Verticillium wilt is a highly destructive fungal disease that attacks a broad range of plants, including many major crops. However, the mechanism underlying plant immunity toward Verticillium dahliae is very complex and requires further study. By combining bioinformatics analysis and experimental validation, we investigated plant defence responses against V. dahliae infection in the model plant Arabidopsis thaliana L. A total of 301 increased and 214 decreased differentially abundant proteins (DAPs) between mock and infected wild type (WT) plants were acquired and bioinformatics analyses were then conducted and compared (increased vs decreased) in detail. In addition to the currently known mechanisms, several new clues about plant immunity against V. dahliae infection were found in this study: (1) exosome formation was dramatically induced by V. dahliae attack; (2) tryptophan-derived camalexin and cyanogenic biosynthesis were durably promoted in response to infection; and (3) various newly identified components were activated for hub immunity responses. These new clues provide valuable information that extends the current knowledge about the molecular basis of plant immunity against V. dahliae infection.

Phospholipases As (PLAs) are acyl hydrolases that catalyze the release of free fatty acids in phospholipids and play multiple functions in plant growth and development. The three families of PLAs are: PLA1, PLA2 (sPLA), and patatin-related PLA (pPLA). The diverse functions that pPLAs play in the growth and development of a broad range of plants have been demonstrated by prior studies. Genome-wide analysis of the pPLA gene family and screening of genes for expression verification and gene silencing verification were conducted. Additionally, pollen vitality testing, analysis of the pollen expression pattern, and the detection of POD, SOD, CAT, MDA, and H₂O₂ were performed. In this study, 294 pPLAs were identified from 13 plant species, including 46 GhpPLAs that were divided into three subfamilies (I-III). Expression patterns showed that the majority of GhpPLAs were preferentially expressed in the petal, pistil, anther, and ovule, among other reproductive organs. Particularly, GhpPLA23 and GhpPLA44, were found to be potentially important for the reproductive development of G. hirsutum. Functional validation was demonstrated by VIGS which showed that reduced expression levels of GhpPLA23 and GhpPLA44 in the silenced plants were associated with a decrease in pollen activity. Moreover, a substantial shift in ROS and ROS scavengers and a considerable increase in POD, CAT, SOD, and other physiological parameters was found out in these silenced plants. Our results provide plausibility to the hypothesis that GhpPLA23 and GhpPLA44 had a major developmental impact on cotton reproductive systems. These results also suggest that pPLAs are important for G. hirsutum’s reproductive development and suggest that they could be employed as potential genes for haploid induction. The findings of the present research indicate that pPLA genes are essential for the development of floral organs and sperm cells in cotton. Consequently, this family might be important for the reproductive development of cotton and possibly for inducing the plant develop haploid progeny.

Cotton ( Gossypium barbadense L. and Gossypium hirsutum L.), a major economic crop, suffers severe yield losses due to Verticillium wilt caused by Verticillium dahliae Kleb. Although the lectin receptor‐like protein GbMBL1.1A has been identified as a key activator of hypersensitive cell death in cotton resistance to this pathogen, its downstream defense mechanisms remain unknown. Here, we performed comparative transcriptome analyses between the GbMBL1.1A ‐overexpressing (OE) cotton line and its wild‐type (WT) recipient counterpart (WC) under both normal (non‐infected) and V. dahliae infected conditions. A total of 760 differentially expressed genes (DEGs) were identified by comparing GbMBL1.1A ‐OE and WT cotton lines under normal condition. Upon pathogen infection across three timepoints, the counts of 1679 (1063 up, 616 down) and 1648 (633 up, 1015 down) DEGs were identified uniquely from GbMBL1.1A ‐OE or WT cotton line, respectively, relative to their mock controls. Further analysis of these DEGs revealed three aspects of changes due to GbMBL1.1A overexpression: (1) Pre‐infection priming via selective pattern recognition receptor modulation, mitochondrial cell death activation, and reactive oxygen species antioxidant perturbation under normal condition; (2) Significant enhancement of plant defense against pathogen through the remodeling of immune receptor activity, alteration of signal transduction and regulation, and modulation of secondary metabolic processes, with the most significant alteration occurring in lignin and phenylpropanoid metabolism. (3) Dynamic redox homeostasis regulation through metabolite interconversion enzymes during infection process. Collectively, these findings strengthen the theoretical foundation and provide novel candidate targets for developing improved control strategies to enhance cotton resistance against V. dahliae .

The properties of graphene oxide (GO) against viruses and bacteria have received widespread attention, yet research into its antifungal capabilities remains comparatively scarce. Assessing the inhibitory effect of GO on plant pathogenic fungi is crucial for its application in preventing and managing fungal diseases. Verticillium dahliae represents a quintessential soil-borne fungal pathogen that infiltrates through plant roots and resides within the vascular tissues, leading to devastating wilt diseases. This research endeavored to explore the antimicrobial effect of GO on V. dahliae and to elucidate its underlying molecular mechanisms. Our findings revealed that GO exerted a significant inhibitory impact on mycelial growth and spore germination of V. dahliae . In addition, GO can significantly reduce the infection of V. dahliae on cotton. Biochemical analyses indicated that the DNA, RNA, malondialdehyde (MDA), and protein content within V. dahliae cells were markedly elevated post-GO treatment, underscoring the compromised cell membrane integrity. Transcriptome analysis revealed 1,149 differentially expressed genes (DEGs) during hyphal elongation and 1,078 DEGs in the process of spore germination. The downregulated genes predominantly encoded proteins involved in membrane integrity, such as intrinsic and integral membrane components, as well as proteins with oxidoreductase and transporter activities. Collectively, our data suggest that GO impedes mycelia growth and spore germination of V. dahliae by disrupting cell membrane integrity. This study offers novel perspectives for the development of antifungal agents and more precise clues to discover the mechanism by which GO suppresses the proliferation of V. dahliae . IMPORTANCE: GO could suppress the proliferation of the mycelia and the initiation of spore germination of V. dahliae . In addition, the utilization of GO could mitigate the manifestations of cotton wilt resulting from the infection by V. dahliae . This study offers novel perspectives for the development of antifungal agents and more precise clues to discover the mechanism by which GO inhibits the growth of V. dahliae .

In phytopathogenic fungi, ATG24 has been identified as the first mitophagy receptor and evolutionarily conserved. However, its roles in fungal development and pathogenicity vary among species and necessitate further exploration across more diverse fungal genera. In this study, we dissected the molecular functions and underlying mechanisms of the mitophagy receptor ATG24 homolog in the soilborne hemibiotrophic fungus Verticillium dahliae. VdATG24 contains a PX domain, a BAR domain, and an AIM (Atg8-family Interacting Motif) and is a crucial component for prohibitin-mediated mitophagy triggered by both nitrogen deprivation and a mitophagy-specific activator in V. dahliae. Deletion of VdATG24 inhibited the growth rate, shortened the distance between septa, reduced the spore production, and impacted the microsclerotia formation of V. dahliae, without altering spore morphology or sporulation mode. Assessments of pathogenicity further demonstrated that VdATG24 contributes to fungal virulence through the promotion of host colonization. Mechanistically, we uncovered that ATG24 mediates melanin biosynthesis, facilitates protein secretion during the infection process, and indirectly attenuates host immunity, as evidenced by the identified key components and associated biological processes/pathways via transcriptome analyses and subsequent experimental verification. Our data collectively underscore the pivotal roles and preliminary molecular mechanisms of VdATG24 in modulating hyphal growth, conidiation, microsclerotia formation, and virulence in V. dahliae.