Shannon’s index is affected by the species number and their equit

Shannon’s index is affected by the selleck chemical species number and their equitability, check details or evenness. A greater number of species and an even distribution of abundances result in an elevated Shannon’s diversity index. The maximum Shannon’s diversity

index for a sample indicates that all species are nearly equally abundant. The Gini-Simpson’s diversity index is measured as the probability that two individuals randomly selected from a sample belong to the same species, with a range from 0 to 1. Value of 0 indicates lack of diversity, i.e., one dominant species or taxon in the community, and 1 suggests that the community contains an infinite number of taxa with all taxa present equally. Before alpha-diversity indices were calculated, multiple rarefactions were performed with our own Perl scripts. All fungal reads from each marker were resampled starting at the depth of 1,000 reads, stepping up to 385,000 reads with increments of 1,000, and ten replicates were done at each sampling depth. For illustrating fungal find more diversities, taxonomic

relationships of all detected fungal genera were converted to the Newick format and uploaded to the web-based tool Interactive Tree Of Life v2.2 (Letunic and Bork 2011), and the taxonomic trees for each barcode and for all barcodes combined were generated. Estimation of the taxon abundance based on copy numbers of PCR-amplified DNA reads for a mixture of homologous genes in a multi-template PCR can be biased due to the differences in the primer binding energy to the target (Kanagawa 2003). Consequently, the taxon diversity and proportion of any given operational taxonomic

unit (OTU) in the fungal community are expected to differ when using different sets of DNA barcodes. In this study, the percentage of reads for a taxon was calculated by dividing the total reads of fungi generated by individual barcodes (Table S3). Because of the bias in mafosfamide the taxonomic assignations of mtATP6, that was restricted to the class Agaricomycetes except for six reads, we excluded mtATP6 from estimating species abundance with multiple barcodes. The percentage of reads for each of the genera generated from five barcodes (ITS1/2, ITS3/4, nrLSU-LR, nrLSU-U and mtLSU) was then transformed to a rank score based on the abundance of each genus in the community using the formula 20 − 19 (rank − 1)/(N − 1). The ranks (1, 2, 3…to N) represent the order of abundance (percentage of reads) for all taxa; thus, a taxon with rank 1 is most abundant and receives the highest rank score (20). When several taxa have the same abundance, the highest rank of these taxa was used as representative. The highest rank score was set to 20 for a given taxon having the highest number of reads (rank = 1), and the lowest rank score was set to 1 for a given taxon having lowest number of reads (rank = N).

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