Transcriptome analysis reveals the defense mechanism of cotton against Verticillium dahliae in the presence of the biocontrol fungus Chaetomium globosum CEF-082

Endophytic Bacillus velezensis XS142 is an efficient antagonist for Verticillium wilt of potato

Potato Verticillium wilt (PVW) caused by Verticillium dahliae is a vascular disease, that seriously affects potato (Solanum tuberosum L.) yield and quality worldwide. V. dahliae occupies the vascular bundle and therefore it cannot efficiently be treated with fungicides. Further, the application of these pesticides causes serious environmental problems. Therefore, it is of great importance to find environmentally friendly biological control methods. In this study, bacterial strains were isolated from agricultural lands on which potato had been cultured for 5 years. Five strains with a broad-spectrum antagonistic activity were selected. Among these five strains, Bacillus velezensis XS142 showed the highest antagonistic activity. To study the mechanism of XS142, by which this strain might confer tolerance to V. dahliae in potato, the genome of strain XS142 was sequenced. This showed that its genome has a high level of sequence identity with the model strain B. velezensis FZB42 as the OrthoANI (Average Nucleotide Identity by Orthology) value is 98%. The fungal suppressing mechanisms of this model strain are well studied. Based on the genome comparison it can be predicted that XS142 has the potential to suppress the growth of V. dahliae by production of bacillomycin D, fengycin, and chitinase. Further, the transcriptomes of potatoes treated with XS142 were analyzed and this showed that XS142 does not induce ISR, but the expression of genes encoding peptides with antifungal activity. Here we showed that XS142 is an endophyte. Further, it is isolated from a field where potato had been cultured for several years. These properties give it a high potential to be used, in the future, as a biocontrol agent of PVW in agriculture.

Mechanism of oxalate decarboxylase Oxd_S12 from Bacillus velezensis BvZ45-1 in defence against cotton verticillium wilt

Verticillium wilt, a soilborne vascular disease caused by Verticillium dahliae, strongly affects cotton yield and quality. In this study, an isolated rhizosphere bacterium, designated Bacillus velezensis BvZ45-1, exhibited >46% biocontrol efficacy against cotton verticillium wilt under greenhouse and field conditions. Moreover, through crude protein extraction and mass spectrometry analyses, we found many antifungal compounds present in the crude protein extract of BvZ45-1. The purified oxalate decarboxylase Odx_S12 from BvZ45-1 inhibited the growth of V. dahliae Vd080 by reducing the spore yield, causing mycelia to rupture, spore morphology changes, cell membrane rupture, and cell death. Subsequently, overexpression of Odx_S12 in Arabidopsis significantly improved plant resistance to V. dahliae. Through studies of the resistance mechanism of Odx_S12, V. dahliae was shown to produce oxalic acid (OA), which has a toxic effect on Arabidopsis leaves. Odx_S12 overexpression reduced Arabidopsis OA content, enhanced tolerance to OA, and improved resistance to verticillium wilt. Transcriptomics and quantitative real-time PCR analysis revealed that Odx_S12 promoted a reactive oxygen species burst and a salicylic acid- and abscisic acid-mediated defence response in Arabidopsis. In summary, this study not only identified B. velezensis BvZ45-1 as an efficient biological control agent, but also identified the resistance gene Odx_S12 as a candidate for cotton breeding against verticillium wilt.

Inhibition of Verticillium Wilt in Cotton through the Application of Pseudomonas aeruginosa ZL6 Derived from Fermentation Residue of Kitchen Waste

To isolate and analyze bacteria with Verticillium wilt-resistant properties from the fermentation residue of kitchen wastes, as well as explore their potential for new applications of the residue. A total of six bacterial strains exhibiting Verticillium wilt-resistant capabilities were isolated from the biogas residue of kitchen waste fermentation. Using a polyphasic approach, strain ZL6, which displayed the highest antagonistic activity against cotton Verticillium wilt, was identified as belonging to the Pseudomonas aeruginosa. Bioassay results demonstrated that this strain possessed robust antagonistic abilities, effectively inhibiting V. dahliae spore germination and mycelial growth. Furthermore, P. aeruginosa ZL6 exhibited high temperature resistance (42°C), nitrogen fixation, and phosphorus removal activities. Pot experiments revealed that P. aeruginosa ZL6 fermentation broth treatment achieved a 47.72% biological control effect compared to the control group. Through activity tracking and protein mass spectrometry identification, a neutral metalloproteinase (Nml) was hypothesized as the main virulence factor. The mutant strain ZL6ΔNml exhibited a significant reduction in its ability to inhibit cotton Verticillium wilt compared to the strain P. aeruginosa ZL6. While the inhibitory activities could be partially restored by a complementation of nml gene in the mutant strain ZL6CMΔNml. This research provides a theoretical foundation for the future development and application of biogas residue as biocontrol agents against Verticillium wilt and as biological preservatives for agricultural products. Additionally, this study presents a novel approach for mitigating the substantial amount of biogas residue generated from kitchen waste fermentation.

