Arbuscular Mycorrhizal Fungi from Argentinean Highland Puna Soils Unveiled by Propagule Multiplication

Abstract

Low arbuscular-mycorrhizal (AM) sporulation in arid field soils limits our knowledge of indigenous species when diversity studies are based only on spore morphology. Our aim was to use different approaches (i.e., spore morphological approach and PCR–SSCP (single-strand-conformation-polymorphism) analysis after trap plant multiplication strategies to improve the knowledge of the current richness of glomalean AM fungi (Glomerales; Glomeromycota) from the Argentine Puna. Indigenous propagules from two pristine sites at 3870 and 3370 m of elevation were multiplied using different host plants; propagation periods (2–6 months), and subculture cycles (1; 2; or 3) from 5 to 13 months. The propagule multiplication experiment allowed the detection of different glomoid taxa of Funneliformis spp. and Rhizoglomus spp., which were considered cryptic species since they had never been found in Puna soils before. On the other hand; almost all the generalist species previously described were recovered from cultures; except for Glomus ambisporum. Both plant host selection and culture times are critical for Glomerales multiplication. The SSCP analysis complemented the morphological approach and showed a high variability of Glomus at each site; revealing the presence of Funneliformis mosseae. This study demonstrates that AMF trap culture (TC) is a useful strategy for improving the analysis of AM fungal diversity/richness in the Argentinean highlands.

Multiplicación masiva de hongos micorrícicos arbusculares aislados de suelos cultivados con cacao

“…Este hecho podría explicar la razón por la que en Mariscal Cáceres se obtuvo el mayor número de esporas de HMA. Covacevich et al (2021) enfatizaron la importancia de combinar plantas hospedantes y ciclos de multiplicación de HMA; por su parte, Hernández et al ( 2006) realizaron un estudio de inoculación micorrícica y su efecto en el crecimiento de dos leguminosas, Acacia farnesiana y Prosopis glandulosa en el cual encontró una colonización entre 61,7 y 67,2 %; del mismo modo Sandoval (2019) obtuvo 72,89 % de colonización con Centrosema macrocarpum. Por tanto, de acuerdo a este estudio, usar cultivos hospederos incluidos en la familia Poaceae, es una buena estrategia para multiplicar propágulos de HMA en el suelo y por tanto producir inóculo, aunque las plantas sean distintas en género y especie.…”

Dry-Season Soil and Co-Cultivated Host Plants Enhanced Propagation of Arbuscular Mycorrhizal Fungal Spores from Sand Dune Vegetation in Trap Culture

“…On the other hand, trap culture causes the alteration of AMF composition in the starter soil by introducing some AMF species or recovering some hidden AMF species [ 68 ]. Furthermore, trap culture of AMF propagules from natural habitats brings about the detection of some AMF species described as cryptic since they are not initially detected in the starter soil [ 14 , 69 ].…”

The Diversity of Arbuscular Mycorrhizal Fungi and Their Associations in South America: A Case Study of Argentinean and Brazilian Cattle Raising Productive Ecosystems: A Review

“…Furthermore, Glomeraceae is a family that thrives in nutrient-rich environments and survives against major soil disturbances, such as those that occur in agroecosystems [112,113] but also in harsh natural ecosystems such as montane and highland grasslands in the arid ecosystems of Argentina and Brazil in South America [71,85]. Moreover, Glomeraceae has short life cycles with rapid growth and abundant production of spores [101,114,115]; these characteristics are consistent with a ruderal life strategy [116] that allows them a rapid and wide distribution at the ecosystem level but also biogeographically, being found in almost all the biomes of South America, the neotropics, and worldwide [39,117,118]). In the analyzed grasslands, Gigasporaceae plays the role of the edaphophilic guild [94] with the function of increasing the uptake of nutrients in the host plant, mainly benefiting those plants with thick roots, poorly adapted to nutrient absorption, and that depend on AMF for their nutrition, as is the case of C 4 grasses that are obligate mycotrophs [82][83][84]; also, this is a competitive family [116] with low abundance and species richness in arid environments [94].…”