Search Results (33)

Bradysia difformis Frey (Diptera: Sciaridae) is a fungus gnat that poses a significant threat to greenhouse cultures, and is attracted to soils devoid of peat. Fungal strains from the German Collection of Microorganisms and Cell Culture (DSMZ), such as Beauveria bassiana, Metarhizium flavoviride, Mucor hiemalis, and Niesslia tinuis, as well as Serendipita indica, were screened for entomopathogenic activity against B. difformis and their capacity to colonize Petunia hybrida cv. “Mitchell” and Ocimum basilicum plants. The survival rates of Bradysia difformis (three instar larvae) treated with Metarhizium flavoviride were 45.33% at 14 days following inoculation with 1 × 10⁶ spores/mL of each fungal strain, when compared to others. We concluded that the fungal strain M. flavoviride could serve as an entomopathogenic fungus with the highest virulence against B. difformis larvae. Although M. flavoviride did not show a beneficial effect as an endophyte, interestingly, the strain Niesslia tinuis exhibited plant growth benefits in Petunia hybrida cv. “Mitchell” by enhancing its shoot length up to 13.18 ± 0.72 cm, whereas the control treatment had a shoot length up to 10.68 ± 0.39. Enzymatic assays confirmed the ability of M. flavoviride to produce cuticle-degrading enzymes such as chitinase and protease. Together, these findings highlight the potential of EMPF—particularly M. flavoviride—as a sustainable biocontrol tool well-suited for peat-free horticultural systems, offering an eco-friendly alternative to chemical insecticides where fungus gnat pressure is typically high. Full article

Modern wheat breeding has largely emphasized aboveground traits, often at the expense of belowground characteristics such as root biomass, architecture, and beneficial microbial associations. This has narrowed genetic diversity, impacting traits essential for stress resilience and efficient nutrient and water acquisition—factors expected to become increasingly critical under climate change. In this study, we evaluated 36 primary synthetic (PS) hexaploid wheat lines developed by crossing Aegilops tauschii with the durum wheat cultivar Langdon (LNG) and compared them with LNG and the hexaploid variety Norin 61 (N61). We observed significant variation in root length, biomass, and associations with fungal endophytes, including beneficial Arbuscular Mycorrhizal Fungi (AMF) and Serendipita indica, and pathogenic Alternaria sp. Clustering analysis based on these traits identified three distinct PS groups: (1) lines with greater root length and biomass, high AMF and S. indica colonization, and low Alternaria infection; (2) lines with intermediate traits; and (3) lines with reduced root traits and high Alternaria susceptibility. Notably, these phenotypic patterns corresponded closely with the soil classification of the Ae. tauschii progenitors’ origin, such as Cambisols (supportive of root growth), and Gleysols and Calcisols (restrictive of root growth). This highlights the soil microenvironment as a key determinant of belowground trait expression. By comparing PS lines with domesticated tetraploid and hexaploid wheat, we identified and selected PS lines derived from diverse Ae. tauschii with enhanced root traits. Our study emphasizes the potential of wild D-genome diversity to restore critical root traits for breeding resilient wheat. Full article

Piriformospora/Serendipita indica has been frequently proved to play a crucial role in enhancing plant adaptation to environmental stresses. However, its influence on blueberry (Vaccinium corymbosum) drought tolerance has not yet been studied. Here, we reported that P. indica colonization can significantly enhance the drought tolerance of blueberry. Physio-biochemical parameter determination results showed that, compared to non-colonized controls (CK), P. indica-colonized (PI) plants exhibited higher leaf chlorophyll and carotenoids contents, photosynthetic capacity, biomass and root antioxidant enzyme activities (superoxide dismutase and catalase), while also exhibiting lower root malondialdehyde content under drought stress (DS). To explore the underlying mechanism, comparative root transcriptome analysis of well-watered (WW) and DS-treated CK and PI blueberry plants was conducted. In total, we identified 14,587 differentially expressed genes (DEGs) across CK-WW vs. CK-DS, PI-WW vs. PI-DS, CK-WW vs. PI-WW and CK-DS vs. PI-DS comparisons. Under DS, stress-, metabolism- and regulation-related DEGs were overwhelmingly upregulated in PI, while being downregulated in CK. Weighted gene co-expression network analysis categorized DEGs into four modules. Of them, the MEblack module was significantly correlated with the PI-DS group, with DEGs enriched in the cell wall macromolecule catabolic process, carbohydrate metabolic process, phenylpropanoid biosynthesis, and so on. Several defense-related genes, including four thaumatin family proteins, were identified as hub genes of this module. DEGs in the MEblue module were expressed at the highest level in CK-DS, followed by in PI-DS. Hub genes of the MEblue module included DEG-encoding lipid transfer protein, abscisic stress ripening protein, and so on. This study demonstrates that P. indica enhances blueberry drought tolerance by enhancing antioxidant ability and mediating the expression of genes related to stress, carbohydrate and secondary metabolism, and cell wall metabolism. Full article