Bacillus velezensis WB induces systemic resistance in watermelon against Fusarium wilt

BACKGROUND

Our previous findings indicated that Bacillus velezensis WB could control Fusarium wilt by changing the structure of the microbial community in the watermelon rhizosphere. However, there are few studies on its mechanism in the pathogen resistance of watermelon. Therefore, in this study, we determined the mechanism of B. velezensis WB-induced systemic resistance in watermelon against Fusarium wilt through glasshouse pot experiments.

RESULTS

The results showed that B. velezensis WB significantly reduced the incidence and disease index of Fusarium wilt in watermelon. B. velezensis WB can enhance the basal immunity of watermelon plants by: increasing the activity of phenylalanine ammonia-lyase (PAL), peroxidase (POD), superoxide dismutase (SOD) and β-1,3-glucanase; accumulating lignin, salicylic acid (SA) and jasmonic acid (JA); reducing malondialdehyde (MDA) concentrations; and inducing callus deposition in watermelon plant cells. RNA-seq analysis showed that 846 watermelon genes were upregulated and 612 watermelon genes were downregulated in the WF treatment. This process led to the activation of watermelon genes associated with auxin, gibberellin, SA, ethylene and JA, and the expression of genes in the phenylalanine biosynthetic pathway was upregulated. In addition, transcription factors involved in plant resistance to pathogens, such as MYB, NAC and WRKY, were induced. Gene correlation analysis showed that Cla97C10G195840 and Cla97C02G049930 in the phenylalanine biosynthetic pathway, and Cla97C02G041360 and Cla97C10G197290 in the plant hormone signal transduction pathway showed strong correlations with other genes.

CONCLUSION

Our results indicated that B. velezensis WB is capable of inducing systemic resistance in watermelon against Fusarium wilt. © 2023 Society of Chemical Industry.

GhTLP1, a thaumatin-like protein 1, improves Verticillium wilt resistance in cotton via JA, ABA and MAPK signaling pathway-plant pathways

Verticillium wilt of cotton is a very serious soil-borne disease and there is no effective control method. The mechanism of Gossypium hirsutum thaumatin-like protein 1(GhTLP1) in upland cotton regulating Verticillium wilt resistance has been an uncovered research approach. GhTLP1 is mainly localized in the cell wall. Overexpression of GhTLP1 significantly enhanced Arabidopsis plants resistance to Verticillium dahliae, while its homologous mutant tlp1 in Arabidopsis was more susceptible to the pathogen, and the heterologous complement line (EC) recovered resistance to V. dahliae. GhTLP1 responds to jasmonate acid (JA) and abscisic acid (ABA) hormones and regulates mitogen-activated protein kinase (MAPK) signaling pathway-plant pathway to enhance Arabidopsis plants resistance to V. dahliae. Silencing GhTLP1 resulted decrease in cotton plants resistance to V. dahliae. Moreover, the mutation of GhTLP1 at site Tyr97 and Tyr199 with the phosphorylation also decreased plant resistance to V. dahliae. Therefore, GhTLP1 phosphorylation was observed important in cotton plants against V. dahliae. Further analysis demonstrated that GhTLP1 interacted with gossypium hirsutum laccase 14 (GhLAC14) to enhance plants resistance to V. dahliae. Silencing GhLAC14 resulted decrease in cotton plants resistance to V. dahliae. Here, we propose that GhTLP1 is a potential molecular target for improving resistance to Verticillium wilt in cotton.

