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Disease symptoms of Fusarium wilt of banana caused by 'subtropical' race 4 of Fusrium oxysporum f. sp. cubense (Foc) in South Africa (A) and 'tropical' race 4 in Malaysia (B). Affected plants wilt rapidly, older and then younger leaves become yellow and brown, and plants eventually die. In some cases, the base of pseudostems split (C). Internally, a deep golden discoloration of the inner rhizome develops (D), while the vascular bundles in the pseudostem will turn yellow to reddish-brown (E).(For interpretation of the references to color in this figure legend, the reader is referred to the web version of the article.)
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Fusarium oxysporum is an asexual fungal species that includes human and animal pathogens and a diverse range of nonpathogens. Pathogenic and nonpathogenic strains of this species can be distinguished from each other with pathogenicity tests, but not with morphological analysis or sexual compatibility studies. Substantial genetic diversity among iso...
Citations
... Among them, wilt pathogens are F. oxysporum, F. verticillioides, F. graminearum, and F. solani [71]. Based on economic damages, F. oxysporum is the most devastating pathogen which has been documented in more than 150 host plants such as cabbage, tomato, cotton, banana, watermelon, flax, onion, pea, tulip, etc. [72]. F. oxysporum causes virulence in plants due to the releases of small cysteine-rich proteins [73]. ...
Fusarium pathogens are causal agents of several crop diseases and produce harmful mycotoxins resulting in crop and yield reduction worldwide. Among crop diseases, Fusarium wilt, Fusarium head blight, and Fusarium root blight are mostly reported diseases in numerous vegetables, crops, and fruits and have posed pressure on current food production and safety. In addition, the production of mycotoxins further aggravates plant health and causes serious health risks in humans and animals through food chain contamination. Different management practices have been enlisted in this chapter to reduce or eradicate Fusarium wilt in different crops. Interestingly, various mechanisms developed by plants have also been highlighted to fight against Fusarium pathogens and limit the growth of mycotoxins. One of defence mechanisms is plant antioxidant mechanisms to reduce oxidative stress by increasing enzymatic and non-enzymatic antioxidants to maintain cellular homeostasis under Fusarium infection. The other defence response is through hormonal signalling to combat fungal pathogens. Different phytohormones such as salicylic acid, ethylene, jasmonate, abscisic acid, cytokinin, auxin, and other plant secondary metabolites play a crucial part in the reduction of Fusarium growth and inhibit mycotoxin production through defence-related genes. Further, the use of different pre-harvest and post-harvest strategies has been elucidated to enhance plant resistance and growth by decreasing fungal pathogenicity and virulence.
... The phylogenetic basis which explains the variations in the genetic structure of Foc regarding pathogenic specificity has been associated with horizontal gene transfer [24,39,44]. The data suggest that chromosome 14 of lineage-specific genomic regions (LS) harbors genes responsible for pathogenicity that are dispensable and can be transferred laterally between pathogens, including several polyphyletic clonal lines within the species complex [42] (although, to date, there is no published evidence that chromosome 14 exists in Foc). ...
Fusarium wilt caused by Fusarium oxysporum f. sp. cubense (Foc) is one of the most destructive diseases in banana farming worldwide. Knowledge of the factors of genetic diversity and virulence of the pathogen contributes to the development of resistant cultivars and management strategies based on exclusion. In this study, phenotypic traits such as virulence and aggressiveness in a sample of 52 Foc isolates were analyzed and their relationship to the presence of putative effectors of gene SIX (Secreted in Xylem) pathogenicity homologs was verified. The similarity matrix revealed three isolates that were closest to the standard Foc race 1 strain. Isolates 229A and 218A were selected according to their aggressiveness profile in ‘Grand Naine’ and ‘Prata-Anã’, respectively, to replace the standard isolate of race 1 in the resistance screening process carried out by the breeding program. Two homologs of the SIX8 gene, SIX8a and SIX8b, are present in isolates of Foc from Brazil, and the SIX8b gene correlates with avirulence in the cultivar ‘Grand Naine’ (Cavendish). These results are important to support the banana genetic breeding program by identifying sources of resistance to Foc and contributing to the establishment of the function of SIX effector proteins.
... F. oxysporum, strain 551, is a non-pathogenic strain for humans, isolated from a soil collection, in the Atlantic Forest biome (Piracicaba, São Paulo, Brazil, 22°42′3''S 47°38′3 ''W), collected on 03/01/2000. The F. oxysporum strain 551 was characterized according to its macromorphological and micromorphological characteristics (ESM Fig. S1) according to previously described methodologies [16,17]. Briefly, the fungal isolate was cultivated in PDA for 4 days at 28 °C, to analyze the macromorphological characteristics and micromorphologies of the vegetative and reproductive structures. ...