Grapevines (Vitis vinifera L.) face significant challenges from abiotic stresses caused by climate change, including drought, salinity, and temperature extremes. This comprehensive review examined the role of beneficial microorganisms in enhancing grapevine tolerance to these stresses, focusing on arbuscular mycorrhizal fungi (AMF), plant growth-promoting rhizobacteria (PGPR), and endophytes. The study analyzes species-specific effects and their molecular mechanisms, highlighting how single and consortium inoculations improve plant resilience. AMF species, particularly Funneliformis mosseae and Rhizophagus irregularis, demonstrated significant enhancement in drought and salinity tolerance through improved nutrient uptake and stress response modulation. The PGPRs, Bacillus and Pseudomonas species, show remarkable abilities to mitigate various abiotic stresses through mechanisms including phytohormone production and antioxidant defense enhancement. Endophytic microorganisms such as Pseudomonas fluorescens RG11 and Serendipita indica play crucial roles in stress mitigation through melatonin production and improved water retention, respectively. The synergistic effects of combined AMF, PGPR, and PGPF applications led to a significant increase in grapevine drought and salinity tolerance, improving nutrient uptake, photosynthesis rates, and antioxidant defense mechanisms. Molecular analysis revealed that these microbial consortia regulate the expression of stress-responsive genes, particularly VvNCED and VvP5CS, enhancing grapevine resilience through improved osmotic adjustment, ROS scavenging, and hormonal regulation. These findings provide valuable insights into the molecular pathways underlying stress tolerance, offering promising strategies for sustainable viticulture under climate change. Full article

Plant defensin (PDF/DEF), an important pathogenesis-related protein which widely exists in plants, displays broad-spectrum antifungal activities. To date, however, reports on the banana PDFs are very limited. In this study, we identified, cloned, and characterized the five Class I PDFs (MaPDF2.1~MaPDF2.5) in banana (Musa acuminata). Further, their expression in root, corm, leaf, and fruit were studied. MaPDFs exhibited quite different expression patterns in different organs, with MaPDF2.2 as the only member expressing in all the tested organs, and its expression levels in all organs were the highest among all MaPDFs. The MaPDF2.2 expression could be significantly upregulated by both low- and high-temperature stresses but significantly downregulated by the inoculations of plant growth promoting endophytic fungus Serendipita indica and banana Fusarium wilt (FW) pathogen Fusarium oxysporum f. sp. cubense (Foc) Tropical race 4 (FocTR4). Moreover, the S. indica pre-colonization could significantly alleviate the suppression of FocTR4 on MaPDF2.2, suggesting that this MaPDF might contribute greatly to the S. indica-enhanced FW resistance. By using tobacco leaf transient overexpression, the function of MaPDF2.2 was investigated. Its overexpression significantly inhibited the infection of Foc race 1 (Foc1) and FocTR4 in tobacco leaves. Furthermore, in vitro antifungal ability assays revealed that the recombinant His-MaPDF2.2 protein could significantly inhibit the growth of Foc1 and FocTR4, as well as the pigment accumulation of Foc1. Our study revealed the sequence and expression characteristics of banana PDFs and demonstrated the antifungal ability of MaPDF2.2 to FW pathogens. Full article