VdPT1 Encoding a Neutral Trehalase of Verticillium dahliae Is Required for Growth and Virulence of the Pathogen

Verticillum dahliae is a soil-borne phytopathogenic fungus causing destructive Verticillium wilt disease. We previously found a trehalase-encoding gene (VdPT1) in V. dahliae being significantly up-regulated after sensing root exudates from a susceptible cotton variety. In this study, we characterized the function of VdPT1 in the growth and virulence of V. dahliae using its deletion-mutant strains. The VdPT1 deletion mutants (ΔVdPT1) displayed slow colony expansion and mycelial growth, reduced conidial production and germination rate, and decreased mycelial penetration ability and virulence on cotton, but exhibited enhanced stress resistance, suggesting that VdPT1 is involved in the growth, pathogenesis, and stress resistance of V. dahliae. Host-induced silencing of VdPT1 in cotton reduced fungal biomass and enhanced cotton resistance against V. dahliae. Comparative transcriptome analysis between wild-type and mutant identified 1480 up-regulated and 1650 down-regulated genes in the ΔVdPT1 strain. Several down-regulated genes encode plant cell wall-degrading enzymes required for full virulence of V. dahliae to cotton, and down-regulated genes related to carbon metabolism, DNA replication, and amino acid biosynthesis seemed to be responsible for the decreased growth of the ΔVdPT1 strain. In contrast, up-regulation of several genes related to glycerophospholipid metabolism in the ΔVdPT1 strain enhanced the stress resistance of the mutated strain.

Integrated microbiology and metabolomics analysis reveal responses of cotton rhizosphere microbiome and metabolite spectrum to conventional seed coating agents

Fludioxonil (FL) and metalaxyl-M·fludioxonil·azoxystrobin (MFA) are conventional seed coating agents for controlling cotton seedling diseases. However, their effects on seed endophytic and rhizosphere microecology are still poorly understood. This study aimed to assess the effects of FL and MFA on cotton seed endophytes, rhizosphere soil enzymatic activities, microbiome and metabolites. Both seed coating agents significantly changed seed endophytic bacterial and fungal communities. Growing coated seeds in the soils originating from the Alar (AL) and Shihezi (SH) region inhibited soil catalase activity and decreased both bacterial and fungal biomass. Seed coating agents increased rhizosphere bacterial alpha diversity for the first 21 days but decreased fungal alpha diversity after day 21 in the AL soil. Seed coating reduced the abundance of a number of beneficial microorganisms but enriched some potential pollutant-degrading microorganisms. Seed coating agents may have affected the complexity of the co-occurrence network of the microbiome in the AL soil, reducing connectivity, opposite to what was observed in the SH soil. MFA had more pronounced effects on soil metabolic activities than FL. Furthermore, there were strong links between soil microbial communities, metabolites and enzymatic activities. These findings provide valuable information for future research and development on application of seed coatings for disease management.

Genome-wide identification and expression analysis of the cyclic nucleotide-gated ion channel (CNGC) gene family in Saccharum spontaneum

BACKGROUND

Cyclic nucleotide-gated ion channels (CNGCs) are nonselective cation channels that are ubiquitous in eukaryotic organisms. As Ca²⁺ channels, some CNGCs have also proven to be K⁺-permeable and involved in plant development and responses to environmental stimuli. Sugarcane is an important sugar and energy crop worldwide. However, reports on CNGC genes in sugarcane are limited.

RESULTS

In this study, 16 CNGC genes and their alleles were identified from Saccharum spontaneum and classified into 5 groups based on phylogenetic analysis. Investigation of gene duplication and syntenic relationships between S. spontaneum and both rice and Arabidopsis demonstrated that the CNGC gene family in S. spontaneum expanded primarily by segmental duplication events. Many SsCNGCs showed variable expression during growth and development as well as in tissues, suggesting functional divergence. Light-responsive cis-acting elements were discovered in the promoters of all the identified SsCNGCs, and the expression of most of the SsCNGCs showed a diurnal rhythm. In sugarcane, the expression of some SsCNGCs was regulated by low-K⁺ treatment. Notably, SsCNGC13 may be involved in both sugarcane development and its response to environmental stimuli, including response to low-K⁺ stress.

CONCLUSION

This study identified the CNGC genes in S. spontaneum and provided insights into the transcriptional regulation of these SsCNGCs during development, circadian rhythm and under low-K⁺ stress. These findings lay a theoretical foundation for future investigations of the CNGC gene family in sugarcane.

