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Background: Root rot, wilt diseases, and rooting processes have been the major factors that constrain schefflera production. This study focuses on the impact of innovative applications of eco-friendly materials like chitosan nanoparticles loaded with l-proline or indole butyric acid to replace traditional chemical fungicides in controlling root rot and wilt diseases, as well as the vegetative propagation success of leafy stem schefflera cuttings. Results: Fusarium foeten (strain 1) and Fusarium falciforme (strains 2 and 4) were first identified as root rot and wilt pathogens of schefflera in Egypt based on morphological features and confirmed with molecular analyses. Fusarium foetens (strain 1) and F. falciforme (strain 2) have the most aggressive action, as the infection percentages significantly increased in the pathogenicity test. The disease incidence reached 38.88 and 44.44%, respectively, whereas the disease severity was 18.51 and 26.84%, respectively. Chitosan nanoparticles at a concentration of 25 mg/L were the most effective dose, leading to a significant reduction in disease incidence to 25.00%, disease severity to 4.17%, and playing a vital role in activating plant defense, which correlates well with improved growth characteristics. The novel strategy of L-proline loaded on chitosan nanoparticles (LP-CSNPs) application occupied the first rank at protective influence against root rot and wilt disease-induced oxidative stress, signaling a defensive function that was freelance verified. L-proline loaded on chitosan nanoparticles (LP-CSNPs) at 0.125–0.25 g/L had a significant impact on reducing the incidence and severity of root rot and wilt diseases, as well as improving photosynthetic pigments and free radical scavenging activities, which included strengthening plant defense and further validating the findings from the biochemical trait analysis. The TT biplot graph was an influential statistical tool to study the impacts of treatments on schefflera production and its attributes and to discover the interrelationships among them. Conclusions: Applying LP-CSNPs is one of the best techniques to manage schefflera root rot and wilt diseases, since it can be utilized as a growth stimulator and defense activator with sustainable increased efficiency. [ABSTRACT FROM AUTHOR]

African eggplant (AEP) (Solanum aethiopicum group Gilo) is an important vegetable with considerable economic value in Ghana and tropical Africa. However, fungal diseases threaten its cultivation. Surveys conducted in 2021 and 2022 growing seasons across 35 commercial farms in five regions of Ghana revealed symptoms of crown rot and wilt affecting AEP. This study was undertaken to identify and characterise 36 fungal isolates causing these diseases in AEPs using morphological, molecular and pathogenicity assays. Morphological and molecular analyses of the Btub2, Tef‐1α and Rpb2 sequences identified two Fusarium species (F. elaeidis and F. fredkrugeri) and three Neocosmospora species (N. falciforme, N. suttoniana and N. solani) associated with the plant diseases. F. elaeidis (14 isolates) and N. falciforme (14) were the most commonly isolated species from symptomatic plants. Specifically, F. elaeidis was found in wilting plants, while F. fredkrugeri and the three Neocosmospora spp. were more associated with wilting plants with crown rot symptoms than plants with only wilt symptoms. All identified species exhibited pathogenicity when inoculated onto AEP roots and stems, confirming field observations. F. elaeidis was the most aggressive in inducing wilt symptoms, while N. solani and N. suttoniana were particularly aggressive in inducing crown rot symptoms. This study is the first to document that F. elaeidis, F. fredkrugeri, N. falciforme and N. suttoniana are pathogens causing wilt and crown rot in AEP in Ghana. These findings provide essential insights for developing effective disease management strategies to reduce losses from these fungal species. [ABSTRACT FROM AUTHOR]

Abstract Background Root rot, wilt diseases, and rooting processes have been the major factors that constrain schefflera production. This study focuses on the impact of innovative applications of eco-friendly materials like chitosan nanoparticles loaded with l-proline or indole butyric acid to replace traditional chemical fungicides in controlling root rot and wilt diseases, as well as the vegetative propagation success of leafy stem schefflera cuttings. Results Fusarium foeten (strain 1) and Fusarium falciforme (strains 2 and 4) were first identified as root rot and wilt pathogens of schefflera in Egypt based on morphological features and confirmed with molecular analyses. Fusarium foetens (strain 1) and F. falciforme (strain 2) have the most aggressive action, as the infection percentages significantly increased in the pathogenicity test. The disease incidence reached 38.88 and 44.44%, respectively, whereas the disease severity was 18.51 and 26.84%, respectively. Chitosan nanoparticles at a concentration of 25 mg/L were the most effective dose, leading to a significant reduction in disease incidence to 25.00%, disease severity to 4.17%, and playing a vital role in activating plant defense, which correlates well with improved growth characteristics. The novel strategy of L-proline loaded on chitosan nanoparticles (LP-CSNPs) application occupied the first rank at protective influence against root rot and wilt disease-induced oxidative stress, signaling a defensive function that was freelance verified. L-proline loaded on chitosan nanoparticles (LP-CSNPs) at 0.125–0.25 g/L had a significant impact on reducing the incidence and severity of root rot and wilt diseases, as well as improving photosynthetic pigments and free radical scavenging activities, which included strengthening plant defense and further validating the findings from the biochemical trait analysis. The TT biplot graph was an influential statistical tool to study the impacts of treatments on schefflera production and its attributes and to discover the interrelationships among them. Conclusions Applying LP-CSNPs is one of the best techniques to manage schefflera root rot and wilt diseases, since it can be utilized as a growth stimulator and defense activator with sustainable increased efficiency. Graphical Abstract

The search for active inducers against diseases in the formula of therapeutic nutrients has become a necessity for many researchers. The study's chief purpose was to make agronomic farming simpler by applying newly created therapeutic nutrients. The novelty of this research is the applied of algal extracts in adding to minerals as therapeutic nutrion. Calcium (Maxifos Ca), Ascophyllum nodosum (Greencal), and Arthrospira platensis (A. platensis), were tested for induction pepper plant resistance against Fusarium wilt. The disease index (DI), morphological growth, photosynthetic pigments, free proline, total phenol, hydrogen peroxide (H2O2), malondialdehyde (MDA), and antioxidant enzymes as reactions to the induction of protection in challenged tested plants were measured. Results revealed that the use of entirely different treatments significantly minimized the danger of Fusarium wilt. Treatment of infected plants with Maxifos Ca was the best treatment, as it reduced the DI to 25% and thus reduced symptoms and improved the percentage of plant protection from the disease by 69.6%. Surprisingly, it was widely assumed that Greencal was the greatest treatment for restoring vegetative growth, followed by Maxifos Ca and an algal extract, A. platensis. The application of Greencal, followed by Maxifos Ca, and then A. platensis significantly increased the expression of all metabolic resistance indices (phenols, polyphenol oxidase, and peroxidase). The best treatments for reducing the signs of stress represented in (MDA and H2O2) were Maxifos Ca and then Greencal. According to the findings the use of Maxifos Ca, Greencal, and A. platensis as alternate therapeutic nutrients of eco-destructive chemically synthesized fungicides appears to be a significant methodology for reducing the harmful effects of Fusarium wilt on pepper plants. [ABSTRACT FROM AUTHOR]

Wilt disease affects alfalfa plants (Medicago sativa) by disrupting their vascular tissues which limits water and nutrient uptakes leading to yield reduction. Field surveys conducted in 2017 in the oases of Southern Tunisia showed serious wilting symptoms in alfalfa, associated with leaves yellowing and root rotting. This study aims to identify the causal agents of alfalfa wilting disease, along with their cultural biodiversity and ecology of infestation. Wilted plants from six oases were sampled which led to the isolation of 79 fungal strains from roots, collars, and stems. The inoculation of the fungal strains on Medicago sativa (cv. El-Hamma) and Medicago truncatula (accessions A17 and F83005.5) induced different reactions in plants depending on the inoculated Medicago species and accession. The majority of the strains did not affect plant growth (59–86%), the second group enhanced plant growth (6–16%), and the third group induced disease symptoms associated with a reduction in seedling growth (8–24%). The molecular identification showed that 73.42% of the fungal strains belong to the genus Fusarium, including the species complexes of F. oxysporum, F. solani, F. fujikuroi, F. incarnatum-equiseti and, F. chlamydosporum; 10.13% to Alternaria; 5.06% to Rhizoctonia; and 1.27% to Aaosphaeria. The pathogenicity tests on date palm seedlings (cv. Deglet Nour) showed that strains affiliated with the genera Rhizoctonia sp. and Fusarium fujikuroi species complex reduced the growth of plants, suggesting that alfalfa constitutes an alternate host for these pathogens. Alfalfa wilting disease in Southern Tunisian oases is caused by a complex of pathogens rather than a single agent, as it is caused by a consortium of mutually interacting Fusarium species complexes (F. oxysporum, F. solani, F. fujikuroi and, F. incarnatum-equiseti), Rhizoctonia, and Alternaria, some of which act as pathogenic virulent agents and others as secondary pathogens. [ABSTRACT FROM AUTHOR]

