Search Results (170)

New Zealand’s only tea (Camellia sinensis) plantation supplies a niche market for organically produced high value tea but faces challenges from climatic conditions and the decision to use only organic production methods. Fungi from the genus Trichoderma have been commercialised in New Zealand and elsewhere as disease-suppressing and plant growth-promoting agents. However, the potential benefits of using Trichoderma as a microbial biostimulant for tea cultivation have not been investigated in New Zealand. The ability of T. atroviride application to stimulate tea plant growth at a tea plantation was investigated over one year of production. The study involved foliar application of the biostimulant either once, twice or three times, one month apart, using 12 g of a commercially formulated spore mixture of four strains of T. atroviride per 5 m² of experimental plots. Treatment with T. atroviride significantly increased tea yield by between 17% and 28% compared to the control over the harvesting season, but there were no statistically significant yield differences among the number of applications. The foliar applied T. atroviride was not detected in the soil or root samples six months after application, in either a soil metabarcoding analysis or on re-isolation media. This was likely due to the dense tea foliage and ground cover under the tea plants which impeded its movement to the soil. While the specific nature of T. atroviride interaction with perennial crops like tea is not known, in this trial it appeared to have remained on the phyllosphere and provided biostimulation without reaching the soil. Full article

This study evaluated the efficiency of arbuscular mycorrhizal fungi (AMF) in promoting the growth, yield, protein, and phytochemical contents of Glycine max cv. Morkhor 60. A completely randomized pot experiment was conducted for 90 days in non-sterile soil with nine replications. Three AMF species were tested and compared with two non-mycorrhizal controls, with and without NPK fertilizer. All AMF treatments enhanced plant growth, photosynthetic rate, and water-use efficiency compared with the unfertilized control. Inoculation with Acaulospora dilatata KKU-SK202 produced the highest pod number and increased 100-seed weight by 27.00% and 4.13% over the non-inoculated and NPK treatments, respectively. Gigaspora margarita KKU-SK210 yielded the highest total protein and phenolic contents, while A. dilatata KKU-SK401 showed the highest antioxidant activity (72.09%). Metabarcoding analysis revealed that AMF inoculation reduced root colonization by pathogenic fungi, with G. margarita KKU-SK210 and A. dilatata KKU-SK202 being the most effective. These results suggest that AMF inoculation can enhance soybean productivity and seed quality while reducing chemical fertilizer dependency and pathogenic fungal incidence. Full article

Interactions with plants are an important aspect of mosquito vector biology and ecology because mosquitoes often use plants as nutritional resources. Plant DNA metabarcoding is a recent approach to address this topic. Culex quinquefasciatus is a vector of several important pathogens in Florida and is subject to significant control efforts, but no studies to date have explored what plants they may feed on. We addressed this by conducting a statewide collection of Cx. quinquefasciatus from six Florida counties and subjected them to plant DNA metabarcoding and cross-referenced the identified plants to a Florida state plant voucher database for each sampled county. A total of 30 families and 47 genera were identified. Plants included many that are cultivated and non-cultivated in Florida, including backyard garden produce, grasses, and some invasive species. Concurrence of plant families and genera was generally high in the respective sampled counties based on available plant vouchers. These data provide the first statewide survey of plants associated with Cx. quinquefasciatus in Florida. This information serves as an important basis for confirming plant taxa that are important to Cx. quinquefasciatus, which could translate to the development of better control strategies and tools. Full article

Soil degradation and climate-driven stress increasingly compromise crop performance by disrupting microbial communities and weakening soil biological functions. Microbial consortia such as Effective Microorganisms (EM) are widely adopted as nature-based solutions to enhance soil health and plant productivity, yet it remains unclear whether their biostimulant effects arise primarily from microbial activity or from the metabolites they release. This study aimed to disentangle these contributions by comparing the effects of EM and its cell-free extract (EM Extract) on zucchini (Cucurbita pepo L.), grown under controlled conditions. Growth parameters and pigment composition were quantified through morphological and spectrophotometric analyses, while soil microbial communities and metabolic profiles were characterized using metabarcoding and high-resolution FTIR-based soil metabolomics. Both EM and EM-derived cell-free extracts significantly enhanced zucchini growth, increasing plant height, biomass, chlorophyll content and root development. Cultural-based microbial analyses showed complementary shifts in rhizosphere communities, yet no major taxonomic differences were detected. Consistently, both treatments induced similar metabolomic changes in bulk and rhizosphere soils, resulting in a shared functional state shaped by plant inputs. These results suggest EM extract as a stable and effective alternative to live microbial inoculants for sustainable crop bio stimulation. Full article

