International Journal of Molecular Sciences

19 pages, 3618 KiB

Open AccessArticle

Comparative Analysis of Transcriptomics and Metabolomics Reveals Defense Mechanisms in Melon Cultivars against Pseudoperonospora cubensis Infection

by Yueming Ling, Xianpeng Xiong, Wenli Yang, Bin Liu, Yue Shen, Lirong Xu, Fuyuan Lu, Meihua Li, Yangdong Guo and Xuejun Zhang

Int. J. Mol. Sci. 2023, 24(24), 17552; https://doi.org/10.3390/ijms242417552 - 16 Dec 2023

Cited by 5 | Viewed by 2166

Abstract

Melon (Cucumis melo L.) represents an agriculturally significant horticultural crop that is widely grown for its flavorful fruits. Downy mildew (DM), a pervasive foliar disease, poses a significant threat to global melon production. Although several quantitative trait loci related to DM resistance [...] Read more.

Melon (Cucumis melo L.) represents an agriculturally significant horticultural crop that is widely grown for its flavorful fruits. Downy mildew (DM), a pervasive foliar disease, poses a significant threat to global melon production. Although several quantitative trait loci related to DM resistance have been identified, the comprehensive genetic underpinnings of this resistance remain largely uncharted. In this study, we utilized integrative transcriptomics and metabolomics approaches to identify potential resistance-associated genes and delineate the strategies involved in the defense against DM in two melon cultivars: the resistant ‘PI442177′ (‘K10-1′) and the susceptible ‘Huangdanzi’ (‘K10-9′), post-P. cubensis infection. Even in the absence of the pathogen, there were distinctive differentially expressed genes (DEGs) between ‘K10-1′ and ‘K10-9′. When P. cubensis was infected, certain genes, including flavin-containing monooxygenase (FMO), receptor-like protein kinase FERONIA (FER), and the HD-ZIP transcription factor member, AtHB7, displayed pronounced expression differences between the cultivars. Notably, our data suggest that following P. cubensis infection, both cultivars suppressed flavonoid biosynthesis via the down-regulation of associated genes whilst concurrently promoting lignin production. The complex interplay of transcriptomic and metabolic responses elucidated by this study provides foundational insights into melon’s defense mechanisms against DM. The robust resilience of ‘K10-1′ to DM is attributed to the synergistic interaction of its inherent transcriptomic and metabolic reactions. Full article

(This article belongs to the Special Issue Advances in Plant–Pathogen Interactions: 3rd Edition)

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14 pages, 4597 KiB

Open AccessArticle

Genome-Wide Identification and Characterization of Effector Candidates with Conserved Motif in Falciphora oryzae

by Mengdi Dai, Zhenzhu Su, Xueming Zhu, Lin Li, Ziran Ye, Xiangfeng Tan, Dedong Kong, Xiaohong Liu and Fucheng Lin

Int. J. Mol. Sci. 2024, 25(1), 650; https://doi.org/10.3390/ijms25010650 - 4 Jan 2024

Cited by 1 | Viewed by 2090

Abstract

Microbes employ effectors to disrupt immune responses and promote host colonization. Conserved motifs including RXLR, LFLAK-HVLVxxP (CRN), Y/F/WxC, CFEM, LysM, Chitin-bind, DPBB_1 (PNPi), and Cutinase have been discovered to play crucial roles in the functioning of effectors in filamentous fungi. Nevertheless, little is [...] Read more.

Microbes employ effectors to disrupt immune responses and promote host colonization. Conserved motifs including RXLR, LFLAK-HVLVxxP (CRN), Y/F/WxC, CFEM, LysM, Chitin-bind, DPBB_1 (PNPi), and Cutinase have been discovered to play crucial roles in the functioning of effectors in filamentous fungi. Nevertheless, little is known about effectors with conserved motifs in endophytes. This research aims to discover the effector genes with conserved motifs in the genome of rice endophyte Falciphora oryzae. SignalP identified a total of 622 secreted proteins, out of which 227 were predicted as effector candidates by EffectorP. By utilizing HMM features, we discovered a total of 169 effector candidates with conserved motifs and three novel motifs. Effector candidates containing LysM, CFEM, DPBB_1, Cutinase, and Chitin_bind domains were conserved across species. In the transient expression assay, it was observed that one CFEM and one LysM activated cell death in tobacco leaves. Moreover, two CFEM and one Chitin_bind inhibited cell death induced by Bax protein. At various points during the infection, the genes’ expression levels were increased. These results will help to identify functional effector proteins involving omics methods using new bioinformatics tools, thus providing a basis for the study of symbiosis mechanisms. Full article