Drought stress significantly impairs the output of tea plants and the quality of tea products. Although Serendipita indica has demonstrated the ability to enhance drought tolerance in host plants, its impact on tea plants (Camellia sinensis) experiencing drought stress is unknown. This study assessed the response of tea plants by inoculating S. indica under drought conditions. Phenotypic and physiological analyses demonstrated that S. indica mitigated drought damage in tea plants by regulating osmotic equilibrium and antioxidant enzyme activity. Metabolome analysis showed that S. indica promoted the accumulation of flavonoid metabolites, including naringin, (-)-epiafzelechin, naringenin chalcone, and dihydromyricetin, while inhibiting the content of amino acids and derivatives, such as homoarginine, L-arginine, N6-acetyl-L-lysine, and N-palmitoylglycine, during water deficit. The expression patterns of S. indica-stimulated genes were investigated using transcriptome analysis. S. indica-induced drought-responsive genes involved in osmotic regulation, antioxidant protection, transcription factors, and signaling were identified and recognized as possibly significant in S. indica-mediated drought tolerance in tea plants. Particularly, the flavonoid biosynthesis pathway was identified from the metabolomic and transcriptomic analysis using Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Moreover, flavonoid biosynthesis-related genes were identified. S. indica-inoculation significantly upregulated the expression of cinnamate 4-hydroxylase (C4H), chalcone synthase (CHS), flavanone 3-hydroxylase (F3H), dihydroflavonol 4-reductase (DFR), anthocyanidin reductase (ANR), and leucoanthocyanidin reductase (LAR) genes compared to uninoculated plants subjected to water stress. Consequently, we concluded that S. indica inoculation primarily alleviates drought stress in tea plants by modulating the flavonoid biosynthesis pathway. These results will provide insights into the mechanisms of S. indica-enhanced drought tolerance in tea plants and establish a solid foundation for its application as a microbial agent in the management of drought in tea plants cultivation. Full article

This study investigates the effect of Serendipita indica inoculation on the growth, structural characteristics of leaf epidermis, photosynthetic parameters, and antioxidant and osmoregulation capacities of Agrostis stolonifera L. under different drought stresses (normal moisture management: at 70–75% of the field capacity, low drought: at 55–60% field capacity, moderate drought: at 40–45% of the field capacity, and severe drought: at 25–30% of the field capacity). The results showed that inoculation with S. indica significantly enhanced the growth potential of A. stolonifera compared to uninoculated controls, and then under drought stress conditions, inoculation with S. indica significantly alleviated the inhibition of the growth and development of A. stolonifera, especially under mild and moderate drought stresses. These improvements were evident in both aboveground and underground parts, leaf relative water content, total root length, and root surface area after 25 days of drought treatments. Inoculated plants also exhibited higher levels of photosynthetic pigments, net photosynthetic rate (Pn), stomatal conductance (Gs), and transpiration rate (Tr) under drought conditions. Additionally, S. indica inoculation significantly increased the activities of catalase (CAT), peroxidase (POD), and ascorbate peroxidase (APX), as well as the soluble sugar, soluble protein, and proline levels under drought-stressed and non-stressed conditions. In addition, the increases in the malondialdehyde (MDA) content and relative conductivity (RC) of leaves were significantly lower in the inoculated group compared to the control group. In conclusion, the symbiosis with S. indica promotes the growth of A. stolonifera under drought stress, likely by enhancing photosynthesis, osmoregulatory substances, and antioxidant enzyme activities. Full article

