Sample records for fusarium wilt pathogen

  1. Fusarium wilt of lentil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt of lentil is caused by the soil borne fungus Fusaium oxysporum f. sp. lentis. The pathogen is widespread. The disease shows symptoms of wilting, and stunted plants. Other symptoms include wilting of top leaves resemble water deficiency, shrinking and curling of leaves from the lower...

  2. Fusarium verticillioides: A new cotton wilt pathogen in Uzbekistan

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An increase in wilt has been observed in cotton fields in Uzbekistan. This prompted us to conduct a survey of Uzbek cotton fields for wilt over a five year period beginning in 2007. Twenty-four regions with different soil types and ecologies were screened. In 9 regions, over 45% of the plants dem...

  3. Fusarium Wilt of Orchids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt of orchids is highly destructive and economically limiting to the production of quality orchids that has steadily increased in many production facilities. Important crops such as phalaenopsis, cattleyas, and oncidiums appear to be especially susceptible to certain Fusarium species. Fu...

  4. Inhibitory Effect of Algal Extracts on Mycelial Growth of the Tomato-Wilt Pathogen, Fusarium oxysporum f. sp. lycopersici

    PubMed Central

    Kim, Jiyoung

    2008-01-01

    The present study was undertaken to explore the inhibitory effect of cyanobacterial extracts of Nostoc commune FA-103 against the tomato-wilt pathogen, Fusarium oxysporum f. sp. lycopersici. In an optimal medium, cell growth, antifungal activity, and antifungal compound production could be increased 2.7-fold, 4.1-fold, and 13.4-fold, respectively. A crude algal extract had a similar effect as mancozeb at the recommended dose, both in laboratory and pot tests. In vitro and in vivo fungal growth, spore sporulation and fungal infection of wilt pathogen in tomato seeds were significantly inhibited by cyanobacterial extracts. Nostoc commune FA-103 extracts have potential for the suppression of Fusarium oxysporum f. sp. lycopersici. PMID:23997634

  5. Detection of Fusarium wilt pathogens of Psidium guajava L. in soil using culture independent PCR (ciPCR)

    PubMed Central

    Mishra, Rupesh K.; Pandey, Brajesh K.; Muthukumar, M.; Pathak, Neelam; Zeeshan, Mohammad

    2012-01-01

    Traditional culturing methods take a long time for identification of pathogenic isolates. A protocol has been developed for the detection of Fusarium from soil samples in the early stage of infection. Seventeen soil samples from different locations were collected before the onset of rains to find out the presence of Fusarium spp. population present in the soil of guava orchards and to correlate its presence with incidence of wilt. A PCR based method was developed for the molecular characterization of Fusarium using Fusarium spp. specific primer. DNA extracted by this method was free from protein and other contaminations and the yield was sufficient for PCR amplification. The primer developed in this study was amplifying ?230 bp in all infected samples while not in healthy soil. The specificity and sensitivity of primer were tested on several Fusarium spp. and found that this primer was amplifying 10?6 dilution of the fungal DNA. The present study facilitates the rapid detection of Fusarium spp. from infected soil samples of guava collected from different agroclimatic regions in India. A rapid detection method for pathogens and a diagnostic assay for disease would facilitate an early detection of pathogen and lead to more effective control strategies. PMID:23961219

  6. RFLP analysis of rDNA-ITS regions of native non-pathogenic Fusarium oxysporum isolates and their field evaluation for the suppression of Fusarium wilt disease of banana

    Microsoft Academic Search

    R. Thangavelu; A. Jayanthi

    2009-01-01

    Fusarium wilt caused by Fusarium oxysporum f. sp. cubense is the most devastating disease of banana affecting commercial cultivars grown worldwide. An attempt has been made to identify\\u000a antagonistic, non-pathogenic Fusarium oxysporum (npFo) isolates from banana soil. A total of 200 rhizosphere soil samples were collected from different commercial cultivars, as\\u000a well as wild bananas. Forty Fusarium isolates were recovered,

  7. First Report on Fusarium Wilt of Zucchini Caused by Fusarium oxysporum, in Korea

    PubMed Central

    Choi, In-Young; Kim, Ju-Hee; Lee, Wang-Hyu; Park, Ji-Hyun

    2015-01-01

    Fusarium wilt of zucchini in Jeonju, Korea, was first noticed in May 2013. Symptoms included wilting of the foliage, drying and withering of older leaves, and stunting of plants. Infected plants eventually died during growth. Based on morphological characteristics and phylogenetic analyses of the molecular markers (internal transcribed spacer rDNA and translation elongation factor 1?), the fungus was identified as Fusarium oxysporum. Pathogenicity of a representative isolate was demonstrated via artificial inoculation, and it satisfied Koch's postulates. To our knowledge, this is the first report of F. oxysporum causing wilt of zucchini in Korea.

  8. First Report on Fusarium Wilt of Zucchini Caused by Fusarium oxysporum, in Korea.

    PubMed

    Choi, In-Young; Kim, Ju-Hee; Lee, Wang-Hyu; Park, Ji-Hyun; Shin, Hyeon-Dong

    2015-06-01

    Fusarium wilt of zucchini in Jeonju, Korea, was first noticed in May 2013. Symptoms included wilting of the foliage, drying and withering of older leaves, and stunting of plants. Infected plants eventually died during growth. Based on morphological characteristics and phylogenetic analyses of the molecular markers (internal transcribed spacer rDNA and translation elongation factor 1?), the fungus was identified as Fusarium oxysporum. Pathogenicity of a representative isolate was demonstrated via artificial inoculation, and it satisfied Koch's postulates. To our knowledge, this is the first report of F. oxysporum causing wilt of zucchini in Korea. PMID:26190927

  9. A Fusarium Wilt Resistance Gene in Gossypium barbadense and Its Effect on Root-Knot Nematode-Wilt Disease Complex.

    PubMed

    Wang, C; Roberts, P A

    2006-07-01

    ABSTRACT Fusarium wilt, caused by the soilborne pathogen Fusarium oxysporum f. sp. vasinfectum race 1, is a vascular disease in cotton (Gossypium spp.), and is a component of a disease complex with root-knot nematodes (Meloidogyne incognita). Genetic analysis of two interspecific crosses (G. barbadense Pima S-7 x G. hirsutum Acala NemX and Pima S-7 x Acala SJ-2) showed that one major gene (designated Fov1) with allele dosage effect conferred resistance to F. oxysporum f. sp. vasinfectum race 1 in Pima S-7. Two amplified fragment length polymorphism (AFLP) markers were linked to Fov1 in Pima S-7, with genetic distance from the gene of 9.3 and 14.6 centimorgans. Less severe wilt symptoms in Acala NemX than Acala SJ-2 indicated that Acala NemX possesses one or more minor genes contributing to delay of wilt symptoms. Highly resistant plants in F(2) and F(3) (Pima S-7 x NemX) families indicated transgressive segregation effects of minor genes in Acala NemX combined with Fov1 from Pima S-7. The effects of wilt and nematode resistance on the nematode-wilt disease complex were assayed with two inoculation methods. In the presence of both pathogens, wilt damage measured as shoot and root weight reductions was greatest on wilt- and nematode-susceptible Acala SJ-2 and least in root-knot nematode-resistant and wilt-susceptible Acala NemX. Intermediate damage occurred in wilt-resistant and root-knot nematode-susceptible Pima S-7. The results indicated that nematode resistance was more effective than wilt resistance in suppressing wilt symptoms when either resistance was present alone. Nematode resistance combined with intermediate wilt resistance, as in the F(1) (Pima S-7 x NemX), was highly effective in protecting plants from root-knot nematodes and race 1 of Fusarium wilt as a disease complex. PMID:18943146