Plant microbiota composition changes with the environment and host state, suggesting potential for engineering. However, engineering plant microbiomes is promising but currently undeveloped. This study investigated the role of root-associated bacterial microbiomes in poly-γ-glutamic acid (γ-PGA)-induced plant disease resistance. γ-PGA treatment significantly reduced wilt disease caused by Fusarium oxysporum f. sp. chrysanthemi (Foc). Quantitative PCR analysis revealed a 73.2% reduction in Foc abundance in the roots following γ-PGA exposure. However, the disease suppression effect of γ-PGA was notably weakened in sterilized soils or soils treated with bactericide, indicating the essential role of root-associated microbiomes in this process. 16S rRNA gene amplicon sequencing showed that γ-PGA treatments increased the abundance of Proteobacteria, particularly the family Burkholderiaceae, in the roots. Metabolite analysis further indicated that γ-PGA treatment significantly elevated salicylic acid (SA) levels, suggesting that SA played a critical role in the assembly of the root microbiome under γ-PGA treatment. Further experiments confirmed the antagonistic activity and induced systemic resistance (ISR) of Burkholderia sp. against Fusarium wilt. Burkholderia sp. CM72 was found to enhance plant disease resistance through antibiosis and activation of jasmonic acid (JA)-related pathways. In summary, γ-PGA significantly improved plant disease resistance by modulating the SA pathway and promoted the colonization of beneficial microbiota, particularly with Burkholderia sp. [ABSTRACT FROM AUTHOR]

Vascular wilt disease, caused by the soil-borne fungus Fusarium oxysporum (Fo), poses a threat to many crop species. Four different tomato resistance (R) genes (I-1, I-2, I-3, and I-7) have been identified to confer protection against Fo f.sp. lycopersici (Fol). These I genes are root-expressed and mount an immune response upon perception of the invading fungus. Despite immune activation, Fol is still able to colonize the xylem vessels of resistant tomato lines. Yet, the fungus remains localized in the vessels and does not colonize adjacent tissues or cause disease. The molecular mechanism constraining Fol in the vascular system of the stem remains unclear. We here demonstrate that an I-2-resistant rootstock protects a susceptible scion from Fusarium wilt, notwithstanding fungal colonization of the susceptible scion. Proteomic analyses revealed the presence of fungal effectors in the xylem sap of infected plants, showing that the lack of fungal pathogenicity is not due to its inability to express its virulence genes. To identify mobile root-derived proteins, potentially involved in controlling fungal proliferation, comparative xylem sap proteomics was performed. We identified distinct pathogenesis-related (PR) protein profiles in xylem sap from Fol-inoculated I-1, I-2, I-3, and I-7 resistant lines. Despite structural diversity, all four immune receptors trigger the accumulation of a common set of four PR proteins: PR-5x, PR-P2, and two glucan endo-1,3-β-Dglucosidases. This research provides insights into Fusarium resistance mechanisms and identifies a core set of proteins whose abundance correlates with defense against Fusarium wilt. [ABSTRACT FROM AUTHOR]

LBD transcription factors are a class of transcription factors that regulate the formation of lateral organs, establish boundaries, and control secondary metabolism in plants. In this study, we identified 37 melon LBD transcription factors using bioinformatics methods and analyzed their basic information, chromosomal location, collinearity, evolutionary tree, gene structure, and expression patterns. The results showed that the genes were unevenly distributed across the 13 chromosomes of melon plants, with tandem repeats appearing on chromosomes 11 and 12. These 37 transcription factors can be divided into two major categories, Class I and Class II, and seven subfamilies: Ia, Ib, Ic, Id, Ie, IIa, and IIb. Of the 37 included transcription factors, 25 genes each contained between one to three introns, while the other 12 genes did not contain introns. Through cis-acting element analysis, we identified response elements such as salicylic acid, MeJA, abscisic acid, and auxin, gibberellic acid, as well as light response, stress response, and MYB-specific binding sites. Expression pattern analysis showed that genes in the IIb subfamilies play important roles in the growth and development of various organs in melon plants. Expression analysis found that the majority of melon LBD genes were significantly upregulated after infection with wilt disease, with the strongest response observed in the stem. [ABSTRACT FROM AUTHOR]

Plastic mulching is a widely used intensive planting system for cotton production in China. For the present study, the effects of three plastic mulching treatments (i.e., NDNM: normal sowing date with no plastic mulching as a positive control, NDM: normal sowing date with plastic mulching, and LDM: sowing 7 days late with plastic mulching) were studied in the field on seedling disease, Verticillium wilt, and Fusarium wilt as well as on the lint yield in cotton from 2019 to 2020. The treatment effects were evaluated based on the disease incidence (DI) and disease severity index (DSI), seedling fresh weights, lint yields, and yield components. For all cultivars (SCRC28, SCRC21, and Jimian11), both the DIs and DSIs of the seedling disease were lower in the LDM treatment than in the NDNM and NDM treatments. The DIs and DSIs of Fusarium wilt for all the cultivars were higher in the NDNM treatment than in the NDM and LDM treatments. However, the DIs and DSIs for Verticillium wilt were lower in the NDNM treatment. Moreover, the seedling fresh weights, average lint yields, and boll numbers per square meter were all highest in the NDM treatment and lowest in the NDNM treatment. The results of this study demonstrated that the use of plastic mulching with a suitable seed sowing date would be an appropriate cultural practice for enhancing cotton production and reducing the severity of cotton seedling and Fusarium wilt disease. [ABSTRACT FROM AUTHOR]

An innovative tissue culture mediated incorporation of metabolite-based biomolecule (Bio-immune) at in vitro stage itself in banana cv. Grand Naine was developed and validated for the production of Fusarium oxysporum f.sp. cubense TR4 tolerant plantlets. The novel bio-immune formulation developed by us, exhibited a significant antifungal potency against Foc TR4 with a high percent inhibition (100%) at a 2.5% concentration of bio-immune on the 5th, 7th, and 9th DAI. Bio-immune integrated during in vitro shoot proliferation stage in banana cv. Grand Naine recorded significant enhancement in the growth of roots and shoots. Bio-immune (0.5%) fortified media produced 12.67 shoots per clump whereas control registered only 9.67 shoots per clump. Similarly, maximum root numbers (7.67) were observed in bio-immune plants which were significantly higher over control (5.0). The bio-immunized banana transplants recorded a higher survival rate (97.57%) during acclimatization as compared to the control (94.53%). Furthermore, evaluation of the bio-immunized plants in pot experiments revealed that unimmunized plants treated with FocTR4 (TF) exhibited mortality between 60 and 90  days. On the 90th day after planting, a high mean disease severity index (DSI) of 3.45 was observed with unimmunized plantlets while the bio-immunized plants (TFBI) and ICAR-FUSICONT treated plants (TFTR) showed substantially reduced DSI (0.20 and 1.00) compared to FocTR4 treated control (TF). Significant increases in polyphenol oxidase (PPO), peroxidase (POD), β-1,3-glucanase, phenylalanine ammonia-lyase (PAL), chitinase activities, and enhanced phenol contents were recorded in bio-immunized plants compared to unimmunized plants. Field experiments at two different locations in Bihar, India revealed that bunch weight, no. of hands/bunch, and no. of fingers/hand of bioimmune treated plants were significantly higher compared to the control. [ABSTRACT FROM AUTHOR]

Vascular wilt disease, caused by the soil-borne fungus Fusarium oxysporum (Fo), poses a threat to many crop species. Four different tomato resistance (R) genes (I-1, I-2, I-3, and I-7) have been identified to confer protection against Fo f.sp. lycopersici (Fol). These I genes are root-expressed and mount an immune response upon perception of the invading fungus. Despite immune activation, Fol is still able to colonize the xylem vessels of resistant tomato lines. Yet, the fungus remains localized in the vessels and does not colonize adjacent tissues or cause disease. The molecular mechanism constraining Fol in the vascular system of the stem remains unclear. We here demonstrate that an I-2-resistant rootstock protects a susceptible scion from Fusarium wilt, notwithstanding fungal colonization of the susceptible scion. Proteomic analyses revealed the presence of fungal effectors in the xylem sap of infected plants, showing that the lack of fungal pathogenicity is not due to its inability to express its virulence genes. To identify mobile root-derived proteins, potentially involved in controlling fungal proliferation, comparative xylem sap proteomics was performed. We identified distinct pathogenesis-related (PR) protein profiles in xylem sap from Fol-inoculated I-1, I-2, I-3, and I-7 resistant lines. Despite structural diversity, all four immune receptors trigger the accumulation of a common set of four PR proteins: PR-5x, PR-P2, and two glucan endo-1,3-β-D-glucosidases. This research provides insights into Fusarium resistance mechanisms and identifies a core set of proteins whose abundance correlates with defense against Fusarium wilt.