Serendipita indica is a very promising root-associated endophytic fungus that is widely used on various plants; however, whether it affects the growth and physiological activity of an oilseed crop (Camellia oleifera) under field conditions remains unclear. In this study, we analyzed the effects of S. indica inoculation on root colonization rate, growth rate, photosynthetic parameters, mineral element concentrations and related gene expression, and sugar concentrations and expression of their transporter genes in four-year-old C. oleifera trees in the field. The results showed that the root colonization rate of C. oleifera increased from 3.37% to 9.42% following being inoculated with S. indica. Inoculation with S. indica significantly increased the plant height (46.81%), net photosynthetic rate (69.16%), nitrogen balance index (14.44%), chlorophyll index (21.08%), leaf K (7.4%), leaf Ca (13.52%), root P (17.75%), root K (12.80%), soil NH₄⁺-N (17.78%), available K (26.66%), Olsen-P (184.30%), easily extractable glomalin-related soil protein (39.26%), and soil organic carbon (16.25%) concentrations compared to the uninoculated treatment. Inoculation with S. indica also significantly up-regulated the expression of CoHKT1;1 and CoCAX1;2 in the leaves and roots and CoPht1;1, CoPht1;2, and CoPht1;3 in the leaves. Plants inoculated with S. indica also presented significantly higher leaf glucose, fructose, and sucrose concentrations, accompanied by up-regulated expression of CoSWEET2a, CoSWEET7, CoSWEET9b, CoSWEET17a, and CoSWEET17b. These results suggest that S. indica has significant potential as a biostimulant for enhancing the growth and nutritional profile of C. oleifera, thereby contributing to sustainable oilseed production. Full article

In recent years, recurrent droughts have significantly affected spring barley production, reducing the quantity and quality of grain. This study aims to identify genotype-specific traits and the drought resilience of six different Hordeum vulgare L. (spring barley) genotypes, while also examining the potential of potassium application and fungal endophyte Serendipita indica inoculation to mitigate the negative effects of dry periods during the growing season. Field experiments were conducted over a three-year period from 2020 to 2022, measuring physiological, growth, and yield parameters. To get insight into the physiological state of the plants, we measured the soluble sugars content and the ratio of stable carbon isotopes in the flag leaf tissue, which reflects conditions during its formation. The dominant factors that influenced the measured parameters were the genotypes and seasons, as well as their interaction, rather than other experimental factors. The results showed that the Spitfire and Accordine varieties were the best performing in both the 2020 and 2021 seasons, as indicated by their yield. However, in the drier 2022 season, the yield of these two varieties decreased significantly (to 55% for Spitfire and to 69% for Accordine of their yield in 2021), while for the arid-region genotypes, it remained at the same level as the previous year. This study sheds light on the potential of various genotypes to withstand periods of drought and the effectiveness of using potassium application and S. indica inoculation as mitigation approaches. Full article

Fungal-bacterial combinations have a significant role in increasing and improving plant health under various stress conditions. Metabolites secreted by fungi and bacteria play an important role in this process. Our study emphasizes the significance of secondary metabolites secreted by the fungus Serendipita indica alone and by an actinobacterium Zhihengliuella sp. ISTPL4 under normal growth conditions and arsenic (As) stress condition. Here, we evaluated the arsenic tolerance ability of S. indica alone and in combination with Z. sp. ISTPL4 under in vitro conditions. The growth of S. indica and Z. sp. ISTPL4 was measured in varying concentrations of arsenic and the effect of arsenic on spore size and morphology of S. indica was determined using confocal microscopy and scanning electron microscopy. The metabolomics study indicated that S. indica alone in normal growth conditions and under As stress released pentadecanoic acid, glycerol tricaprylate, L-proline and cyclo(L-prolyl-L-valine). Similarly, d-Ribose, 2-deoxy-bis(thioheptyl)-dithioacetal were secreted by a combination of S. indica and Z. sp. ISTPL4. Confocal studies revealed that spore size of S. indica decreased by 18% at 1.9 mM and by 15% when in combination with Z. sp. ISTPL4 at a 2.4 mM concentration of As. Arsenic above this concentration resulted in spore degeneration and hyphae fragmentation. Scanning electron microscopy (SEM) results indicated an increased spore size of S. indica in the presence of Z. sp. ISTPL4 (18 ± 0.75 µm) compared to S. indica alone (14 ± 0.24 µm) under normal growth conditions. Our study concluded that the suggested combination of microbial consortium can be used to increase sustainable agriculture by combating biotic as well as abiotic stress. This is because the metabolites released by the microbial combination display antifungal and antibacterial properties. The metabolites, besides evading stress, also confer other survival strategies. Therefore, the choice of consortia and combination partners is important and can help in developing strategies for coping with As stress. Full article