  10. Incidence of Fusarium wilt in Cucumis sativus  L. is promoted by cinnamic acid, an autotoxin in root exudates

    Microsoft Academic Search

    S. F. Ye; J. Q. Yu; Y. H. Peng; J. H. Zheng; L. Y. Zou

    2004-01-01

    The effects of Fusarium oxysporum f. sp. cucumerinum, the pathogen causing Fusarium wilt in cucumber and cinnamic acid, a principal autotoxic component in the root exudates of cucumber (Cucumis sativus L.), on plant growth, Photosynthesis and incidence of Fusarium wilt in cucumber were studied in order to elucidate the interaction of autotoxins and soil-borne pathogens in the soil sickness. F. oxysporum. f. sp. cucumerinum

  11. In Search of Markers Linked to Fusarium Wilt Race 1 Resistance in Watermelon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt in watermelon, caused by the fungus Fusarium oxysporum f. sp. niveum (FON), is responsible for severe economic losses and is one of the most important soilborne pathogens limiting watermelon production in many areas of the world. FON, which attacks the vasculature system of watermelon...

  12. A highly efficient Agrobacterium mediated transformation system for chickpea wilt pathogen Fusarium oxysporum f. sp. ciceri using DsRed-Express to follow root colonisation.

    PubMed

    Islam, Md Nazrul; Nizam, Shadab; Verma, Praveen K

    2012-06-20

    The soil-borne fungus Fusarium oxysporum f. sp. ciceri (Foc) causes vascular wilt of chickpea (Cicer arietinum L.), resulting in substantial yield losses worldwide. Agrobacterium tumefaciens mediated transformation (ATMT) has served as a resourceful tool for plant-pathogen interaction studies and offers a number of advantages over conventional transformation systems. Here, we developed a highly efficient A. tumefaciens mediated transformation system for Foc. In addition, a binary vector for constitutive expression of red fluorescent protein (DsRed-Express) was used to study developmental stages and host-pathogen interactions. Southern hybridisation was performed to confirm the transformation event and the presence of T-DNA in selected hygromycin resistant transformants. Most of the transformants showed single copy integrations at random positions. Microscopic studies revealed significant levels of fluorescent protein, both in conidia and mycelia. Confocal microscopy of chickpea roots infected with the transformed Foc showed rapid colonisation. These studies will allow us to develop strategies to determine the mechanisms of Foc-chickpea interaction in greater detail and to apply functional genomics for the characterisation of involved genes at the molecular level either by insertional mutagenesis or gene knock-out. PMID:22397973

  13. Studies of a New Fusarium Wilt of Spinach in Texas. 

    E-print Network

    Taubenhaus, J. J. (Jacob Joseph)

    1926-01-01

    associated with Fusarium wilt. ...................... 21 1 1 Methods of control. .......................................... 21 j Summary .................................................. 22 I Acknowledgment... spinach wilt infects any of the parts of the plant above ground, although he points out that F~csarium spinaciae is an organism which invades the ' vascular system of the spinach root. The Fusarium here described, on the other hand, is found to invade...

  14. The effect of Gossypium C-genome chromosomes on resistance to Fusarium wilt in allotetraploid cotton.

    PubMed

    Becerra Lopez-Lavalle, L A; McFadden, H; Brubaker, C L

    2007-08-01

    Fusarium oxysporum f. sp. vasinfectum (Fov) has the potential to become the most economically significant pathogen of cotton in Australia. Although the levels of resistance present in the new commercial cultivars have improved significantly, they are still not immune and cotton breeders continue to look for additional sources of resistance. The native Australian Gossypium species represent an alternative source of resistance because they could have co-evolved with the indigenous Fov pathogens. Forty-six BC(3 ) G. hirsutum x G. sturtianum multiple alien-chromosome-addition-line (MACAL) families were challenged with a field-derived Fov isolate (VCG-01111). The G. hirsutum parent of the hexaploid MACAL is highly susceptible to fusarium wilt; the G. sturtianum parent is strongly resistant. Twenty-two of the BC(3) families showed enhanced fusarium wilt resistance relative to the susceptible G. hirsutum parent. Logistic regression identified four G. sturtianum linkage groups with a significant effect on fusarium wilt resistance: two linkage groups were associated with improved fusarium wilt resistance, while two linkage groups were associated with increased fusarium wilt susceptibility. PMID:17632700

  15. Tomato Fusarium wilt and its chemical control strategies in a hydroponic system

    Microsoft Academic Search

    Weitang Song; Ligang Zhou; Chengzong Yang; Xiaodong Cao; Liqun Zhang; Xili Liu

    2004-01-01

    Tomato (Lycopersicon esculentum Mill.) was cultivated in a hydroponic system with unlimited growth cultivation mode by using a deep flow technique. The identified wilt pathogen Fusarium oxysporum Klotz. was used to infect the plants. Seven fungicides, prochloraz, carbendazim, thiram, toclofos-methyl, hymexazol, azoxystrobin and carboxin, were tested in vitro for their inhibitory activities against the pathogen by mycelial growth inhibition with

  16. Wilts of the Watermelon and Related Crops: Fusarium Wilts of Cucurbits. 

    E-print Network

    Taubenhaus, J. J. (Jacob Joseph)

    1920-01-01

    cowpeas died badly from Fusarium wilt and ~kra only slightly), was planted to cowpeas, okra, cotton, squash. gourd, cashaw, watermc tomato, and cabbage. Thc object in this plot was to determine relationship, if any, of the cowpea and okra wilts... C C a. Watermelon sick field planted in 20 varieties of watermelons, nearly all of them wiped out by Fusarium wilt. This is indicated by the hareness of the field. The rows remaining healthy are okra, cowpeas, Irish potatoeo, tomatoes...

