Search Results (1,074)

Natural enemies commonly probe larval bodies and frass with their antennae for prey hunting. However, the attractants to natural enemies emitted directly from hosts and host-associated tissues remained largely unknown. Here, we used two generalist noctuid species, Helicoverpa armigera (Hübner) and Spodoptera frugiperda (JE Smith), along with the larval endoparasitoid Microplitis mediator (Haliday) to address the question. Extracts of larval frass of both the noctuid species were strongly attractive to M. mediator females when hosts were fed either maize, cotton, soybean leaves, or an artificial diet without leaf tissues. By using a combination of electrophysiological measurements and behavioral tests, we found that the attractiveness of frass mainly relied on a volatile compound ethyl palmitate. The compound was likely to be a by-product of host digestion involving gut bacteria because an antibiotic supplement in diets reduced the production of the compound in frass and led to the decreased attractiveness of frass to the parasitoids. In contrast, extracts of the larval bodies of both the noctuid species appeared to be less attractive to the parasitoids than their respective fecal extracts, independently of types of food supplied to the larvae. Altogether, larval frass of the two noctuid species was likely to be more important than their bodies in attracting the endoparasitoid species, and the main attractant of frass was probably one of the common metabolites of digestion involving gut microbes, and its emission is likely to be independent of host plant species. Full article

Microbes perform diverse and vital functions in animals, plants, and humans, and among them, plant-associated microbiomes, especially endophytes, have attracted growing scientific interest in recent years. Numerous plant species thriving in diverse environments have been shown to host endophytic microbes. While endophytic bacteria commonly colonize plant tissues such as stems, roots, and leaves, seed-associated endophytes generally exhibit lower diversity compared to those in other plant compartments. Nevertheless, seed-borne microbes are of particular importance, as they represent the initial microbial inoculum that influences a plant’s critical early developmental stages. The seed endophytic microbiome is of particular interest due to its potential for vertical transmission and its capacity to produce a broad array of phytohormones, enzymes, antimicrobial compounds, and other secondary metabolites. Collectively, these functions contribute to enhanced plant biomass and yield, especially under abiotic and biotic stress conditions. Despite their multifaceted roles, seed microbiomes remain underexplored in plant ecology, and their potential benefits are not yet fully understood. This review highlights recent advances in our understanding of the diversity, community composition, mechanisms of action, and agricultural significance of seed endophytic microbes. Furthermore, it synthesizes current insights into how seed endophytes promote plant health and productivity and proposes future research directions to fully harness their potential in sustainable agriculture. Full article

In plateau wetlands, the interactions of herbaceous roots with ectorhizosphere soil microorganisms represent an important way to realize their ecological functions. Global change-induced aridification of plateau wetlands has altered long-established functional synergistic relationships between plant roots and ectorhizosphere soil microbes, but we still know little about this phenomenon. In this context, nine typical wetlands with three different moisture statuses were selected from the eastern Tibetan Plateau in this study to analyze the relationships among herbaceous plant root traits and microbial communities and functions. The results revealed that drought significantly inhibited the accumulation of root biomass and surface area as well as the development of root volumes and diameters. Similarly, drought significantly reduced the diversity of ectorhizosphere soil microbial communities and the relative abundances of key phyla of archaea and bacteria. Redundancy analysis revealed that plant root traits and ectorhizosphere soil microbes were equally regulated by soil physicochemical properties. Functional genes related to carbohydrate metabolism were significantly associated with functional traits related to plant root elongation and nutrient uptake. Functional genes related to carbon and energy metabolism were significantly associated with traits related to plant root support and storage. Key genes such as CS,gltA, and G6PD,zwf help to improve the drought resistance and barrenness resistance of plant roots. This study helps to elucidate the synergistic mechanism of plant and soil microbial functions in plateau wetlands under drought stress, and provides a basis for evolutionary research and conservation of wetland ecosystems in the context of global change. Full article