BACKGROUND AND OBJECTIVES: In Thailand, bacterial wilt is one of the most severe diseases that affects pathumma, also known as Curcuma alismatifolia Gagnep. Biological control was proposed to control this disease with antagonistic bacteria. The current study was conducted to screen for antagonistic microorganisms capable of inhibiting the pathogenic bacteria and to evaluate the beneficial effect of antagonistic bacteria on pathumma in vivo.METHODS: Antagonistic bacteria were isolated from soil samples obtained from several locations in Thailand and screened for antibacterial activity. Next, the optimal conditions for the growth of antagonistic bacteria were determined. The production of anibacterial substances were then characterized. The potential of antagonistic bacteria to reduce the growth of plant pathogens was evaluated under greenhouse conditions. FINDINGS: In total, 102 bacterial isolates were isolated using tryptic soy medium. After evaluating their capacity to inhibit the growth of the wilt-causing bacteria using the paper disc diffusion assay, it was found that three bacterial isolates, Bacillus subtilis SP15, Pseudomonas mosselii SP38, and Pseudomonas mosselii SP46 showed high ability to inhibit growth of the wilt-causing bacteria Enterobacter asburiae JK1, JK2, JK3, JK4, E. dissolvens JK5 and E. hormachei JK6. The optimal conditions for all antagonistic bacterial isolates were 25 or 30 degrees Celcius, at potential of hydrogen 7-8 in modified tryptic soy medium containing 0.5 percent (weight /volume) glucose or sucrose and 1.5 or 2 percent (weight/volume) peptone. The antagonists were able to produce siderophores and phenazines. Under greenhouse experiments, the mixed cultures of antagonistic bacterial isolates could reduce the wilt disease incidence, and the number of pathogenic bacteria declined compared with the diseased control plants. In addition, it was discovered that soil materials provided the best carrier materials for the successful formulation of the mixed culture of antagonistic bacteria.CONCLUSION: This study revealed that the selected antagonists were beneficial for controlling wilt disease in pathumma. This is the first scientific study on the control of wilt-disease causing Enterobacter spp. in C. alismatifolia Gagnep. in Thailand using antagonistic bacteria. It is expected that these antagonistic bacteria be useful in wilt disease management in the field for friendly and sustainable agriculture

Plant microbiota composition changes with the environment and host state, suggesting potential for engineering. However, engineering plant microbiomes is promising but currently undeveloped. This study investigated the role of root-associated bacterial microbiomes in poly-γ-glutamic acid (γ-PGA)-induced plant disease resistance. γ-PGA treatment significantly reduced wilt disease caused by Fusarium oxysporum f. sp. chrysanthemi (Foc). Quantitative PCR analysis revealed a 73.2% reduction in Foc abundance in the roots following γ-PGA exposure. However, the disease suppression effect of γ-PGA was notably weakened in sterilized soils or soils treated with bactericide, indicating the essential role of root-associated microbiomes in this process. 16S rRNA gene amplicon sequencing showed that γ-PGA treatments increased the abundance of Proteobacteria, particularly the family Burkholderiaceae, in the roots. Metabolite analysis further indicated that γ-PGA treatment significantly elevated salicylic acid (SA) levels, suggesting that SA played a critical role in the assembly of the root microbiome under γ-PGA treatment. Further experiments confirmed the antagonistic activity and induced systemic resistance (ISR) of Burkholderia sp. against Fusarium wilt. Burkholderia sp. CM72 was found to enhance plant disease resistance through antibiosis and activation of jasmonic acid (JA)-related pathways. In summary, γ-PGA significantly improved plant disease resistance by modulating the SA pathway and promoted the colonization of beneficial microbiota, particularly with Burkholderia sp.

Abstract Background Bacterial wilt caused by Ralstonia solanacearum is a devastating disease of brinjal in Bangladesh. The study was targeted to evaluate the bacterial wilt management ability of microbial consortia composed of isolated and identified native Bacillus cereus, Trichoderma harzianum and Calotropis gigantea for the first time in Bangladesh. Results Twenty bacterial strains were isolated from the rhizosphere of the brinjal plant following serial dilution method. Among the strains, HSTUB 17 showed maximum zone of inhibition (1.5 ± 0.1 cm) against R. solanacearum in the dual culture method. Molecular characterization using 16 s rRNA partial coding sequence revealed HSTUB 17 as B. cereus. Consortia composed with the identified B. cereus HSTUB 17 (108 CFU ml−1 @ 5 ml/plant), previously isolated T. harzianum (@5 mm size of four mycelial disk/plant) and aqueous leaf extracts of C. gigantea (1:1, w/v basis @ 40 ml/plant) were applied in the root zone following soil drenching method and found to reduce bacterial wilt incidence by 74.87, 66.67 and 66.67% at 30, 50 and 70 days after transplanting, respectively, in comparison with plants received only R. solanacearum (108 CFU ml−1 @ 5 ml/plant). The single application of B. cereus HSTUB 17, T. harzianum and C. gigantea also minimized wilt incidence by 21.16–37.34, 33.33 and 21.48–28.14%, respectively, on all the days of observations. The consortia of B. cereus HSTUB 17, T. harzianum and C. gigantea also resulted in maximum plant height (56.67 cm), the number of branches/plants (10.33), the number of fruits/plants (8.33) and fruit yield (25.56 ton/ha) in comparison with the plant exposed to R. solanacearum only. Conclusion The findings of the study revealed the potentiality of consortia composed of B. cereus HSTUB 17, T. harzianum and C. gigantea for the eco-friendly management of bacterial wilt of brinjal for the first time in Bangladesh.

Ailanthus altissima is among the most invasive woody species worldwide, outcompeting native trees. The fungus Verticillium nonalfalfae (VN) is promising for A. altissima biocontrol, and its effects on the host have been studied via visual assessment in a range of host species. However, little research was performed to address fungal effects on the physiological processes of non-target woody plants. We investigated the occurrence of visual and non-visually recognisable perturbations of VN infection on potted vines to evaluate the potential risks of the biocontrol pathogen on viticulture. Eighteen four-years-old Vitis vinifera (cultivar Grüner Veltliner grafted on Kober 5BB) potted plants were inoculated with VN conidial suspension of the fungus (F), while nine plants were treated with sterile water (C, control). Disease symptoms and physiological parameters were monitored throughout the experiment (seven evaluation dates), while leaf water potential, leaf mass per area (LMA) and biomass were measured at the end of the study when plant tissue was sampled for re-isolation of the fungus. In our trial, inoculations with VN induced characteristic wilting symptoms only in Ailanthus (used as side control of the inoculum), while vines remained asymptomatic, thus indicating a high degree of host specificity of VN. Limited or no impact was detected on the physiology of the non-target V. vinifera. Furthermore, the LMA and biomass measured in the two experimental groups were not different. Although fungal colonisation induced vascular discolouration in both species, the fungus could only be re-isolated from dying Ailanthus but not from vine tissue. Results suggest that V. vinifera cv Grüner Veltliner is resistant to the applied VN isolate. However, the susceptibility and physiology of additional grapevine cultivars, as well as other native woody species to VN, should be studied before promoting large-scale use of the biocontrol agent.

During season of 2020, cowpea (Vigna unguiculata) plants exhibiting sever wilt symptoms were collected from several fields in Kerbala Province of Iraq. A fungus was consistently isolated from the symptomatic tissues and identified as Fusarium solani, based on its cultural and morphological features, as well as the sequence analysis of the internal transcribed spacer (ITS), translation elongation factor-1 alpha (TEF-1a) and actin (actA). The pathogenicity of this fungus was verified on cowpea plants that reproduced the typical wilt symptoms. The fungal pathogen was re-isolated from these diseased plants and reidentified. To best of our knowledge, this is the first record of F. solani causing cowpea wilt in Kerbala, Iraq. [ABSTRACT FROM AUTHOR]

Solanum aethiopicum L. cultivation is highly constrained by wilt disease induced by Fusarium oxysporum f.sp melongenae and Meloidogyne incognita. The effects of initial population densities of these pathogens on the crop were investigated to enhance knowledge of the host-parasite interactions. The 4 x 4 factorial set of treatments were laid out in the field using the randomized complete block design with three replications. Data were collected on plant vigour, vascular discoloration, fruit weight, shoot weight, root-gall index, final nematode population, disease incidence, and disease severity. The different initial population densities of Fusarium and/or Meloidogyne spp. had detrimental effects on the crop compared to the Control. The main effects of the pathogens on the crop/wilt showed the existence of cross-over interactions for all the disease parameters. The effects of the pathogens on yield (fruit weight and shoot weight) were partially directly proportional to population densities even though the effects were significantly different (P≤0.05) compared to the Control. All the disease parameters were positively correlated. Each of the pathogens was capable of causing severe damage to the crop in either single or concomitant infection. [ABSTRACT FROM AUTHOR]

Abstract In the present era, nanomaterials are emerging as a powerful tool for management of plant disease and improving crop production to meet the growing global need for food. Thus, this paper was conducted to explore the effectiveness of five different types of nanoparticles (NPs) viz., Co3O4NPs, CuONPs, Fe3O4NPs, NiONPs, and ZnONPs as treatments for Fusarium wilt as well as their role in promoting growth of the common bean plant. The five types of NPs were applied as a treatment for wilt in two ways, therapeutic and protective plans under greenhouse conditions. In vivo experiments showed that all types of NPs significantly increased disease control and diminished the symptoms of Fusarium wilt for both incidence and severity. The recorded values for disease control using the respective NPs during the protective plan were 82.77, 60.17, 49.67, 38.23, and 70.59%. Meanwhile these values were 92.84, 64.67, 51.33, 45.61, 73.84% during the therapeutic plan. Moreover, CuONPs during the protective plan were the best among the five types of NPs employed in terms of wilt disease management. Regarding the use of these NPs as growth promoters, the obtained results confirmed the effectiveness of the five types of NPs in enhancing vegetative growth of the plant under greenhouse conditions, in comparison with control. Among the five NPs, CuONPs improved the plant vegetative growth and particularly increased the content of the photosynthetic pigments; chlorophyll-a (2.96 mg/g), -b (1.93 mg/g), and total carotenoids (1.16 mg/g). These findings suggest the successful and potential exploitation of nanomaterials in agriculture deployed as nano-based products including nano-fungicides and nano-fertilizers. In terms of sustainability, this promising and exceptional multifunctional role of these nanomaterials will surely exert positive impacts on both the environment and sustainable agriculture.