Citrus plants are prone to phosphorus (P) deficiency, especially in acidic soil, making them more dependent on root-associated endophytic fungi for growth and development. Beni-Madonna, a hybrid of Citrus nanko × C. amakusa, is a citrus known as “tangor” that is highly popular in China and other parts of the world due to its deep red color and jelly-like flesh. In this study, the inoculation response to two arbuscular mycorrhizal fungi (Diversispora versiformis, Dv; Funneliformis mosseae, Fm) and an endophytic fungus (Serendipita indica, Si) with regard to the growth, leaf gas exchange, light energy efficiency, P levels, acid phosphatase activity, and expression of the purple acid phosphatase (PAP) and phosphate transporter (PT) genes through a potted experiment using Beni-Madonna (tangor) citrus plants grafted on trifoliate orange (Poncirus trifoliata) was studied. Two years following inoculation, the root fungal colonization rates of inoculated plants were significantly increased, accompanied by an increase in plant height and stem diameter, with Si presenting the best effect. Fungal inoculations also significantly increased the leaf chlorophyll index, nitrogen-balance index, photosynthesis rate, stomatal conductance, transpiration rate, photosynthetic efficiency, and quantum yield of PSII, while it reduced photoinhibition and heat dissipation, with Si having the best effect on light energy efficiency. Si significantly increased leaf and root P levels, as well as root CsPAP1‒3, CsPT2, CsPT3, and CsPT7 expression and soil acid phosphatase activity; Fm in mycorrhizal fungi significantly increased leaf and root P levels, as well as root CsPT1 and CsPT7 expression and root/soil acid phosphatase activity. These observations suggested an advantage of Si over the other two AMF in terms of improved plant growth and P acquisition, while Fm displayed prominent effects on increased photosynthetic efficiency. Full article

Polygonum cuspidatum is a traditional medicinal plant enriched with resveratrol and polydatin. However, low temperatures reduce the medicinal component contents of P. cuspidatum, and prolonged low temperatures also affect the growth and survival of P. cuspidatum at the seedling stage. It is unclear whether a culturable endophytic fungus Serendipita indica is able to enhance P. cuspidatum’s low-temperature tolerance and medicinal components. The objective of this study was to examine the biomass, leaf gas exchange, antioxidant enzyme activity, proline levels, medicinal constituent levels, and the expression of the resveratrol synthase (PcRS) and resveratrol-forming stilbene synthase 11 (PcRS11) genes of potted P. cuspidatum plants inoculated with S. indica at low temperatures (10 °C/6 °C, 12 h/12 h, day/night temperature). The six-week low-temperature treatment significantly reduced the root fungal colonization, biomass production, and leaf gas exchange variables, whereas S. indica inoculation significantly increased shoot and root biomass, photosynthetic rate, stomatal conductance, and transpiration rate at low temperatures. S. indica inoculation significantly increased superoxide dismutase and catalase activity as well as proline levels in leaves at low temperatures. The magnitude of root chrysophanol, emodin, polydatin, and resveratrol levels decreased by low temperatures was greater in uninoculated plants than in inoculated plants. Inoculation of S. indica, on the other hand, significantly increased the four medicinal component levels in roots at low temperatures, with a greater magnitude rise in chrysophanol, polydatin, and resveratrol at low temperatures than at suitable temperatures. The low-temperature treatment down-regulated the expression of PcRS and PcRS11 genes in roots, while S. indica up-regulated the expression of PcRS and PcRS11 genes at low temperatures. This implies that S. indica acts as a powerful microbial stimulant on P. cuspidatum to promote low-temperature resistance and medicinal component levels. Full article

