The mosaic of habitats in the high-altitude Brazilian rupestrian fields is a hotspot for arbuscular mycorrhizal fungi.

The high diversity in rupestrian field vegetation has been attributed to the mosaic of environments formed by several soil classes, rugged relief and microclimatic variation. Although advances in the knowledge of some biological areas in rupestrian fields have been made, little is known about the relevance of soil microorganisms and their relationships with the vegetation. Symbiosis with arbuscular mycorrhizal fungi (AMF) is one of the most studied interactions between microorganisms and plants, because they are ubiquitous and contribute to the sustainability of ecosystems. This study aimed to investigate the occurrence and diversity of AMF species and to evaluate their relationship with soil physicochemical attributes and plant diversity in different habitats of the rupestrian fields from the Cadeia do Espinhaço, Serra do Cipó, Brazil. These rupestrian fields were delimited into five distinct habitats: rock outcrop, quartz gravel fields, sandy bogs, peat bogs and the Cerrado. Forty-nine AMF species were identified as belonging to nine families and twelve genera. Among them, Acaulospora colossica and Pacispora dominikii were found for the first time in Brazil. The results of this study suggest that the diversity of AMF is related to the heterogeneity of habitats and that the soil texture (coarse sand, gravel and silt) is better related to the structure of these fungi communities than to the soil chemical attributes. Plant species richness was related to AMF richness only in the quartz gravel field, rocky outcrop, and sandy bog habitats. Considering these habitats constitute one of the most menaced ecosystems on the planet, our survey provides information to improve knowledge about rupestrian field biodiversity, thus supporting policy actions for its conservation and preservation

Percevejos associados a cultivos de mangueira no Submédio do Vale do São Francisco.

O presente estudo buscou identificar as espécies de percevejos associadas às diferentes estruturas da mangueira

Hemiptera Linnaeus, 1758.

A ordem Hemiptera é a mais diversa entre os insetos hemimetábolos. Recebem vários nomes populares, de acordo com a subordem. São conhecidas mais de 106 mil espécies em todo mundo, assim distribuídas nas quatro subordens reconhecidas atualmente: cerca de 18 mil em Sternorrhyncha, 43 mil em Auchenorrhyncha e mais de 45 mil em Heteroptera; Coleorrhyncha, ausente no Brasil, contém somente 37 espécies. A ordem compreende cerca de 10% de todas as espécies de insetos conhecidas, com uma estimativa para cerca de 150 mil espécies. No Brasil, há cerca de 1.100 espécies conhecidas de Sternorrhyncha, cerca de 3.900 de Auchenorrhyncha e cerca de 5.700 de Heteroptera, com uma estimativa para a existência de cerca de 30 mil espécies para toda a ordem no país

Soil–strain compatibility: the key to effective use of arbuscular mycorrhizal inoculants?

Consistency of response to arbuscular mycorrhizal (AM) inoculation is required for efficient use of AM fungi in plant production. Here, we found that the response triggered in plants by an AM strain depends on the properties of the soil where it is introduced. Two data sets from 130 different experiments assessing the outcome of a total of 548 replicated single inoculation trials conducted either in soils with a history of (1) high input agriculture (HIA; 343 replicated trials) or (2) in more pristine soils from coffee plantations (CA; 205 replicated trials) were examined. Plant response to inoculation with different AM strains in CA soils planted with coffee was related to soil properties associated with soil types. The strains Glomus fasciculatum-like and Glomus etunicatum-like were particularly performant in soil relatively rich in nutrients and organic matter. Paraglomus occultum and Glomus mosseae-like performed best in relatively poor soils, and G. mosseae and Glomus manihotis did best in soils of medium fertility. Acaulospora scrobiculata, Diversispora spurca, G. mosseae-like, G. mosseae and P. occultum stimulated coffee growth best in Chromic, Eutric Alluvial Cambisol, G. fasciculatum-like and G. etunicatum-like in Calcaric Cambisol and G. manihotis, in Chromic, Eutric Cambisols. Acaulospora scrobiculata and Diversispora spurca strains performed best in Chromic Alisols and Rodic Ferralsols. There was no significant relationship between plant response to AM fungal strains and soil properties in the HIA soil data set, may be due to variation induced by the use of different host plant species and to modification of soil properties by a history of intensive production. Consideration of the performance of AM fungal strains in target soil environments may well be the key for efficient management of the AM symbiosis in plant production

Arbuscular mycorrhizal fungi (AMF) root colonization dynamics of Molinia caerulea (L.) Moench. in grasslands and post-industrial sites

This is an accepted manuscript of an article published by Elsevier in Ecological Engineering on 05/08/2016, available online: https://doi-org.ezproxy.wlv.ac.uk/10.1016/j.ecoleng.2016.06.029 The accepted version of the publication may differ from the final published version.The aims of this studies were: (i) to examine the influence of heavy metal content (Zn, Cd, Pb, Fe, Cu) and other physico-chemical soil parameters on the level of root colonization of Molinia caerulea and (ii) to relate root colonisation parameters and soil variables to Molinia caerulea abundance in two contrasting habitats (grasslands and heavy metal contaminated sites). The sites differ significantly in terms of bio-available heavy metal contents, particularly Zn (34 times more than grasslands), soil texture, CaCO3, organic matter (LOI%), Mg and nitrate content. Principal Component Analysis showed the strong negative correlations between frequency of mycorrhization (F), arbuscular abundance (A%) and intensity of root cortex colonisation (M%) and concentration of bio-available Zn and Cd. Moreover, no positive correlation between root colonization of Molinia and its abundance was found. The frequency of mycorrhization of root fragments (F%) was only slightly different between these two habitats, whereas the intensity of root cortex colonisation (M%) and relative arbuscular abundance (A%) were significantly lower (3 and 4 times respectively) on the post-industrial sites. The bioavailable Zn content in the substratum of post-industrial sites was strongly negatively correlated with species richness, Shannon diversity index and Evenness. In contrast, these relationships were not statistically significant in grasslands. Based on obtained results we could draw a model of possible relationships between root colonization of Molinia, HM content and Molinia abundance on grasslands and post-industrial sites. Bioavailable Zn content in the soil is a one of main factors influencing the Molinia community diversity. In the grasslands, lower amounts of bioavailable Zn, resulted in higher species richness (R) and species diversity (H) which in turn lead to higher root colonization. On the other hand, on the post-industrial sites, the elevated bioavailable Zn content strongly decreases the plant species richness (R) and species diversity (H) and this caused the decline in root colonization parameters. The low species richness on Zn-polluted sites allowed Molinia to reach higher abundance since the competition with other species is reduced