This study aimed to assess the activity of AgNPs biosynthesized by Fusarium oxysporum (bio-AgNPs) against multidrug-resistant uropathogenic Proteus mirabilis, and to assess the antibacterial activity of catheters coated with bio-AgNPs. Broth microdilution and time-kill kinetics assays were used to determine the antibacterial activity of bio-AgNPs. Catheters were coated with two (2C) and three (3C) bio-AgNPs layers using polydopamine as crosslinker. Catheters were challenged with urine inoculated with P. mirabilis to assess the anti-incrustation activity. MIC was found to be 62.5 µmol l-1, causing total loss of viability after 4 h and bio-AgNPs inhibited biofilm formation by 76.4%. Catheters 2C and 3C avoided incrustation for 13 and 20 days, respectively, and reduced biofilm formation by more than 98%, while the pristine catheter was encrusted on the first day. These results provide evidence for the use of bio-AgNPs as a potential alternative to combat of multidrug-resistant P. mirabilis infections.
... The phylogenetic basis which explains the variations in the genetic structure of Foc regarding the pathogenic specificity has been associated with horizontal gene transfer [24,39,44]. The data suggests that chromosome 14 of lineage-specific genomic regions (LS) harbor genes responsible for pathogenicity that are dispensable and can be transferred laterally between pathogens, including several polyphyletic clonal lines within the species complex [42], although, to date, there is no published evidence that chromosome 14 exists in Foc. ...
Fusarium wilt caused by Fusarium oxysporum f. sp. cubense (Foc) is one of the most destructive diseases in banana farming worldwide. Knowledge of the factors of genetic diversity and virulence of the pathogen contributes to the development of resistant cultivars and in management strategies based on exclusion. In this study, phenotypic traits such as virulence and aggressiveness in a sample of 52 Foc isolates, were analyzed and their relationship to the presence of putative effectors of gene SIX (Secreted in Xylem) pathogenicity homologues, verified. According to the dissimilarity matrix, there were three isolates closest to the standard Foc race 1 strain. Isolates 229A and 218A, were selected according to their aggressiveness profile in 'Grand Naine' and 'Prata-Anã', respectively, I order to replace the standard isolate of race 1 in the resistance screening process carried out by the breeding program. Two homologues of the SIX8 gene, SIX8a and SIX8b, are present in isolates of Foc from Brazil and the SIX8b gene correlates with avirulence in the cultivar ‘Grand Naine’ (Cavendish). These results are important to support the banana genetic breeding program by identification of sources of resistance to Foc and contribute in the establishment of the function of SIX effector proteins.
... In addition, Fusarium oxysporum is a huge species complex that includes plant infections. These pathogens target their attacks on a wide variety of species in a way that is host-specific (Fourie et al., 2011). In certain soils, referred to as favorable soils, soil-borne pathogens like Fusarium oxysporum are able to flourish and cause serious illnesses. ...
... Fusarium oxysporum Schlecht emend. Snyder & Hansen is a soil born, diverse and quite adaptive ascomycete fungus that includes pathogenic strains infecting human, animal and plants and a diverse range of nonpathogenic strains (Gordon and Martyn, 1997;Fourie et al., 2011). The plant pathogenic strains are divided into special forms or formae speciales based on host specificity (Fourie et al. 2011). ...
... Snyder & Hansen is a soil born, diverse and quite adaptive ascomycete fungus that includes pathogenic strains infecting human, animal and plants and a diverse range of nonpathogenic strains (Gordon and Martyn, 1997;Fourie et al., 2011). The plant pathogenic strains are divided into special forms or formae speciales based on host specificity (Fourie et al. 2011). The formae speciales Cubense of F. oxysporoum infects banana and Heliconia spp. ...
... The F. oxysporum is an important group of fungi, with more than 150 strains that infect plants (Fourie et al. 2011). These strains cause Fusarium Wilt (FW) and Fusarium Crown Root Rot (FCRR) in different plants (Mustaffa and Thangavelu 2011;Bharat and Sharma 2014;Dita et al. 2018;Srinivas et al. 2019;Kalman et al. 2020;Awere et al. 2021). ...
... The F. oxysporum was isolated from the stems of tomato plants that showed symptoms of Fusarium wilt (Fourie et al. 2011). The stem was divided into onemillimeter portions using a sterile scalpel. ...