(This article belongs to the Special Issue Advances in Plant–Pathogen Interactions: 3rd Edition)

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17 pages, 6299 KiB

Open AccessArticle

The Auto-Regulation of ATL2 E3 Ubiquitin Ligase Plays an Important Role in the Immune Response against Alternaria brassicicola in Arabidopsis thaliana

by Daewon Kim, Su Jeong Jeon, Jeum Kyu Hong, Min Gab Kim, Sang Hee Kim, Ulhas S. Kadam, Woe-Yeon Kim, Woo Sik Chung, Gary Stacey and Jong Chan Hong

Int. J. Mol. Sci. 2024, 25(4), 2388; https://doi.org/10.3390/ijms25042388 - 17 Feb 2024

Cited by 4 | Viewed by 2313 | Correction

Abstract

The ubiquitin/26S proteasome system is a crucial regulatory mechanism that governs various cellular processes in plants, including signal transduction, transcriptional regulation, and responses to biotic and abiotic stressors. Our study shows that the RING-H2-type E3 ubiquitin ligase, Arabidopsis Tóxicos en Levadura 2 ( [...] Read more.

The ubiquitin/26S proteasome system is a crucial regulatory mechanism that governs various cellular processes in plants, including signal transduction, transcriptional regulation, and responses to biotic and abiotic stressors. Our study shows that the RING-H2-type E3 ubiquitin ligase, Arabidopsis Tóxicos en Levadura 2 (ATL2), is involved in response to fungal pathogen infection. Under normal growth conditions, the expression of the ATL2 gene is low, but it is rapidly and significantly induced by exogenous chitin. Additionally, ATL2 protein stability is markedly increased via chitin treatment, and its degradation is prolonged when 26S proteasomal function is inhibited. We found that an atl2 null mutant exhibited higher susceptibility to Alternaria brassicicola, while plants overexpressing ATL2 displayed increased resistance. We also observed that the hyphae of A. brassicicola were strongly stained with trypan blue staining, and the expression of A. brassicicola Cutinase A (AbCutA) was dramatically increased in atl2. In contrast, the hyphae were weakly stained, and AbCutA expression was significantly reduced in ATL2-overexpressing plants. Using bioinformatics, live-cell confocal imaging, and cell fractionation analysis, we revealed that ATL2 is localized to the plasma membrane. Further, it is demonstrated that the ATL2 protein possesses E3 ubiquitin ligase activity and found that cysteine 138 residue is critical for its function. Moreover, ATL2 is necessary to successfully defend against the A. brassicicola fungal pathogen. Altogether, our data suggest that ATL2 is a plasma membrane-integrated protein with RING-H2-type E3 ubiquitin ligase activity and is essential for the defense response against fungal pathogens in Arabidopsis. Full article

(This article belongs to the Special Issue Advances in Plant–Pathogen Interactions: 3rd Edition)

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15 pages, 4663 KiB

Open AccessArticle

A Glycosyl Hydrolase 5 Family Protein Is Essential for Virulence of Necrotrophic Fungi and Can Suppress Plant Immunity

by Xiaofan Liu, Huihui Zhao, Jiatao Xie, Yanping Fu, Bo Li, Xiao Yu, Tao Chen, Yang Lin, Daohong Jiang and Jiasen Cheng

Int. J. Mol. Sci. 2024, 25(5), 2693; https://doi.org/10.3390/ijms25052693 - 26 Feb 2024

Cited by 3 | Viewed by 1625

Abstract

Phytopathogenic fungi normally secrete large amounts of CWDEs to enhance infection of plants. In this study, we identified and characterized a secreted glycosyl hydrolase 5 family member in Sclerotinia sclerotiorum (SsGH5, Sclerotinia sclerotiorum Glycosyl Hydrolase 5). SsGH5 was significantly upregulated during the early [...] Read more.