The effects and interrelationships of intercropping on Cotton Verticillium wilt and soil microbial communities

BACKGROUND

Cotton Verticillium wilt, causing by Verticillium dahliae, has seriously affected the yield and quality of cotton. The incidence of Verticillium wilt in cotton fields has been on the rise for many years, especially after straw has been returned to the fields. Intercropping can reduce the incidence of soil borne diseases and is often used to control crop diseases, but the relationship between the effects of intercropping on microbial communities and the occurrence of plant diseases is unclear. This research explored the relationship between soil microbial community structure and Cotton Verticillium wilt in interplanting of cotton-onion, cotton-garlic, cotton-wheat and cotton monocultures. Amplicon sequencing applied to the profile of bacterial and fungal communities.

RESULTS

The results showed that the disease index of Cotton Verticillium wilt was significantly reduced after intercropping with cotton-garlic and cotton-onion. Chao1 and Sobs indices were not significantly different in the rhizosphere soil and pre-plant soils of the four planting patterns, but the pre-plant fungal shannon index was significantly lower in the cotton-onion intercropping plot than in the other three plots. PCoA analysis showed that the soil microbial communities changed to a certain extent after intercropping, with large differences in the microbial communities under different cropping patterns. The abundance of Chaetomium was highest in the cotton-garlic intercropping before planting; the abundance of Penicillium was significantly higher in the cotton-wheat intercropping than in the other three systems.

CONCLUSION

Cotton-garlic and cotton-onion interplanting can control Cotton Verticillium wilt by affecting the soil microbial community. Fungi of the genera Chaetomium and Penicillium may be associated with plant disease resistance.

Effect of volatile compounds produced by the cotton endophytic bacterial strain Bacillus sp. T6 against Verticillium wilt

BACKGROUND

Verticillium wilt, caused by the fungus Verticillium dahliae, leads to significant losses in cotton yield worldwide. Biocontrol management is a promising means of suppressing verticillium wilt. The purpose of the study was to obtain and analyze endophytic bacteria with Verticillium wilt-resistant activities from the roots of Gossypium barbadense 'Xinhai15' and to explore the interactions between the soil and plants.

RESULTS

An endophytic bacterium Bacillus sp. T6 was obtained from the Verticillium wilt-resistant cotton G. barbadense 'Xinhai15', which showed significant antagonistic abilities against cotton Verticillium wilt. The bioassay results indicated that the strain possessed strong antagonistic abilities that inhibited V. dahliae spore germination and mycelial growth without contact, and thus it was speculated that the active factor of the bacteria might be volatile compounds. A total of 46 volatile substances were detected via headspace solid-phase microextraction and gas chromatography-mass spectrometry analysis. The pure product verification experiment confirmed that the styrene produced by the T6 strain was the main virulence factor. Transcriptome analysis showed that following styrene induction, 247 genes in V. dahliae, including four hydrolase genes, eight dehydrogenase genes, 11 reductase genes, 17 genes related to transport and transfer were upregulated. Additionally, 72 genes, including two chitinase genes, two protease genes, five transport-related genes, and 33 hypothetical protein genes, were downregulated. The quantitative real-time PCR results confirmed that the expression of the four genes VDAG_02838, VDAG_09554, VDAG_045572, and VDAG_08251 was increased by 3.18, 78.83, 2.71, and 2.92 times, respectively, compared with the uninduced control group.

CONCLUSIONS

The research provides a new reference for the development and application of the volatile compounds of endophytic bacteria as new biocontrol agents for the control of Verticillium wilt and as biological preservatives for agricultural products.

Composition and characteristics of soil microbial communities in cotton fields with different incidences of Verticillium wilt

Soil microorganisms could affect the growth of plants and play an important role in indicating the change of soil environment. Cotton Verticillium wilt is a serious soil borne disease. This study aimed to analyze the community characteristics of soil microorganisms in cotton fields with different incidences of Verticillium wilt, so as to provide theoretical guidance for the prevention and control of soil borne diseases of cotton. Through the analysis of soil microbial communities in six fields, the results showed that there was no difference in fungal and bacterial alpha-diversity index before cotton planting, while there were differences in rhizosphere of diseased plants. For fungal beta diversity indexes, there were significant differences in these six fields. There was no significant difference for bacterial beta diversity indexes before cotton planting, while there was a certain difference in the rhizosphere of diseased cotton plants. The composition of fungi and bacteria in different fields was roughly the same at the genus level, but the abundances of the same genus varied greatly between different fields. Before cotton planting, there were 61 fungi (genera) and 126 bacteria (genera) with different abundances in the six fields. Pseudomonas, Sphingomonas and Burkholderia had higher abundances in the fields with less incidence. This study will provide a theoretical basis for microbial control of Cotton Verticillium wilt.