  17. Induction of systemic resistance by Pseudomonas fluorescens in radish cultivars differing in susceptibility to fusarium wilt, using a novel bioassay

    Microsoft Academic Search

    M. Leeman; J. A. van Pelt; F. M. den Ouden; M. Heinsbroek; P. A. H. M. Bakker; B. Schippers

    1995-01-01

    Pseudomonas fluorescens-mediated induction of systemic resistance in radish against fusarium wilt (Fusarium oxysporum f. sp.raphani) was studied in a newly developed bioassay using a rockwool system. In this bioassay the pathogen and bacterium were confirmed to be confined to spatially separate locations on the plant root, throughout the experiment. Pathogen inoculum obtained by mixing peat with microconidia and subsequent incubation

  18. Cross Pathogenicity of Fusarium oxysporum f. sp. betae on Sugar Beet and Common Bean

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt, also known as Fusarium yellows, is caused by the fungus Fusarium oxysporum. Fusarium oxysporum is a vascular pathogen with a broad host range including common bean (Phaseolus vulgaris L.) and sugar beet (Beta vulgaris L.) with formae speciales (f. sp.) defined by the ability to cause ...

  19. Y15_999FW, A DOMINANT SCAR MARKER LINKED TO THE FUSARIUM WILT RACE 1 (FW) RESISTANCE GENE IN PEA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt poses a significant economic problem in pea-growing regions of the Pacific Northwest and throughout the world. Fw, a pea gene conferring complete and specific resistance to the Fusarium wilt race 1 pathogen, has been characterized in previous studies. This report describes a 1082 bp SC...

  20. Discovery of Fusarium wilt race 4 resistance in cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt [Fusarium oxysporum f.sp. vasinfectum (FOV) Atk. Sny & Hans)] is a soil-inhabiting fungus that can survive for long periods in the absence of a host, making it impractical to eradicate from infested fields. This cotton host specific forms of the fungus is comprised of different genotyp...

  1. Pathogen profile update: Fusarium oxysporum

    Microsoft Academic Search

    CAROLINE B. MICHIELSE; MARTIJN REP

    2009-01-01

    Taxonomy: Kingdom Fungi; Phylum Ascomycota; Class Sordariomycetes; Order Hypocreales; Family Nectriaceae; genus Fusarium. Host range: Very broad at the species level. More than 120 different formae speciales have been identified based on specificity to host species belonging to a wide range of plant families. Disease symptoms: Initial symptoms of vascular wilt include vein clearing and leaf epinasty, followed by stunting,

  2. Control of Fusarium wilt in banana with Chinese leek

    PubMed Central

    Huang, Y.H.; Wang, R.C.; Li, C. H.; Zuo, C.W.; Wei, Y. R.; Zhang, L.; Yi, G.J.

    2012-01-01

    The inhibitory effects of Chinese leek(Allium tuberosum) on Fusarium oxysporum f. sp. cubense (Foc) and on Fusarium wilt incidence were studied in order to identify a potential efficient way to control the disease. Adopting the rotation system of Chinese leek-banana reduced the Fusarium wilt incidence and disease severity index by 88 %-97 % and 91 %-96 %, respectively, improved the crop value by 36 %-86 %, in an area heavily infested by Foc between 2007 and 2009. As a result of inoculation in the greenhouse, Chinese leek treatment reduced disease incidence and the disease severity index by 58 % and 62 %, respectively in the variety Baxi (AAA) and by 79 % and 81 %, respectively in the variety Guangfen NO.1 (ABB). Crude extracts of Chinese leek completely inhibited the growth of Foc race 4 on Petri dishes, suppressed the proliferation of the spores by 91 % and caused 87 % spore mortality. The findings of this study suggest that Chinese leek has the potential to inhibit Foc growth and Fusarium wilt incidence. This potential may be developed into an environmentally friendly treatment to control Fusarium wilt of banana. PMID:23144534

  3. Combining Fluorescent Pseudomonas spp. Strains to Enhance Suppression of Fusarium Wilt of Radish

    Microsoft Academic Search

    Marjan de Boer; Ientse van der Sluis; Leendert C. van Loon; Peter A. H. M. Bakker

    1999-01-01

    Fusarium wilt diseases, caused by the fungus Fusarium oxysporum, lead to significant yield losses of crops. One strategy to control fusarium wilt is the use of antagonistic, root-colonizing Pseudomonas spp. It has been demonstrated that different strains of these bacteria suppress disease by different mechanisms. Therefore, application of a mixture of these biocontrol strains, and thus of several suppressive mechanisms,

  4. Identification of quantitative trait loci contributing to Fusarium wilt resistance on an AFLP linkage map of flax (Linum usitatissimum)

    Microsoft Academic Search

    W. Spielmeyer; A. G. Green; D. Bittisnich; N. Mendham; E. S. Lagudah

    1998-01-01

    An AFLP genetic linkage map of flax (Linum usitatissimum) was used to identify two quantitative trait loci (QTLs) on independent linkage groups with a major effect on resistance\\u000a to Fusarium wilt, a serious disease caused by the soil pathogen Fusarium oxysporum (lini). The linkage map was constructed using a mapping population from doubled-haploid (DH) lines. The DH lines were derived

  5. Commercial and improved germplasm evaluations for Fusarium wilt, FOV race 1 with root-knot nematodes and race 4

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Host plant resistance is the most economic and effective strategy for Fusarium wilt control. To implement steps to develop resistant germplasm to this pathogen, existing commercial Acala, non-Acala Upland (Gossypium hirsutum L.) and Pima (G. barbadense) cultivars, as well as improved germplasm were ...

  6. Elite-upland cotton germplasm-pool assessment of Fusarium wilt resistance in California

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Host-plant resistance is currently the most economic and effective strategy for managing Fusarium wilt [Fusarium oxysporum f. sp. vasinfectum (FOV)] disease. Over the past nine years, a new race of Fusarium (FOV race 4) has increasingly impacted cotton (Gossypium spp.) in production fields in the Sa...

  7. Extracellular chitinases of fluorescent pseudomonads antifungal to Fusarium oxysporum f. sp. dianthi causing carnation wilt.

