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Fusarium wilt, caused by the soilborne fungal pathogen Fusarium oxysporum f. sp. lactucae (FOL), is an economically important disease of lettuce (Lactuca sativa) throughout the world. Four pathogenic races of FOL are reported, though only race 1 is known to exist in the United States. Recently, Californian lettuce growers have expressed increasing concern about Fusarium wilt, as some race 1‐resistant cultivars have exhibited susceptibility, and some susceptible cultivars have displayed reduced disease severity. To determine whether such changes in disease patterns are responses to potentially novel variants, we collected infected plants from commercial fields in the Salinas Valley and Santa Maria regions, isolated the fungus, and conducted a series of pathogenicity tests using a set of FOL race differential cultivars over 2 years (2022 and 2023) in controlled conditions. Pathogenicity tests revealed two new FOL variants that elicited novel disease reaction patterns on the set of differential cultivars that have not been previously described. Isolates Fol621 and Fol621s were less aggressive on race 1‐susceptible Banchu Red Fire, designated Variant‐1. Isolate VSP‐0916 incited severe Fusarium wilt on race 1‐resistant Costa Rica No. 4, designated Variant‐2. Moreover, VSP‐0916 exhibited high aggressiveness and the ability to induce disease in other race 1‐resistant cultivars. This study is the first documentation, to our knowledge, of the occurrence of FOL‐inciting Fusarium wilt on race 1‐resistant lettuce in the United States. Our work provides valuable information critical for the development of Fusarium wilt management strategies, including broad‐spectrum resistance breeding efforts against multiple FOL races. [ABSTRACT FROM AUTHOR]

Melon is an important cash crop grown worldwide, with China leading the world in melon acreage. Melon wilt is becoming more common as the area under melon cultivation gradually increases. Therefore, it is crucial to understand the resistance pattern of Fusarium wilt in melons. In this work, among the four test melon cultivars, YG was highly resistant to Fusarium wilt and 1455 was disease‐resistant. However, 5657 was susceptible, while 5455 was highly susceptible to the disease. We detected 71,852 differentially expressed genes in 16 combinations, including 37,382 with up‐regulation and 3470 with down‐regulation, and we investigated 11 genes associated with resistance to Fusarium wilt through bioinformatics and transcriptome analysis. We identified two differentially expressed cinnamyl alcohol dehydrogenases (CAD) that were down‐regulated in the susceptible melon material in contrast to the resistant variety. Nine chitinase (CHT) genes were differentially expressed, with four showing up‐regulation and four showing down‐regulation in the susceptible compared to the resistant melon material. The MeloCHT genes were located on chromosomes 2, 6, 8, 11 and 12, with four of them on chromosome 8. MeloCAD1 was located on chromosome 1 and MeloCAD2 on chromosome 8. The physicochemical properties of the encoded proteins were predicted by bioinformatics, including theoretical isoelectric point, instability coefficient, relative molecular mass, lipid solubility index and hydrophilicity index. The genes encode proteins with α‐helix, extended strand, random coils and β‐turns. This study provides fundamental knowledge on the transcriptome of melons and establishes a foundation for future research on the detection and application of Fusarium wilt‐resistant genes in melons. [ABSTRACT FROM AUTHOR]

Introduction: Fusarium wilt, caused by Fusarium oxysporum f. sp. cubense (Foc), poses a significant global threat to banana cultivation. Conventional methods of disease management are increasingly challenged, thus making it necessary to explore alternative strategies. Bacterial endophytes, particularly from resistant genotypes, are gaining attention as potential biocontrol agents. Sphingobacterium thalpophilum, isolated from the resistant banana cultivar Pisang lilin (JALHSB010000001-JALHSB010000029), presents an intriguing prospect for combating Fusarium wilt. However, its underlying biocontrol mechanisms remain poorly understood. This study aimed to elucidate the antifungal efficacy of S. thalpophilum NMS02 S296 against Foc and explore its biocontrol mechanisms at the genomic level. Methods: Whole genome sequencing of S. thalpophilum NMS02 S296 was conducted using next-generation sequencing technologies and bioinformatics analyses were performed to identify genes associated with antifungal properties. In vitro assays were used to assess the inhibitory effects of the bacterial isolate on the mycelial growth of Foc. To explore the biomolecules responsible for the observed antagonistic activity, metabolites diffused into the agar at the zone of inhibition between Foc S16 and S. thalpophilum NMS02 S296 were extracted and identified. Results: Whole genome sequencing revealed an array of genes encoding antifungal enzymes and secondary metabolites in S. thalpophilum NMS02 S296. In vitro experiments demonstrated significant inhibition of Foc mycelial growth by the bacterial endophyte. Comparative genomic analysis highlighted unique genomic features in S. thalpophilum linked to its biocontrol potential, setting it apart from other bacterial species. Discussion: The study underscores the remarkable antifungal efficacy of S. thalpophilum NMS02 S296 against Fusarium wilt. The genetic basis for its biocontrol potential was elucidated through whole genome sequencing, shedding light on the mechanisms behind its antifungal activity. This study advanced our understanding of bacterial endophytes as biocontrol agents and offers a promising avenue for plant growth promotion towards sustainable strategies to mitigate Fusarium wilt in banana cultivation. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium spp.) is the most important fibre crop worldwide. Black root rot and Fusarium wilt are two major diseases of cotton caused by soil-borne Berkeleyomyces rouxiae and Fusarium oxysporum f. sp. vasinfectum (Fov), respectively. Phenotyping plant symptoms caused by soil-borne pathogens has always been a challenge. To increase the uniformity of infection, we adapted a seedling screening method that directly uses liquid cultures to inoculate the plant roots and the soil. Four isolates, each of B. rouxiae and Fov, were collected from cotton fields in Australia and were characterised for virulence on cotton under controlled plant growth conditions. While the identities of all four B. rouxiae isolates were confirmed by multilocus sequencing, only two of them were found to be pathogenic on cotton, suggesting variability in the ability of isolates of this species to cause disease. The four Fov isolates were phylogenetically clustered together with the other Australian Fov isolates and displayed both external and internal symptoms characteristic of Fusarium wilt on cotton plants. Furthermore, the isolates appeared to induce varied levels of plant disease severity indicating differences in their virulence on cotton. To contrast the virulence of the Fov isolates, four putatively non-pathogenic Fusarium oxysporum (Fo) isolates collected from cotton seedlings exhibiting atypical wilt symptoms were assessed for their ability to colonise cotton host. Despite the absence of Secreted in Xylem genes (SIX6, SIX11, SIX13 and SIX14) characteristic of Fov, all four Fo isolates retained the ability to colonise cotton and induce wilt symptoms. This suggests that slightly virulent strains of Fo may contribute to the overall occurrence of Fusarium wilt in cotton fields. Findings from this study will allow better distinction to be made between plant pathogens and endophytes and allow fungal effectors underpinning pathogenicity to be explored. [ABSTRACT FROM AUTHOR]

Wilt and stem rot (WSR) is an emerging syndrome threatening cut lisianthus (Eustoma russellianum) production in Lam Dong province, Vietnam. The disease was observed in all 13 inspected commercial lisianthus greenhouses across major lisianthus cultivation areas in Lam Dong, including Da Lat, Lac Duong, Don Duong, and Duc Trong, with incidence increasing with plant age, ranging from 7.5 to 32.4%. Infected plants displayed stunting, wilting, stem rot and blight, and dieback, with predominance of wilt and stem rot. The disease showed polycyclic behavior, with symptoms shifting from random or scattered in young plants to clustered patterns after the initial flower cutting. Forty-one Fusaria-like fungal isolates recovered from diseased lisianthus plants were identified as Fusarium vanleeuwenii (28 isolates), Neocosmospora solani (11 isolates), and F. annulatum (2 isolates) based on morphological observations and phylogenetic analysis of the internal transcribed spacer (ITS) region and translation elongation factor 1-alpha (TEF-1α) genes. The composition of Fusaria species varied across sites, with F. vanleeuwenii being consistently present. Pathogenicity tests confirmed that isolates of F. vanleeuwenii Li-Fo9511, N. solani Li-Fs4311, and F. annulatum Li-Fp3051 caused typical stem rot in in-vitro assays. In-planta assays showed wilting in seedlings starting two weeks post-infection, with a remarkable increase in disease incidence and severity between five and six weeks, particularly for F. vanleeuwenii Li-Fo9511. The pathogens were re-isolated and morphologically confirmed, fulfilling Koch’s postulates. This is the first report of F. vanleeuwenii, N. solani, and F. annulatum as pathogens of lisianthus WSR in Vietnam, highlighting the need for effective control strategies. [ABSTRACT FROM AUTHOR]