This study aims to analyze the differences in soil bacterial community structure under different vegetation restoration types, and to explore the role of microorganisms in the process of vegetation restoration on the soil ecosystem of the Grain for Green area in the Loess Plateau. High-throughput sequencing technology was used to analyze the alpha diversity of soil bacteria, community structure characteristics, and the correlation between soil environmental factors and bacterial communities in different artificial Hippophae rhamnoides forests. Soil microbial C and N show a decreasing trend with an increase in the 0–100 cm soil layers. The results indicated that the bacterial communities comprised 24 phyla, 55 classes, 110 orders, 206 families, 348 genera, 680 species, and 1989 OTUs. Additionally, the richness indices and diversity indices of the bacterial community in arbor shrub mixed forest are higher than those in shrub pure forest, and the indices of shrub forest on sunny slope are higher than those on shady slope. Across all samples, the dominant groups were Actinobacteria (37.27% on average), followed by Proteobacteria (23.91%), Acidobacteria (12.75%), and Chloroflexi (12.27%). Soil nutrient supply, such as TOC, TN, AN, AP, and AK, had crucial roles in shaping the composition and diversity of the bacterial communities. The findings reveal that vegetation restoration significantly affected soil bacterial community richness and diversity. Furthermore, based on the results, our data provide a starting point for establishing soil bacterial databases in the Loess Plateau, as well as for the plants associated with the vegetation restoration. Full article

Stipagrostis pennata is an important plant in desert ecosystems. Its seed-endophytic bacteria may play a critical role in plant growth and environmental adaptation processes. This study systematically analyzed the community composition and potential plant growth-promoting (PGP) functions of seed-endophytic bacteria associated with S. pennata. The results showed that while the overall diversity of bacterial communities from different sampling sites was similar, significant differences were observed in specific functional genes and species abundances. Nine endophytic bacterial strains were isolated from the seeds, among which Bacillus altitudinis strain L7 exhibited phosphorus solubilizing capabilities, nitrogen fixing, IAA production, siderophore generation, and multi-hydrolytic enzyme activities. Additionally, the genomic sequencing of L7 revealed the key genes involved in plant growth promotion and environmental adaptation, including Na⁺ efflux systems, K⁺ transport systems, compatible solute synthesis genes, and the gene clusters associated with nitrogen metabolism, IAA synthesis, phosphate solubilization, and siderophore synthesis. Strain L7 exhibits salt and osmotic stress tolerance while promoting plant growth, providing a promising candidate for desert microbial resource utilization and plant biostimulant development. Full article

Ecological restoration in the cold and high-altitude mining areas of the Qinghai–Tibet Plateau is faced with dual challenges of extreme environments and insufficient microbial adaptability. This study aimed to screen local microbial resources with both extreme environmental adaptability and plant-growth-promoting functions. Local fungi (DK; F18-3) and commercially available bacteria (B0) were used as materials to explore their regulatory mechanisms for plant growth, soil physicochemical factors, microbial communities, and metabolic profiles in the field. Compared to bacterial treatments, local fungi treatments exhibited stronger ecological restoration efficacy. In addition, the DK and F18-3 strains, respectively, increased shoot and root biomass by 23.43% and 195.58% and significantly enhanced soil nutrient content and enzyme activity. Microbiome analysis further implied that, compared with the CK, DK treatment could significantly improve the α-diversity of fungi in the rhizosphere soil (the Shannon index increased by 14.27%) and increased the amount of unique bacterial genera in the rhizosphere soil of plants, totaling fourteen genera. Meanwhile, this aggregated the most biomarkers and beneficial microorganisms and strengthened the interactions among beneficial microorganisms. After DK treatment, twenty of the positively accumulated differential metabolites (DMs) in the plant rhizosphere were highly positively associated with six plant traits such as shoot length and root length, as well as beneficial microorganisms (e.g., Apodus and Pseudogymnoascus), but two DMs were highly negatively related to plant pathogenic fungi (including Cistella and Alternaria). Specifically, DK mainly inhibited the growth of pathogenic fungi through regulating the accumulation of D-(+)-Malic acid and Gamma-Aminobutyric acid (Cistella and Alternaria decreased by 84.20% and 58.53%, respectively). In contrast, the F18-3 strain mainly exerted its antibacterial effect by enriching Acidovorax genus microorganisms. This study verified the core role of local fungi in the restoration of mining areas in the Qinghai–Tibet Plateau and provided a new direction for the development of microbial agents for ecological restoration in the Qinghai–Tibet Plateau. Full article