Broad-spectrum resistance mechanism of serine protease Sp1 in Bacillus licheniformis W10 via dual comparative transcriptome analysis

Antagonistic microorganisms are considered to be the most promising biological controls for plant disease. However, they are still not as popular as chemical pesticides due to complex environmental factors in the field. It is urgent to exploit their potential genetic characteristics and excellent properties to develop biopesticides with antimicrobial substances as the main components. Here, the serine protease Sp1 isolated from the Bacillus licheniformis W10 strain was confirmed to have a broad antifungal and antibacterial spectrum. Sp1 treatment significantly inhibited fungal vegetative growth and damaged the structure of hyphae, in accordance with that caused by W10 strain. Furthermore, Sp1 could activate the systemic resistance of peach twigs, fruits and tobacco. Dual comparative transcriptome analysis uncovered how Sp1 resisted the plant pathogenic fungus Phomopsis amygdali and the potential molecular resistance mechanisms of tobacco. In PSp1 vs. P. amygdali, RNA-seq identified 150 differentially expressed genes (DEGs) that were upregulated and 209 DEGs that were downregulated. Further analysis found that Sp1 might act on the energy supply and cell wall structure to inhibit the development of P. amygdali. In TSp1 vs. Xanthi tobacco, RNA-seq identified that 5937 DEGs were upregulated and 2929 DEGs were downregulated. DEGs were enriched in the metabolic biosynthesis pathways of secondary metabolites, plant hormone signal transduction, plant–pathogen interactions, and MAPK signaling pathway–plant and further found that the genes of salicylic acid (SA) and jasmonic acid (JA) signaling pathways were highly expressed and the contents of SA and JA increased significantly, suggesting that systemic resistance induced by Sp1 shares features of SAR and ISR. In addition, Sp1 might induce the plant defense responses of tobacco. This study provides insights into the broad-spectrum resistance molecular mechanism of Sp1, which could be used as a potential biocontrol product.

Biocontrol Potential of Trichoderma afroharzianum TM24 Against Grey Mould on Tomato Plants

Grey mould caused by Botrytis cinerea leads to severe economic loss on commercial tomato production. Application of beneficial microorganism offers an eco-friendly alternative for mitigation of tomato fungal disease damage, considering negative influences of fungicides. In the present study, an antagonistic Trichoderma afroharzianum isolate TM24 was evaluated for its biocontrol potential on tomato grey mould. The isolate TM24 showed obviously antagonistic effect on B. cinerea mycelium growth and production of glucanase and chitinase. Leaf spraying with spore suspension of isolate TM24 showed a biocontrol efficiency of over 54% against tomato grey mould in greenhouse pot experiment. The activities of plant defense-related enzymes including polyphenol oxidase, phenylalanine ammonialyase, superoxide dismutase, and peroxidase were all increased to varying degrees in tomato leaves after isolate TM24 treatment. Transcriptome analysis showed that, a total of 1941, 1753 and 38 differentially expressed genes (DEGs) were obtained at 24, 48 and 72 hpi, respectively, in tomato leaves pretreated with T. afroharzianum TM24, and then challenged with B. cinerea inoculation. The DEGs were mainly enriched in MAPK signaling pathway and plant hormones signal transduction pathway. Multiple genes that regulated crucial nodes of defense-related pathways, like flavonoid, phenylpropanoid, jasmonic acid and ethylene metabolisms were also identified, which may have positive correlations with the biocontrol potential of isolate TM24 in tomato plants. These promising results provided valuable information on using T. afroharzianum TM24 as a beneficial biocontrol agent in tomato grey mould management.