Fusarium oxysporum is one of the most economically important plant fungal pathogens, causing devastating Fusarium wilt diseases on a diverse range of hosts, including many key crop plants. Consequently, F. oxysporum has been the subject of extensive research to help develop and improve crop protection strategies. The sequencing of the F. oxysporum genome 14 years ago has greatly accelerated the discovery and characterization of key genes contributing to F. oxysporum biology and virulence. In this review, we summarize important findings on the molecular mechanisms of F. oxysporum growth, reproduction, and virulence. In particular, we focus on genes studied through mutant analysis, covering genes involved in diverse processes such as metabolism, stress tolerance, sporulation, and pathogenicity, as well as the signaling pathways that regulate them. In doing so, we hope to present a comprehensive review of the molecular understanding of F. oxysporum that will aid the future study of this and related species. [ABSTRACT FROM AUTHOR]

The intensified concerns related to agrochemicals' ecological and health risks have encouraged the exploration of microbial agents as eco-friendly alternatives. Some members of Bacillus spp. are potential plant-growth-promoting agents and benefit numerous crop plants globally. This study aimed to explore the beneficial effects of two Bacillus strains (B. subtilis strain IS1 and B. amyloliquificiens strain IS6) capable of alleviating the growth of tomato plants against salinity stress and Fusarium wilt disease. These strains were able to significantly promote the growth of tomato plants and biomass accumulation in pot trials in the absence of any stress. Under salinity stress conditions (150 mM NaCl), B. subtilis strain IS1 demonstrated superior performance and significantly increased shoot length (45.74%), root length (101.39%), fresh biomass (62.17%), and dry biomass (49.69%) contents compared to control plants. Similarly, B. subtilis strain IS1 (63.7%) and B. amyloliquificiens strain IS6 (32.1%) effectively suppressed Fusarium wilt disease and significantly increased plant growth indices compared to the pathogen control. Furthermore, these strains increased the production of chlorophyll, carotenoid, and total phenolic contents. They significantly affected the activities of enzymes involved in antioxidant machinery and the phenylpropanoid pathway. Hence, this study effectively demonstrates that these Bacillus strains can effectively alleviate the growth of tomato plants under multiple stress conditions and can be used to develop bio-based formulations for use in the fields. [ABSTRACT FROM AUTHOR]

Fusarium wilt, caused by Fusarium oxysporum f. sp. spinaciae, causes a significant challenge on vegetative spinach and seed production. Addressing this issue necessitates continuous research focused on innovative treatments and protocols through comprehensive bioassays. Recent studies have highlighted the potential of plant-based compounds in controlling fungal diseases. The present work aims to conduct a series of experiments, encompassing both in vitro and in planta assessments, to investigate the biocontrol capabilities of different essential oils (EOs) at various application rates, with the ultimate goal of reducing the incidence of Fusarium wilt in spinach. The inhibitory effect of four plant EOs (marjoram, thyme, oregano, and tea tree) was initially assessed on the spore germination of five unknown Fusarium strains. The outcomes revealed diverse sensitivities of Fusarium strains to EOs, with thyme exhibiting the broadest inhibition, followed by oregano at the highest concentration (6.66 μL/mL) in most strains. The tested compounds displayed a diverse range of median effective dose (ED50) values (0.69 to 7.53 µL/mL), with thyme and oregano consistently showing lower ED50 values. The direct and indirect inhibitory impact of these compounds on Fusarium mycelial growth ranged from -14% to -100%, wherein thyme and oregano consistently exhibiting the highest effectiveness. Following the results of five distinct inoculation approaches and molecular identification, the highly pathogenic strain F-17536 (F. oxysporum f.sp. spinaciae) was chosen for Fusarium wilt assessment in spinach seedlings, employing two promising EO candidates through seed and soil treatments. Our findings indicate that colonized grain (CG) proved to be a convenient and optimal inoculation method for consistent Fusarium wilt assessment under greenhouse conditions. Seed treatments with thyme and oregano EOs consistently resulted in significantly better disease reduction rates, approximately 54% and 36% respectively, compared to soil treatments (P > 0.05). Notably, thyme, applied at 6.66 µL/mL, exhibited a favorable emergence rate (ERI), exceeding seven, in both treatments, emphasizing its potential for effective disease control in spinach seedlings without inducing phytotoxic effects. This study successfully transitions from in vitro to in planta experiments, highlighting the potential incorporation of EOs into integrated disease management for Fusarium wilt in spinach production. [ABSTRACT FROM AUTHOR]

Fusarium‐induced wilt significantly affects the cultivation and yield of pigeon peas. This warrants sustainable disease management while promoting plant growth. The present study investigated the biopotential of coinoculation of Streptomyces pseudogriseolus S‐9 and Rhizophagus irregularis for plant growth promotion and mitigation of the impact of Fusarium wilt on pigeon pea over three seasons at pot and field levels. Pigeon pea plants were subjected to Fusarium wilt stress and treated with different inoculation strategies, including single and combined applications of S. pseudogriseolus S‐9 and R. irregularis. Plant growth parameters and yields were assessed to evaluate the efficacy of the coinoculation. In the pot experiment, T‐6 treatment resulted in the longest root (62.56 ± 0.01 cm) and shoot (70.24 ± 0.01 cm) lengths compared to the application of commercial biofungicide T‐8 (Trichoderma). This treatment also significantly influenced the yield of potted plants. It resulted in the highest fresh root weight (62.27 ± 0.01 g), fresh shoot weight (70.24 ± 0.02 g), maximum root (55.25 ± 0.01 g) and shoot dry weights (52.25 ± 0.01 g). In the field experiment, pigeon pea plants treated with the bioinoculant also demonstrated a substantial increase (р ≤ 0.05) in total grain yield, the weight of 100 grains, and the number of filled grains compared to the control group in all experimental seasons. In vitro, antagonism assay of compatibility of mycorrhizae and bacteria showed good activity using powder formulation. Thus, the consortium application inspired the broad application of Streptomyces and Trichoderma as effective bioinoculants for wilt management and yield improvement in pigeon peas. [ABSTRACT FROM AUTHOR]

Panama disease, or Fusarium wilt, is a soil‐borne fungal disease of Musa spp. and the most severe threat to the banana industry and food security worldwide with no cure. Therefore, early detection of the pathogen Fusarium oxysporum f. sp. cubense (Foc) through reliable diagnostics will aid in implementing plant quarantine and containment measures to prevent the spread of this disease. In this study, a primary diagnostic procedure was developed based on the DNA sequences of the Foc‐TR4 SIX8a homologue, extracted from a piece of pseudostem tissue of M. acuminata Gros Michel Subgroup from Japan. A set of primers for the loop‐mediated isothermal amplification (LAMP) reaction was designed. The developed specific marker can be used to accurately, rapidly, and reliably detect early diagnosis of Foc‐TR4 infection without cutting down the unconfirmed young plant in banana fields. [ABSTRACT FROM AUTHOR]

Lentil (Lens culinaris) is an important pulse crop in India. Fusarium wilt caused by Fusarium oxysporum f. sp. lentis (Fol), is a major biotic constraint in lentil production. The present investigation was undertaken to evaluate the efficacy of combination products of fungicides and bio‐agents against Fol under in vitro and in vivo conditions. Fungicides were evaluated using the poisoned food technique, while the antagonistic activity of bio‐agents was studied using dual culture technique. Among seven combination products of fungicides, carbendazim 12% + mancozeb 63% was the most effective fungicide in restricting the colony diameter of the pathogen. In field conditions, the seed treatment with carbendazim 12% + mancozeb 63% at 2.5 g/kg seed performed best in both yield and seed quality parameters. Among the bio‐agents tested, Trichoderma asperullum gave the best results in suppressing pathogen growth under in vitro conditions. The seed treatment with the combination of T. asperullum + Pseudomonas fluorescens at 5 g/kg seed showed improvement in seed yield and seed quality parameters in the field. The present study has provided chemical and biological measures for the integrated management of lentil wilt. [ABSTRACT FROM AUTHOR]

The economic repercussions of Fusarium wilt on global tomato crops underscore the disease's paramount importance. And by employing non-toxic, environmentally friendly ingredients that align with sustainable practices and emphasize biosafety considerations, green synthesis, an emerging field in nanobiotechnology, presents financial and ecological benefits surpassing customary chemical and physical approaches. The main objective of the present investigation is to formulate chitosan nanomolecules laden with Trichoderma harzianum extract and characterize them. Additionally, the study aimed to investigate the antifungal effectiveness of these chitosan nanomolecules towards Fusarium oxysporum f.sp. lycopersici. Employing the ionic gelation technique and tripolyphosphate (TPP), chitosan nanomolecules laden with T. harzianum extract were synthesized. Subsequent characterization involved UV-vis, FTIR, AFM, SEM, XRD, and EDX techniques to demonstrate the effectiveness of the biochemical transformation. In addition, the antifungal efficacy of bio-manufactured chitosan nanomolecules has been assessed against five strongly virulent isolates from F. oxysporum f.sp. lycopersici. The study revealed the highest inhibition rates of growth for all isolates to be 100% at a 1 mg/ml concentration of CNPs. In contrast, the minimal inhibitory level rates at 0.125 mg/ml of CNPs were 32.75, 32.83, 32.85, 36.92, and 41.17%, consecutively. This investigation's findings have revealed a recently discovered biological pathway to biosynthesize chitosan nanomolecules in an environmentally friendly way by using T. harzianum. The confirmed antifungal efficacy of the synthesized CNPs towards F. oxysporum suggests their potential as alternatives to or reducers of widespread fungicide use, applicable across various technical and agricultural domains. [ABSTRACT FROM AUTHOR]