Phytopathogenic fungi normally secrete large amounts of CWDEs to enhance infection of plants. In this study, we identified and characterized a secreted glycosyl hydrolase 5 family member in Sclerotinia sclerotiorum (SsGH5, Sclerotinia sclerotiorum Glycosyl Hydrolase 5). SsGH5 was significantly upregulated during the early stages of infection. Knocking out SsGH5 did not affect the growth and acid production of S. sclerotiorum but resulted in decreased glucan utilization and significantly reduced virulence. In addition, Arabidopsis thaliana expressing SsGH5 became more susceptible to necrotrophic pathogens and basal immune responses were inhibited in these plants. Remarkably, the lost virulence of the ΔSsGH5 mutants was restored after inoculating onto SsGH5 transgenic Arabidopsis. In summary, these results highlight that S. sclerotiorum suppresses the immune responses of Arabidopsis through secreting SsGH5, and thus exerts full virulence for successful infection. Full article

(This article belongs to the Special Issue Advances in Plant–Pathogen Interactions: 3rd Edition)

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16 pages, 1188 KiB

Open AccessArticle

Molecular Mechanisms of the Stripe Rust Interaction with Resistant and Susceptible Wheat Genotypes

by Taras Nazarov, Yan Liu, Xianming Chen and Deven R. See

Int. J. Mol. Sci. 2024, 25(5), 2930; https://doi.org/10.3390/ijms25052930 - 2 Mar 2024

Cited by 6 | Viewed by 2155

Abstract

Rust fungi cause significant damage to wheat production worldwide. In order to mitigate disease impact and improve food security via durable resistance, it is important to understand the molecular basis of host–pathogen interactions. Despite a long history of research and high agricultural importance, [...] Read more.

Rust fungi cause significant damage to wheat production worldwide. In order to mitigate disease impact and improve food security via durable resistance, it is important to understand the molecular basis of host–pathogen interactions. Despite a long history of research and high agricultural importance, still little is known about the interactions between the stripe rust fungus and wheat host on the gene expression level. Here, we present analysis of the molecular interactions between a major wheat pathogen—Puccinia striiformis f. sp. tritici (Pst)—in resistant and susceptible host backgrounds. Using plants with durable nonrace-specific resistance along with fully susceptible ones allowed us to show how gene expression patterns shift in compatible versus incompatible interactions. The pathogen showed significantly greater number and fold changes of overexpressed genes on the resistant host than the susceptible host. Stress-related pathways including MAPK, oxidation–reduction, osmotic stress, and stress granule formation were, almost exclusively, upregulated in the resistant host background, suggesting the requirement of the resistance-countermeasure mechanism facilitated by Pst. In contrast, the susceptible host background allowed for broad overrepresentation of the nutrient uptake pathways. This is the first study focused on the stripe rust pathogen–wheat interactions, on the whole transcriptome level, from the pathogen side. It lays a foundation for the better understanding of the resistant/susceptible hosts versus pathogenic fungus interaction in a broader sense. Full article

(This article belongs to the Special Issue Advances in Plant–Pathogen Interactions: 3rd Edition)

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24 pages, 1752 KiB

Open AccessReview

Looking for Resistance to Soft Rot Disease of Potatoes Facing Environmental Hypoxia

by Tomasz Maciag, Edmund Kozieł, Katarzyna Otulak-Kozieł, Sylwia Jafra and Robert Czajkowski

Int. J. Mol. Sci. 2024, 25(7), 3757; https://doi.org/10.3390/ijms25073757 - 28 Mar 2024

Cited by 3 | Viewed by 2125

Abstract

Plants are exposed to various stressors, including pathogens, requiring specific environmental conditions to provoke/induce plant disease. This phenomenon is called the “disease triangle” and is directly connected with a particular plant–pathogen interaction. Only a virulent pathogen interacting with a susceptible plant cultivar will [...] Read more.