    PubMed

    Ajit, Naosekpam Singh; Verma, Rajni; Shanmugam, V

    2006-04-01

    Vascular wilt of carnation caused by Fusarium oxysporum f. sp. dianthi (Prill. & Delacr.) W. C. Synder & H.N. Hans inflicts substantial yield and quality loss to the crop. Mycolytic enzymes such as chitinases are antifungal and contribute significantly to the antagonistic activity of fluorescent pseudomonads belonging to plant-growth-promoting rhizobacteria. Fluorescent pseudomonads antagonistic to the vascular wilt pathogen were studied for their ability to grow and produce chitinases on different substrates. Bacterial cells grown on chitin-containing media showed enhanced growth and enzyme production with increased anti-fungal activity against the pathogen. Furthermore, the cell-free bacterial culture filtrate from chitin-containing media also significantly inhibited the mycelial growth. Both the strains and their cell-free culture filtrate from chitin-amended media showed the formation of lytic zones on chitin agar, indicating chitinolytic ability. Extracellular proteins of highly antagonistic bacterial strain were isolated from cell-free extracts of media amended with chitin and fungal cell wall. These cell-free conditioned media contained one to seven polypeptides. Western blot analysis revealed two isoforms of chitinase with molecular masses of 43 and 18.5 kDa. Further plate assay for mycelial growth inhibition showed the 43-kDa protein to be antifungal. The foregoing studies clearly established the significance of chitinases in the antagonism of fluorescent pseudomonads, showing avenues for possible exploitation in carnation wilt management. PMID:16550458

  8. Biological control of Fusarium wilt of tomato with Fusarium equiseti GF191 in both rock wool and soil systems

    Microsoft Academic Search

    Hayato Horinouchi; Hideki Watanabe; Yoshihiro Taguchi; Ahmed Muslim; Mitsuro Hyakumachi

    The plant growth-promoting fungus (PGPF) Fusarium equiseti GF191 was tested for its ability to control Fusarium wilt of tomato (FWT) caused by Fusarium oxysporum f. sp. lycopersici (FOL) in both a hydroponic rock wool and soil system. F. equiseti effectively controlled FWT, with protective effects based on disease severity of 66.7–88.6% in four experiments. The numbers\\u000a of colony-forming units of

  9. Comparative Genomics Yields Insights into Niche Adaptation of Plant Vascular Wilt Pathogens

    PubMed Central

    Klosterman, Steven J.; Subbarao, Krishna V.; Kang, Seogchan; Veronese, Paola; Gold, Scott E.; Thomma, Bart P. H. J.; Chen, Zehua; Henrissat, Bernard; Lee, Yong-Hwan; Park, Jongsun; Garcia-Pedrajas, Maria D.; Barbara, Dez J.; Anchieta, Amy; de Jonge, Ronnie; Santhanam, Parthasarathy; Maruthachalam, Karunakaran; Atallah, Zahi; Amyotte, Stefan G.; Paz, Zahi; Inderbitzin, Patrik; Hayes, Ryan J.; Heiman, David I.; Young, Sarah; Zeng, Qiandong; Engels, Reinhard; Galagan, James; Cuomo, Christina A.; Dobinson, Katherine F.; Ma, Li-Jun

    2011-01-01

    The vascular wilt fungi Verticillium dahliae and V. albo-atrum infect over 200 plant species, causing billions of dollars in annual crop losses. The characteristic wilt symptoms are a result of colonization and proliferation of the pathogens in the xylem vessels, which undergo fluctuations in osmolarity. To gain insights into the mechanisms that confer the organisms' pathogenicity and enable them to proliferate in the unique ecological niche of the plant vascular system, we sequenced the genomes of V. dahliae and V. albo-atrum and compared them to each other, and to the genome of Fusarium oxysporum, another fungal wilt pathogen. Our analyses identified a set of proteins that are shared among all three wilt pathogens, and present in few other fungal species. One of these is a homolog of a bacterial glucosyltransferase that synthesizes virulence-related osmoregulated periplasmic glucans in bacteria. Pathogenicity tests of the corresponding V. dahliae glucosyltransferase gene deletion mutants indicate that the gene is required for full virulence in the Australian tobacco species Nicotiana benthamiana. Compared to other fungi, the two sequenced Verticillium genomes encode more pectin-degrading enzymes and other carbohydrate-active enzymes, suggesting an extraordinary capacity to degrade plant pectin barricades. The high level of synteny between the two Verticillium assemblies highlighted four flexible genomic islands in V. dahliae that are enriched for transposable elements, and contain duplicated genes and genes that are important in signaling/transcriptional regulation and iron/lipid metabolism. Coupled with an enhanced capacity to degrade plant materials, these genomic islands may contribute to the expanded genetic diversity and virulence of V. dahliae, the primary causal agent of Verticillium wilts. Significantly, our study reveals insights into the genetic mechanisms of niche adaptation of fungal wilt pathogens, advances our understanding of the evolution and development of their pathogenesis, and sheds light on potential avenues for the development of novel disease management strategies to combat destructive wilt diseases. PMID:21829347

  10. Increased soil suppressiveness to Fusarium wilt of flax after addition of municipal solid waste compost

    Microsoft Academic Search

    Claire Serra-Wittling; Sabine Houot; Claude Alabouvette

    1996-01-01

    The suppressiveness of a loamy soil amended with municipal solid waste compost to Fusarium wilt of flax (caused by Fusarium oxysporum f. sp. lini) was studied. The soil was moderately conducive to the disease, with an estimated half life time (HLT) of the flax population of 41 days. Heat-treatment made the soil highly conducive (HLT of 28 days). Compost addition

  11. Inheritance and QTL mapping of Fusarium wilt race 4 resistance in cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diseases such as Fusarium wilt [Fusarium oxysporum f.sp. vasinfectum (FOV) Atk. Sny & Hans)] represent expanding threats to cotton production. Integrating disease resistance into high-yielding, high-fiber quality cotton (Gossypium spp.) cultivars is one of the most important objectives in cotton bre...

  12. A major quantitative trait locus is associated with Fusarium Wilt Race 1 resistance in watermelon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt is a major disease of watermelon caused by the soil-borne fungus Fusarium oxysporum Schlechtend.:Fr. f. sp. niveum (E.F. Sm.) W.C. Snyder & H.N. Hans (Fon). A genetic population of 186 F3 families (24 plants in each family) exhibited continuous segregation for Fon race 1 response. Geno...

  13. The influence of Trichoderma harzianum on the root-knot Fusarium wilt complex in cotton.

    PubMed

    Yang, H; Powell, N T; Barker, K R

    1976-01-01

    Wilt-susceptible cultivar 'Rowden' cotton was inoculated wilh Meloidogyne incognita (N), Trichoderma harzianum (T), and Fusarium oxysporum f. sp. vasinfectum (F) alone and in all combinations in various time sequences. Plants inoculated with F alone or in combination with T did not develop wilt, Simultaneous inoculation of 7-day-old seedlings with all three organisms (NTF) produced earliest wilt. However, plants receiving nematodes at 7 days and Fusarium and Trichoderma at 2 or 4 weeks later (N-T-F, N-TF) developed the greatest wilt between 49-84 days after initial nematode inoculation. During the same period, Fusarium added 4 weeks after initial nematode inoculation (N-F) and Fusarium added 4 weeks after initial simultaneous inoculation of nematode and Trichoderma (NT-F) produced the least wilt. The addition of Fusarium inhibited nematode reproduction. Simultaneous inoculation with nematodes and Trichoderma (NT-) resulted in the greatest root gall development, whereas nematodes alone produced the greatest number of larvae. In comparison with noninoculated controls (CK), treatments involving all three organisms inhibited plant growth, plants inoculated with the nematode alone (N-) or with nematodes and Trichoderma (NT-) simultaneously had greatest root weight. Any treatment involving the nematode resulted in fewer bolls per plant and greater necrosis on roots than the noninoculated checks. PMID:19308202

  14. The Influence of Trichoderma harzianum on the Root-knot Fusarium Wilt Complex in Cotton

    PubMed Central

    Yang, Henry; Powell, N. T.; Barker, K. R.