Plastic mulching is a widely used intensive planting system for cotton production in China. For the present study, the effects of three plastic mulching treatments (i.e., NDNM: normal sowing date with no plastic mulching as a positive control, NDM: normal sowing date with plastic mulching, and LDM: sowing 7 days late with plastic mulching) were studied in the field on seedling disease, Verticillium wilt, and Fusarium wilt as well as on the lint yield in cotton from 2019 to 2020. The treatment effects were evaluated based on the disease incidence (DI) and disease severity index (DSI), seedling fresh weights, lint yields, and yield components. For all cultivars (SCRC28, SCRC21, and Jimian11), both the DIs and DSIs of the seedling disease were lower in the LDM treatment than in the NDNM and NDM treatments. The DIs and DSIs of Fusarium wilt for all the cultivars were higher in the NDNM treatment than in the NDM and LDM treatments. However, the DIs and DSIs for Verticillium wilt were lower in the NDNM treatment. Moreover, the seedling fresh weights, average lint yields, and boll numbers per square meter were all highest in the NDM treatment and lowest in the NDNM treatment. The results of this study demonstrated that the use of plastic mulching with a suitable seed sowing date would be an appropriate cultural practice for enhancing cotton production and reducing the severity of cotton seedling and Fusarium wilt disease.

Essential oil nanoemulsions have received much attention in the last period for controlling of fungal plant pathogens. In this study, thyme oil nanoemulsion (TONE) was successfully prepared from thyme oil which extracted from Thymus vulgaris (T. vulgaris). The prepared TONE was characterized using DLS, Zeta potential, and TEM analyses. Results revealed that, TONE has spherical shape with size 32.7 nm. Moreover, results illustrated that TONE exhibited promising antifungal activity against Fusarium oxysporum (F. oxysporum) with minimum fungicidal concentration (MFC) 5 mg/ml. Additionally, TONE concentrations 1, 2, 3 and 4 mg/ml reduced the growth of F. oxysporum with percentages 7.78, 31.1, 52.2 and 67.8 % respectively. Disease index (DI) of Fusarium wilt reached the maximum rate by (85 %) in the Foeniculum vulgare (F. vulgare) plant infected with F. oxysporum. Application of TONE treatment on infected plants led to a decrease in DI to (17.5%) and an increase in the percentage of protection to (79.4%). Furthermore, DI was decrease to 42.5% with protection percentage 50% in the case of infected plant with TOE. Moreover, TOE, TONE played an important role in improving plant immunity by increasing phenol, proline, and antioxidant enzymes (POD&PPO) activities, as well as reducing oxidative stress by reducing (MDA & H2O2). Results revealed that TONE led to significant increase in free proline in compared to TOE. We can conclude that TOE, TONE are considered eco-friendly safe strong inducers of F. vulgare plant immunity alternatives to difenoconazole against fusarial wilt disease to preserve plant, soil, and human health.

Background: Bacterial wilt caused by Ralstonia solanacearum is a devastating disease of brinjal in Bangladesh. The study was targeted to evaluate the bacterial wilt management ability of microbial consortia composed of isolated and identified native Bacillus cereus, Trichoderma harzianum and Calotropis gigantea for the first time in Bangladesh. Results: Twenty bacterial strains were isolated from the rhizosphere of the brinjal plant following serial dilution method. Among the strains, HSTUB 17 showed maximum zone of inhibition (1.5 ± 0.1 cm) against R. solanacearum in the dual culture method. Molecular characterization using 16 s rRNA partial coding sequence revealed HSTUB 17 as B. cereus. Consortia composed with the identified B. cereus HSTUB 17 (108 CFU ml−1 @ 5 ml/plant), previously isolated T. harzianum (@5 mm size of four mycelial disk/plant) and aqueous leaf extracts of C. gigantea (1:1, w/v basis @ 40 ml/plant) were applied in the root zone following soil drenching method and found to reduce bacterial wilt incidence by 74.87, 66.67 and 66.67% at 30, 50 and 70 days after transplanting, respectively, in comparison with plants received only R. solanacearum (108 CFU ml−1 @ 5 ml/plant). The single application of B. cereus HSTUB 17, T. harzianum and C. gigantea also minimized wilt incidence by 21.16–37.34, 33.33 and 21.48–28.14%, respectively, on all the days of observations. The consortia of B. cereus HSTUB 17, T. harzianum and C. gigantea also resulted in maximum plant height (56.67 cm), the number of branches/plants (10.33), the number of fruits/plants (8.33) and fruit yield (25.56 ton/ha) in comparison with the plant exposed to R. solanacearum only. Conclusion: The findings of the study revealed the potentiality of consortia composed of B. cereus HSTUB 17, T. harzianum and C. gigantea for the eco-friendly management of bacterial wilt of brinjal for the first time in Bangladesh. [ABSTRACT FROM AUTHOR]

Summary: Fusarium wilt is the major biotic constraint responsible for substantial loss in the agricultural production and yield of safflower (Carthamus tinctorius L.). To better understand the symptomatology and etiology of wilt disease, safflower-growing fields of Karnataka and Maharashtra states in India were surveyed. The infected plants exhibited characteristic symptoms of wilt disease including browning of stem, chlorosis, and drooping of leaves. Fungal isolates obtained from infected parts of plants were morphologically characterized. Along with Fusarium oxysporum, another species of Fusarium was identified. This species produced buff to dark red colonies with aerial mycelia. Microconidia were clavate with a flattened base, aseptate, and 5.2–5.9 × 1.5–2.0 μm in size. Macroconidia were falcate to subfalcate, 3–5 septate, and 21.1–38.0 × 1.9–2.7 μm in size. Using internal transcribed spacer (ITS) of rDNA and translation elongation factor-1α (TEF-1α) genes, the identity of this species was confirmed as Fusarium proliferatum (Fp). Molecular phylogeny was inferred for all Fp isolates using ITS and TEF-1a sequences and they displayed close relatedness to Fp type material. The adult plants of susceptible cultivar of safflower (cv. Manjira) were inoculated with Fp spore suspension wherein the wilt disease was recapitulated. Morphologically identical Fp was isolated from the infected plants fulfilling Koch's postulates. This is a new record of wilt disease inflicted by Fp on safflower-growing fields of India. [ABSTRACT FROM AUTHOR]

One of the most harmful diseases that infect maize plants is Fusarium wilt caused by Fusarium oxysporum. The novelty of this study was to investigate the antifungal and plant growth-promoting properties of some rhizobacteria (PGPR). PGPR enhances plant growth and manages plant diseases. In this study, some bacterial isolates were isolated from the rhizosphere of rice plants and selected based on their ability to produce β-1,3 glucanase. The two bacterial isolates that produced higher concentrations of β-1,3 glucanase were selected to complete the study and identified by 16S rDNA sequences as Pseudomonas pseudoalcaligenes with accession number EU921258 and Bacillus pumilus with accession number EU921259. Different biochemical properties of the two bacterial isolates were investigated. Additionally, the effectiveness of P. pseudoalcaligene and B. pumilus against Fusarium oxysporum, which causes maize wilt disease was assessed. The results showed that P. pseudoalcaligenes and B. pumilus, either alone or in combination caused a significant reduction in the percentage of disease severity and an increment in the percentage of protection. In addition, infection with Fusarium caused a significant decrease in the morphological parameters, photosynthetic pigments, and cell membrane stability as compared to healthy control plants. However, lipid peroxidation, osmoprotectant compounds (soluble sugars, glycine betaine, and proline), secondary metabolites (phenol, flavonoid, and lignin content), and the enzymatic antioxidants increased significantly in infected plants as compared to healthy control plants. Furthermore, inoculation with P. pseudoalcaligenes and B. pumilus alone or in a combination caused significantly increased in the morphological parameters, photosynthetic pigment, and cell membrane stability in infected plants. Induction of β-1,3 glucanase gene in maize was not recorded in non-inoculated plants, but detected in inoculated plants with P. pseudoalcaligenes and B. pumilus alone or in combination as 2.4 kb bands on agarose gel electrophoresis. In conclusion, PGPR is regarded as an environmentally friendly method of protecting plants from pathogen infection and increasing plant growth without the use of pesticides, which cause a variety of environmental pollutions. [ABSTRACT FROM AUTHOR]