Plant-essential phosphorus (P) is a sparingly available mineral in soils. Phosphorus fertilizers—produced by the transformation of insoluble to soluble phosphates—are thus applied to agroecosystems. With advancements in commercial agriculture, crops have been increasingly adapted to grow in fertile environments. Wild crop relatives, however, are adapted to grow in unfertilized soils. In response to these two conditions of P bioavailability (fertilized agroecosystems and unfertilized natural soils), domesticated crops and wild species employ different strategies to grow and develop. It is essential to understand strategies related to P acquisition that may have been lost to domestication, and here we present, for the first time, that across species, modern cultivars engage in physical (i.e., root morphological) mechanisms while their wild relatives promote ecological (i.e., root-microbial) mechanisms. Domesticated crops showcase shallower root system architecture and engage in topsoil foraging to acquire P from the nutrient-stratified environments common to fertilized agroecosystems. Wild species associate with P-cycling bacteria and AM fungi. This divergence in P recovery strategies is a novel delineation of current research that has implications for enhancing agricultural sustainability. By identifying the traits related to P recovery that have been lost to domestication, we can strengthen the P recovery responses by modern crops and reduce P fertilization. Full article

Surfactants are widely utilized in agriculture as emulsifying, dispersing, anti-foaming, and wetting agents. In these adjuvant roles, the inherent biological activity of the surfactant is secondary to the active ingredients. Here, the hydrophilic non-ionic surface-active tri-block copolymer Pluronic^® F68 is investigated for direct biological activity in wheat. F68 binds to and inserts into lipid membranes, which may benefit crops under abiotic stress. F68’s interactions with Triticum aestivum (var Juniper) seedlings and a seed-borne Bacillus spp. endophyte are presented. At concentrations below 10 g/L, F68-primed wheat seeds exhibited unchanged emergence. Root-applied fluorescein-F68 (fF68) was internalized in root epidermal cells and concentrated in highly mobile endosomes. The potential benefit of F68 in droughted wheat was examined and contrasted with wheat treated with the osmolyte, glycine betaine (GB). Photosystem II activity of droughted plants dropped significantly below non-droughted controls, and no clear benefit of F68 (or GB) during drought or rehydration was observed. However, F68-treated wheat exhibited increased transpiration values (for watered plants only) and enhanced shoot dry mass (for watered and droughted plants), not observed for GB-treated or untreated plants. The release of seed-borne bacterial endophytes into the spermosphere of germinating seeds was not affected by F68 (for F68-primed seeds as well as F68 applied to roots), and the planktonic growth of a purified Bacillus spp. seed endophyte was not reduced by F68 applied below the critical micelle concentration. These studies demonstrated that F68 entered wheat root cells, concentrated in endosomes involved in transport, significantly promoted shoot growth, and showed no adverse effects to plant-associated bacteria. Full article

Several strains of the genus Serratia isolated from the rhizosphere of crops are plant growth-promoting bacteria (PGPB) that may possess various traits associated with nitrogen metabolism, auxin production, and other characteristics. The objective of the present study was to investigate the in vitro and in vivo characteristics of the growth-promoting activity of S. liquefaciens UNJFSC 002 in potato plants. This strain was inoculated into potato varieties (Solanum tuberosum) under laboratory and greenhouse conditions to determine the bacterial strain’s ability to promote growth under controlled conditions. It was found that the S. liquefaciens strain UNJFSC 002 had a significantly greater effect on the fresh and dry weight of the foliage and induced a higher tuber weight per plant and larger tuber diameter compared to the uninoculated potato plants (p < 0.05). Additionally, in vitro, the strain demonstrated the ability to fix atmospheric nitrogen and produce indole-3-acetic acid (IAA), as well as the capacity to solubilise tricalcium phosphate in the laboratory. This research reveals the potential of S. liquefaciens UNJFSC 002 as an inoculant to improve potato production, demonstrating its ability to promote the growth and productivity of potato varieties suitable for direct consumption and processing under controlled conditions. Full article

