraspecific interactions across CMNs. CMNs improved manganese uptake by both species, with the largest plants receiving the most manganese. Enhanced growth in consequence of improved mineral nutrition led to large E. canadensis in intact CMNs experiencing water-stress, as indicated by C isotope abundance. Our findings suggest that in prairie plant communities, CMNs may influence mineral nutrient distribution, water relations, within-species size hierarchies, and between-species interactions.

Are two strategies better than one? Manipulation of seed density and soil community in an experimental prairie restoration

“…The only case with a statistical interaction between treatments was in the seeded grasses, which had higher percent cover in the inoculated plots only in the lower density forb seeding treatment. The result at high‐density seeding is in contrast to studies that have found benefits of inoculation to native prairie grasses used in our study, such as A. gerardii (Schultz et al ; Shivega & Aldrich‐Wolfe ; Weremijewicz et al ). However, these studies do not consider seeding density, and thus may be more comparable with the low‐density treatment.…”

Effect of Arbuscular Mycorrhizal Fungi (AMF) and Plant Growth-Promoting Bacteria (PGPR) Inoculations on Elaeagnus angustifolia L. in Saline Soil

“…Total leaf area was scanned by an Epson Expression 1480 digital scanner (Epson (China) Co., Beijing, China) and measured by the measurement tool in Adobe Photoshop CS4 software (Version 11.0.1). Plant fresh mass was measured at final harvest, plant dry mass was determined and calculated after oven drying at 60 • C to constant mass [35]. The degree of succulence was expressed as the ratio of fresh mass to dry mass [36,37].…”

Contrasting effects of host identity, plant community, and local species pool on the composition and colonization levels of arbuscular mycorrhizal fungal community in a temperate grassland

“…AMFs trade acquired soil phosphorus (P) and nitrogen (N) with their hosts for photosynthetically fixed carbon (C) (B€ ucking & Kafle, 2015;Konvalinkov a et al, 2017). Additionally, AMFs affect water transport to plants (Mariotte et al, 2015), competition between plants (Weremijewicz et al, 2018), and their resistance to herbivores (Middleton et al, 2015). Despite most AMF species being able to enter symbiosis with most mycorrhizal hosts in a plant community, there seem to be important differences for both partners in the profitability of particular fungus-plant combinations (Bever et al, 1996;Klironomos, 2003).…”