Plants are exposed to various stressors, including pathogens, requiring specific environmental conditions to provoke/induce plant disease. This phenomenon is called the “disease triangle” and is directly connected with a particular plant–pathogen interaction. Only a virulent pathogen interacting with a susceptible plant cultivar will lead to disease under specific environmental conditions. This may seem difficult to accomplish, but soft rot Pectobacteriaceae (SRPs) is a group virulent of pathogenic bacteria with a broad host range. Additionally, waterlogging (and, resulting from it, hypoxia), which is becoming a frequent problem in farming, is a favoring condition for this group of pathogens. Waterlogging by itself is an important source of abiotic stress for plants due to lowered gas exchange. Therefore, plants have evolved an ethylene-based system for hypoxia sensing. Plant response is coordinated by hormonal changes which induce metabolic and physiological adjustment to the environmental conditions. Wetland species such as rice (Oryza sativa L.), and bittersweet nightshade (Solanum dulcamara L.) have developed adaptations enabling them to withstand prolonged periods of decreased oxygen availability. On the other hand, potato (Solanum tuberosum L.), although able to sense and response to hypoxia, is sensitive to this environmental stress. This situation is exploited by SRPs which in response to hypoxia induce the production of virulence factors with the use of cyclic diguanylate (c-di-GMP). Potato tubers in turn reduce their defenses to preserve energy to prevent the negative effects of reactive oxygen species and acidification, making them prone to soft rot disease. To reduce the losses caused by the soft rot disease we need sensitive and reliable methods for the detection of the pathogens, to isolate infected plant material. However, due to the high prevalence of SRPs in the environment, we also need to create new potato varieties more resistant to the disease. To reach that goal, we can look to wild potatoes and other Solanum species for mechanisms of resistance to waterlogging. Potato resistance can also be aided by beneficial microorganisms which can induce the plant’s natural defenses to bacterial infections but also waterlogging. However, most of the known plant-beneficial microorganisms suffer from hypoxia and can be outcompeted by plant pathogens. Therefore, it is important to look for microorganisms that can withstand hypoxia or alleviate its effects on the plant, e.g., by improving soil structure. Therefore, this review aims to present crucial elements of potato response to hypoxia and SRP infection and future outlooks for the prevention of soft rot disease considering the influence of environmental conditions. Full article

(This article belongs to the Special Issue Advances in Plant–Pathogen Interactions: 3rd Edition)

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17 pages, 5205 KiB

Open AccessArticle

Genome-Wide Identification and Multi-Stress Response Analysis of the DABB-Type Protein-Encoding Genes in Brassica napus

by Siyi Wang, Kunmei Wang, Qi Xia and Shitou Xia

Int. J. Mol. Sci. 2024, 25(11), 5721; https://doi.org/10.3390/ijms25115721 - 24 May 2024

Cited by 1 | Viewed by 1128

Abstract

The DABB proteins, which are characterized by stress-responsive dimeric A/B barrel domains, have multiple functions in plant biology. In Arabidopsis thaliana, these proteins play a crucial role in defending against various pathogenic fungi. However, the specific roles of DABB proteins in Brassica [...] Read more.

The DABB proteins, which are characterized by stress-responsive dimeric A/B barrel domains, have multiple functions in plant biology. In Arabidopsis thaliana, these proteins play a crucial role in defending against various pathogenic fungi. However, the specific roles of DABB proteins in Brassica napus remain elusive. In this study, 16 DABB encoding genes were identified, distributed across 10 chromosomes of the B. napus genome, which were classified into 5 branches based on phylogenetic analysis. Genes within the same branch exhibited similar structural domains, conserved motifs, and three-dimensional structures, indicative of the conservation of BnaDABB genes (BnaDABBs). Furthermore, the enrichment of numerous cis-acting elements in hormone induction and light response were revealed in the promoters of BnaDABBs. Expression pattern analysis demonstrated the involvement of BnaDABBs, not only in the organ development of B. napus but also in response to abiotic stresses and Sclerotinia sclerotiorum infection. Altogether, these findings imply the significant impacts of BnaDABBs on plant growth and development, as well as stress responses. Full article

(This article belongs to the Special Issue Advances in Plant–Pathogen Interactions: 3rd Edition)

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21 pages, 2427 KiB

Open AccessArticle

Diversity and Pathogenicity of Fusarium Root Rot Fungi from Canola (Brassica napus) in Alberta, Canada

by Haitian Yu, Kan-Fa Chang, Rudolph Fredua-Agyeman, Sheau-Fang Hwang and Stephen E. Strelkov

Int. J. Mol. Sci. 2024, 25(11), 6244; https://doi.org/10.3390/ijms25116244 - 5 Jun 2024

Cited by 1 | Viewed by 1543

Abstract

Root rot disease poses a significant threat to canola (Brassica napus), underscoring the need for a comprehensive understanding of its causal agents for more effective disease mitigation. The composition and diversity of fungal pathogens associated with root rot of canola in [...] Read more.