Background: Approximately 90% of the world's chickpea is grown under rainfed conditions where terminal drought is one of the major constraints limiting productivity. The need of short-duration, Fusarium wilt tolerant cultivars/elite lines and able to escape drought due to early maturity were required. Methods: The present investigation was carried out using 54 genotypes, generated from six diverse crosses, along with ten checks (resistant/tolerance, susceptible) were screened against drought and Fusarium wilt at Zonal Agricultural Research Station, Kalaburagi, Karnataka (Latitude: 17.36 and Longitude: 76.82) during crop season 2018-19. Result: The results revealed that higher PCV, GCV, heritability, per cent genetic advance were exhibited by number of pods per plant and seed yield per plot, whereas lower PCV, GCV recorded for days to 50% flowering and days to maturity in both normal and late sown conditions. The advanced breeding lines viz., KCD-8, KCD-24, KCD-28, KCD-32, KCD-37 and KCD-53 were identified as drought tolerant lines based on drought tolerant indices (viz., MP, YSI, DTE and DSI). The lines KCD-48 and KCD-32 were identified as Fusarium wilt resistance with lowest PDI of 1.47 and 2.46 respectively, as they were screened in wilt sick plot and further these were validated and confirmed the resistant alleles using two unpublished SNP markers (FW2_30366110 and FW2_30365816). The advanced breeding lines KCD-32 and KCD-37 were identified as drought tolerant and Fusarium wilt resistant. [ABSTRACT FROM AUTHOR]

Enhancing plants' resistance against FW is crucial for ensuring a sustainable global chickpea production. The present study focuses on the identification of fungal pathogens and the assessment of ninety-six chickpea samples for Fusarium wilt from the International Center for Agricultural Research in the Dry Areas (ICARDA)'s collection. Eight fungal isolates were recovered from the symptomatic chickpeas. Polyphasic identification was conducted by comparing the internal transcribed spacer region (ITS), the elongation factor 1-α (tef1-α), and beta-tubulin (tub2). Among them, Neocosmospora solani, N. nelsonii, N. falciformis, N. brevis, Fusarium brachygibbosum, and F. gossypinum were identified. An analysis of the genetic diversity of chickpeas, using 69 polymorphic simple sequence repeat (SSR) markers, revealed a total of 191 alleles across all markers, with, on average, each SSR marker detecting approximately 2.8 alleles. A STRUCTURE analysis delineated lines into two distinct sub-groups (K = 2). Association mapping, using the generalized linear model (GLM) and mixed linear model (MLM) approaches, identified six and five marker–trait associations (MTAs) for FW resistance, respectively. Notably, these TA42, TA125 (A) and TA125 (B), TA37, and TAASH MTAs, commonly found in both models, emerge as potential candidates for the targeted enhancement of FW resistance in chickpeas. To our knowledge, this study represents an inaugural report on the association mapping of genomic loci governing FW resistance in chickpeas from the ICARDA's accessions. [ABSTRACT FROM AUTHOR]

Deciphering effector genes of plant‐pathogenic fungi is key to understanding their role in pathogenicity because acquisition of such genes through horizontal transfer may result in emergence of new pathogenic races. A full‐length (837 bp) Six1 gene has been cloned and sequenced from the genome of Fusarium oxysporum FPo isolated from roots of wilted potatoes in West Bengal, India. The isolate was identified based on conidial morphology and sequencing of the 28S rDNA and elongation factor 1α gene. Koch's postulates established that the isolate could incite wilting in potato plants. The Six Gene Expression 1 gene (Sge1) was amplified from the isolate and compared with that of other wilt‐causing F. oxysporum isolates. The Six1 gene had no intron and it encoded 278 amino acids, with a calculated molecular weight of 30.6 kDa, estimated isoelectric point 5.66 and theoretical extinction coefficient of 57,410 M−1 cm−1. Multiple sequence alignment of SIX1 amino acid sequences showed that the length of SIX1 varied among F. oxysporum formae speciales and different isolates of the same forma specialis. The predicted secondary structure of FPoSIX1 contained four α‐helices and 14 β‐sheets. Its predicted tertiary structure showed 92% query coverage and 67.37% identity with the template of the SIX1 protein of F. oxysporum f. sp. lycopersici PDB code: 7t69. The QMEAN score of this model was −2.53 and the model was validated using the Ramachandran Phi/Psi plot. Structure analysis of the effector protein will be helpful to identify its specific function and recognition by the host resistance protein. [ABSTRACT FROM AUTHOR]

BACKGROUND: Fusarium infection has caused huge economic losses in many crops. The study aimed to compare the microbial community of suppressive and conducive soils and relate to the reduction of Fusarium wilt. RESULTS: High‐throughput sequencing and microbial network analysis were used to investigate the differences in the rhizosphere microbiota of the suppressive and conducive soils and to identify the beneficial keystone taxa. Plant pathogens were enriched in the conducive soil. Potential plant‐beneficial microorganisms and antagonistic microorganisms were enriched in the suppressive soil. More positive interactions and keystone taxa existed in the suppressive soil network. Thirty‐nine and 16 keystone taxa were identified in the suppressive and conducive soil networks, respectively. Sixteen fungal strains and 168 bacterial strains were isolated from suppressive soil, some of which exhibited plant growth‐promotion traits. Thirty‐nine bacterial strains and 10 fungal strains showed antagonistic activity against F. solani. Keystone taxa Bacillus and Trichoderma exhibited high antifungal activity. Lipopeptides produced by Bacillus sp. RB150 and chitinase from Trichoderma spp. inhibited the growth of F. solani. Microbial consortium I (Bacillus sp. RB150, Pseudomonas sp. RB70 and Trichoderma asperellum RF10) and II (Bacillus sp. RB196, Bacillus sp. RB150 and T. asperellum RF10) effectively controlled root rot disease, the spore number of F. solani was reduced by 94.2% and 83.3%. CONCLUSION: Rhizospheric microbiota of suppressive soil protects plants against F. solani infection. Antagonistic microorganisms in suppressive soil inhibit pathogen growth and infection. Microbial consortia consisted of keystone taxa well control root rot disease. These findings help control Fusarium wilt. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The common bean (Phaseolus vulgaris L.) is a globally cultivated leguminous crop. Fusarium wilt (FW), caused by Fusarium oxysporum f. sp. phaseoli (Fop), is a significant disease leading to substantial yield loss in common beans. Disease-resistant cultivars are recommended to counteract this. The objective of this investigation was to identify single nucleotide polymorphism (SNP) markers associated with FW resistance and to pinpoint potential resistant common bean accessions within a core collection, utilizing a panel of 157 accessions through the Genome-wide association study (GWAS) approach with TASSEL 5 and GAPIT 3. Phenotypes for Fop race 1 and race 4 were matched with genotypic data from 4740 SNPs of BARCBean6K_3 Infinium Bea Chips. After ranking the 157-accession panel and revealing 21 Fusarium wilt-resistant accessions, the GWAS pinpointed 16 SNPs on chromosomes Pv04, Pv05, Pv07, Pv8, and Pv09 linked to Fop race 1 resistance, 23 SNPs on chromosomes Pv03, Pv04, Pv05, Pv07, Pv09, Pv10, and Pv11 associated with Fop race 4 resistance, and 7 SNPs on chromosomes Pv04 and Pv09 correlated with both Fop race 1 and race 4 resistances. Furthermore, within a 30 kb flanking region of these associated SNPs, a total of 17 candidate genes were identified. Some of these genes were annotated as classical disease resistance protein/enzymes, including NB-ARC domain proteins, Leucine-rich repeat protein kinase family proteins, zinc finger family proteins, P-loopcontaining nucleoside triphosphate hydrolase superfamily, etc. Genomic prediction (GP) accuracy for Fop race resistances ranged from 0.26 to 0.55. This study advanced common bean genetic enhancement through marker-assisted selection (MAS) and genomic selection (GS) strategies, paving the way for improved Fop resistance.