The diet of wild boars (Sus scrofa) is highly diverse, consisting of both plant and animal materials, and their foraging behavior varies seasonally. However, limited research has investigated the composition of macrofungi in the diet of these omnivorous mammals, and relevant information remains scarce. This study aimed to assess the diversity of plant, animal, and macrofungal components in the diet of wild boars and to evaluate seasonal variations in Bukhansan National Park, Republic of Korea. Fecal samples were collected across different seasons, and DNA metabarcoding was applied to compare the taxonomic composition of dietary items. The results revealed that the wild boar diet included 54 plant genera, 9 animal genera, and 22 macrofungal genera. Among the plants, Pueraria, Quercus, and Ipomoea were the most dominant, with relative abundances of 21.3%, 18.3%, and 16.4%, respectively. The primary animal taxa consisted of Neomyia (54.7%) and Didea (39.4%), while Rhizopogon accounted for 95.3% of the macrofungal sequences detected. Overall, the study demonstrated clear seasonal variation in the diet of wild boars, reflecting their remarkable adaptability to changing environmental conditions. Full article

Chemical fungicides play a key role in protecting crops, but their use can result in environmental problems. We tested a novel fungicide, composed of endophytic microorganisms, for its effect on wheat yield, grain quality, plant development, and the rhizosphere microbiome, assessed by 16S and ITS metabarcoding. The fungicide increased the grain yield, the effect being similar to a well-known commercial bacterial fungicide, without affecting its quality. Ascomycota, Zygomycota and Mucoromycota together comprised 80% of the mycobiome. Mucoromycota/Mucoromycetes/Rhizopodaceae/Rhizopus arrhizus were significantly decreased. The dominant (≥10%) bacterial phyla were Pseudomonadota, Acidobacteriota, Bacteroidota and Actinomycetota, but their fungicide-related differences were small or random. Different modes of fungicide application (seeds only, seeds plus one or two foliar applications) had no effect on wheat characteristics. Neither of the fungicide’s agents (Raoultella ornithinolytica and Pantoea allii) were found in the rhizosphere. The changes in the mycobiome seemed more pronounced than in the bacteriobiome. The proposed preparation is concluded to have good prospects as a fungicide. However, the low species/strain resolution of the DNA metabarcoding did not allow us to fully interpret shifts in the microbiome diversity, both agronomically and environmentally. These aspects need more comprehensive investigation, using methodology with higher species resolution. Full article

Antarctica harbors some of the most extreme ecosystems on earth, where only two vascular plants persist. The native grass Deschampsia antarctica provides a model for plant–microbe interactions under intense abiotic stress. We present the first multi-compartmental and multi-kingdom characterization of bacterial and fungal communities associated with D. antarctica across three South Shetland Islands. Metabarcoding revealed strong compartmentalization: the rhizosphere displayed the highest richness and complex bacterial–fungal networks; the root endosphere showed intermediate diversity with keystone taxa such as Rhizobiales and Streptomyces; and the leaf endosphere was simplified, dominated by stress-tolerant taxa including Pseudomonas and Helotiales. Despite marked soil heterogeneity, phosphorus enrichment at Admiralty Bay, base cations at Coppermine Cove, and iron at Byers Peninsula, a conserved core (20 bacterial and 5 fungal genera) persisted, mainly cold-adapted saprotrophs and plant-associated taxa. Fungal assemblages were more responsive to soil chemistry, with site-specific enrichments such as Zymoseptoria and Herpotrichia. Overall, D. antarctica holobionts exhibited a dual strategy: conserved microbial backbones confer stability, while localized assemblages shaped by soil chemistry and geography enhance adaptability. Together, these findings provide one of the most integrative characterizations of the D. antarctica holobiont to date, revealing how conserved and adaptive microbial components support plant resilience under extreme Antarctic conditions and offering valuable insights for predicting biological responses to ongoing climate change. Full article