Root rot disease poses a significant threat to canola (Brassica napus), underscoring the need for a comprehensive understanding of its causal agents for more effective disease mitigation. The composition and diversity of fungal pathogens associated with root rot of canola in Alberta, Canada, were evaluated from plant tissue samples collected in 2021 and 2022. The study revealed Fusarium spp. as the predominant pathogens found in almost all surveyed fields. Fusarium avenaceum, F. redolens, and F. solani were among the most frequently recovered species. Greenhouse trials confirmed their pathogenicity, with F. avenaceum and F. sporotrichioides found to be particularly aggressive. Additionally, F. sporotrichioides and F. commune were identified for the first time as canola root rot pathogens. Inoculation with isolates of most species resulted in significant reductions in seedling emergence, plant height, and shoot and root dry weights. Analysis of translation elongation factor 1-α (TEF-1α) and internal transcribed spacer (ITS) sequences confirmed the identity of the Fusarium spp., while concatenating the ITS and TEF-1α sequences enabled improved species differentiation. Geographic and year effects did not influence fungal diversity or aggressiveness, as determined by principal component analysis. This study emphasized the high diversity and impact of Fusarium spp. in causing canola root rot. Full article

(This article belongs to the Special Issue Advances in Plant–Pathogen Interactions: 3rd Edition)

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13 pages, 1569 KiB

Open AccessReview

Polyamines in Plant–Pathogen Interactions: Roles in Defense Mechanisms and Pathogenicity with Applications in Fungicide Development

by Qi Yi, Min-Jeong Park, Kieu Thi Xuan Vo and Jong-Seong Jeon

Int. J. Mol. Sci. 2024, 25(20), 10927; https://doi.org/10.3390/ijms252010927 - 11 Oct 2024

Cited by 3 | Viewed by 1405

Abstract

Polyamines (PAs), which are aliphatic polycationic compounds with a low molecular weight, are found in all living organisms and play essential roles in plant–pathogen interactions. Putrescine, spermidine, and spermine, the most common PAs in nature, respond to and function differently in plants and [...] Read more.

Polyamines (PAs), which are aliphatic polycationic compounds with a low molecular weight, are found in all living organisms and play essential roles in plant–pathogen interactions. Putrescine, spermidine, and spermine, the most common PAs in nature, respond to and function differently in plants and pathogens during their interactions. While plants use certain PAs to enhance their immunity, pathogens exploit PAs to facilitate successful invasion. In this review, we compile recent studies on the roles of PAs in plant–pathogen interactions, providing a comprehensive overview of their roles in both plant defense and pathogen pathogenicity. A thorough understanding of the functions of PAs and conjugated PAs highlights their potential applications in fungicide development. The creation of new fungicides and compounds derived from PAs demonstrates their promising potential for further research and innovation in this field. Full article

(This article belongs to the Special Issue Advances in Plant–Pathogen Interactions: 3rd Edition)

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12 pages, 2452 KiB

Open AccessArticle

Molecular Insights into the Reproductive Patterns and Genetic Structure of Wheat Stripe Rust in Ili, Xinjiang

by Hanlin Lai, Yue Li, Feifei Deng, Hong Yang, Jin Li, Jianghua Chen, Jingjing Sun, Guangkuo Li, W. G. Dilantha Fernando and Haifeng Gao

Int. J. Mol. Sci. 2024, 25(22), 12357; https://doi.org/10.3390/ijms252212357 - 18 Nov 2024

Cited by 1 | Viewed by 892

Abstract

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is a globally significant fungal disease that seriously threatens wheat yield, particularly in China. This study investigates the genetic structure and reproductive patterns of Pst populations in Ili, Xinjiang, using [...] Read more.

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is a globally significant fungal disease that seriously threatens wheat yield, particularly in China. This study investigates the genetic structure and reproductive patterns of Pst populations in Ili, Xinjiang, using 12 pairs of Simple Sequence Repeat (SSR) molecular markers. Analyses of 79 Pst isolates from either spring or winter wheat areas in Ili revealed three primary genetic clusters, indicating notable differences between populations associated with spring and winter wheat. The STRUCTURE results, complemented by UPGMA and PCoA analyses, highlight significant genetic diversity within these populations, with evidence of genetic recombination and sexual reproduction in certain areas. Pst populations in Ili exhibit a mixed mode of reproduction, predominantly sexual in Qapqal and Xinyuan D and primarily asexual within the spring wheat populations. The gene flow analysis underscores extensive inter-population communication, which facilitates the spread and adaptation of the pathogen across diverse wheat-growing environments. This study marks the first documentation of sexual reproduction in Pst within Xinjiang, providing new insights into its spread and genetic variation. These findings suggest that sexual reproduction may play a role in the regional adaptation and evolution of Pst, impacting future management strategies for wheat stripe rust in Xinjiang and potentially in broader Central Asian contexts. Full article

(This article belongs to the Special Issue Advances in Plant–Pathogen Interactions: 3rd Edition)

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16 pages, 3919 KiB

Open AccessArticle

Genome-Wide Profiling of bZIP Transcription Factors and FocbZIP11’s Impact on Fusarium TR4 Pathogenicity

by Yanling Xie, Huoqing Huang, Yile Huo, Wenlong Yang, Yuqing Li, Siwen Liu and Chunyu Li

Int. J. Mol. Sci. 2025, 26(4), 1452; https://doi.org/10.3390/ijms26041452 - 9 Feb 2025

Viewed by 955

Abstract

The basic leucine zipper (bZIP) transcription factor (TF) family performs diverse functions in fungal processes, including vegetative growth, nutrient utilization, stress responses, and invasion. Despite their importance, little is known about the bZIP members in Fusarium oxysporum f. sp. cubense tropical race 4 [...] Read more.

