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The Brazilian pepper tree (Schinus terebinthifolius) is an invasive species that requires significant disturbance to eradicate. Previous studies have identified associations between the Brazilian pepper tree and ectomycorrhizal fungi (EMF). However, limited research has explored the connection between disturbance from removal and the effect on EMF. This study investigated the sensitivity of EMF and the broader fungal community to the full and selective removal of the Brazilian pepper tree. During the selective removal of Brazilian pepper tree, we examined the mycorrhizal community of the Arroyo willow (Salix lasiolepis) to assess the influence of the restoration disturbance on native species. We used ITS2 sequencing to identify the EMF present during the restoration. Our expectation was that both removal efforts would reduce the presence of EMF. Contrary to our predictions, full removal increased EMF richness and relative abundance in the soil. As anticipated, selective removal reduced the richness and relative abundance of EMF associated with soil. Selective removal led to a decrease in the richness of EMF in arroyo willow roots with no effect on relative abundance. Moreover, fungal community composition in soil and roots shifted significantly during selective and full removal. However, the community composition of EMF, specifically, remained constant across treatment types. During full removal efforts, the application of organic soil amendments may have contributed to the increase in the diversity and relative abundance of EMF. Selective removal will require additional measures, such as soil amendments, to curtail the loss of EMF. [ABSTRACT FROM AUTHOR]

Sustainable agriculture is based on improving soil microbial activities through new practices including the use of biostimulants such as arbuscular mycorrhizal fungi (AMF). However, many factors, such as plant cultivar, influences the success of mycorrhizal inoculation in field. We investigated the impact of inoculation with Rhizophagus irregularis DAOM 197198 (AGTIV®, Premier Tech) on three potato cultivars (Solanum tuberosum cv. Écrin, Fontane, Manitou ® Desmazières) in two microplots in North of France. In each trial, sampling was carried out (i) at the tuber filling stage to study potato development and nutrition, as well as bacterial and fungal diversity in the roots, and (ii) at maturity to determine tuber yield. Our results showed that inoculation (i) homogenize tuber calibre (ii) significantly increased potato yield and financial income for Manitou plants, (iii) homogenized the phosphate root-to-shoot ratio, and (iv) did not modify neither the taxonomic composition nor the relative abundance of bacteria, fungi and AMF associated with potato roots whatever the potato cultivar. Our results suggest that the positive effects of the inoculation with R. irregularis DAOM 197198 might depend on the potato cultivar, but further investigations are needed to understand the impact of different soils and agricultural systems on inoculation success. [ABSTRACT FROM AUTHOR]

There has been a surge in industries built on the production of arbuscular mycorrhizal (AM) fungal-based inoculants in the past few decades. This is not surprising, given the positive effects of AM fungi on plant growth and nutritional status. However, there is growing concern regarding the quality and efficacy of commercial inoculants. To assess the potential benefits and negative consequences of commercial AM fungal inoculants in grasslands, we conducted a controlled growth chamber study assessing the productivity and AM fungal root colonization of nine grassland plant species grown in grassland soil with or without one of six commercial AM fungal products. Our research showed no evidence of benefit; commercial inoculants never increased native plant biomass, although several inoculants decreased the growth of native species and increased the growth of invasive plant species. In addition, two commercial products contained excessive levels of phosphorus or nitrogen and consistently reduced AM fungal root colonization, indicating an unintentional de-coupling of the symbiosis. As there is little knowledge of the ecological consequences of inoculation with commercial AM fungal products, it is critical for restoration practitioners, scientists, and native plant growers to assess the presence of local AM fungal communities before investing in unnecessary, or possibly detrimental, AM fungal products. [ABSTRACT FROM AUTHOR]

There has been a surge in industries built on the production of arbuscular mycorrhizal (AM) fungal-based inoculants in the past few decades. This is not surprising, given the positive effects of AM fungi on plant growth and nutritional status. However, there is growing concern regarding the quality and efficacy of commercial inoculants. To assess the potential benefits and negative consequences of commercial AM fungal inoculants in grasslands, we conducted a controlled growth chamber study assessing the productivity and AM fungal root colonization of nine grassland plant species grown in grassland soil with or without one of six commercial AM fungal products. Our research showed no evidence of benefit; commercial inoculants never increased native plant biomass, although several inoculants decreased the growth of native species and increased the growth of invasive plant species. In addition, two commercial products contained excessive levels of phosphorus or nitrogen and consistently reduced AM fungal root colonization, indicating an unintentional de-coupling of the symbiosis. As there is little knowledge of the ecological consequences of inoculation with commercial AM fungal products, it is critical for restoration practitioners, scientists, and native plant growers to assess the presence of local AM fungal communities before investing in unnecessary, or possibly detrimental, AM fungal products.