Gitari FM, Githae EW, Kuria EK. 2023. Phytochemical analysis and antimicrobial activity of Tamarindus indica extracts against Fusarium oxysporum and Xanthomonas campestris. Intl J Trop Drylands 7: 73-82. Plant-pathogenic bacteria and fungi are a major threat to biodiversity and food security worldwide. The pathogens are difficult to control using cultural methods and have sometimes acquired resistance to conventional pesticides. This has necessitated the search for more efficient active compounds against them. One promising source of such compounds is tropical-medicinal plants such as Tamarindus indica L. This study first determined the phytochemical composition of T. indica extracts from different parts (leaves, bark, roots, and pods). Then it evaluated in-vitro the antimicrobial activity against plant pathogenic bacteria (Xanthomonas campestris) and fungi (Fusarium oxysporum). Crude extracts were obtained using different solvents (dichloromethane, methanol, and acetone). The analysis revealed the presence of nine pharmaco-active phytochemicals; methanol extracts had the highest concentrations of these phytochemicals. All extracts demonstrated inhibitory effects against F. oxysporum. However, the extracts did not show any antimicrobial effect against X. campestris. There was a significant difference (p<0.05) in the percentage of inhibition of F. oxysporum growth by different extracts. Generally, high growth inhibition was observed in media containing different plant extracts at 250 and 500 ppm concentrations. For acetone extracts, the highest inhibition (71.042%) was induced by root extract at a 250 ppm concentration, whereas for dichloromethane extracts, the highest inhibition (68.811%) was induced by 500 ppm of leaf extract. Methanol extracts from stem recorded the highest inhibition of 86.953% at concentrations of 125 ppm. This was followed by root extracts (75.169% inhibition) at 500 ppm. The T. indica, therefore, has great potential as a source of bio-pesticide for use in integrated pest management of F. oxysporum.
... For a long time, Foc TR4 was diagnosed through the observation of wilting symptoms on infected plants and testing for vegetative compatibility groups (VCGs) (Fourie et al., 2011;Sun et al., 1978). ...
... For a long time, Foc TR4 was diagnosed through the observation of wilting symptoms on infected plants and testing for vegetative compatibility groups (VCGs) (Fourie et al., 2011;Sun et al., 1978). ...
Fusarium wilt of banana, caused by the pathogen Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4), is a threat to food security as it affects the global banana industry. Control of this pathogen is complex due to the lack of resistant banana or plantain genotypes, lack of effective commercial fungicides, the production of chlamydospores, late appearance of symptoms in infected plants, high adaptability of the pathogen to diverse soil conditions and the polycyclic nature of the disease. Currently, the management strategy for Foc TR4 is exclusion and eradication, which is costly for the producer and the environment because the plants are treated with glyphosate and the affected area is quarantined for a long time. Thus, the development of early detection strategies for Foc TR4 from environmental samples and asymptomatic tissues with low inoculum concentration is essential; this would enable restriction of pathogen spread and minimize the environmental impact by eradication only in areas with accurate data of the pathogen's presence. In this study, three different PCR technologies (conventional PCR, quantitative PCR and droplet digital [dd] PCR) were evaluated for Foc TR4 detection in complex environmental samples. We report the development of a sensitive and specific ddPCR primer/probe set and protocols that can be used as a tool for Foc TR4 detection from symptomatic and asymptomatic plant tissue without prior DNA extraction. The limits of detection in drainage waters, footbaths and soil samples were evaluated using artificial inoculation assays. Finally, environmental samples from Foc TR4‐affected fields were analysed.
... Hafizi et al. (2013) also mentioned, that F. oxysporum has white mycelia like cotton and its macroconidia have 3-5 septa. Fourie et al. (2011) also confirmed that this fungus produces chlamydospores with smooth or rough spore surfaces and are formed singly or in pairs. ...
Fusarium oxysporum f.sp. lycopersici (FOL) is a significant threat to tomato plants with its cutinase enzyme playing a critical role in the penetration into plant root tissue. Addressing this issue requires the gathering of essential data. Molecular docking was used to see the interaction between ligand and cutinase structure, whereas the in vitro evaluation used the rhodamine B medium to see fluorescence light expression as an indicator of cutinase activity. The results of both methods revealed turmeric’s ability can disturb cutinase enzyme and its activity. Molecular docking revealed the type and value of binding interactions between turmeric’s natural components and the cutinase enzyme. This virtual simulation attempted to hypothesize that the ligands from turmeric could obstruct the active site of the cutinase structure in order to degrade the plant cutin polymer. The selected turmeric molecules were bisdemethoxycurcumin, calebin A, curcumin, and demethoxycurcumin, which had shown the ability to bind to the active site of cutinase, namely serine (Ser-142). After docking, these four compounds showed the lowest scores (negative), which indicated an efficient binding of the active site. Experiments were continued in the petri dishes and suggested that turmeric extract successfully expressed the fade of fluorescence light expression.