The basic leucine zipper (bZIP) transcription factor (TF) family performs diverse functions in fungal processes, including vegetative growth, nutrient utilization, stress responses, and invasion. Despite their importance, little is known about the bZIP members in Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4), a highly virulent banana pathogen. In this study, we systematically identified 17 bZIPs distributed across 10 Foc TR4 chromosomes and classified them into four types based on their protein sequences. Phylogenetic analysis of fungal bZIP TFs revealed that the FocbZIP proteins cluster into 12 groups shared across fungal species. A cis-element analysis showed that each bZIP promoter contains at least one type of stress response-related element. Furthermore, RNA-seq and RT-qPCR analyses of FocbZIP gene expression patterns demonstrated that these genes may serve distinct roles during infection. Notably, the deletion of FocbZIP11 led to reduced vegetative growth, heightened sensitivity to osmotic, oxidative, and cell wall stresses, and diminished virulence toward banana plantlets. Overall, our findings indicate that FocbZIP11 plays a critical role in growth, abiotic stress responses, and virulence in Foc TR4. This study provides a foundation for the further functional characterization of FocbZIP genes, and FocbZIP11 might serve as a promising target for RNA-based biopesticide control of FWB. Full article

(This article belongs to the Special Issue Advances in Plant–Pathogen Interactions: 3rd Edition)

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18 pages, 2973 KiB

Open AccessArticle

Trichoderma longibrachiatum TG1 Colonization and Signal Pathway in Alleviating Salinity and Fusarium pseudograminearum Stress in Wheat

by Solomon Boamah, Shuwu Zhang, Bingliang Xu, Na Zhu and Enchen Li

Int. J. Mol. Sci. 2025, 26(9), 4018; https://doi.org/10.3390/ijms26094018 - 24 Apr 2025

Viewed by 174

Abstract

Fusarium pseudograminearum (Fp) and soil salinity are two types of stress that interact in complex ways, potentially leading to more severe consequences on wheat growth and productivity. However, little is known about the colonization efficiency and the signal pathways of the beneficial Trichoderma [...] Read more.

Fusarium pseudograminearum (Fp) and soil salinity are two types of stress that interact in complex ways, potentially leading to more severe consequences on wheat growth and productivity. However, little is known about the colonization efficiency and the signal pathways of the beneficial Trichoderma longibrachiatum TG1 (TG1) in controlling wheat Fusarium crown rot caused by Fp, and enhancing wheat seedling growth under combined salinity and Fp stresses. Therefore, the present study aims to determine the colonization, phytohormone profile, and signaling pathway in TG1-treated wheat seedlings under salinity and Fp stresses. In a dual culture assay, TG1 exhibited a mycoparasitic effect on Fp growth by coiling, conidial attachment, and parasitism observed under fluorescent microscopy. In addition, TG1 colonized the outermost layers of the wheat seedling roots with biomass consisting of conidia and hyphae. Under 100 mM NaCl stress, the combined TG1+Fp-treated seedlings recorded a control efficacy of 47.01% for the wheat crown rot disease compared with Fp-alone-treated seedlings. The contents of indole-3-acetic acid (IAA), gibberellic acid (GA₃), abscisic acid (ABA) and jasmonic acid (JA) significantly increased by 72.16%, 86.91%, 20.04%, and 50.40%, respectively, in the combined TG1+Fp treatments, whereas the ethylene (ET) content decreased by 39.07% compared with Fp alone at day 14; and 5.07 and 2.78-fold increases in the expression of salicylic acid (SA) signaling pathway genes, such as pathogenesis-related protein 1 (PR1) and isochorismate synthase 1 (ICS1) genes were recorded respectively, in the combined TG1+Fp-treated seedlings compared with the control at day 14. Full article

(This article belongs to the Special Issue Advances in Plant–Pathogen Interactions: 3rd Edition)

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