    1976-01-01

    Wilt-susceptible cultivar 'Rowden' cotton was inoculated wilh Meloidogyne incognita (N), Trichoderma harzianum (T), and Fusarium oxysporum f. sp. vasinfectum (F) alone and in all combinations in various time sequences. Plants inoculated with F alone or in combination with T did not develop wilt, Simultaneous inoculation of 7-day-old seedlings with all three organisms (NTF) produced earliest wilt. However, plants receiving nematodes at 7 days and Fusarium and Trichoderma at 2 or 4 weeks later (N-T-F, N-TF) developed the greatest wilt between 49-84 days after initial nematode inoculation. During the same period, Fusarium added 4 weeks after initial nematode inoculation (N-F) and Fusarium added 4 weeks after initial simultaneous inoculation of nematode and Trichoderma (NT-F) produced the least wilt. The addition of Fusarium inhibited nematode reproduction. Simultaneous inoculation with nematodes and Trichoderma (NT-) resulted in the greatest root gall development, whereas nematodes alone produced the greatest number of larvae. In comparison with noninoculated controls (CK), treatments involving all three organisms inhibited plant growth, plants inoculated with the nematode alone (N-) or with nematodes and Trichoderma (NT-) simultaneously had greatest root weight. Any treatment involving the nematode resulted in fewer bolls per plant and greater necrosis on roots than the noninoculated checks. PMID:19308202

  15. Induction of Systemic Resistance of Benzothiadiazole and Humic Acid in Soybean Plants Against Fusarium Wilt Disease

    PubMed Central

    Ismail, Mamdoh Ewis; Morsy, Kadry Mohamed

    2011-01-01

    The ability of benzothiadiazole (BTH) and/or humic acid (HA) used as seed soaking to induce systemic resistance against a pathogenic strain of Fusarium oxysporum was examined in four soybean cultivars under greenhouse conditions. Alone and in combination the inducers were able to protect soybean plants against damping-off and wilt diseases compared with check treatment. These results were confirmed under field conditions in two different locations (Minia and New Valley governorates). The tested treatments significantly reduced damping-off and wilt diseases and increased growth parameters, except the number of branches per plant and also increased seed yield. Application of BTH (0.25 g/L) + HA (4 g/L) was the most potent in this respect. Soybean seed soaking in BTH + HA produced the highest activities of the testes of oxidative enzymes followed by BTH in the four soybean cultivars. HA treatment resulted in the lowest increases of these oxidative enzymes. Similar results were obtained with total phenol but HA increased total phenol more than did BTH in all tested cultivars. PMID:22783118

  16. Compost and Glomus mosseae for Management of Bacterial and Fusarium Wilts of Tomato

    Microsoft Academic Search

    L. B. Taiwo; D. T. Adebayo; O. S. Adebayo; J. A. Adediran

    2007-01-01

    Bacterial and fungal wilts cause considerable yield loss in tomato (Lycopersicum esculentumMill.), and require sustainable control strategies to reduce their incidence. Tomato was inoculated with the arbuscular mycorrhizal fungus Glomus mosseae(Nicolson & Gerdemann) Gerd. et Trappe, and treated with organic and inorganic fertilizers to determine effects on severity of tomato wilt caused by Ralstonia solanacearum(Smith) and Fusarium oxysporumSchlecht. f. sp.

  17. Mapping Fusarium wilt race 1 resistance genes in cotton by inheritance, QTL and sequencing composition.

    PubMed

    Ulloa, Mauricio; Wang, Congli; Hutmacher, Robert B; Wright, Steven D; Davis, R Michael; Saski, Christopher A; Roberts, Philip A

    2011-07-01

    Knowledge of the inheritance of disease resistance and genomic regions housing resistance (R) genes is essential to prevent expanding pathogen threats such as Fusarium wilt [Fusarium oxysporum f.sp. vasinfectum (FOV) Atk. Sny & Hans] in cotton (Gossypium spp.). We conducted a comprehensive study combining conventional inheritance, genetic and quantitative trait loci (QTL) mapping, QTL marker-sequence composition, and genome sequencing to examine the distribution, structure and organization of disease R genes to race 1 of FOV in the cotton genome. Molecular markers were applied to F(2) and recombinant inbred line (RIL) interspecific mapping populations from the crosses Pima-S7 (G. barbadense L.) × 'Acala NemX' (G. hirsutum L.) and Upland TM-1 (G. hirsutum) × Pima 3-79 (G. barbadense), respectively. Three greenhouse tests and one field test were used to obtain sequential estimates of severity index (DSI) of leaves, and vascular stem and root staining (VRS). A single resistance gene model was observed for the F(2) population based on inheritance of phenotypes. However, additional inheritance analyses and QTL mapping indicated gene interactions and inheritance from nine cotton chromosomes, with major QTLs detected on five chromosomes [Fov1-C06, Fov1-C08, (Fov1-C11 ( 1 ) and Fov1-C11 ( 2)) , Fov1-C16 and Fov1-C19 loci], explaining 8-31% of the DSI or VRS variation. The Fov1-C16 QTL locus identified in the F(2) and in the RIL populations had a significant role in conferring FOV race 1 resistance in different cotton backgrounds. Identified molecular markers may have important potential for breeding effective FOV race 1 resistance into elite cultivars by marker-assisted selection. Reconciliation between genetic and physical mapping of gene annotations from marker-DNA and new DNA sequences of BAC clones tagged with the resistance-associated QTLs revealed defenses genes induced upon pathogen infection and gene regions rich in disease-response elements, respectively. These offer candidate gene targets for Fusarium wilt resistance response in cotton and other host plants. PMID:21533837

  18. Efficacy of bacterial antagonists and different commercial products against Fusarium wilt on rocket

    Microsoft Academic Search

    K. Srinivasan; G. Gilardi; A. Garibaldi; M. L. Gullino

    2009-01-01

    Seven experimental trials were carried out to evaluate the efficacy of the bacterial strains Achromobacter xylosoxydans AM1 and Serratia sp. DM1 obtained from suppressive soils and from soilless used rockwool substrates (Pseudomonas putida FC6B, Pseudomonas sp. FC7B, Pseudomonas putida FC8B, Pseudomonas sp. FC9B and Pseudomonas sp. FC24B) against Fusarium wilt on rocket caused by Fusarium oxysporum ff. spp. raphani and

  19. Morphological and molecular characterization of melon accessions resistant to Fusarium wilts

    Microsoft Academic Search

    A. Oumouloud; M. S. Arnedo-Andrés; R. González-Torres; J. M. Álvarez

    2009-01-01

    Fusarium wilt incited by Fusarium oxysporum f. sp. melonis (F.o.m) is one of the most widespread and devastating melon diseases. While resistance to physiological races 0, 1, and 2\\u000a is relatively frequent in different botanical varieties, sources of resistance to race 1,2 are restricted to a few Far-Eastern\\u000a accessions. In this work, the results of a screening for resistance to

  20. Wilting of date palm branches by Fusarium oxysporum in south of Iran and its control managements with soil solarization method.