This study investigates how root color in soybeans affects isoflavone composition, rhizosphere bacterial diversity, total phenolics, total flavonoids, and antioxidant activity under a hydroponic cultivation system. Notably, soybean-brown roots (SBRs) accumulated significantly higher contents of isoflavones, exhibiting approximately a 14.9-fold increase in total glycosides (141.75 to 2121.59 µg/g), 7.3-fold increase in total malonyl-β-glycosides (127.52 to 930.45 µg/g), 2.8-fold increase in total aglycones (1825.90 to 5145.21 µg/g), and 3.9-fold increase in total isoflavones (2095.16 to 8197.26 µg/g) than soybean-white roots (SWRs). Isolated rhizosphere bacteria profiling revealed γ-Proteobacteria as the predominant class in both root types, constituting 77.6% and 73.9% of the bacterial community in SWRs and SBRs, respectively. However, SBRs supported a more diverse bacterial ecosystem, harboring thirteen genera compared to only eight genera in SWRs. Enhanced total phenolics, total flavonoids, and radical scavenging activity were also associated with the SBRs. These findings shed light on the dynamic interplay between root traits, bacterial interactions, and secondary metabolite biosynthesis in hydroponically grown soybeans. This work not only advances our understanding of plant root–microbiome–metabolite relationships but also offers a novel approach to exploring the potential of enhancing secondary metabolites in soybean plants through precision cultivation. Full article

Climate change can have a direct impact on the decomposition of organic matter, as well as indirect effects on peatland vegetation (including carnivorous plants) and the microbial communities associated with this environment. The activity of microbes varies depending on the type of peatland they inhabit. Because some microorganisms are highly sensitive, they can be used as indicators of climate change. However, there is still little knowledge of how changes in the temperature of the environment can affect the microbiome of carnivorous plants. The study was conducted to test the following hypotheses: (1) The effect of rising water temperature on the qualitative and quantitative structure of the microbiome of carnivorous peatland plants depends on the type of peatland; (2) habitats with a higher trophic status stimulate the development of microbial communities in the water, but are an unfavourable habitat for the development of the microbiome of plant traps. Irrespective of the type of peatland, the species richness of microorganisms was much higher in the water than in the traps. As the temperature increased, there was an increase in the abundance of bacteria, heterotrophic flagellates, and testate amoebae, which was much more pronounced in the peat bog than in the carbonate fen. Full article

Heterologous expression of caseins in non-mammalian systems offers a sustainable and scalable alternative for producing milk proteins, with potential applications in the food and biopharmaceutical industries. However, a significant challenge in these systems is achieving proper phosphorylation, a critical post-translational modification required for casein functionality and stability. This review explores the current state of research on heterologous casein production, with a particular focus on the biological and technical hurdles associated with phosphorylation. Specifically, we examine the absence of the mammalian-specific kinase Fam20C in plant and yeast systems and the broader lack of secretory kinase machinery in bacteria, which collectively contribute to impaired phosphorylation fidelity. While some endogenous kinases may partially compensate, they are typically insufficient to replicate the phosphorylation pattern required for functionality. We evaluate potential strategies to address these limitations, analyze the role of phosphorylation in casein functionality, provide insights into existing patents and experimental approaches, and highlight ongoing research efforts. By synthesizing current knowledge and proposing new avenues for innovation, this review aims to provide a roadmap for the successful production of functional heterologous caseins. Full article