Abstract Background Cabbage Fusarium wilt (CFW) is a devastating disease caused by the soil-borne fungus Fusarium oxysporum f. sp. conglutinans (Foc). One of the optimal measures for managing CFW is the employment of tolerant/resistant cabbage varieties. However, the interplay between plant genotypes and the pathogen Foc in shaping the rhizosphere microbial community, and the consequent influence of these microbial assemblages on biological resistance, remains inadequately understood. Results Based on amplicon metabarcoding data, we observed distinct differences in the fungal alpha diversity index (Shannon index) and beta diversity index (unweighted Bray–Curtis dissimilarity) within the rhizosphere of the YR (resistant to Foc) and ZG (susceptible to Foc) cabbage varieties, irrespective of Foc inoculation. Notably, the Shannon diversity shifts in the resistant YR variety were more pronounced following Foc inoculation. Disease-resistant plant variety demonstrate a higher propensity for harboring beneficial microorganisms, such as Pseudomonas, and exhibit superior capabilities in evading harmful microorganisms, in contrast to their disease-susceptible counterparts. Furthermore, the network analysis was performed on rhizosphere-associated microorganisms, including both bacteria and fungi. The networks of association recovered from YR exhibited greater complexity, robustness, and density, regardless of Foc inoculation. Following Foc infection in the YR rhizosphere, there was a notable increase in the dominant bacterium NA13, which is also a hub taxon in the microbial network. Reintroducing NA13 into the soil significantly improved disease resistance in the susceptible ZG variety, by directly inhibiting Foc and triggering defense mechanisms in the roots. Conclusions The rhizosphere microbial communities of these two cabbage varieties are markedly distinct, with the introduction of the pathogen eliciting significant alterations in their microbial networks which is correlated with susceptibility or resistance to soil-borne pathogens. Furthermore, we identified a rhizobacteria species that significantly boosts disease resistance in susceptible cabbages. Our results indicated that the induction of resistance genes leading to varied responses in microbial communities to pathogens may partly explain the differing susceptibilities of the cabbage varieties tested to CFW. Video Abstract

Endophytic fungi are microorganisms known as plant-associated fungi and are typically found asymptomatically inside plant tissue. By directly generating secondary metabolites, endophytic fungi help their host plants grow and become more resistant to plant diseases. Furthermore, they can also biosynthesize bioactive compounds used for antimicrobials, which were previously believed to be produced only by the host plant. Medicinal plants as host plants for endophytic fungi which produce secondary metabolites and their ability as biological agents against pathogens. Calabash tree is a medicinal plant that contains active compounds that function as antifungal and antibacterial. This study aims to determine the antagonistic activity of endophytic fungi from calabash tree leaves against F. oxysporum Fos, the pathogen that causes fusarium wilt in shallot plants. Twelve endophytic fungi were obtained from isolation from the leaves of the calabash tree, namely EnM6C22, EnM11P2, EnM6A2, EnM5H21, EnM10H22, EnM12P, EnM11P, EnM111, EnM5H22, EnM9Pt22, EnM5H1 and EnM5K. Five of the twelve endophytic fungi of calabash tree leaves have been identified, as Fusarium sp., Rhizoctonia sp., Pestalotia sp., Colletotrichum sp., and Bipolaris sp. with inhibition percentages of 36.43%, 32.19%, 25.41%, 32.19%, and 27.53% respectively at 7 days after inoculation.

Abstract Endophytic fungal-based biopesticides are sustainable and ecologically-friendly biocontrol agents of several pests and diseases. However, their potential in managing tomato fusarium wilt disease (FWD) remains unexploited. This study therefore evaluated effectiveness of nine fungal isolates against tomato fusarium wilt pathogen, Fusarium oxysporum f. sp. lycopersici (FOL) in vitro using dual culture and co-culture assays. The efficacy of three potent endophytes that inhibited the pathogen in vitro was assessed against FWD incidence, severity, and ability to enhance growth and yield of tomatoes in planta. The ability of endophytically-colonized tomato (Solanum lycopersicum L.) plants to systemically defend themselves upon exposure to FOL were also assessed through defence genes expression using qPCR. In vitro assays showed that endophytes inhibited and suppressed FOL mycelial growth better than entomopathogenic fungi (EPF). Endophytes Trichoderma asperellum M2RT4, Hypocrea lixii F3ST1, Trichoderma harzianum KF2R41, and Trichoderma atroviride ICIPE 710 had the highest (68.84–99.61%) suppression and FOL radial growth inhibition rates compared to EPF which exhibited lowest (27.05–40.63%) inhibition rates. Endophytes T. asperellum M2RT4, H. lixii F3ST1 and T. harzianum KF2R41 colonized all tomato plant parts. During the in planta experiment, endophytically-colonized and FOL-infected tomato plants showed significant reduction of FWD incidence and severity compared to non-inoculated plants. In addition, these endophytes contributed to improved growth promotion parameters and yield. Moreover, there was significantly higher expression of tomato defence genes in T. asperellum M2RT4 colonized than in un-inoculated tomato plants. These findings demonstrated that H. lixii F3ST1 and T. asperellum M2RT4 are effective biocontrol agents against FWD and could sustainably mitigate tomato yield losses associated with fusarium wilt.

Background: Cabbage Fusarium wilt (CFW) is a devastating disease caused by the soil-borne fungus Fusarium oxysporum f. sp. conglutinans (Foc). One of the optimal measures for managing CFW is the employment of tolerant/resistant cabbage varieties. However, the interplay between plant genotypes and the pathogen Foc in shaping the rhizosphere microbial community, and the consequent influence of these microbial assemblages on biological resistance, remains inadequately understood. Results: Based on amplicon metabarcoding data, we observed distinct differences in the fungal alpha diversity index (Shannon index) and beta diversity index (unweighted Bray–Curtis dissimilarity) within the rhizosphere of the YR (resistant to Foc) and ZG (susceptible to Foc) cabbage varieties, irrespective of Foc inoculation. Notably, the Shannon diversity shifts in the resistant YR variety were more pronounced following Foc inoculation. Disease-resistant plant variety demonstrate a higher propensity for harboring beneficial microorganisms, such as Pseudomonas, and exhibit superior capabilities in evading harmful microorganisms, in contrast to their disease-susceptible counterparts. Furthermore, the network analysis was performed on rhizosphere-associated microorganisms, including both bacteria and fungi. The networks of association recovered from YR exhibited greater complexity, robustness, and density, regardless of Foc inoculation. Following Foc infection in the YR rhizosphere, there was a notable increase in the dominant bacterium NA13, which is also a hub taxon in the microbial network. Reintroducing NA13 into the soil significantly improved disease resistance in the susceptible ZG variety, by directly inhibiting Foc and triggering defense mechanisms in the roots. Conclusions: The rhizosphere microbial communities of these two cabbage varieties are markedly distinct, with the introduction of the pathogen eliciting significant alterations in their microbial networks which is correlated with susceptibility or resistance to soil-borne pathogens. Furthermore, we identified a rhizobacteria species that significantly boosts disease resistance in susceptible cabbages. Our results indicated that the induction of resistance genes leading to varied responses in microbial communities to pathogens may partly explain the differing susceptibilities of the cabbage varieties tested to CFW. -meKq2qaHpqpKck3NvZ8m1 Video Abstract [ABSTRACT FROM AUTHOR]

Introduction: Fusarium wilt (FW) caused by Fusarium oxysporum f. sp. cucumerinum (Foc) is a destructive soil-borne disease in cucumber (Cucumis sativus. L). However, there remains limited knowledge on the molecular mechanisms underlying FW resistance-mediated defense responses in cucumber. Methods: In this study, metabolome and transcriptome profiling were carried out for two FW resistant (NR) and susceptible (NS), near isogenic lines (NILs) before and after Foc inoculation. NILs have shown consistent and stable resistance in multiple resistance tests conducted in the greenhouse and in the laboratory. A widely targeted metabolomic analysis identified differentially accumulated metabolites (DAMs) with significantly greater NR accumulation in response to Foc infection, including many phenolic acid and flavonoid compounds from the flavonoid biosynthesis pathway. Results: Transcriptome analysis identified differentially expressed genes (DEGs) between the NILs upon Foc inoculation including genes for secondary metabolite biosynthesis and transcription factor genes regulating the flavonoid biosynthesis pathway. Joint analysis of the metabolomic and transcriptomic data identified DAMs and DEGs closely associated with the biosynthesis of phenolic acid and flavonoid DAMs. The association of these compounds with NRconferred FW resistance was exemplified by in vivo assays. These assays found two phenolic acid compounds, bis (2-ethylhexyl) phthalate and diisooctyl phthalate, as well as the flavonoid compound gallocatechin 3-O-gallate to have significant inhibitory effects on Foc growth. The antifungal effects of these three compounds represent a novel finding. Discussion: Therefore, phenolic acids and flavonoids play important roles in NR mediated FW resistance breeding in cucumber. [ABSTRACT FROM AUTHOR]