    PubMed

    Saremi, H; Okhovvat, S M; Ashrafi, S J

    2007-01-01

    Wilting of some branches in nurseries and orchards of date palm were studied in south of Iran including Ahvaz and Abadan cities in 2005-2006 years. Different infected plants were visited and samples showing symptoms including wilting or death of branches collected from various areas and transferred to laboratory. Samples were cultured in common media (PDA) and different fungi were studied and identified. The most frequently isolated pathogen was Fusarium oxysporum which caused wilting of some branches of date palm seedling or trees in studied areas. Results showed that the disease caused main losses where date palm cuttings were cultured in infected soils, previously cropped to susceptible plants. Since chemical control was not managed the disease, soil disinfestations by soil solarization method was carried in Ahvaz as the warmer climate in studied areas to control the pathogen. Application of this method reduced population density of the pathogen from 1800 CFU -g/soil to 600 after 5 week. This method was simple, effective, non negative side and economic which can be used in nearly warm areas. PMID:18396818

  1. Beltwide breeders' elite-Upland germplasm-pool assessment of Fusarium wilt (FOV) races 1 & 4 in California.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Host-plant resistance is currently the most economic and effective strategy for managing Fusarium wilt [Fusarium oxysporum f. sp. vasinfectum (FOV)] in the San Joaquin Valley (SJV) of California. Recently, a strain of Fusarium (race 4) was identified in the SJV that damages most cultivars of Pima co...

  2. Biological Control of Fusarium Wilt on Cotton by Use of Endophytic Bacteria

    Microsoft Academic Search

    C. Chen; E. M. Bauske; G. Musson; R. Rodriguezkabana; J. W. Kloepper

    1995-01-01

    One hundred seventy bacterial strains isolated from internal tissues of cotton, 49 strains with known biological control activity against Rhizoctonia solani in cotton, and 25 strains known to induce systemic resistance to Collectotrichum orbiculare in cucumber, were screened for biological control potential against vascular wilt of cotton caused by Fusarium oxysporum f. sp. vasinfectum. The strains were introduced as endophytes

  3. Evaluations of Fusarium wilt resistance in Upland cotton from Uzbek cotton germplasm resources.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium oxysporum f. sp. vasinfectum Atk. Sny & Hans (FOV), in combination with Verticillium dahliae Kleb, causes a wilt disease complex in cotton that significantly reduces yield. A highly virulent strain of FOV, No. 316, was isolated that caused up to 80% plant death in commercial cotton in Uzbe...

  4. Evaluation of the pathogenicity of Fusarium graminearum and Fusarium pseudograminearum on soybean seedlings under controlled conditions

    Microsoft Academic Search

    A. G. Xue; E. Cober; H. D. Voldeng; C. Babcock; R. M. Clear

    2007-01-01

    Fusarium graminearum, the cause of fusarium head blight of small-grain cereals and of gibberella ear rot of corn, has recently been reported to attack soybean, causing root rot and pod blight. A morphologically similar species, Fusarium pseudograminearum, is also an important pathogen of the roots and crown of cereals, but its pathogenicity against soybean has not been tested yet. Pathogenicity

  5. Influence of plant root exudates, germ tube orientation and passive conidia transport on biological control of fusarium wilt by strains of nonpathogenic Fusarium oxysporum.

    PubMed

    Mandeel, Qaher A

    2006-03-01

    In earlier studies, biological control of Fusarium wilt of cucumber induced by Fusarium oxysporum f. sp. cucumerinum was demonstrated using nonpathogenic strains C5 and C14 of Fusarium oxysporum. Strain C14 induced resistance and competed for infection sites whether roots were wounded or intact, whereas strain C5 required wounds to achieve biocontrol. In the current work, additional attributes involved in enhanced resistance by nonpathogenic biocontrol agents strains to Fusarium wilt of cucumber and pea were further investigated. In pre-penetration assays, pathogenic formae specials exhibited a significantly higher percentage of spore germination in 4-day-old root exudates of cucumber and pea than nonpathogens. Also, strain C5 exhibited the lowest significant reduction in spore germination in contrast to strain C14 or control. One-day-old cucumber roots injected with strain C14 resulted in significant reduction in germ tube orientation towards the root surface, 48-96 h after inoculation with F. o. cucumerinum spores, whereas strain C5 induced significantly lower spore orientation of the pathogen and only at 72 and 96 h after inoculation. In post-penetration tests, passive transport of microconidia of pathogenic and nonpathogens in stems from base to apex were examined when severed plant roots were immersed in spore suspension. In repeated trials, strain C5, F. o. cucumerinum and F. o. pisi were consistently isolated from stem tissues of both cucumber and pea at increasing heights over a 17 days incubation period. Strain C14 however, was recovered at a maximum translocation distance of 4.6 cm at day 6 and later height of isolation significantly declined thereafter to 1.2 cm at day 17. In pea stem, the decline was even less. Significant induction of resistance to challenge inoculation by the pathogen in cucumber occurred 72 and 96 h after pre-inoculation with biocontrol agents. Nonetheless, strain C14 induced protection as early as 48 h and the maximum resistance was reached at 96 h. The presented data confirm the previous findings that attributes important for nonpathogenic fusaria to induce resistant are: rapid spore germination and orientation in response to root exudate; active root penetration and passive conidia transport in stem to initiate defence reaction without pathogenicity and enough lag period between induction and challenge inoculation. Strain C14 possesses all these qualifications and hence its ability to enhance host resistance is superior than strain C5. PMID:16482390

  6. Fusarium avenaceum, a pathogen of stored broccoli

    Microsoft Academic Search

    Julien Mercier; Joseph Makhlouf; Richard A. Martin

    Fusarium avenaceum was identified as a new pathogen of broccoli kept in long-term storage at low temperature and controlled atmosphere. The first sign of the disease was growth of a white fluffy mycelium partly covering the inflorescence. Although disease development was very slow at 5OC, breaking the cold chain did cause outbreaks of infection in apparently healthy broccoli. Broccoli stored

  7. Effect of root exudates of different resistant varieties of cucumber on fusarium wilt and preliminary studies on their resistance mechanism

    Microsoft Academic Search

    Benli Huang; Yundong Xu; Ye Wu; Shunqi Zhang; Xuehao Chen

    2008-01-01

    This study investigated the effect of root exudates of cucumber varieties, Jinyan 4 (susceptible variety), Jinchun 4 (resistant\\u000a variety) and Yinnan Black seed squash on fusarium wilt. The results showed that fusarium wilt occurrence of plants treated\\u000a with the root exudate of Jinyan 4 was earlier. The infection rate was significantly higher 15 days after inoculation, but\\u000a similar to the

  8. Verticillium Wilt in Potato: Host-Pathogen Interactions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Verticillium wilt (VW) is a widespread disease that causes consistent yield losses in many potato growing regions worldwide. In the U.S., it is mainly caused by the soil-borne fungal pathogen Verticillium dahliae. Microsclerotia can survive in the soil for many years. When they germinate and infec...