The main objective of this study was to investigate the influence of Serendipita indica on the growth of Tartary buckwheat plants. This study highlighted that the roots of Tartary buckwheat can be colonized by S. indica and that this fungal endophyte improved plants height, fresh weight, dry weight, and grain yield. In the meantime, the colonization of S. indica in Tartary buckwheat leaves resulted in elevated levels of photosynthesis, plant hormone content, antioxidant enzyme activity, proline content, chlorophyll content, soluble sugars, and protein content. Additionally, the introduction of S. indica to Tartary buckwheat roots led to a substantial rise in the levels of flavonoids and phenols found in the leaves and seeds of Tartary buckwheat. In addition, S. indica colonization reduced the content of malondialdehyde and hydrogen peroxide when compared to non-colonized plants. Importantly, the drought tolerance of Tartary buckwheat plants is increased, which benefits from physiology and bio-chemical changes in plants after S. indica colonized. In conclusion, we have shown that S. indica can improve systematic resistance and promote the growth of Tartary buckwheat by enhancing the photosynthetic capacity of Tartary buckwheat, inducing the production of IAA, increasing the content of secondary metabolites such as total phenols and total flavonoids, and improving the antioxidant enzyme activity of the plant. Full article

Serendipita indica, a mutualistic root endophytic fungus, has gained attention for its potential to enhance plant health and resistance to various stresses. This study investigated the impact of S. indica (strain DSM 11827) on plant growth promotion and the management of black rot disease. This is a devastating bacterial ailment caused by Xanthomonas campestris pv. campestris, which affects cruciferous crops worldwide. The experiment was conducted under sterile conditions in a phytotron for 10 weeks. It involved the substrate and seed inoculation of S. indica in a cabbage crop. The findings suggested that S. indica establishes mutualistic relationships with cruciferous plants, positively influencing their growth while simultaneously reducing their susceptibility to black rot disease. Plant morphological and physiological parameters were enhanced by S. indica application. Additionally, bio stress markers were also enhanced in response to black rot disease. Moreover, disease severity was reduced by 27.9% and 18.8% in the substrate and seeds treated with S. indica, respectively. However, our findings did not report any antagonistic effect between S. indica and two pathogens, i.e., Xanthomonas campestris pv. campestris and Alternaria brassicicola under the in vitro test, suggesting that the suppression of black rot disease in cabbage seedlings was induced indirectly by S. indica. This study, therefore, underscores the promising prospect of utilizing S. indica to promote crop productivity and combat the destructive impact of black rot disease in cruciferous plants, contributing to more sustainable and resilient agriculture. Full article

The overuse of chemical pesticides and fertilizers in crop farming has led to a decrease in crop quality and negative impacts on soil and the environment. It is crucial to adopt alternative strategies to maintain soil and environmental quality while enhancing crop growth and yield. To explore this, a study was conducted under greenhouse conditions to investigate the effect of Rhizobium tropici CIAT 899 alone, as well as in association with mycorrhizae (Rhizophagus irregularis) and endophytic fungus (Serendipita indica), on the growth, yield, and nutrient status of snap bean plants. At harvest, the rhizobial strain CIAT 899 demonstrated the highest effectiveness. It significantly increased the number of nodules in both Contender and Garrafal Enana varieties by 6.97% and 14.81%, respectively, compared with the control without inoculation. Furthermore, the results indicated that co-inoculation of Rhizobium and symbiotic fungi had positive effects on nitrogen content, phosphorus availability, and overall plant growth. Regardless of the variety, plants inoculated with R. tropici CIAT 899 and Serendipita indica exhibited the highest values for plant growth parameters. This combination resulted in 168% and 135% increases in root dry biomass, as well as 140% and 225% increases in the number of pods for Contender and Garrafal Enana, respectively, compared with the control at harvest. Additionally, this study highlights the potential benefits of combining R. tropici with either Serendipita indica or Rhizophagus irregularis in terms of nitrogen and phosphorus uptake. These symbiotic microorganisms demonstrated synergistic interactions with snap bean plants, leading to improved mineral nutrition and enhanced growth. Overall, these findings suggest that utilizing these symbiotic microorganisms can effectively enhance the mineral nutrition and growth of snap bean plants. Full article