Sampling effort curves for native vegetation soil, <i>Ricinus communis</i> soil and <i>Jatropa curcas</i> soil.

<p>The sample order was randomized by 100 replications in EstimateS, version 8.0 <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0034887#pone.0034887-Colwell1" target="_blank">[56]</a>.</p

Pearson's coefficients of correlation and significance level between the soil parameters measured, the root length colonised and the AMF diversity (n = 5).

<p>Pearson's coefficients of correlation and significance level between the soil parameters measured, the root length colonised and the AMF diversity (n = 5).</p

Number of clones detected for each fungal type in the native vegetation soil and <i>Ricinus communis</i> and <i>Jatropa curcas</i> soil (<i>n</i> = 5).

<p>Number of clones detected for each fungal type in the native vegetation soil and <i>Ricinus communis</i> and <i>Jatropa curcas</i> soil (<i>n</i> = 5).</p

Canonical correspondence analysis (CCA) of the different AMF sequence types and soil properties detected in the three soils studied.

<p>The eigenvalues of the first and second axes in the two-dimensional ordination diagrams are as follows: CCA1: 0.59 and CCA2: 0.55. C: native vegetation soil, R: <i>Ricinus communis</i> soil, J: <i>Jatropa curcas</i> soil, MBC:.microbial biomass C, CRL: colonized root length, AS: aggregate stability, OC: organic C, N: total N, EC: electrical conductivity.</p

Biological, chemical and physical properties of native vegetation soil and <i>Ricinus communis</i> and <i>Jatropa curcas</i> soil (n = 5).

<p>Degree of AM fungal colonization in roots of <i>R. communis</i>, <i>J. curcas</i> seedlings and native vegetation soil.</p><p>MBC: microbial biomass C; Means ± standard errors; Values in row followed by the same letter do not differ significantly (<i>P</i><0.05) as determined by the LSD test.</p

Phylogenetic tree of AMF sequences isolated from the <i>Prunus persica</i> roots under different treatments (T1: Combination of organic and inorganic fertilization and integrated pest management; T2: Inorganic fertilization and integrated pest management; T3: Inorganic fertilization and chemical pest control; T4: Combination of organic and inorganic fertilization and chemical pest control), reference sequences corresponding to the closest matches from GeneBank as well as sequences from cultured AMF taxa including representatives of the major taxonomical groups.

<p>Numbers above branches indicate the bootstrap values determined for Neighbour-Joining (NJ) analysis; bold numbers below branches indicate the bootstrap values of the maximum likelihood analysis. Sequences are labelled with the number of treatment from which they were obtained (T1, T2, T3, T4) and the clone identity number, Group identifiers (for example Glo 1) are AM fungal sequences types found in our study. Since identical sequences were detected, the clones producing the same sequence for each treatment were represented once in the alignment for clarity (Table S1 in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0088454#pone.0088454.s001" target="_blank">File S1</a> material show a detailed description of the total number of clones of each AMF phylotype that were recovered from each treatment).</p

<i>Prunus persica</i> Crop Management Differentially Promotes Arbuscular Mycorrhizal Fungi Diversity in a Tropical Agro-Ecosystem

<div><p>Due to the important role of arbuscular mycorrhizal fungi (AMF) in ecosystem functioning, determination of the effect of management practices on the AMF diversity in agricultural soils is essential for the sustainability of these agro-ecosystems. The objective of this study was to compare the AMF diversity in <i>Prunus persica</i> roots under two types of fertilisation (inorganic, with or without manure) combined with integrated or chemical pest management in a Venezuelan agro-ecosystem. The AM fungal small-subunit (SSU) rRNA genes were subjected to PCR, cloning, sequencing and phylogenetic analyses. Twenty-one different phylotypes were identified: 15 belonged to the genus <i>Glomus,</i> one to <i>Claroideoglomus</i>, two to <i>Paraglomus</i>, one to <i>Acaulospora,</i> one to <i>Scutellospora</i> and one to <i>Archaeospora.</i> The distribution of the AMF community composition differed as a consequence of the treatment effects. The treatment combining organic and inorganic fertilisation with chemical pest control had the highest AMF richness and the treatment combining inorganic fertilisation with chemical pest had the lowest. The real causes and effects of these differences in the AMF community are very difficult to establish, since the crop management regimes tested were composed of several interacting factors. In conclusion, the crop management practices can exert a significant influence on the populations of AMF. The treatment combining organic and inorganic fertilisation with chemical pest control appears to be the most suitable agricultural management strategy with respect to improving the AMF diversity in this crop under tropical conditions, and thus for maintaining the agricultural and environmental sustainability of this agro-ecosystem.</p></div

Sampling effort curves for <i>Prunus persica</i> roots under different treatments analysed.

<p>T1: Combination of organic and inorganic fertilization and integrated pest management; T2: Inorganic fertilization and integrated pest management; T3: Inorganic fertilization and chemical pest control; T4: Combination of organic and inorganic fertilization and chemical pest control. The number of clones for each AMF phylotypes in each root sample was used to construct the sampling effort curves (with 95% confidence intervals) using the software EstimateS 8.00 (Colwell, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0088454#pone.0088454-Colwell1" target="_blank">[33]</a>). The sample order was randomized by 100 replications.</p

Canonical Correspondence analysis (CCA) of the AM fungal community composition found in the roots of <i>P. persica</i> under different treatments (T1: Combination of organic and inorganic fertilization and integrated pest management; T2: Inorganic fertilization and integrated pest management; T3: Inorganic fertilization and chemical pest control; T4: Combination of organic and inorganic fertilization and chemical pest control).

<p>Full triangles represent the treatments and the open triangles the AMF phylotypes. Open circles represent the AMF phylotypes exclusively found in individual treatments.</p

Bar plot showing the number of clones detected for each AM fungal sequence type in the soil irrigated with fresh water (FW) and treated wastewater (WW) 43 years after establishment.

<p>Bar plot showing the number of clones detected for each AM fungal sequence type in the soil irrigated with fresh water (FW) and treated wastewater (WW) 43 years after establishment.</p