Contents lists available at ScienceDirect Applied Soil Ecology journal homepage: www.elsevier.com/locate/apsoil Soybean yield, protein content and oil quality in response to interaction of arbuscular mycorrhizal fungi and native microbial populations from mono- and rotation-cropped soils Nicolás Marro a, ⁎ , Noelia Cofré a , Gabriel Grilli a , Carolina Alvarez b , Diana Labuckas a , Damián Maestri a , Carlos Urcelay a a Instituto Multidisciplinario de Biología Vegetal (IMBIV), CONICET, FCEFyN, Universidad Nacional de Córdoba, CC, 495, 5000, Córdoba, Argentina b EEA INTA Manfredi, Ruta Nac. N° 9 km 636, CP 5988 Manfredi, Córdoba, Argentina ARTICLE INFO Keywords: Arbuscular mycorrhizal fungi Soil biota Soil management practices Protein content Oil concentration Fatty acid composition ABSTRACT Two main soil management practices are generally used for soybean production: monoculture (MC) and crop rotation (CR). These strategies have different impacts on soil microbial communities. Among them, arbuscular mycorrhizal fungi (AMF) are well known to provide access to nutrients in a majority of cultivated plants. AMF communities have been shown to be more diverse in CR than in MC. Because AMF species differ in their effects on nutrition and development of plants, it could be expected that soil biota from different soil management practices affect soybean yield and quality. Therefore the objective of this study was to examine the combined effects of soil microbial communities and soil management practices (MC and CR) on yield, protein content, and oil quality of soybean grown under greenhouse conditions. The effects of three soil treatments, namely: sterile (S); microorganisms without AMF (MO); and microorganisms with AMF (AMF) were evaluated. These treatments were applied to soils from two crop management practices (CR and MC). Sterile soil promoted lower numbers of pods and seed weight per plant in MC but not in CR. AMF showed increased seed protein content (12–14%) whereas MO presented increased oil concentration (20–27%) (mainly within CR). Soybean grown with AMF from CR soil showed significantly higher amounts of oleic acid (21–25%), and lower linoleic acid (9%) when compared with other treatments. Findings from this study suggest that soybean yield and quality are affected by crop management practices and soil biota composition. Further, these parameters should be considered at the time of selecting agricultural strategies. 1. Introduction It has been shown that soil biota play a key role in crop productivity (Bender and van der Heijden, 2015; Zhang et al., 2019). Among soil microorganisms, arbuscular mycorrhizal fungi (AMF) are one of the most widespread plant root symbionts. They establish symbiosis with the majority of land plants, including cultivated ones. In exchange for carbon, they confer benefits to plants, including access to soil nutrients (e.g. Smith et al., 2003) and protection against soil-borne pathogens like nematodes (Marro et al., 2014, 2018). The benefits of AMF vary among species, and the composition of fungal communities in the soil may be relevant for crop productivity. Some studies have shown that more diverse AMF communities support higher plant growth (Hoeksema et al., 2010; Wagg et al., 2011; Zhang et al., 2019). Compared with monoculture, rotational cropping promotes greater AMF diversity due to the presence of plant hosts with differential affi- nities for distinct AMF species (Oehl et al., 2003, 2010; Hijri et al., 2006). Together these findings suggest that cropping systems can affect crop yield via changes in AMF composition, although recent debates challenge this idea (see Ryan and Graham, 2018; Rillig et al., 2019). Despite the global importance of soybean (Glycine max (L.) Merrill) production, this crop is generally less studied than others in compara- tive analyses (e.g. Zhang et al., 2019). Soybean is one of the most im- portant crops in the world as a source of oil and protein for humans, but also as livestock feed (Masuda and Goldsmith, 2009). For this crop, no- tillage (NT) is the most widespread agricultural practice (Albertengo https://doi.org/10.1016/j.apsoil.2020.103575 Received 18 October 2019; Received in revised form 4 February 2020; Accepted 1 March 2020 Abbreviations: MC, monoculture; CR, crop rotation; NT, no–tillage; S, sterile soil; MO, soil microorganisms without arbuscular mycorrhizal fungi; AMF, soil microorganisms with arbuscular mycorrhizal fungi; FA, fatty acid; GC, gas chromatography ⁎ Corresponding author. E-mail address: nmarro@imbiv.unc.edu.ar (N. Marro). Applied Soil Ecology 152 (2020) 103575 0929-1393/ © 2020 Elsevier B.V. All rights reserved. T