Fusarium wilt (FW) is widespread in global cotton production, but the mechanism underlying FW resistance in superior‐fiber‐quality Sea Island cotton is unclear. This study reveals that FW resistance has been the target of genetic improvement of Sea Island cotton in China since the 2010s. The key nonsynonymous single nucleotide polymorphism (SNP, T/C) of gene Gbar_D03G001670 encoding protein phosphatase 2C 80 (PP2C80) results in an amino acid shift (L/S), which is significantly associated with FW resistance of Sea Island cotton. Silencing GbPP2C80 increases FW resistance in Sea Island cotton, whereas overexpressing GbPP2C80 reduces FW resistance in Arabidopsis. GbPP2C80 and GbWAKL14 exist synergistically in Sea Island cotton accessions with haplotype forms "susceptible–susceptible" (TA) and "resistant–resistant" (CC), and interact with each other. CRISPR/Cas9‐mediated knockout of GbWAKL14 enhances FW and Verticillium wilt (VW) resistance in upland cotton and overexpression of GbWAKL14 and GbPP2C80 weakens FW and VW resistance in Arabidopsis. GbPP2C80 and GbWAKL14 respond to FW and VW by modulating reactive oxygen species (ROS) content via affecting MPK3 expression. In summary, two tandem genes on chromosome D03, GbPP2C80, and GbWAKL14, functions as cooperative negative regulators in cotton wilt disease defense, providing novel genetic resources and molecular markers for the development of resistant cotton cultivars. [ABSTRACT FROM AUTHOR]

Simple Summary: Black soldier fly larvae (BSFL) frass, the residual material resulting from the bioconversion of organic matter by BSFL, is gaining attention as a potential organic amendment for plant growth. Studies have reported the potential of BSFL frass to replace commercial inorganic fertilizers in food crops. Besides improving soil fertility, BSFL frass was recently shown to have antifungal activity against different fungal plant pathogens, suggesting that it could suppress fungal plant diseases. This study investigated the effect of BSFL frass derived from BSFL reared on a diet composed of fruit/vegetable/bakery/brewery residues (FVBB diet) and on the Gainesville diet (GV diet) on the development of Fusarium wilt in tomato plants caused by the fungus Fusarium oxysporum f. sp. lycopersici (FOL). The results show that frass from BSFL reared on the GV diet, treated with heat (70 °C, 1 h) or not, inhibited FOL root colonization and reduced the severity of the disease to a far greater extent than frass from BSFL reared on a FVBB diet and commercial compost made of peat, seaweed, and shrimps. This study suggests that BSFL frass, depending on the larval rearing diet, could serve as a soil amendment to control FOL in tomato plants, opening new avenues of research for the valorization of BSFL frass. This study investigated the effect of black soldier fly larvae (BSFL) frass derived from BSFL reared on a diet composed of fruit/vegetable/bakery/brewery residues (FVBB diet) and on the Gainesville diet (GV diet) on the development of tomato (Solanum lycopersicum) Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici (FOL). Tomato plants were grown in a substrate inoculated with FOL that was amended (10%, v:v) or not (control) with either a commercial compost, pasteurized (70 °C for 1 h) frass from BSFL reared on a FVBB diet, non-pasteurized frass from BSFL reared on a FVBB diet, pasteurized frass from BSFL reared on the GV diet, or non-pasteurized frass from BSFL reared on the GV diet. The results show that frass from BSFL reared on the GV diet, irrespective of pasteurization, inhibited FOL root colonization and reduced the severity of tomato Fusarium wilt to a far greater extent than frass from BSFL reared on a FVBB diet and commercial compost made of peat, seaweed, and shrimps. This study suggests that BSFL frass, depending on the larval rearing diet, has the potential to serve as a pasteurized or non-pasteurized soil amendment with prophylactic properties against FOL in tomato plants, opening new avenues of research for the valorization of BSFL frass. [ABSTRACT FROM AUTHOR]

Chitinase genes, as a class of cell wall hydrolases, are essential for the development and pathogenesis of Fusarium oxysporum f.sp. vasinfectum (F. ox) in cotton, but related research focused on chitinase genes are limited. This study explored two island cotton root secretions from the highly resistant cultivar Xinhai 41 and sensitive cultivar Xinhai 14 to investigate their interaction with F. ox by a weighted correlation network analysis (WGCNA). As a result, two modules that related to the fungal pathogenicity emerged. Additionally, a total of twenty-five chitinase genes were identified. Finally, host-induced gene silencing (HIGS) of FoChi20 was conducted, and the cotton plants showed noticeably milder disease with a significantly lower disease index than the control. This study illuminated that chitinase genes play crucial roles in the pathogenicity of cotton wilt fungi, and the FoChi20 gene could participate in the pathogenesis of F. ox and host–pathogen interactions, which establishes a theoretical framework for disease control in Sea Island cotton. [ABSTRACT FROM AUTHOR]

This study aims to develop a wettable formulation bioproduct from antagonistic bacteria, Bacillus stercoris isolate B.PNR1, and Streptomyces sp. isolate S.PNR29, targeting Fusarium oxysporum f.sp. lycopersici (Fol), the cause of Fusarium wilt disease in tomatoes, while also promoting plant growth. The survivability of bacterial cells in the product was assessed over a 180-day period at 4°C and 28°C. The bioproducts demonstrated significant control of Fusarium wilt disease, with B. stercoris isolate B.PNR1 bioproducts exhibiting superior disease control percentages compared to Streptomyces sp. isolate S.PNR29 bioproducts and commercial alternatives. Additionally, the bioproducts positively influenced tomato seed germination and seedling growth, with Streptomyces sp. isolate S.PNR29 bioproducts showing better growth performance in terms of plant length, weight measurements, and seed germination. In conclusion, B. stercoris isolate B.PNR1 and Streptomyces sp. isolate S.PNR29 bioproducts emerge as promising biocontrol agents, showcasing sustained efficacy against Fol and significant positive impacts on plant growth, thereby highlighting their potential for sustainable agriculture practices. [ABSTRACT FROM AUTHOR]

Background: Chickpea (Cicer arietinum L.) is the most important leguminous crop around the world. Fusarium wilt incited by Fusarium oxysporum f. sp. ciceris is a major biotic constraint in chickpea production. The present investigation was undertaken to evaluate the efficacy of plant extracts, fungicides and bio-agents against Fusarium oxysporum f. sp. ciceris under in vitro and field conditions. Methods: Plant extracts and fungicides were evaluated using poison food technique while antagonistic activity of bio-agents was studied using dual culture technique under in vitro conditions. Field trials were conducted to evaluate the efficacy of different plant extracts, fungicides and bio-agents against Fusarium wilt at Experimental Area of Plant Pathology, CCS HAU, Hisar. Result: Among thirteen plant extracts evaluated in vitro, neem leaves extract was found to be the most effective in inhibiting mycelial growth of F. oxysporum f. sp. ciceris followed by datura leaves’ and garlic cloves’ extract which were statistically at par. Out of six plant extracts tested against Fusarium wilt under field conditions, seed treatment with extracts of neem and datura leaves at 10% concentration were most effective and curtailed the wilt incidence by 39.02 and 34.14% along with 7.55 and 6.83% enhanced seed yield. Among fungicides, carbendazim 50 WP was the most toxic fungicide in restricting colony diameter of the pathogen with the least EC50 and EC90 values of 1.28 and 15.24 ppm a.i. followed by azoxystrobin 23 SC with corresponding values of 1.57 and 49.16 ppm a.i., respectively. Seed treatment with carbendazim 50 WP and azoxystrobin 23 SC were superior over other treatments and provided 88.41 and 85.98% reduction in disease incidence along with 12.85 and 10.99% higher seed yield over control. Among the bio-agents tested, T. viride and T. harzianum gave the best results in suppressing the pathogen growth in vitro and in minimizing the disease incidence coupled with improvement in seed yield under field conditions. The present study has provided chemical and non-chemical measures for integrated management of chickpea wilt [ABSTRACT FROM AUTHOR]

In the early decades of British settlement at Sydney Cove in 1788, the struggling colonials tried their hand at growing edible bananas but invariably failed. However, they grew extremely well in the Moreton Bay colony (Brisbane) and over time banana growing became an important agricultural industry there, particularly after the introduction of the Cavendish variety. All was progressing well until a new disease appeared in plantations around Brisbane in the early 1870s. The medical practitioner and naturalist Joseph Bancroft investigated the problem and concluded that a fungus was implicated as the causal agent. In the early 1900s, following serious outbreaks of a disease with similar symptoms in Caribbean countries (where it was called Panama Disease), the American bacteriologist Erwin Frink Smith studied the same disease in Cuba, and named the pathogen Fusarium cubense. Another American scientist, Elmer Walker Brandes, conclusively proved that Fusarium cubense (now called Fusarium oxysporum f.sp. cubense) was the cause of the banana disease. Bancroft's discovery of the disease now called Fusarium Wilt not only predates other reports of the disease in the Caribbean but also represents the first scientific investigation of a plant disease in Australia. Within the first forty years of English colonisation of Australia, the climate of Queensland proved to be the ideal place for the commercial production of bananas. It was in the south-eastern corner of the state that a new disease of banana (now called Fusarium Wilt) was identified by a Brisbane physician, Dr. Joseph Bancroft, in the early 1870s. The disease was given the name 'Panama disease', despite the fact that it was not discovered in Panama until twenty years later. Photograph by Andre Drenth. [ABSTRACT FROM AUTHOR]