A field trial was conducted in two localities of the Ecuadorian Andes to evaluate potato ( Solanum tuberosum c.v. INIAP - Fripapa) response to inoculation with four commercial products containing the arbuscular mycorrhizal fungus (AMF) strain Rhizophagus irregularis DAOM 197198. In parallel, potato roots were analysed using 454 GS-FLX+ sequencing of c. 800 bp of the nuclear LSU rRNA gene to assess the associated AMF communities. To evaluate inoculation success, sequence reads of R. irregularis on the root samples were compared between inoculated and not inoculated plants by analysing the frequency of occurrence (FO) and relative read abundance (RA). None of the commercial products significantly increased potato yield. Instead, the AMF communities were dominated by an unknown Acaulospora sp. (Sp14) found at high FO and RA in both localities. Rhizophagus irregularis was found in most of the roots of both inoculated and not inoculated plants at both localities. However, its abundance was unexpectedly low indicating poor inoculum establishment. Clearly, many factors have to be taken in consideration for the successful application of AMF-based inoculants. For the Ecuadorian field trials, several causes may explain the lack or poor establishment of R. irregularis such as inoculation technique, agricultural practices, biotic and abiotic conditions and competition with native AMF species. [ABSTRACT FROM AUTHOR]

Aerated lagoons are a main unit operation for wastewater treatment in the paper industry. Many such operations involve inoculation with bacterial formulations in which in situ effectiveness has not been proven; this can be translated into low efficiency in treatment and unnecessary investments. Lack of knowledge of bacterial biodiversity present in a lagoon limits the capacity to exploit the maximum degradation. To overcome such problems, various methods to identify and study these microorganisms have been developed. In this study, a PCR-DGGE analysis was performed to estimate the bacterial diversity and to verify the presence of bacteria present in a commercial inoculum in two aerated lagoons of a pulp and paper effluent. Phylogenetic affiliation of predominant member's correspondent to γ- and β-proteobacteria and Firmicutes were found. The dominant bacteria present in lagoon 2 belonged to the following genus Microbacterium sp. Rhodocyclaceae sp., Eubacterium sp. and B. subtilis. In lagoon 1 the dominant genus included Microbacterium sp., Rhodocyclaceae sp. Tepidimonas sp., Acetanaerobacterium sp., and Flavobacteria sp. The two characterized lagoons were not similar to the commercial inoculum. In addition, nondominant bacteria (less relative intensity) were composed mostly of bacteria of the commercial inoculum. [ABSTRACT FROM AUTHOR]

We tested the hypothesis that field applications of arbuscular mycorrhizal (AM) inocula would increase root colonization and plant performance in a coastal sage scrub (CSS) restoration project in Southern California. We applied commercial or native inocula (from nearby reference shrublands) as we seeded plots with native shrubs, forbs, and grasses. A control treatment was seeded but received no inocula. After 6 months, AM root colonization did not differ significantly among treatments. Likewise, neither inoculum type significantly altered shoot biomass of native shrubs and forbs at 6 months, or density of adult and seedling shrubs at 10 months. Notably, shoot height at 10 months was shorter in plots treated with commercial inoculum compared with the controls. In addition, flower and flower bud production by Salvia columbariae did not significantly respond to either inoculum type. Altogether, we found no evidence that AM inoculation improved restoration success in our CSS system. [ABSTRACT FROM AUTHOR]

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Abstract: Inoculated fermentations are practiced in most wine regions of the world. This type of fermentation involves adding a commercial Saccharomyces cerevisiae strain as an inoculant. It is often assumed that the inoculant maintains dominance throughout the fermentation; however, sometimes commercial or indigenous yeasts, which were not intentionally added, end up as the dominant yeast in the winery fermentation. The aim of this study was to compare implantation/persistence of inoculants among three Canadian wineries (Quails' Gate, Cedar Creek, and Road 13 wineries). In 2010, three inoculated fermentation tanks at each of three wineries were sampled at four stages of fermentation (pre-inoculation, early, mid, and end). In addition, results from the end stage of fermentation, from two of the three wineries, were compared among different vintages (resulting in a 4-year comparison at Quails' Gate winery and a 2-year comparison at Cedar Creek winery). Strains of S. cerevisiae were discriminated by microsatellite analysis and identified using commercial microsatellite databases, whereas DNA sequencing was used to identify non-Saccharomyces. The percent implantation/persistence of the inoculum was significantly lower at Quails' Gate and Cedar Creek wineries as compared with the Road 13 winery in the 2010 vintage. Relatively low persistence of the inoculum at Quails' Gate winery was also found in the 2009 vintage, but low values were not found at Quails' Gate winery in 2011 and 2012 or at Cedar Creek winery in 2012. In all tanks having <80% relative abundance of the inoculant, the commercial strain (Lalvin ICV-D254®/Fermol® Premier Cru) was the dominant or co-dominant yeast. Our findings highlight year-to-year variation in inoculum implantation/persistence and the idea that unless strain typing of S. cerevisiae is conducted at the winery, there are no obvious fermentation factors that would indicate a relatively low inoculum implantation/persistence. [Copyright &y& Elsevier]