Applying organic amendments and bioagents is considered an ecofriendly practice to promote soil fertility and suppressiveness against many pathogens. This study determined the suppressiveness of seven different organic amendments and four bioagents against the cumin wilt disease at the Department of Plant Pathology, College of Agriculture, Jodhpur (Agriculture University Jodhpur) in the years 2020-2021. Among them, the lowest incidence was recorded in mustard cake (27.11%), neem cake (29.37%), groundnut cake (29.96%), and sesame cake (31.81%). Disease incidence was higher in other amendment applications like castor cake (33.21%) and cotton cake (33.14%). However, the disease incidence was much higher in controls (64.11%). Among bioagent treatments in vitro, Trichoderma harzianum (78.25%) and Trichoderma viride (72.69%) were the best at inhibiting the mycelial growth of Fusarium oxysporum f. spp. cumini compared to the treatment of Bacillus subtilis (55.34%). [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the antagonistic activity of Trichoderma spp. against wild pathogen Fusarium oxysporum F.28.1A, which causes wilt disease on sesame. Twenty-six isolates of Trichoderma spp. isolated from soil samples were tested to control F. oxysporum F.28.1A. Prescreening showed that five isolates were T-02B1, T-18B2, T-20B1, T-28B1, and T-29A1, based on the lowest values of colony radius of F. oxysporum F.28.1A. The selected isolates were identified by their ITS region as T. yunnanense T-02B1, T. lentiforme T-18B2, T. asperellum T-20B1, T. hamatum T-28B1, and T. hamatum T-29A1, with similarities around 96–100%. The isolates selected were able to produce enzymes including chitinase, exo-β-1,3-glucanase, and endo-β-1,3-glucanase at levels of 0.34–0.44, 0.017–0.034, and 0.032–0.121 UI · ml –1, respectively, which were considered to be a mechanism to prevent the growth of F. oxysporum F.28.1A. The isolates tested were applied in soil pots to prevent damage from F. oxysporum F.28.1A as a following experiment. The greenhouse experiment was arranged in a completely randomized design with 10 treatments, including a negative control, application of only F. oxysporum F.28.1A, application of both F. oxysporum F.28.1A and fungicide chemicals, application of both F. oxysporum F.28.1A and Trichoderma spp. DHCT, application of T. yunnanense T-02B1, application of T. lentiforme T-18B2, application of T. asperellum T-20B1, application of T. hamatum T-28B1, application of T. hamatum T-29A1 and a mixture of the five selected isolates of Trichoderma spp. with their total population equal to that in individual strain application. The results showed that the five mixed isolates of Trichoderma had a synergistic effect on the reduction of the disease’s prevalence by 35% compared to the negative control treatment.

Acacia mangium plantations in Sabah, Malaysia are seriously affected by a vascular wilt and canker disease caused by a species of Ceratocystis. A similar and devastating disease occurs in Indonesia and is caused by the fungal pathogen Ceratocystis manginecans. A closely related fungus, Ceratocystis fimbriata sensu stricto, is a common soil-borne pathogen of sweet potato (Ipomoea batatas) in areas of Malaysia where A. mangium is grown. This study characterised the species causing wilting on A. mangium and compared it with the I. batatas pathogen using DNA sequence-based comparisons used artificial inoculations to assess the effect of the A. mangium pathogen on Acacia auriculiformis and Acacia crassicarpa and considered the ability of the sweet potato pathogen to cause disease on the three Acacia species. DNA sequence comparisons confirmed that isolates from diseased A. mangium were C. manginecans and those on sweet potato were C. fimbriata s.s. Ceratocystis manginecans was pathogenic on all Acacia spp., with A. mangium being most susceptible followed by =A. auriculiformis and A. crassicarpa. Pathogenicity tests showed that C. fimbriata s.s. from sweet potato is not able to cause disease on any of the three Acacia spp. considered. This study also confirmed that C. manginecans is the primary cause of ceratocystis canker and wilt disease in Sabah and that the sweet potato fungus, C. fimbriata s.s., poses no threat to propagated Acacia spp. [ABSTRACT FROM AUTHOR]

Sweet pepper (Capsicum annuum L.), also known as bell pepper, is one of the most widely grown vegetable crops worldwide. It is attacked by numerous phytopathogenic fungi, such as Fusarium equiseti, the causal agent of Fusarium wilt disease. In the current study, we proposed two benzimidazole derivatives, including 2-(2-hydroxyphenyl)-1-H benzimidazole (HPBI) and its aluminum complex (Al−HPBI complex), as potential control alternatives to F. equiseti. Our findings showed that both compounds demonstrated dose-dependent antifungal activity against F. equiseti in vitro and significantly suppressed disease development in pepper plants under greenhouse conditions. According to in silico analysis, the F. equiseti genome possesses a predicted Sterol 24-C-methyltransferase (FeEGR6) protein that shares a high degree of homology with EGR6 from F. oxysporum (FoEGR6). It is worth mentioning that molecular docking analysis confirmed that both compounds can interact with FeEGR6 from F. equiseti as well as FoEGR6 from F. oxysporum. Moreover, root application of HPBI and its aluminum complex significantly enhanced the enzymatic activities of guaiacol-dependent peroxidases (POX), polyphenol oxidase (PPO), and upregulated four antioxidant-related enzymes, including superoxide dismutase [Cu-Zn] (CaSOD-Cu), L-ascorbate peroxidase 1, cytosolic (CaAPX), glutathione reductase, chloroplastic (CaGR), and monodehydroascorbate reductase (CaMDHAR). Additionally, both benzimidazole derivatives induced the accumulation of total soluble phenolics and total soluble flavonoids. Collectively, these findings suggest that the application of HPBI and Al−HPBI complex induce both enzymatic and nonenzymatic antioxidant defense machinery. [ABSTRACT FROM AUTHOR]

Natural infections of Verticillium spp. (Fungi, Ascomycota) on Ailanthus altissima have suggested to consider the biological control as a promising strategy to counteract this invasive plant, which is otherwise difficult to control by traditional mechanical and chemical treatments. Verticillium wilt is able to lead plants to death, throughout a pathogenic mechanism including vessel occlusions and production of degrading enzymes and phytotoxins. In this study, a 10 weeks open air pot experiment was set to investigate the ecophysiological and biochemical responses of Ailanthus trees artificially inoculated in the trunk with the V. dahliae strain VdGL16, previously isolated in Central Italy from the same host. Inoculated plants showed visible injuries starting from 2 weeks post inoculation (wpi), that progressively developed until a final severe defoliation. The fungal infection rapidly compromised the plant water status, and photosynthesis was impaired due to both stomatal and mesophyll limitations from 4 wpi, with subsequent detrimental effects also on PSII activity. Moreover, the disease altered the translocations of nutrients, as confirmed by cation and carbohydrate contents, probably due to a consumption of simple sugars and starch reserves without replacement of new photosynthesized. An accumulation of osmolytes (abscisic acid and proline) and phenylalanine (a precursor of phenylpropanoids) was also reported at 8 wpi, this being a response mechanism that needs to be further elucidated. However, the activation delay of such defence strategy inevitably did not avoid the premature defoliation of plants and the decline of physiochemical parameters, confirming the key role of Verticillium in Ailanthus decay. [ABSTRACT FROM AUTHOR]

Wilt disease caused by Phytophthora melonis infection is one of the most serious threats to Benincasa hispida production. However, the mechanism of the response of B. hispida to a P. melonis infection remains largely unknown. In the present study, two B. hispida cultivars with different degrees of resistance to P. melonis were identified: B488 (a moderately resistant cultivar) and B214 (a moderately susceptible cultivar). RNA-seq was performed on P. melonisinfected B488 and B214 12 hours post infection (hpi). Compared with the control, 680 and 988 DEGs were respectively detected in B488 and B214. A KEGG pathway analysis combined with a cluster analysis revealed that phenylpropanoid biosynthesis, plant-pathogen interaction, the MAPK signaling pathway-plant, and plant hormone signal transduction were the most relevant pathways during the response of both B488 and B214 to P. melonis infection, as well as the differentially expressed genes in the two cultivars. In addition, a cluster analysis of transcription factor genes in DEGs identified four genes upregulated in B488 but not in B214 at 6 hpi and 12 hpi, which was confirmed by qRT-PCR. These were candidate genes for elucidating the mechanism of the B. hispida response to P. melonis infection and laying the foundation for the improvement of B. hispida. [ABSTRACT FROM AUTHOR]

