ABSTRACT
Abstract We investigated the composition and structure of fungal communities associated with leaf litter generated by Clusia nemorosa and Vismia guianensis that belong to phylogenetically-related botanical families and exist together in a remnant of the Atlantic Forest in Bahia, Brazil. Samplings were conducted during wet (June 2011) and dry (January 2013) seasons in Serra da Jibóia. The fungi were isolated using particle filtration and the 1,832 isolates represented 92 taxa. The wet season yielded the largest number of isolates (1,141) and taxa (76) compared with the dry season (641 isolates and 37 taxa). The richness and diversity of fungal species associated with C. nemorosa (64 taxa, Simpson=0.95)were higher compared with those of V.guianensis (59 taxa, Simpson =0.90). Analysis of similarity (ANOSIM) revealed significant variations in the composition and community structure of fungi isolated from the two plants as a function of seasons. In contrast, nonmetric multidimensional scaling (NMDS) analysis show that the seasonality was an important influence on the distribution of fungal species. However, the populations of the saprobic fungal communities were dynamic, and several factors may influence such communities in the Atlantic Forest.
Subject(s)
Brazil/classification , Brazil/genetics , Brazil/isolation & purification , Brazil/microbiology , Clusia/classification , Clusia/genetics , Clusia/isolation & purification , Clusia/microbiology , Clusiaceae/classification , Clusiaceae/genetics , Clusiaceae/isolation & purification , Clusiaceae/microbiology , Ecosystem/classification , Ecosystem/genetics , Ecosystem/isolation & purification , Ecosystem/microbiology , Forests/classification , Forests/genetics , Forests/isolation & purification , Forests/microbiology , Fungi/classification , Fungi/genetics , Fungi/isolation & purification , Fungi/microbiology , Plant Leaves/classification , Plant Leaves/genetics , Plant Leaves/isolation & purification , Plant Leaves/microbiology , Seasons/classification , Seasons/genetics , Seasons/isolation & purification , Seasons/microbiology , Trees/classification , Trees/genetics , Trees/isolation & purification , Trees/microbiologyABSTRACT
Abstract High copper (Cu) levels in uprooted old vineyard soils may cause toxicity in transplanted young vines, although such toxicity may be reduced by inoculating plants with arbuscular mycorrhizal fungi (AMF). The objective of this study was to evaluate the effects of AMF on the plant growth, chlorophyll contents, mycorrhizal colonization, and Cu and phosphorus (P) absorption in young vines cultivated in a vineyard soil contaminated by Cu. Commercial vineyard soil with high Cu levels was placed in plastic tubes and transplanted with young vines, which were inoculated with six AMF species (Dentiscutata heterogama, Gigaspora gigantea, Acaulospora morrowiae, A. colombiana, Rhizophagus clarus, R. irregularis) and a control treatment on randomized blocks with 12 replicates. After 130 days, the mycorrhizal colonization, root and shoot dry matter (DM), height increment, P and Cu absorption, and chlorophyll contents were evaluated. The height increment, shoot DM and chlorophyll contents were not promoted by AMF, although the root DM was increased by R. clarus and R. irregularis, which had the greatest mycorrhizal colonization and P uptake. AMF increased Cu absorption but decreased its transport to shoots. Thus, AMF species, particularly R. clarus and R. irregularis, contribute to the establishment of young vines exposed to high Cu levels.
