ARBUSCULAR MYCORRHIZAL FUNGI COMMUNITIES AND INFECTIVITY IN THREE FRAGMENTS OF URBAN FOREST IN CÓRDOBA CITY (ARGENTINA).

BUIL P., RENISON D. & BECERRA A

Congreso; Congreso Argentino de Microbiología General; 2018

In many countries urban forests and green infrastructures are threatened by the growth of cities, lack of investment and inadequate management to recover vital ecosystem services. Studies that address fungal biodiversity and especially that of arbuscular mycorrhizal fungi (AMF) in these areas are scarce. AMF are fundamental for plant development, especially in degraded soils, where reforestation is necessary. Here, we analyze AMF composition and mycorrhizal infectivity in three sites of urban forest with different land management: a protected forest with 10 years of exclosure to the public, a restored forest with an herbaceous stratum and a restored forest with thinned herbaceous stratum (lawn) removed regularly. In seven soil samples from each situation we evaluated diversity, richness and abundance of morphotypes, edaphic properties, soil compaction and % plant cover (herbaceous, shrub and arboreal strata). Infectivity was evaluated in Medicago sativa (alfalfa) plants harvested at 15, 30 and 60 days, at different concentrations of the soil (1:0; 1:4; 1:40) in a greenhouse assay. We evaluated differences by means of analysis of variance (ANOVA or Kruskal-Wallis test). Richness values were different between the three sites, with 14 species in the restored forest with an herbaceous stratum and only 11 and 9 species for the protected forest and the restored forest with thinned herbaceous stratum respectively, which could be due to historical and structural differences such as the different variety and age of plant species. Diversity and abundance did not show significant differences between sites. The most represented families of AMF in the three sites were Glomeraceae, Claroideoglomeraceae and Acaulosporaceae, whose species are considered generalists and resilients to disturbances. Infectivity was different only by the 1:4 treatment in the protected forest site (59% at 30 days). There we registered the lowest soil compaction and the dominance of the arboreal stratum, which would benefit the colonization of M. sativa roots. Finally, we discuss the need for long-term studies to understand the temporal and spatial dynamics of AMF in urban areas, their study in native flora and their potential role in reforestation strategies of the scarce green areas in the city of Córdoba.