The United States is the third largest producer of cotton and the largest exporter of cotton globally. Fusarium wilt, caused by the soilborne fungal pathogen Fusarium oxysporum f. sp. vasinfectum (Fov), was estimated to cause a $21 million cotton yield loss in 2022. Historically, Alabama was an important producer of cotton in the Southeastern United States and was the first state in which Fusarium wilt on cotton was described. To assess the genetic diversity of Fov field isolates in Alabama, 118 field isolates were collected from six counties across the state from 2014 to 2016. Phylogenetic analysis using TEF1 and RPB2 placed the Fov field isolates into 18 haplotypes. Upon profiling the Tfol transposon insertion in the NAT gene, it was determined that no race 4 isolates were recovered in Alabama. Representatives of all field isolate haplotypes caused disease on Upland cotton variety Rowden in a hydroponic test tube assay. Two haplotype A isolates were the most aggressive isolates recovered, and haplotype A isolate TF1 was more aggressive than the race 4 isolate 89-1A on Upland cotton and had similar symptom severity on Pima cotton. Karyotype profiling indicted an abundance of small chromosomes characteristic of karyotypes that include accessory chromosomes, with considerable variability between isolates. Collectively, our study indicates that Fov isolates from Alabama are genetically diverse, which may have been promoted by its persistence in cotton fields. [ABSTRACT FROM AUTHOR]

Fusarium wilt, caused by Fusarium oxysporum f. sp. passiflorae (FOP), stands out as an obstacle to the production of Passiflora edulis Sims. Little is known about the interaction of FOP with substrates and pH ranges that can be used in the development of management strategies or selection for resistance in Passiflora spp. Thus, the effect of different soil: manure or soil: coconut fiber ratios with pH ranging from acidic to alkaline on the production of FOP propagules was evaluated. The experiment was carried out in a completely randomized design, using four soil: manure or soil: coconut fiber ratios (5:0, 5:2, 5:4, 5:6 (v:v)). Each mixture's pH was adjusted from 4.2 to 8.0 (soil: manure) or 4.2 to 9.7 (soil: coconut fiber). The production of microconidia, macroconidia, chlamydospores and colony forming units was evaluated at 3, 7, 14, 21 and 28 days after substrate infestation. The greatest number of propagules was registered in the groups treated with the highest proportions of manure or coconut fiber. The use of manure, regardless of the pH range, provided increases of 98%, 48%, and 13% in the number of colony forming units, microconidia and chlamydospores, respectively, in relation to the spores produced in substrates using coconut fiber. However, the production of macroconidia was 66% higher when fiber was used. Chlamydospore production was not affected by substrate pH, unlike other propagules with greater activity at slightly acidic, neutral or alkaline pH. The use of soil plus cattle manure in the ratios 5:4 or 5:6 with a pH between 5.1 and 8.0 was associated with the highest production of FOP propagules. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the biocontrol potential of Meyerozyma guilliermondii (CECT13190), an endophytic yeast, and its role in mitigating the adverse effects of abiotic and biotic stress in cucumber plants. The relevance of this study lies in addressing the threat of Fusarium wilt, a major fungal disease that impacts cucumber crop productivity, as well as the exacerbation of food scarcity caused by climate change-induced abiotic stress factors such as high temperatures and drought. The study was conducted in a greenhouse environment where Cucumis sativus seedlings were exposed to biotic (F. oxysporum inoculation) and abiotic stress conditions (heat and water deficit). The impact of M. guilliermondii on treated plants' physiology, growth, development, and flowering was assessed. The study confirmed the biocontrol activity of M. guilliermondii against F. oxysporum and highlighted its positive effects as a plant growth promoter. It enhanced overall plant health, activated natural defense mechanisms against F. oxysporum, and alleviated the detrimental impacts of abiotic stress. Notably, M. guilliermondii also induced early flowering in cucumber plants. This research underscores the potential of M. guilliermondii as a biocontrol agent for managing Fusarium wilt, enhancing stress tolerance, promoting early flowering, and offering promising prospects for sustainable crop production amidst fungal diseases and climate change-induced stressors. The findings emphasize the importance of utilizing M. guilliermondii to improve cucumber crop productivity and address food scarcity challenges. [ABSTRACT FROM AUTHOR]

To assess the genomic diversity of Fusarium oxysporum f. sp. lini strains and compile a comprehensive gene repertoire, we constructed a pangenome using 13 isolates from four different clonal lineages, each exhibiting distinct levels of virulence. Syntenic analyses of two selected genomes revealed significant chromosomal rearrangements unique to each genome. A comprehensive examination of both core and accessory pangenome content and diversity points at an open genome state. Additionally, Gene Ontology (GO) enrichment analysis indicated that non-core pangenome genes are associated with pathogen recognition and immune signaling. Furthermore, the Folini pansecterome, encompassing secreted proteins critical for fungal pathogenicity, primarily consists of three functional classes: effector proteins, CAZYmes, and proteases. These three classes account for approximately 3.5% of the pangenome. Each functional class within the pansecterome was meticulously annotated and characterized with respect to pangenome category distribution, PFAM domain frequency, and strain virulence assessment. This analysis revealed that highly virulent isolates have specific types of PFAM domains that are exclusive to them. Upon examining the repertoire of SIX genes known for virulence in other formae speciales, it was found that all isolates had a similar gene content except for two, which lacked SIX genes entirely. [ABSTRACT FROM AUTHOR]

Fusarium oxysporum f. sp. capsici (Foc) poses a significant position in agriculture that has a negative impact on chili plant in terms of growth, fruit quality, and yield. Biological control is one of the promising strategies to control this pathogen in crops. Chili is considered as one of the most important crops in the Hyderabad region that is affected by Fusarium wilt disease. The pathogen was isolated from the infected samples in the region and was confirmed by morphological characteristics and PCR with a band of 488 bp. The bacterial strains were isolated from the rhizosphere soil of healthy plant and also confirmed by PCR with a band of 1,542 bp.The molecular characterization of the fungal and bacterial strain has shown 99.9% homology with the retrieved sequences of Fusarium oxysporum f. sp. capsici and Bacillus subtilis from NCBI. The 1-month-old Ghotki chili plants were inoculated with 1×105 cfu spore/ml−1 suspension and confirmed that the FOC-1 is responsible for chili Fusarium wilt disease. Subsequently, among the 33 screened Bacillus strains, only 11 showed antagonistic activity against F. oxysporum. Out of these, only two strains (AM13 and AM21) have shown maximum antagonistic activity against the pathogen by reducing the infection and promoting growth parameters of chili plants under both in vitro and greenhouse conditions. The study suggested that biological control is the most promising control strategy for the management of Fusarium wilt of chili in the field. [ABSTRACT FROM AUTHOR]

This study evaluates cellular damage, metabolite profiling, and defence‐related gene expression in tomato plants and soil microflora during Fusarium wilt disease after treatment with B. tequilensis PBE‐1.Histochemical analysis showed that PBE‐1 was the primary line of defence through lignin deposition and reduced cell damage. GC–MS revealed that PBE‐1 treatment ameliorated stress caused by F. oxysporum infection. PBE‐1 also improved transpiration, photosynthesis, and stomatal conductance in tomato. qRT‐PCR suggested that the defence‐related genes FLS2, SERK, NOS, WRKYT, NHO, SAUR, and MYC2, which spread infection, were highly upregulated during F. oxysporum infection, but either downregulated or expressed normally in PBE‐1 + P treated plants. This indicates that the plant not only perceives the bio‐control agent as a non‐pathogen entity but its presence in normal metabolism and gene expression within the host plant is maintained. The study further corroborated findings that application of PBE‐1 does not cause ecological disturbances in the rhizosphere.Activity of soil microflora across four treatments, measured by Average Well Colour Development (AWCD), showed continuous increases from weeks 1 to 4 post-pathogen infection, with distinct substrate usage patterns like tannic and fumaric acids impacting microbial energy source utilization and diversity. Principal Component Analysis (PCA) and diversity indices like McIntosh, Shannon, and Simpson further illustrated significant microbial community shifts over the study period.In conclusion, our findings demonstrate that B. tequilensis PBE‐1 is an ideal bio‐agent for field application during Fusarium wilt disease management in tomato. [ABSTRACT FROM AUTHOR]