The presence of substantial amounts of heavy metals in the environment can result in various significant ecological issues and human health risks. Currently, bioremediation employing microorganisms is garnering significant interest due to its effectiveness. The present investigation aimed to isolate actinobacterial strains from an Italian mine and to characterise them for heavy metals resistance and plant growth-promoting characteristics. The different samples were processed for DNA extraction and 16S rRNA gene metabarcoding to investigate the bacteria and archaea communities. Cultivable microbiota were isolated and evaluated for heavy metals tolerance and different PGP traits. The most pertinent strains were tested for compatibility, merged into a consortium, and tested on Lemna minor L. Metabarcoding analysis revealed that amplicon sequence variants (ASVs) at the phylum level were mostly assigned to proteobacteria and bacteroidota. Uncultured and unknown taxa were the most prevalent in the samples at the genus level. A total of ten strains were obtained from the culture-dependent approach exhibiting interesting heavy metals tolerance and plant growth-promoting traits. The best strains (MTW 1 and MTW 5) were selected and further characterised by 16S barcoding. These strains were identified as Streptomyces atratus (99.57% identity). An in planta experiment showed that the metal-tolerant consortium MTW 1-5 improved plant physiology by significantly optimising plant growth and tolerance to heavy metals. The experiment conducted provided evidence for the possibility of using actinobacteria as bioaugmentation agents to improve the phytoextraction abilities of L. minor. Full article

The Nearctic leafhopper Scaphoideus titanus is the primary vector of Flavescence Dorée, a severe grapevine disease in Europe. This insect can complete its life cycle on both cultivated Vitis vinifera and American Vitis species, including rootstock-derived plants that have gone wild. While the movement of S. titanus between wild and cultivated vines is well documented, its biological implications remain unclear, particularly regarding the role of the insect-associated microbiome. In this study, we investigated how rearing S. titanus nymphs on different host plants, including American Vitis and several V. vinifera cultivars, affects its bacterial community. 16S rRNA metabarcoding revealed that the bacterial microbiome was dominated by two obligate symbionts, namely ‘Candidatus Karelsulcia’ and ‘Candidatus Cardinium’, with moderate but significant differences in microbial diversity among host plants and developmental stages. When these dominant symbionts were excluded, variability in the remaining bacterial community increased, indicating a modulation of minor taxa according to the plant offered. These findings suggest that host plant species influence the microbiome structure, potentially affecting the insect performance and the microbial exchange between wild and cultivated vines in the field, contributing to disease dynamics. Full article

Quantifying sex-specific dietary differences in small mammals reveals the internal resource allocation mechanisms within a species and provides new insights for ecosystem management and conservation practices. The plateau pika (Ochotona curzoniae) and plateau zokor (Eospalax baileyi) are dominant small mammals that exhibit distinct lifestyles and social structures on the Qinghai-Tibetan Plateau. Despite the fact that the diets of both species have been extensively studied, sex-specific dietary differences have rarely been investigated. This study employed DNA metabarcoding combined with a self-constructed plant DNA barcode database to analyze the diet composition and trophic niche of male and female plateau pika and plateau zokor during the growing season. The results showed that male and female plateau pika consumed 39 and 37 plant species, respectively, and male and female plateau zokor consumed 38 and 39 plant species, respectively. With respect to the plateau pika, males showed a significantly higher intake of Phlomoides umbrosa than females (p < 0.05), whereas females consumed a significantly greater proportion of tuberous plants (p < 0.05). Females also exhibited a significantly greater dietary diversity and trophic niche breadth than males. But there was no significant difference in dietary diversity and trophic niche breadth between the sexes in the plateau zokor. In conclusion, our results show that dietary differences between males and females depend on each species’ lifestyle. Social, surface-living pikas show apparent sex-based differences, while solitary, underground-living zokors do not. Full article