Fusarium wilt disease is the most important disease of cumin (Cuminum cyminum L.) and causes great damage to it every year. The present study was conducted to evaluate the response of 13 cumin genotypes to Fusarium wilt disease as a factorial experiment in a completely randomized design (genotype as the first factor and absence and presence of the pathogen as the second one) with three replications in the greenhouse of Research and Technology Institute of Plant Production, Shahid Bahonar University of Kerman during growing season of 2020-2021. The results showed that the interaction of genotype and treatment was statistically significant on most of the traits. The highest traits correlation was observed between plant dry weight and number of umbrellas per plant (0.92) under the absence of pathogen conditions and between plant height and number of seeds per plant (0.76) under the presence of pathogen conditions. Cluster analysis (Ward method) regarding the studied traits divided the genotypes into three groups under the absence of pathogen conditions and two groups under the presence of pathogen. Principal component analysis showed that the first two components could explain 80.13% (absence of pathogen) and 84.55% (presence of pathogen) of the variations. Also, biplot analysis showed high diversity of the genotypes as well as confirming the clustering results. The genotype E7r1b1 had the highest plant mortality ratio (100%) under the presence of pathogen. Under the absence of pathogen, the genotype g8r2b2 had the highest yield (0.20 g) and number (75.66) of seeds per plant. Yield and number of seeds per plant decreased significantly under the presence of pathogen. The highest seed yield (0.14 g) under the presence of pathogen was observed in the genotype 2-14-3. Based on the studied traits, the genotypes g5r2B1 and F12r1b1 had the lowest potential compared to the others under the both conditions. In general, the genotypes reacted differently under the absence and presence of pathogen conditions. The genotypes that revealed tolerance to the disease conditions could be introduced as sources of tolerance in further breeding programs. [ABSTRACT FROM AUTHOR]

Ralstonia solanacearum wilt disease causes significant economic losses to a number of crops worldwide, including eggplant (Solanum melongena L.). In this article plant growth promotions such as silver (Ag) nanoparticles (NPs), selenium (Se) NPs, and bimetallic Ag-Se NPs were used to combat the Ralstonia solanacearum wilt (RSW) disease and encourage growth-promoting strategies and resistance mechanisms in Solanum melongena L. Results clarified that the tested nano inducers against R. solanacearum (RS) have beneficial antibacterial. Bimetallic Ag-Se NPs (100 μg/mL) was the best treatment in reducing disease index (DI) by 17.5 and increasing the protection by 78.1 %, then Ag NPs and Se NPs, where the DI was 30 and 32.5 and protection by 62.5 % and 59.4 %, respectively. The potential resistance of developing eggplant plants was assessed using morphological characteristics, photosynthetic pigments, soluble carbohydrates, soluble protein, antioxidant enzyme activity, and isozymes. There was an increase in vegetative growth, photosynthetic pigments, soluble carbohydrates, and proteins in infected plants treated with all tested inducers, especially, bimetallic Ag-Se NPs. The amount of phenol content and the activity of antioxidant enzymes (PPO and POD) across diseased and healthy plants were recorded after applying all investigated inducers. The commercial use of a combination of tailored bimetallic Ag-Se NPs as nutritional therapy against R. solanacearum may be advised. • Ag NPs, Se NPs, and bimetallic Ag-Se NPs were used to combat Ralstonia solanacearum wilt disease. • The Ag-Se NPs were the best treatments in reducing the disease index. • The potential resistance was assessed using morphological characteristics, photosynthetic pigments, soluble carbohydrate, sloble protein, antioxidant enzyme activity, and isozymes. • It could be recommended the usage of Ag-Se NPs as therapeutic nutrients against R. solanacearum. [ABSTRACT FROM AUTHOR]

The vast majority of plant disease resistance (R) genes encode nucleotide binding site-leucine-rich repeat (NBS-LRR) proteins, which specifically determine the plant immune response and have been demonstrated to be targets of several microRNA (miRNA) families. The fungus Fusarium oxysporum f. sp. lycopersici (FOL) causes vascular wilt disease in tomato worldwide. Here, we explored a possible role for FGR3 in tomato defense against FOL. FRG3 is a predicted NBS-LRR like gene that is targeted by slmiR482e-3p, a member of slmiR482 miRNA family. Northern blot data demonstrated that all seven members of the slmiR482 family were regulated in diverse ways after infection by FOL. The ability of FRG3 to be regulated by slmiR482e-3p was confirmed at the transcript level by co-expression studies in Nicotiana benthamiana. A virus-induced gene silencing (VIGS) approach revealed that FRG3 confers resistance to the Motelle tomato cultivar. Taken together, our study has identified a novel R gene, FRG3, which is targeted by slmiR482e-3p at the transcript level, and is necessary for resistance to tomato wilt disease in planta.

Background: Identifying effective biological control agents against fungal pathogens and determining their mechanisms of action are important in the control of plant diseases., Results: In this study, we isolated an endophytic bacterial strain, GsB01, from the branches of asymptomatic Gleditsia sinensis. Multi-locus sequence analysis identified the strain as Bacillus velezensis. GsB01 exhibited significant antifungal activity against Thyronectria austroamericana, the causative agent of G. sinensis wilt. Liquid chromatography-mass spectrometry identified four consistently present antimicrobial compounds in GsB01 metabolite fractions with high antifungal activity: macrolactin A, bacillaene A, surfactin, and iturin. GsB01's active metabolite fractions altered the metabolic profiles of T. austroamericana, disrupting seven pathways, including arginine biosynthesis, nucleotide metabolism, purine metabolism, and the pentose phosphate pathway. Furthermore, absolute quantitative polymerase chain reaction analysis suggested that GsB01 may increase the abundance of endophytic bacteria in G. sinensis. The 16S rRNA amplicon sequencing revealed changes in the endophytic landscape in stems and roots following GsB01 introduction, particularly with significant variation in the dominant bacterial genera within the stems., Conclusion: The study highlights GsB01's potential against plant wilt and suggests that its antifungal activity is achieved by secreting antifungal metabolites. The study also recorded changes in the symbiotic microbiota within trees that had been infected with a pathogenic fungus and subsequently treated with an endophytic antagonistic bacterial strain. © 2024 Society of Chemical Industry., (© 2024 Society of Chemical Industry.)

Bioassay-guided isolation of a dihydroxy flavone from the cell extract of Penicillium EU0013 was carried out using preparative LCMS and the structure was interpreted using 1D and 2D NMR spectra. The fungus was fermented in three different nutrient media i.e. Glucose Nutrient Broth, Glucose Peptone Yeast Broth, and Yeast Extract Broth and the cell extract was obtained using organics. Comparative LCMS profiles of the fungus confirmed the enhanced production of dihydroxy flavone in GPYB media. In this study, the pathogenicity of the dihydroxy flavone is reported for the first time against Fusarium oxysporum f.sp. lycopersici , wilt causing pathogen of a tomato plant. In MIC experiments, the compound inhibited the pathogen at 80 µg mL -1 . Molecular docking studies of the compound with Fol tomatinase showed five binding interactions. These docking studies may help explore dihydroxy flavones as a lead for developing new fungicides to prevent wilt disease in tomatoes.

Fusarium wilt is among the major soil borne fungal diseases hindering sweet potato production in temperate regions of the world. Resistant cultivars are important for commercial production as the impact of Fusarium wilt is aggravating due to intensifying climate variability, thus the need for quick screening methods. The objectives of this study were to test a quick screening method at the early growth stage, to identify resistant parents, and to screen resultant progenies for resistance under glasshouse and field conditions. Virulent isolates of Fusarium oxysporum f. sp. batatas (PPRI15907) and F. oxysporum f. sp. vanillae (PPRI9458) were used. The soil was artificially inoculated and planted with month-old sweet potato plantlets. Visual leaf and stem disease assessments were recorded at 6 weeks after planting using an ordinal rating scale (0–3). Both leaf and stem disease assessment results indicated significant variation (P ≤ 0.05) in the disease reaction of the genotypes. Based on stem disease severity index (DSI) as determined from the quick screening, Bonita (4.2%) and Monate (8.3%) were classified as resistant, and Blesbok (66%) and Lethlabula (81%) as highly susceptible parents. Furthermore, DSI categorized the 92 progenies into 44 resistant, 21 moderately resistant, 13 moderately susceptible, seven susceptible and seven highly susceptible genotypes. The field experiment confirmed that 84% of genotypes that were identified to be resistant to Fusarium wilt under glasshouse conditions, were also resistant under field conditions. Thus the glasshouse method is reliable, efficient, and can screen large numbers of sweet potato genotypes for resistance against virulent Fusarium oxysporum isolates. [ABSTRACT FROM AUTHOR]