Secreted in Xylem (SIX) are small effector proteins released by Fusarium oxysporum f.sp. cubense (Foc) into the plant’s xylem sap disrupting the host’s defence responses causing Fusarium wilt disease resulting in a significant decline in banana crop yields and economic losses. Notably, different races of Foc possess unique sets of SIX genes responsible for their virulence, however, these genes remain underutilized, despite their potential as biomarkers for early disease detection. Herein, we identified seven SIX genes i.e. SIX1, SIX2, SIX4, SIX6, SIX8a, SIX9a and SIX13 present in Foc Tropical Race 4 (FocTR4), while only SIX9b in Foc Race 1 (Foc1). Analysis of SIX gene expression in infected banana roots revealed differential patterns during infection providing valuable insights into host–pathogen interactions, virulence level, and early detection time points. Additionally, a comprehensive analysis of virulent Foc1_C2HIR and FocTR4_C1HIR isolates yielded informative genomic insights. Hence, these discoveries contribute to our comprehension of potential disease control targets in these plants, as well as enhancing plant diagnostics and breeding programs. [ABSTRACT FROM AUTHOR]

Bananas, a staple food globally and a key agricultural commodity, face a severe threat from the fungus Fusarium oxysporum f. sp. cubense (Foc), significantly impacting production. Genetic improvement to develop resistant cultivars stands out as a crucial strategy to mitigate this disease. This study focused on assessing and recommending enhanced diploid banana varieties for resistance against Foc subtropical race 4 (ST4) and Foc race 1 (R1). Twenty-four improved diploids developed by Embrapa, Brazil, underwent evaluation. Utilizing a scale for internal symptoms at 90 days after inoculation, genotypes were categorized from highly resistant to highly susceptible based on the internal symptom index. The diploid M53 exhibited high resistance to Foc R1 and resistance to Foc ST4, while only the diploid CNPMF 0534 demonstrated complete resistance to both R1 and ST4, with resistance to the latter likely associated with penetration, primarily due to the presence of callose. These findings provide valuable insights for banana and plantain breeding programs, offering selected diploids for crossbreeding with commercial cultivars to develop new, resistant genotypes against Foc. [ABSTRACT FROM AUTHOR]

Fusarium wilt seriously endangers banana production, it causes yield loss and even no yield. It is spread by soil and transportation of seedlings, and chlamydospores of its pathogen survive in soil for 30 years. It is very difficult for the disease to be controlled, and it is always the focus of the government, academic field and banana industry. The experts, scholars, and related practitioners of domestic and abroad have done extensive and deep related research for solving this hard issue. This paper reviewed the previous research progress from the occurrence and harm of banana Fusarium wilt, the relationship between plant rhizosphere microecology and soil-borne diseases, banana rhizosphere microecology and their effects and contributions in Fusarium wilt control. The paper proposed the research trends of the interaction mechanism between Fusarium wilt and banana rhizosphere microecology, strain screening scope and isolating incubation methods, development and application of biocontrol agents with high efficiency and strong stability, aiming to provide references for subsequent in-depth study of banana rhizosphere microecology, the excavation and innovation utilization of excellent biological control resources and the efficient control of banana Fusarium wilt. [ABSTRACT FROM AUTHOR]

Fusarium wilt of banana, caused by Fusarium oxysporum f. sp. cubense (Foc), is a serious disease that threatens banana production worldwide. It is a long-standing problem in Hawaii, but previously, there was little knowledge of the causal pathogen. We isolated a strain of Foc, named Foc-UH, from a field experiencing the disease epidemic in Hawaii. Infection assays of a diverse panel of 26 banana clones, including varieties used for differentiating pathogen races and fruit production, revealed that Foc-UH has a race 1 pathogenic phenotype with an intermediate race 2 virulence and revealed the differential resistance of varieties to infection. Separate phylogenetic analyses using the barcoding regions of three nuclear genes, seven complete nuclear genes, and single-nucleotide polymorphisms within conserved whole-genome protein coding sequences placed Foc-UH into recently proposed taxonomic frameworks relevant to Foc and the F. oxysporum species complex. Screening of the 99.7% complete draft genome identified five secreted in xylem (SIX) gene homologs: SIX1d, SIX1f, SIX9a, SIX9b, and SIX13a. This profile is similar to that of several race 1 isolates except for the absence of SIX4 and SIX6. Foc-UH was morphologically dissimilar to the nearest related isolates. Altogether, this study identified a unique isolate that causes banana Fusarium wilt, which represents the first characterization of the causal pathogen in Hawaii. The findings and genomic resources generated in this study are expected to guide banana breeding and cultivar deployment in Hawaii and beyond and contribute to further understanding of the pathogenicity and evolutionary systematics of Foc. [ABSTRACT FROM AUTHOR]

Fusarium wilt in Cymbidium ensifolium, caused by Fusarium oxysporum, is highly contagious and poses a severe hazard. It significantly reduces the ornamental value of C. ensifolium and causes substantial economic losses in agricultural production. Nucleotide-binding site–leucine-rich repeat (NBS-LRR) genes are key regulatory factors in plant disease resistance responses, playing vital roles in defending against pathogen invasions. In our study, we conducted a comprehensive analysis of the NBS-LRR gene family in the genome of Cymbidium ensifolium. Phylogenetic analysis identified a total of 31 NBS-LRR genes encoding NB-ARC proteins, which were categorized into five classes (CNL, CN, NL, N, RNL) based on their protein structural domains. These genes were found to be unevenly distributed across eight chromosomes. Physicochemical analysis revealed significant variances in molecular weight and sequence length among the family members. Subcellular localization results indicated that most genes primarily reside in the cytoplasm and cell membrane, suggesting that the primary sites of disease resistance responses may be the cell membrane and cyto-plasm. Furthermore, noticeable disparities were observed in gene structures and conserved motifs among different categories of family genes. Promoter analysis indicated that cis-regulatory elements are mainly associated with plant stress, jasmonic acid, gibberellin, and other development-related factors, suggesting that CeNBS-LRR genes mainly resist external stress through hormones such as abscisic acid and jasmonic acid. We characterized twenty-seven CeNBS-LRR gene expression patterns of healthy C. ensifolium at different periods after Fusarium wilt infection, and found that those genes exhibit a temporospatial expression pattern, and that their expression is also responsive to Fusarium wilt infection. By analyzing the expression pattern via transcriptome and qRT-PCR, we speculated that JL006442 and JL014305 may play key roles in resisting Fusarium wilt. This study lays the groundwork and holds considerable significance as a reference for identifying disease-resistant genes and facilitating genetic breeding in C. ensifolium. [ABSTRACT FROM AUTHOR]

Watermelon is commonly affected by Fusarium wilt in a monoculture cropping system. Wheat intercropping alleviates the affection of Fusarium wilt of watermelon. The objective of this study was to determine the effects of wheat and watermelon intercropping on watermelon growth and Fusarium wilt. Our results showed that wheat and watermelon intercropping promoted growth, increased chlorophyll content, and photosynthesis of watermelon. Meanwhile, wheat and watermelon intercropping inhibited watermelon Fusarium wilt occurrence, decreased spore numbers, increased root vigor, increased antioxidant enzyme activities, and decreased malondialdehyde (MDA) content in watermelon roots. Additionally, wheat and watermelon intercropping enhanced the bacterial colonies and total microbes growth in soil, decreased fungi and Fusarium oxysporum f. sp. niveum (FON) colonies, and increased soil enzyme activities in watermelon rhizosphere soil. Our results indicated that wheat and watermelon intercropping enhanced watermelon growth and decreased the incidence of Fusarium wilt in watermelon. These effects could be due to intercropping inducing physiological changes, regulating soil enzyme activities, and/or modulating soil microbial communities. [ABSTRACT FROM AUTHOR]

Common bean production is constrained by a multitude of biotic constraints including bean flies and Fusarium wilt in tropical and subtropical farming systems globally. As these pests and diseases attack the crop beneath the soil, excessive applications of synthetic pesticides are frequently used for their control. The use of plant-based pesticides could be a more sustainable management approach; however, few studies have investigated their application for controlling soil-borne pests and diseases. This study aimed to evaluate the efficacy of pesticidal plants and soil fertility management for controlling bean fly (Ophiomyia spp.) and Fusarium wilt (Fusarium spp.) using extracts and pastes of Azadirachta indica, Tephrosia vogelii, Tagetes minuta, Lippia javanica, Cymbopogon citratus and Ocimum gratissimum. To protect against Fusarium wilt and bean fly, pesticidal plants were applied as a seed coating and/or foliar spray, and demonstrated that common bean seeds coated with T. vogelii resulted in higher yields than other pesticidal plants and the synthetic pesticide control treatment. Treatments to target bean fly damage showed no significant difference between application methods on the oviposition rate of bean fly. An integrated treatment of T. minuta with 2 g Diammonium phosphate fertilizer and high compost led to higher yields than other treatments. Our results indicate that key soil-borne pests and pathogens of common bean can be effectively managed without synthetic pesticide inputs, while seed ball pastes of pesticidal plants combined with soil fertility management can increase crop yields using cost-beneficial agroecological farming systems. [ABSTRACT FROM AUTHOR]