Microorganisms are fundamental drivers of soil productivity, mediating nutrient cycling and pathogen suppression. In this study, we evaluated changes in the fungal community in the soil of barley (Hordeum vulgare L.) in a field experiment involving the application of a consortium of Paenibacillus pabuli, Priestia megaterium, Pseudomonas koreensis, and Pseudomonas orientalis. Seed pretreatment and seed pretreatment followed by rhizosphere drenching at different growth stages were implemented. Regarding fungal communities in bulk soil, the rhizospheres of untreated and treated plants were characterized based on full-length ribosomal RNA gene (18S-5.8S-28S) metabarcoding sequencing. Despite the compositional shifts, no statistical differences were observed among the alpha diversity metrics. Seed treatment resulted in long-term, targeted suppression of Fusarium graminearum, Fusarium fujikuroi, Fusarium musae, and Fusarium verticillioides from the booting through flowering and dough development stages, outperforming seed pretreatment followed by rhizosphere drenching. A low-modularity network was observed in the rhizosphere of untreated plants. Seed treatment fostered a highly interconnected and uniform network with low hub-betweenness scores. Rhizosphere drenching of pretreated seeds shifted the network topology toward higher hub-betweenness scores, reducing their connectivity by up to 10% in the rhizosphere and bulk soil. These findings provide a framework for optimizing the soil ecosystem for sustainable agriculture. Full article

The grapevine microbiome is shaped by a complex interplay of biotic and abiotic factors, affecting microbial community structure and plant health. This study investigates the diversity, composition, and dynamics of fungal communities associated with grapevine (Vitis vinifera) and neighboring cultivated plants, as well as plants from semi-natural vegetation, including pear (Pyrus communis), apricot (Prunus armeniaca), dogrose (Rosa canina), and blackthorn (Prunus spinosa), in a landscape-level habitat matrix. Using metabarcoding techniques, fungal communities from leaves and woody tissues of grapevine and neighboring plants were analyzed over a growing season. Fungal richness and abundance differed significantly among host plants, with woody tissues exhibiting higher diversity. Host plant identity was the primary factor shaping wood-associated fungal communities (15.7% of explained variance), whereas sampling time dominated in leaves (16.3%), with sampling site having a weaker effect in both cases. Pathogenic fungi associated with grapevine trunk diseases, such as Diaporthe, Eutypa, and Phaeomoniella, were identified across grapevine and neighboring plants, suggesting that multiple hosts may act as reservoirs for fungal inoculum. These findings highlight the complex interactions between fungal communities, host plants, and environmental factors, underscoring the need for landscape-level approaches to plant protection that account for both cultivated and surrounding ecosystems. Full article

The Mongolian wild ass (Equus hemionus hemionus) is a flagship species of the desert-steppe ecosystem in Asia, and understanding its strategies for coping with cold environments is vital for both revealing its survival mechanisms and informing conservation efforts. In this study, we employed metagenomic sequencing to characterize the composition and functional potential of the gut microbiota, and applied DNA metabarcoding of the chloroplast trnL (UAA) g–h fragment to analyze dietary composition, aiming to reveal seasonal variations and the interplay between dietary plant composition and gut microbial communities. In the cold season, Bacteroidota and Euryarchaeota were significantly enriched, suggesting enhanced fiber degradation and energy extraction from low-quality forage. Moreover, genera such as Bacteroides and Alistipes were also significantly enriched and associated with short-chain fatty acid (SCFA) metabolism, bile acid tolerance, and immune modulation. In the cold season, higher Simpson index values and tighter principal coordinates analysis (PCoA) clustering indicated a more diverse and stable microbiota under harsh environmental conditions, which may represent an important microecological strategy for the host to cope with extreme environments. Functional predictions based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) further indicated upregulation of metabolic and signaling pathways, including ABC transporters, two-component systems, and quorum sensing, suggesting multi-level microbial responses to low temperatures and nutritional stress. trnL-based plant composition analysis indicated seasonal shifts, with Tamaricaceae detected more in the warm season and Poaceae, Chenopodiaceae, and Amaryllidaceae detected more in the cold season. Correlation analyses revealed that dominant microbial phyla were associated with the degradation of fiber, polysaccharides, and plant secondary metabolites, which may help maintain host energy and metabolic homeostasis. Despite the limited sample size and cross-sectional design, our findings highlight that gut microbial composition and structure may be important for host adaptation to cold environments and may also serve as a useful reference for future studies on the adaptive mechanisms and conservation strategies of endangered herbivores, including the Mongolian wild ass. Full article