  9. Thyme essential oil as a defense inducer of tomato against gray mold and Fusarium wilt.

    PubMed

    Ben-Jabeur, Maissa; Ghabri, Emna; Myriam, Machraoui; Hamada, Walid

    2015-09-01

    The potential of thyme essential oil in controlling gray mold and Fusarium wilt and inducing systemic acquired resistance in tomato seedlings and tomato grown in hydroponic system was evaluated. Thyme oil highly reduced 64% of Botrytis cinerea colonization on pretreated detached leaves compared to untreated control. Also, it played a significant decrease in Fusarium wilt severity especially at7 days post treatment when it was reduced to 30.76%. To explore the plant pathways triggered in response to thyme oil, phenolic compounds accumulation and peroxidase activity was investigated. Plant response was observed either after foliar spray or root feeding in hydroponics which was mostly attributed to peroxidases accumulation rather than phenolic compounds accumulation, and thyme oil seems to be more effective when applied to the roots. PMID:26002413

  10. Prospects for integrated control of ‘bayoud’ (Fusarium wilt of the date palm) in Algerian plantations

    Microsoft Academic Search

    R. A. Brac de la Perrière; H. Amir; N. Bounaga

    1995-01-01

    Fusarium wilt of date palm, also known as bayoud, is a major disease in North Africa. In Algeria, the wide range of agro-systems, soil types, genetic diversity of palm plantations and the extent of contamination in diseased areas suggest the need for an integrated? plantation-specific control strategy. In areas with disease-free plantations, the regulations on movement of planting material and

  11. [Effects of nitrogen application rate on faba bean fusarium wilt and rhizospheric microbial metabolic functional diversity].

    PubMed

    Dong, Yan; Yang, Zhi-xian; Dong, Kun; Tang, Li; Zheng, Yi; Hu, Guo-bin

    2013-04-01

    A field plot experiment was conducted to study the effects of different nitrogen (N) application rates on the microbial functional diversity in faba bean rhizosphere and the relationships between the microbial functional diversity and the occurrence of faba bean fusarium wilt. Four nitrogen application rates were installed, i. e. , N0(0 kg hm-2 , N1 (56. 25 kg hm-2) , N2(112. 5 kg hm-2), and N3 (168.75 kg hm-2), and Biolog microbial analysis system was applied to study the damage of faba bean fusarium wilt and the rhizospheric microbial metabolic functional diversity. Applying N (N1 N2, and N3) decreased the disease index of faba bean fusarium wilt and the quantity of Fusarium oxysporum significantly, and increased the quantities of bacteria and actinomyces and the ratios of bacteria/fungi and actinomyces/fungi significantly, with the peak values of bacteria and actinomyces, bacteria/fungi, and actinomyces/fungi, and the lowest disease index and F. oxysporum density in N2. As compared with N0, applying N increased the AWCD value significantly, but the effects of different N application rates on the ability of rhizospheric microbes in utilizing six types of carbon sources had definite differences. Under the application of N, the utilization rates of carbohydrates, carboxylic acids, and amino acids by the rhizospheric microbes were higher. Principal component analysis demonstrated that applying N changed the rhizospheric microbial community composition obviously, and the carbohydrates, carboxylic acids, and amino acids were the sensitive carbon sources differentiating the changes of the microbial community induced by N application. Applying N inhibited the utilization of carbohydrates and carboxylic acids but improved the utilization of amino acids and phenolic acids by the rhizospheric microbes, which could be one of the main reasons of applying N being able to reduce the harm of faba bean fusarium wilt. It was suggested that rationally applying N could increase the quantities of rhizospheric bacteria and actinomyces, alter the microbial metabolic function, and decrease F. oxysporum density, being an effective measure to control the occurrence of faba bean fusarium wilt. PMID:23898671

  12. Inoculum Densities of Fusarium oxysporum f. sp. vasinfectum and Meloidogyne incognita in Relation to the Development of Fusarium Wilt and the Phenology of Cotton Plants (Gossypium hirsutum).

    PubMed

    Devay, J E; Gutierrez, A P; Pullman, G S; Wakeman, R J; Garber, R H; Jeffers, D P; Smith, S N; Goodell, P B; Roberts, P A

    1997-03-01

    ABSTRACT Development of Fusarium wilt in upland cotton (Gossypium hirsutum) usually requires infections of plants by both Meloidogyne incognita and Fusarium oxysporum f. sp. vasinfectum. In this study, the soil densities of M. incognita and F. oxysporum f. sp. vasinfectum and the incidence of Fusarium wilt in three field sites were determined in 1982-1984. Multiple regression analysis of percent incidence of Fusarium wilt symptoms on population densities of M. incognita and F. oxysporum f. sp. vasinfectum yielded a significant fit (R (2) = 0.64) only on F. oxysporum f. sp. vasinfectum. Significant t-values for slope were also obtained for the interaction of M. incognita and F. oxysporum f. sp. vasinfectum, but densities of M. incognita and F. oxysporum f. sp. vasinfectum were also related on a log(10) scale. The physiological time of appearance of first foliar symptoms of Fusarium wilt, based on a degree-days threshold of 11.9 degrees C (53.5 degrees F), was used as a basis for determining disease progress curves and the phenology of cotton plant growth and development. Effects of Fusarium wilt on plant height and boll set were determined in three successive years. Increases in both of these plant characteristics decreased or stopped before foliar symptoms were apparent. Seed cotton yields of plant cohorts that developed foliar wilt symptoms early in the season (before 2,000 F degree-days) were variable but not much different in these years. This contrasted with cohorts of plants that first showed foliar symptoms late in the season (after 2,400 F degree-days) and cohorts of plants that showed no foliar symptoms of wilt. Regression analyses for 1982-1984 indicated moderate to weak correlations (r = 0.16-0.74) of the time of appearance of the first foliar symptoms and seed cotton yields. PMID:18945178

  13. [Faba bean fusarium wilt (Fusarium oxysporum )control and its mechanism in different wheat varieties and faba bean intercropping system].