Fusarium wilt is a fungal disease that has a significant impact on chickpeas worldwide. This study examined the response of 58 chickpea genotypes to Fusarium wilt. The experiment was conducted over two growing seasons at the Sararoud and Maragheh research stations at the Drylands Agricultural Research Institute of Iran. Genotype resistance was screened through wilt incidence records and nonparametric stability statistic evaluation. The identified resistant genotypes were then evaluated in the greenhouse for their response to four isolates of Fusarium oxysporum f. sp. ciceris (races 1/BC, 2, 4, and 6). Out of 58 genotypes, 32 exhibited moderate resistance, while 24 showed strong resistance abilities. Under warmer conditions, disease severity was higher, with scores at the Sararoud location being higher than those at the Maragheh location. Of the total genotypes across all locations and years, 41.4% were resistant, 55.17% were moderately resistant, 1.72% were susceptible, and 1.72% were highly susceptible. The nonparametric stability measures S(1), S(2), and S(3) identified FLIP 05-42C and FLIP 05-43C as stable and resistant genotypes. The study found that Azad/Hashem K3 was stable based on the non-parametric stability measure S(6). Other resistant genotypes were identified using stability parameters NP(1), NP(3), and NP(4), while FLIP 05-104C was identified by NP(2). The genotypes selected by nonparametric stability parameters showed resistance against at least two Fusarium oxysporum f. sp. ciceris races. The screening method and nonparametric stability statistics used in this study were effective in identifying sources of resistance to Fusarium oxysporum f. sp. ciceris. [ABSTRACT FROM AUTHOR]

Abstract Fusarium wilt is an important disease on chili plants caused by the fungus Fusarium oxysporum. This study aims to determine the effectiveness of secondary metabolites from 2 Pseudomonad isolates in controlling Fusarium wilt in chili plants and their effect on chili plant growth. This research was conducted in two stages, namely in vitro, which was carried out in the plant health laboratory and greenhouse, Faculty of Agriculture, Universitas Pembangunan Nasional Veteran Jawa Timur, and in vivo which was carried out in chili plantations known to be endemic to Fusarium wilt in Menganti, Gresik. The research design used in this study was Completely Randomized Design for in vitro testing and Randomized Group Design for in vivo testing by testing 9 treatments repeated 3 times. The treatment tested was control, secondary metabolite application of Pseudomonas isolates PY-122 and PY-142 with concentrations of 20% 30%, 40% and 50%. The variables observed were inhibition of secondary metabolites on the growth of Fusarium fungus, disease incubation period, disease severity index, and plant growth. Sequencing results with 16rRNA gene markers for both Pseudomonas isolates showed similarities to Pseudomonas sp. The results showed that the treatment of secondary metabolite PY-142 with a concentration of 50% showed the highest consistent inhibition. In the greenhouse and field tests, the two isolates slowed down the disease incubation period and development compared to controls. In agronomical observations, the average plant height, number of leaves, root length, and appearance of the first flower on the treated plants were higher and more numerous than the control plants.

The aim of this study was to evaluate the effects of Bacillus velezensis Bv-116 and its bio-organic fertilizer on the control of cucumber Fusarium wilt caused by Fusarium oxysporum f. sp. Cucumerinum (FOC), the promotion of growth of cucumber seedlings, and the soil microbial community. B. velezensis Bv-116 exhibited an inhibition rate of 84.93% against FOC, as well as broad-spectrum inhibitory activities against other soil-borne plant pathogenic fungi. Fermentation products of B. velezensis Bv-116 destroyed the cell structure of FOC and inhibited the growth of FOC mycelium. These products were identified as volatile antimicrobial gases, proteases and cellulases. In the greenhouse pot experiment, both B. velezensis Bv-116 and its bio-organic fertilizer exhibited significant promoting effects on cucumber growth, and a significant reduction in the incidence and disease severity index of cucumber wilt (p < 0.05). Analysis of the microbial community structure of cucumber rhizosphere soil revealed that inoculation of B. velezensis Bv-116 and its bio-organic fertilizer increased the abundance of genera with biocontrol capabilities against plant pathogens. In addition, inoculation of the bio-organic fertilizer reversed the excessive proliferation of Fusarium and Acidobacteria. Our results suggest the potential of inoculating B. velezensis Bv-116 and its bio-organic fertilizer as an environmentally friendly biocontrol strategy against cucumber wilt.

IntroductionFusarium wilt, caused by Fusarium oxysporum f. sp. cubense (Foc), poses a significant global threat to banana cultivation. Conventional methods of disease management are increasingly challenged, thus making it necessary to explore alternative strategies. Bacterial endophytes, particularly from resistant genotypes, are gaining attention as potential biocontrol agents. Sphingobacterium thalpophilum, isolated from the resistant banana cultivar Pisang lilin (JALHSB010000001-JALHSB010000029), presents an intriguing prospect for combating Fusarium wilt. However, its underlying biocontrol mechanisms remain poorly understood. This study aimed to elucidate the antifungal efficacy of S. thalpophilum NMS02 S296 against Foc and explore its biocontrol mechanisms at the genomic level.MethodsWhole genome sequencing of S. thalpophilum NMS02 S296 was conducted using next-generation sequencing technologies and bioinformatics analyses were performed to identify genes associated with antifungal properties. In vitro assays were used to assess the inhibitory effects of the bacterial isolate on the mycelial growth of Foc. To explore the biomolecules responsible for the observed antagonistic activity, metabolites diffused into the agar at the zone of inhibition between Foc S16 and S. thalpophilum NMS02 S296 were extracted and identified.ResultsWhole genome sequencing revealed an array of genes encoding antifungal enzymes and secondary metabolites in S. thalpophilum NMS02 S296. In vitro experiments demonstrated significant inhibition of Foc mycelial growth by the bacterial endophyte. Comparative genomic analysis highlighted unique genomic features in S. thalpophilum linked to its biocontrol potential, setting it apart from other bacterial species.DiscussionThe study underscores the remarkable antifungal efficacy of S. thalpophilum NMS02 S296 against Fusarium wilt. The genetic basis for its biocontrol potential was elucidated through whole genome sequencing, shedding light on the mechanisms behind its antifungal activity. This study advanced our understanding of bacterial endophytes as biocontrol agents and offers a promising avenue for plant growth promotion towards sustainable strategies to mitigate Fusarium wilt in banana cultivation.

Fusarium wilt of Banana (FWB) caused by Fusarium oxysporum f. sp. cubense (Foc) poses a significant threat to the banana industry, with current inadequate control measures. This study evaluated the antifungal potential of nine Streptomyces strains isolated from Antarctic soil samples, using Casein-Starch media to stimulate the production of antifungal compounds. The inhibition spectrum against Foc was assessed under laboratory conditions using the well diffusion on Mueller-Hinton agar, with antifungal activity measured in arbitrary units (AU/mL) and minimum inhibitory concentration (MIC) tested using ethyl acetate extracts. Among the nine isolates, K6 and E7 were closely related to Streptomyces polyrhachis and Streptomyces fildesensis, exhibited significant antifungal activity, with K6 and E7 showing 320 and 80 AU/mL, and MIC values of 250 and >500 ppm, respectively. These findings highlight K6 and E7 as potential biocontrol agents against Foc, offering new avenues for sustainable Fusarium wilt management in banana cultivation.

Fusarium wilt of banana (Musa spp.) primarily caused by a soil-borne fungus Fusarium oxysporum f. sp. cubense (Foc), presents a significant threat to the banana industry worldwide. To propagate bananas efficiently, tissue culture techniques are commonly employed, to yield quality planting material with desirable traits and devoid of harmful microorganisms. However, the tissue cultured plantlets may be more susceptible to Fusarium wilt than traditional planting material due to the lack of indigenous beneficial endophytes. Endophytes are microorganisms that colonize internal tissues without causing pathogenicity and have been found to occur in all plant species. They form symbiotic relationships with host plants, enhancing their performance. Endophytes also promote plant growth due to the production of secondary metabolites like auxin and gibberellins. Additionally, some compounds act as antibiotic and antifungal thus inhibiting pathogen invasion and its growth. Since the applied endomicrobiome occupies the niche areas of Foc pathogen in the banana corm, thus these microbes not only avoid the entry of Foc but also promote the plant’s growth and development due to the production of secondary metabolites. This is a promising biological solution for sustainable banana cultivation in the era of “climate change and chemical free farming”.