Plant pathogens employ secreted proteins, among which are effectors, to manipulate and colonize their hosts. A large fraction of effectors is translocated into host cells, where they can suppress defense signaling. Bacterial pathogens directly inject effectors into host cells via the type three secretion system, but it is little understood how eukaryotic pathogens, such as fungi, accomplish this critical process and how their secreted effectors enter host cells. The root-infecting fungus Fusarium oxysporum (Fo) secrets numerous effectors into the extracellular space. Some of these, such as Foa3, function inside the plant cell to suppress host defenses. Here, we show that Foa3 suppresses pattern-triggered defense responses to the same extent when it is produced in planta irrespective of whether the protein carries the PR1 secretory signal peptide or not. When a GFP-tagged Foa3 was targeted for secretion it localized, among other locations, to mobile subcellular structures of unknown identity. Furthermore, like the well-known cell penetrating peptide Arginine 9, Foa3 was found to deliver an orthotospovirus avirulence protein-derived peptide into the cytosol, resulting in the activation of the matching resistance protein. Finally, we show that infiltrating Foa3 into the apoplast results in strong suppression of the pattern-triggered immune responses, potentially indicating its uptake by the host cells in absence of a pathogen. [ABSTRACT FROM AUTHOR]

A survey of in vitro and in vivo sensitivity of Verticillium dahliae and Fusarium oxysporum to several commercial fungicides and biofungicides was undertaken. In in vitro assays, the tested isolate of V. dahliae proved to be very sensitive to difenoconazole (EC50 = 0.02 mg/l). However, under greenhouse conditions, the highest efficacy in V. dahliae control on inoculated pepper plants was recorded for a product based on thiophanate-methyl (83.10% compared to control). Among the tested fungicides, the lowest efficacy was recorded for a product based on azoxystrobin (23.10 %) with no significant difference compared to control (p > 0.05). In in vitro assays, the tested F. oxysporum isolate was the most sensitive to prochloraz (EC50 = 0.07 mg/l) and the least sensitive to fluopyram (EC50 = 1075.01 mg/l). In in vivo assay, the highest efficacy was achieved by products based on captan (95.60%), and the lowest by a product based on thiophanate-methyl (54.40%). Antagonistic activity of the bacterium B. subtilis under laboratory conditions was not satisfying. Also, the antifungal activity and spectrum of a tested product based on tee tree oil was not efficient in suppressing pepper wilting caused by V. dahliae and F. oxysporum.

Plant pathogens employ secreted proteins, among which are effectors, to manipulate and colonize their hosts. A large fraction of effectors is translocated into host cells, where they can suppress defense signaling. Bacterial pathogens directly inject effectors into host cells via the type three secretion system, but it is little understood how eukaryotic pathogens, such as fungi, accomplish this critical process and how their secreted effectors enter host cells. The root-infecting fungus Fusarium oxysporum (Fo) secrets numerous effectors into the extracellular space. Some of these, such as Foa3, function inside the plant cell to suppress host defenses. Here, we show that Foa3 suppresses pattern-triggered defense responses to the same extent when it is produced in planta irrespective of whether the protein carries the PR1 secretory signal peptide or not. When a GFP-tagged Foa3 was targeted for secretion it localized, among other locations, to mobile subcellular structures of unknown identity. Furthermore, like the well-known cell penetrating peptide Arginine 9, Foa3 was found to deliver an orthotospovirus avirulence protein-derived peptide into the cytosol, resulting in the activation of the matching resistance protein. Finally, we show that infiltrating Foa3 into the apoplast results in strong suppression of the pattern-triggered immune responses, potentially indicating its uptake by the host cells in absence of a pathogen.

Populus davidiana × Populus bolleana (PdPap) root rot caused by Fusarium oxysporum is a major disease in China. Controlling this disease requires extensive use of chemicals. The use of plant endophytes, such as Bacillus, may be a suitable alternative to chemical agents. In this study, we isolated a strain of Bacillus amyloliquefaciens (AW3) by thermal stimulation and confrontation method from fleshy tap roots of Brassica rapa L. We then determined its inhibitory effect on the growth of F. oxysporum (Fox68) and how it induces the disease resistance of PdPap. The confrontation area and roots were visualized using an optical microscope and a scanning electron microscope, respectively, and mycelial cell malformation, swelling, and distortion observed. AW3 and F. oxysporum were inoculated in a variety of combinations that reduced the disease level. PdPap defense-related enzymes, such as PAL, PPO, SOD, and CAT, increased significantly. Besides, several genes associated with plant defense and hormonal signal transduction were highly expressed. Under the biological stress of Fox68, AW3 directly acted on the hyphae of Fox68, reducing the infection of PdPap by Fox68 and promoting PdPap growth. AW3 also induced the accumulation of defense-related enzymes/genes that conferred resistance. Therefore, AW3 could serve as a bio-control agent of wilt disease caused by F. oxysporum in PdPap. [ABSTRACT FROM AUTHOR]

Sweet pepper (Capsicum annuum L.), also known as bell pepper, is one of the most widely grown vegetable crops worldwide. It is attacked by numerous phytopathogenic fungi, such as Fusarium equiseti, the causal agent of Fusarium wilt disease. In the current study, we proposed two benzimidazole derivatives, including 2-(2-hydroxyphenyl)-1-H benzimidazole (HPBI) and its aluminum complex (Al−HPBI complex), as potential control alternatives to F. equiseti. Our findings showed that both compounds demonstrated dose-dependent antifungal activity against F. equiseti in vitro and significantly suppressed disease development in pepper plants under greenhouse conditions. According to in silico analysis, the F. equiseti genome possesses a predicted Sterol 24-C-methyltransferase (FeEGR6) protein that shares a high degree of homology with EGR6 from F. oxysporum (FoEGR6). It is worth mentioning that molecular docking analysis confirmed that both compounds can interact with FeEGR6 from F. equiseti as well as FoEGR6 from F. oxysporum. Moreover, root application of HPBI and its aluminum complex significantly enhanced the enzymatic activities of guaiacol-dependent peroxidases (POX), polyphenol oxidase (PPO), and upregulated four antioxidant-related enzymes, including superoxide dismutase [Cu-Zn] (CaSOD-Cu), L-ascorbate peroxidase 1, cytosolic (CaAPX), glutathione reductase, chloroplastic (CaGR), and monodehydroascorbate reductase (CaMDHAR). Additionally, both benzimidazole derivatives induced the accumulation of total soluble phenolics and total soluble flavonoids. Collectively, these findings suggest that the application of HPBI and Al−HPBI complex induce both enzymatic and nonenzymatic antioxidant defense machinery.

Recently, Saudi growers have expanded their production of organic, soilless-grown strawberries (Fragaria × ananassa Duch.), but their production shows many difficulties associated with disease susceptibility. In October 2021, 45% of strawberry plants cv. "Festival" organically cultivated in Dammam city, Saudi Arabia (26°31'34.5"N 50°00'51.0"E) showed wilting symptoms. Typical symptoms were yellowing, rapid wilting, death of older leaves, stunting, and decreased roots. Vascular bundle necrosis and crown and root rot were also observed; plants eventually collapsed and died. Twenty symptomatic strawberry plants were sampled to isolate the pathogen. Pieces (4 × 4 mm) of the symptomatic tissues from crowns and roots were sanitized with 1% NaOCl (90 s), submerged in 70% alcohol (20 s), rinsed with sterile water (2x 30 s), placed on potato dextrose agar (PDA; Scharlau Chemie, Spain) and incubated at 25°C for 6 days. Next, we prepared single-spore cultures on PDA and synthetic nutrient-poor agar (SNA). On PDA media, pure cultures produced abundant aerial mycelium, with light pink or purple pigmentation in the medium after incubation at 25°C for 7 days. On SNA media, aerial microconidia were abundant cylindrical to ellipsoid hyaline with zero to one septate (3.8 - 5.9 × 1.3 - 2.5 μm, n = 50). Macroconidia were few, hyaline and falcate, with slightly curved apexes and 2 to 4 septate (18.9 - 27.5 × 3.3 - 4.6 μm, n = 50). Chlamydospores were roundish and terminal or intercalary. As Leslie and Summerell (2006) described, such morphological characteristics are typical of F. oxysporum. The isolates' identities were established by extracting DNA using the DNeasy Plant Mini kit (QIAGEN, Hilden, Germany). This was followed by amplification and sequencing of the internal transcribed spacer (ITS) (White et al., 1990), elongation factor 1-α (TEF1-α) (O'Donnell et al., 1998), and the ribosomal RNA intergenic spacer (IGS) (Canizares et al., 2015). The ITS, TEF1-α, and IGS sequences of an isolate Fof-10 were submitted to GenBank (PP564462, PP703242, and PP784894, respectively). BLAST analysis confirmed 99.71 and 100% identities to the ITS, TEF-1α, and IGS sequences of F. oxysporum (KU931552.1, OR640020.1, and FJ985519.1), respectively. All isolates tested were confirmed at the forma specialis fragariae, level using the specific primers FofraF/FofraR (Suga et al. 2013). The ∼239 bp amplicon was sequenced and submitted to GenBank (PP703243). Two-month-old healthy strawberry plants of cultivars "Festival," "Marquis," and "Monterey" were inoculated by dipping the roots in the spore suspension (107 conidia ml-1) for 15 min (Henry et al. 2017). There were five replicates for each cultivar. Plants dipped in water were used as a control treatment. The plants were transplanted in sterilized soil and placed in a greenhouse at 30/26°C (day/night). Within 4 to 6 weeks, inoculated plants showed severe wilting and discoloration of the internal crown tissue, while control plants were symptomless. The pathogen was re-isolated from the discolored vascular tissue onto PDA and identified morphologically and molecularly as the original one, thus fulfilling Koch's postulates. The test was repeated twice. This report confirms F. oxysporum f. sp. fragariae as a causal agent of Fusarium wilt of strawberries in Saudi Arabia. This pathogen was previously reported to cause the Fusarium wilt of strawberries in California (Dilla-Ermita et al., 2023). This disease has been observed in several hydroponic strawberry greenhouses in Saudi Arabia, with incidence ranging from 25% to 45% across multiple locations. Given this, proper strategies are needed to manage this disease and to be compatible with organic farming.