The gut microbiota, dominated by bacteria from the Firmicutes, Bacteroidetes, Proteobacteria, and Actinobacteria phyla, plays an essential role in fermenting indigestible carbohydrates, regulating metabolism, synthesizing vitamins, and maintaining immune functions and intestinal barrier integrity. Dysbiosis is associated with obesity development. Shifts in the ratio of Firmicutes to Bacteroidetes, particularly an increase in Firmicutes, may promote enhanced energy storage, appetite dysregulation, and increased inflammatory processes linked to insulin resistance and other metabolic disorders. The purpose of this literature review is to summarize the current state of knowledge on the relationship between the development and treatment of obesity and overweight and the gut microbiota. Current evidence suggests that probiotics, prebiotics, synbiotics, and fecal microbiota transplantation (FMT) can influence gut microbiota composition and metabolic parameters, including body weight and BMI. The most promising effects are observed with probiotic supplementation, particularly when combined with prebiotics, although efficacy depends on strain type, dose, and duration. Despite encouraging preclinical findings, FMT has shown limited and inconsistent results in human studies. Diet and physical activity are key modulators of the gut microbiota. Fiber, plant proteins, and omega-3 fatty acids support beneficial bacteria, while diets low in fiber and high in saturated fats promote dysbiosis. Aerobic exercise increases microbial diversity and supports growth of favorable bacterial strains. While microbiota changes do not always lead to immediate weight loss, modulating gut microbiota represents an important aspect of obesity prevention and treatment strategies. Further research is necessary to better understand the mechanisms and therapeutic potential of these interventions. Full article

Plant microbiota contributes to nutrient absorption, and the production of hormones and vitamins, and plays a crucial role in responding to environmental stress. We hypothesized that Vaccinium spp. harbour a unique microbiota that enables them to coexist in extreme environments such as saline, nutrient-poor, and waterlogged conditions. Upon examining Bacillus spp. endophytes isolated from blueberries, cranberries and lingonberries in vitro, we identified B. halotolerans (Bil-LT1_1, Bil-LT1_2) and B. velezensis (Cran-LT1_8, Ling-NOR4_15) strains that inhibit the growth of five pathogenic fungi and five foodborne bacteria. Whole-genome sequencing provided insights into genome organization and plasticity, helping identify mobile elements and genes potentially acquired through horizontal gene transfer. Functional annotation identified genes associated with plant colonization, stress tolerance, biocontrol activity, and plant growth promotion. Comparative genomic analyses revealed key biosynthetic gene clusters (BGCs) responsible for producing antifungal metabolites, including lipopeptides and polyketides. Genes supporting plant nutrition, growth, and environmental adaptation were present also in these strains. Notably, isolated endophytes exhibited particularly high levels of genomic plasticity, likely due to horizontal gene transfer involving gene ontology (GO) pathways related to survival in polymicrobial and foreign environments. Full article

This study systematically investigated the effects of dietary tea polyphenols (TPs, major bioactive polyphenols from Camellia sinensis with potent antioxidant and anti-inflammatory properties) on the growth performance and intestinal health of hybrid crucian carp HCC2 under chronic crowding stress. A low-density control group (44.4 fish/m³, basal diet without TPs) and four high-density crowding stress groups (222.2 fish/m³) were established, one fed the basal diet without TPs (CS) and three fed basal diets supplemented with 100 (CSLTP), 200 (CSMTP), or 400 (CSHTP) mg/kg TPs. We analyzed the impacts of TPs on growth performance, serum biochemical parameters, antioxidant capacity, expression of lipid metabolism-related genes, and intestinal microbiota composition. The results demonstrated that chronic crowding stress significantly suppressed the final body weight, weight gain rate, and specific growth rate of HCC2, while increasing serum lactate LDH, TG, and ALB and decreasing GLU, LDL-C, ALT, AST, and ALP levels. Dietary TPs supplementation enhanced antioxidant capacity (T-AOC, SOD, CAT, and GSH) and alleviated lipid metabolic disorders by activating the Nrf2/Keap1 and PPARα signaling pathways, thereby upregulating the expression of liver antioxidant genes (CAT and SOD) and fatty acid oxidation genes (CPT1 and acox1). Furthermore, intestinal microbiota analysis revealed that chronic crowding stress significantly increased the abundance of Proteobacteria and decreased the proportion of Firmicutes compared to the low-density control. Dietary TPs intervention, particularly at higher doses, partially restored the Firmicutes abundance and reduced the enrichment of potential pathogenic bacteria associated with stress. This study is the first to comprehensively elucidate the mechanism by which TPs alleviate crowding stress through enhanced antioxidant capacity, metabolic regulation, and microbiota remodeling, providing robust theoretical support for the application of plant-based additives in aquaculture. Full article