The use of ribosome-nascent chain complex-seq to reveal the translated mRNA profile and the role of ASN1 in resistance to Verticillium wilt in cotton

We combined traditional mRNA-seq and RNC-seq together to reveal post-transcriptional regulation events impacting gene expression and interactions between the serious fungal pathogen Verticillium dahliae and a susceptible host, Gossypium hirsutum TM-1. After screening the differentially expressed and translated genes, V. dahliae infection was observed to influence gene transcription and translation in its host. Interestingly, the asparagine synthase (ASN1) gene transcripts increased significantly with the increase of infection time, while the rate of ASN1 protein accumulation in host TM-1 was distinctly lower than that in resistant hosts. We knocked down the ASN1 gene in resistant plants (ZZM2), and found that Verticillium-resistance was significantly reduced upon knockdown of ASN1. Our study revealed both transcriptional and post-transcriptional regulation of gene expression in TM-1 cotton plants infected by V. dahliae, and showed that ASN1 functions in the V. dahliae resistance process. These insights support breeding of disease resistance in cotton.

Antifungal Activity of Chaetoviridin A from Chaetomium globosum CEF-082 Metabolites Against Verticillium dahliae in Cotton

Cotton Verticillium wilt (CVW) is a severe soilborne disease caused by the pathogen Verticillium dahliae, and it has a great impact on cotton production. Previous studies found that the biocontrol agent Chaetomium globosum CEF-082 and its metabolic filtrate could reduce the incidence of CVW; however, the underlying mechanism remains unclear. The metabolic crude extract of CEF-082 increased the sensitivity of V. dahliae to stress, degraded the cell wall of V. dahliae, and increased the emergence and plant height of cotton. Through separation and purification of the metabolic crude extract of CEF-082, chaetoviridin A was identified and found to be highly active against V. dahliae. The compound caused cell necrosis and mycelial deformation, increased the production of reactive oxygen species and nitrous oxide, and inhibited the germination of microsclerotia of V. dahliae, enhancing the cotton plant defense response. In addition, CEF-082 also colonized cotton plants.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

The Role of a New Compound Micronutrient Multifunctional Fertilizer against Verticillium dahliae on Cotton

Verticillium dahliae Kleb., the causal pathogen of vascular wilt, can seriously reduce the yield and quality of many crops, including cotton (Gossypium hirsutum). To control the harm caused by V. dahliae, considering the environmental pollution of chemical fungicides and their residues, the strategy of plant nutrition regulation is becoming increasingly important as an eco-friendly method for disease control. A new compound micronutrient fertilizer (CMF) found in our previous study could reduce the damage of cotton Verticillium wilt and increase yield. However, there is little information about the mode of action of CMF to control this disease. In the present study, we evaluated the role of CMF against V. dahliae and its mechanism of action in vitro and in vivo. In the laboratory tests, we observed that CMF could inhibit hyphal growth, microsclerotia germination, and reduce sporulation of V. dahliae. Further studies revealed that the biomass of V. dahliae in the root and hypocotyl of cotton seedlings treated with CMF were significantly reduced compared with the control, and these results could explain the decline in the disease index of cotton Verticillium wilt. Furthermore, those key genes involved in the phenylpropanoid metabolism pathway, resistance-related genes defense, and nitric oxide signaling pathway were induced in cotton root and hypocotyl tissue when treated with CMF. These results suggest that CMF is a multifaceted micronutrient fertilizer with roles in inhibiting the growth, development, and pathogenicity of V. dahliae and promoting cotton growth.

Opportunities and Challenges in Studies of Host-Pathogen Interactions and Management of Verticillium dahliae in Tomatoes

Tomatoes (Solanum lycopersicum L.) are a valuable horticultural crop that are grown and consumed worldwide. Optimal production is hindered by several factors, among which Verticillium dahliae, the cause of Verticillium wilt, is considered a major biological constraint in temperate production regions. V. dahliae is difficult to mitigate because it is a vascular pathogen, has a broad host range and worldwide distribution, and can persist in soil for years. Understanding pathogen virulence and genetic diversity, host resistance, and plant-pathogen interactions could ultimately inform the development of integrated strategies to manage the disease. In recent years, considerable research has focused on providing new insights into these processes, as well as the development and integration of environment-friendly management approaches. Here, we discuss the current knowledge on the race and population structure of V. dahliae, including pathogenicity factors, host genes, proteins, enzymes involved in defense, and the emergent management strategies and future research directions for managing Verticillium wilt in tomatoes.