Fusarium wilt, caused by Fusarium oxysporum f.sp. dianthi (FOD), is one of the most devastating carnation diseases globally, resulting in significant crop loss (40-70%). The purpose of this study was to determine the efficacy of several fungicides against Fusarium wilt of carnation in vitro and in vivo under protected cultivation. The disease infected plant samples were collected, and pathogen isolates were confirmed through morphological and molecular techniques. The rDNA sequences of isolates had 97-100% similarity with other sequences of FOD available in Genbank and the isolates were identified as Fusarium oxysporum f.sp. dianthi. Phylogenetic analysis of rDNA sequences revealed 62-99% sequence similarity among the isolates. Further, we evaluated nine different fungicides against the virulent pathogenic isolate CFODTNAU1 under in vitro and in vivo. Three different concentrations such as 500, 1000 and 1500 ppm were evaluated on mycelial growth of the pathogen under in vitro and percent inhibition over control was calculated. Among the fungicides, three of them namely, tebuconazole 50% + trifloxystrobin 25% WG, tebuconazole 25.9% SC and azoxystrobin 23% EC completely inhibited (100% inhibition) the mycelial growth of the fungus in vitro. Under protected cultivation, application of tebuconazole 50% + trifloxystrobin 25% WG through root dipping and soil drenching @ 1.0 g/L recorded 11.11% of wilt incidence compared to control (29.71% wilt incidence), which was 59.99% reduction over control. Besides, this fungicide also increased the stem length, earliness of flowering and yield than the control and other treatments. Thus, the fungicide tebuconazole 50% + trifloxystrobin 25% WG can be used for amelioration and control of wilt disease in carnation. [ABSTRACT FROM AUTHOR]

This study was carried out to determine the effects of arbuscular mycorrhizal fungi (AMF), and salicylic acid (SA) on plant growth parameters and severity of wilt disease caused by Verticillium dahliae Kleb. in pepper. Effects of two different AMFs (Commercial AMF and Glomus intraradices) and two different SA doses (0.5 and 1 mM) were compared with untreated control plants after ten weeks. Both AMF species caused 62.08% and 69.07% root colonization, and the mycorrhizal dependency ratio changed from 9.08% to 59.37% in pepper plants. Commercial AMF caused a significant increase in morphological growth parameters, root colonization, mycorrhizal dependency rates and suppression of the disease severity. SA (1 mM) resulted in improved morphological growth parameters and suppression of the severity of the disease. Besides, SA and AMF applications were found to suppress the severity of Verticillium wilt disease by 21.8% and 56% in pepper plants, respectively. Thus, the applications of SA and AMF had positive contributions to the pepper plant's morphological development. [ABSTRACT FROM AUTHOR]

Hot pepper (Capsicum annuum L.) is an economically important crop in Ethiopia. Wide variability in hot pepper germplasm in Ethiopia is expected due to the presence of diverse environmental conditions and variation in farming systems. The present study was carried out to evaluate the resistance of 75 hot pepper accessions to wilt disease and assess their genetic diversity using SSR markers. Out of 75 accessions tested, the present study identified 23 accessions that showed resistance (R) with the value of 1-10% disease incidence. The genetic diversity assessment using 13 polymorphic SSR markers allowed the detection of 111 clear and scorable bands. The number of alleles per locus ranged from 5 to 13, with an average of 8.54. The PIC value ranged from 0.27 to 0.87 with an average of 0.59. The gene diversity indices were highly variable across SSR loci and ranged from 0.29 to 0.88 with mean genetic diversity of 0.62. Observed heterozygosity was also highly variable between loci (0.01-0.45) indicating that the accessions were not fixed to homozygosity. Furthermore, genetic diversity parameters were estimated among populations by grouping accessions based on their origin. Within populations, the PIC value ranged from 0.31 to 0.77. The genetic distances among the eight populations ranged from 0.15 to 0.48. The observed highest genetic diversity (0.80) in the Amhara region (Gojam) may indicate this area as the primary site for designing in situ conservation for this crop in Ethiopia. The research findings provide baseline information on disease resistance germplasm sources to be used for the breeding program, as well as the status of genetic diversity of the accessions for efficient conservation and proper utilization of the existing genetic resources in the country. [ABSTRACT FROM AUTHOR]

Eggplant (Solanum melongena L.) is an important vegetable that is widespread in tropical and subtropical regions. Given that it is a rich source of antioxidants, fibers, minerals, and vitamins, the eggplant is among the top five vegetables in the Asian and Mediterranean regions. The genus Fusarium is one of the fungal pathogens that can cause considerable injury to crop plants and grain crops, as well as diseases in humans and animals. The pathogenicity test and molecular analysis for the identification of the casual fungi of wilt disease of purple eggplant were carried out in 2020 at the Mycology Laboratory, Department of Biology, Udayana University, Bali, Indonesia, and Biology Research Center, LIPI, Bogor, Indonesia. The isolated fungi were identified on the basis of macroscopic, microscopic, and molecular characters. The Koch's postulate test also verified the identity of the disease-causing fungal pathogen. Observations based on morphological characters confirmed the genus Fusarium. The macroscopic characters of Fusarium included creamy white colony mycelia and rapid growth (3 cm in 3 days). Microscopic characters included sickle-shaped macroconidia (27-35 µm long) and oval microconidia (18 µm long). Macroconidia were more abundant than microconidia. The hyphae lacked chlamydospores. On the basis of molecular characters, the species was identified as Fusarium falciforme strain DTO 422-HB. These findings are important for managing and controlling wilt disease and enhancing productivity in eggplant. [ABSTRACT FROM AUTHOR]

Cotton is an important cash crop of Pakistan and is severely affected with wilt in cotton-growing areas of Punjab province. Research was carried out on two major pathogens of cotton Fusarium oxysporum f. sp. vasinfectum and Meloidogyne incognita and their possible role in wilt disease complex. During 2017-19, a survey of cotton growing areas of Punjab (Jhang, Multan, Vehari, Mianwali, Rahim Yar Khan, Bahawalpur, Kabir Wala, Dakota, Basti Dharik, Tibba Sultan Pur, Rajan Pur, Chak 27 (Layyah), Chak 99B (Layyah), Lodhran, Fateh Pur and Dagar Rohtass) was conducted to collect a sample on symptomology basis of yellowing of leaves, discoloured bark of lower part of the stem, blackened xylem vessel and wilting. Data were recorded on wilt disease incidence, prevalence, associated pathogens and root-knot nematodes. Prevalence of cotton wilt was recorded the maximum 85% in areas of Vehari, Kabir Wala and Rajan Pur while the maximum incidence in both Multan and Tibba Sultan Pur was 15%. Percentage association of wilting fungi was recorded from the soil, roots, stem and leaves on placing them in artificial media and soil dilution techniques were used to determine fungi in rhizosphere such as Fusarium oxysporum, Verticillium spp., Penicillium spp., Aspergillus spp., Rhizoctonia spp., Colletotrichum spp., Rhizopus spp., Mucor and Pythium. Root associated fungi were isolated by Hyphal tip method and isolated F. oxysporum, Rhizoctonia spp. and Pythium spp. From stem and leaf sample, F. oxysporum, Verticillium spp., Colletotrichum spp., Alternaria spp. and Botryodiplodia spp. were recorded. Relative density nematode was recorded from different locations and highest occurrence was observed in Bahawalpur (85%) by using different extraction methods. Eggs masses of root knot nematodes were staining by using Phloxin B and nematodes inside root system was done by using acid fuchsin. Nematode reproduction parameters like No. of J2/roots system, J2 in 100ml of soils, eggs masses/root system, females/roots system, galls/root system were recorded. Cotton wilt caused by the interaction of Fusarium and Root knot nematode is threat to cotton industry in Pakistan and it should be treated to avoid economic losses. [ABSTRACT FROM AUTHOR]