Understanding the soil fungal community in vineyards sheds light on the interactions between plants and their associated microorganisms. For example, identifying arbuscular mycorrhizal fungi (AMF), which are beneficial to grapevine growth, is a good indicator of soil health. In contrast, other fungi, such as the pathogen group, can be detrimental to vine growth. The present study aimed to characterize the soil fungal community and the fungal diversity present at six Mediterranean vineyards located in Burgos (Spain), delving into fungal functional guilds and focusing on AMF and pathogenic fungal groups. The fungal structure was investigated using DNA metabarcoding in three soil samples taken from each vineyard, and differences in the abundance of functional guilds were assessed. Similar soil fungal community structures were observed among soil sample repetitions within vineyards. In contrast, adjacent vineyards presented differences in their microbial composition. Saprophytes followed by pathogens were the dominant fungal functional guilds across all vineyards. However, no differences in the relative abundance of the different fungal functional groups were observed among sites. The vineyard with the highest relative abundance of AMF (0.5%) also had the lowest pathogen relative abundance from all the sites (29.76%). Also, sites presenting a high relative abundance of pathogens in soil (>35%) had a low relative abundance of AMF (<0.05%). Our results suggest that the fungal community is affected by the intrinsic properties of the soil and the characteristics of each vineyard’s microsite over the effect of the geographical proximity. In addition, to improve our understanding of the soil microbial ecology, we highlight the necessity of prospecting soil fungal analyses into functional groups, interpreting diversity results within taxonomic groups alongside the total abundance of target groups/species. Full article

This study investigated the isolation and formulation of a bacterial conditioner as a biostimulant for Triticum durum (durum wheat) under salinity stress. An Algerian alkaline–saline soil was sampled, characterized for its physical and chemical characteristics and its culturable and total microbial community (16S rRNA gene metabarcoding). Three bacterial strains showing high 16S rRNA gene similarity to Pseudomonas putida, Bacillus proteolyticus, and Niallia nealsonii were selected for their plant growth-promoting (PGP) traits under different salinity levels, including phosphate solubilisation (194 µg mL⁻¹), hormone production (e.g., gibberellin up to 56 µg mL⁻¹), and good levels of hydrocyanic acid, ammonia, and siderophores. N. nealsonii maintained high indole production under saline conditions, while B. proteolyticus displayed enhanced indole synthesis at higher salt concentrations. Siderophore production remained stable for P. putida and N. nealsonii, whereas for B. proteolyticus a complete inhibition was registered in the presence of salt stress. The consortium density and application were tested under controlled conditions using Medicago sativa as a model plant. The effective biostimulant formulation was tested on Triticum durum under greenhouse experiments. Bacterial inoculation significantly improved plant growth in the presence of salt stress. Root length increased by 91% at 250 mM NaCl. Shoot length was enhanced by 112% at 500 mM NaCl. Total chlorophyll content increased by 208% at 250 mM NaCl. The chlorophyll a/b ratio increased by 117% at 500 mM. Also, reduced amounts of plant extracts were necessary to scavenge 50% of radicals (−22% at 250 mM compared to the 0 mM control). Proline content increased by 20% at both 250 mM and 500 mM NaCl. These results demonstrate the potential of beneficial bacteria as biostimulants to mitigate salt stress and enhance plant yield in saline soils. Full article