Abstract: A comparative study was performed on compost extracts prepared from cattle rumen content composted for three and nine months, nine month old compost inoculated with a Nutri-Life 4/20™ inoculum, and two commercial preparations (LivingSoil™ and Nutri-Life 4/20™), all incubated for 48h. Nutri-Life 4/20™ had the highest concentrations of and K+–K, while rumen compost extract had higher humic and fulvic acids concentration. The bacterial and fungal community level functional diversity of three month old compost extract and of LivingSoil™, assessed with Biolog™, were higher than that of nine month old rumen compost extract, with or without Nutri-Life 4/20™ inoculum, or Nutri-Life 4/20™. No difference in fungal diversity was observed between treatments, as indicated by Denaturing Gradient Gel Electrophoresis (DGGE) analysis, however, bacterial diversity was higher in all compost extracts and LivingSoil™ compared to the Nutri-Life 4/20™. Criteria for judging the quality of a microbially enhanced extract are discussed. [Copyright &y& Elsevier]

Arbuscular mycorrhizal fungi (AMF) may play an important role in ecological succession, but few studies have documented the effectiveness of mycorrhizal inoculation at restoration/reclamation sites. At a roadside prairie restoration in Shakopee, Minnesota, we compared AMF root colonization and resulting vegetative cover among four inoculation treatments. After 15 mo of growth, we found that AMF colonization was high in all treatments but was significantly higher in treatments that received AMF inoculum propagated from a local prairie site or commercially available inoculum than the uninoculated control. For the prairie inoculum, this increase in colonization occurred whether the inoculum was applied with seeds in furrows or broadcast with seeds on the soil surface. However, increased colonization did not discernibly affect the restored vegetation; neither total vegetative cover nor the proportion "desired" prairie vegetation differed among inoculation treatments. By the end of the third growing season (27 mo alter planting) there were no longer differences in AMF colonization among the inoculation treatments nor were there differences in vegetative cover. It is likely that natural recolonization of the plots by remnant AMF populations at the site limited the duration of the inoculation effect. This natural recolonization, in combination with relatively high soil phosphorus levels, likely rendered inoculation unnecessary. In contrast to previous published studies of AMF inoculation in landscape restorations, this study shows that AMF inoculation may not be warranted under some circumstanees. [ABSTRACT FROM AUTHOR]

Reestablishing native perennial plants and reducing invasive species are pivotal for many ecological restoration projects. The interactions among plant species, arbuscular mycorrhizal fungi, and soil P availability may be critical determinants of the success of native and non-native plants in restoration and species invasions. Here we assessed mycorrhizal responsiveness for three late-successional and three early-successional plant species native to Rocky Mountain National Park and for the non-native Downy brome, cheatgrass ( Bromus tectorum L.) using field soil and commercial inoculum. Factorial greenhouse experiments were conducted to compare biomass of plant species with and without field soil and commercial inoculum treatments along a phosphorus (P) gradient, which ranged from ambient field levels to 12% of field levels, using dilutions of native soils. The two field soil inoculum treatments resulted in significant biomass differences for all species studied. Late-successional species responded positively to field inoculum, whereas early-successional species responded negatively. The two commercial inocula had low colonization rates (14 of 166 inoculated plants). The commercial inocula substrates had significant treatment effects on five of seven species included in the study in the apparent absence of mycorrhizal symbiosis. Soil P levels influenced mycorrhizal responsiveness in only one species, Smooth blue aster ( Aster laevis L.). Our results show that, at least for the species studied here, locally collected field inoculum is the best choice for reestablishment of late-successional native plant species. [ABSTRACT FROM AUTHOR]

Vegetative inoculum of Pisolithus tinctorius (Pt) produced by Sylvan Spawn Laboratories (C:N 50) and by research methods (IMRD), spore-encapsulated seeds, spore pellets, and sprayed spores were compared for efficacy in forming Pt ectomycorrhizae on pines in operational bare-root nurseries in South Carolina, Florida, and Indiana and in microplots and containers in Georgia. Two rates of application (0.33 and 0.16 liter/m of soil) of both sources of vegetative inoculum were similar in effect and formed abundant Pt ectomycorrhizae (Pt index > 50) and fruit bodies in all studies. Spore treatments formed consistently fewer Pt ectomycorrhizae than vegetative inoculum. The most effective spore treatment was spore encapsulated seeds. These results indicate that at a bed density of 270 seedlings/m, 0.6 to 0.7 liter of vegetative inoculum is needed to obtain Pt indices > 50 on 1,000 pine seedlings. [ABSTRACT FROM AUTHOR]