    PubMed

    Dong, Yan; Dong, Kun; Zheng, Yi; Tang, Li; Yang, Zhi-Xian

    2014-07-01

    Field experiment and hydroponic culture were conducted to investigate effects of three wheat varieties (Yunmai 42, Yunmai 47 and Mianyang 29) and faba bean intercropping on the shoot biomass, disease index of fusarium wilt, functional diversity of microbial community and the amount of Fusarium oxysporum in rhizosphere of faba bean. Contents and components of the soluble sugars, free amino acids and organic acids in the root exudates were also examined. Results showed that, compared with monocropped faba bean, shoot biomass of faba bean significantly increased by 16.6% and 13.4%, disease index of faba bean fusarium wilt significantly decreased by 47.6% and 23.3% as intercropped with Yunmai 42 and Yunmai 47, but no significant differences of both shoot biomass and disease index were found as intercropped with Mianyang 29. Compared with monocropped faba bean, the average well color development (AWCD value) and total utilization ability of carbon sources of faba bean significantly increased, the amount of Fusarium oxysporum of faba bean rhizosphere significantly decreased, and the microbial community structures of faba bean rhizosphere changed as intercropped with YM42 and YM47, while no significant effects as intercropped with MY29. Total contents of soluble sugar, free amino acids and organic acids in root exudates were in the trend of MY29>YM47>YM42. Contents of serine, glutamic, glycine, valine, methionine, phenylalanine, lysine in root exudates of MY29 were significantly higher than that in YM42 and YM47. The arginine was detected only in the root exudates of YM42 and YM47, and leucine was detected only in the root exudates of MY29. Six organic acids of tartaric acid, malic acid, citric acid, succinic acid, fumaric acid, t-aconitic acid were detected in root exudates of MY29 and YM47, and four organic acids of tartaric acid, malic acid, citric acid, fumaric acid were detected in root exudates of YM42. Malic acid content in root exudates of YM47 and MY29 was significantly higher than that of YM42. In conclusion, intercropping influenced the microbial activity and substrate utilization of soil microorganisms, altered the microbial community diversity in rhizosphere of faba bean, reduced the amount of F. oxysporum and disease index of faba bean fusarium wilt, and promoted faba bean growth. Effects of intercropping on disease control were influenced by the intercropped wheat variety, suggesting that the differences of root exudates of wheat were important factors that affected soil-borne diseases control in intercropping. PMID:25345048

  14. The rhizosphere microbial community in a multiple parallel mineralization system suppresses the pathogenic fungus Fusarium oxysporum.

    PubMed

    Fujiwara, Kazuki; Iida, Yuichiro; Iwai, Takashi; Aoyama, Chihiro; Inukai, Ryuya; Ando, Akinori; Ogawa, Jun; Ohnishi, Jun; Terami, Fumihiro; Takano, Masao; Shinohara, Makoto

    2013-12-01

    The rhizosphere microbial community in a hydroponics system with multiple parallel mineralization (MPM) can potentially suppress root-borne diseases. This study focused on revealing the biological nature of the suppression against Fusarium wilt disease, which is caused by the fungus Fusarium oxysporum, and describing the factors that may influence the fungal pathogen in the MPM system. We demonstrated that the rhizosphere microbiota that developed in the MPM system could suppress Fusarium wilt disease under in vitro and greenhouse conditions. The microbiological characteristics of the MPM system were able to control the population dynamics of F. oxysporum, but did not eradicate the fungal pathogen. The roles of the microbiological agents underlying the disease suppression and the magnitude of the disease suppression in the MPM system appear to depend on the microbial density. F. oxysporum that survived in the MPM system formed chlamydospores when exposed to the rhizosphere microbiota. These results suggest that the microbiota suppresses proliferation of F. oxysporum by controlling the pathogen's morphogenesis and by developing an ecosystem that permits coexistence with F. oxysporum. PMID:24311557

  15. The rhizosphere microbial community in a multiple parallel mineralization system suppresses the pathogenic fungus Fusarium oxysporum

    PubMed Central

    Fujiwara, Kazuki; Iida, Yuichiro; Iwai, Takashi; Aoyama, Chihiro; Inukai, Ryuya; Ando, Akinori; Ogawa, Jun; Ohnishi, Jun; Terami, Fumihiro; Takano, Masao; Shinohara, Makoto

    2013-01-01

    The rhizosphere microbial community in a hydroponics system with multiple parallel mineralization (MPM) can potentially suppress root-borne diseases. This study focused on revealing the biological nature of the suppression against Fusarium wilt disease, which is caused by the fungus Fusarium oxysporum, and describing the factors that may influence the fungal pathogen in the MPM system. We demonstrated that the rhizosphere microbiota that developed in the MPM system could suppress Fusarium wilt disease under in vitro and greenhouse conditions. The microbiological characteristics of the MPM system were able to control the population dynamics of F. oxysporum, but did not eradicate the fungal pathogen. The roles of the microbiological agents underlying the disease suppression and the magnitude of the disease suppression in the MPM system appear to depend on the microbial density. F. oxysporum that survived in the MPM system formed chlamydospores when exposed to the rhizosphere microbiota. These results suggest that the microbiota suppresses proliferation of F. oxysporum by controlling the pathogen's morphogenesis and by developing an ecosystem that permits coexistence with F. oxysporum. PMID:24311557

  16. Comparative genomics reveals mobile pathogenicity chromosomes in Fusarium

    PubMed Central

    Ma, Li-Jun; van der Does, H. Charlotte; Borkovich, Katherine A.; Coleman, Jeffrey J.; Daboussi, Marie-Josée; Di Pietro, Antonio; Dufresne, Marie; Freitag, Michael; Grabherr, Manfred; Henrissat, Bernard; Houterman, Petra M.; Kang, Seogchan; Shim, Won-Bo; Woloshuk, Charles; Xie, Xiaohui; Xu, Jin-Rong; Antoniw, John; Baker, Scott E.; Bluhm, Burton H.; Breakspear, Andrew; Brown, Daren W.; Butchko, Robert A. E.; Chapman, Sinead; Coulson, Richard; Coutinho, Pedro M.; Danchin, Etienne G. J.; Diener, Andrew; Gale, Liane R.; Gardiner, Donald M.; Goff, Stephen; Hammond-Kosack, Kim E.; Hilburn, Karen; Hua-Van, Aurélie; Jonkers, Wilfried; Kazan, Kemal; Kodira, Chinnappa D.; Koehrsen, Michael; Kumar, Lokesh; Lee, Yong-Hwan; Li, Liande; Manners, John M.; Miranda-Saavedra, Diego; Mukherjee, Mala; Park, Gyungsoon; Park, Jongsun; Park, Sook-Young; Proctor, Robert H.; Regev, Aviv; Ruiz-Roldan, M. Carmen; Sain, Divya; Sakthikumar, Sharadha; Sykes, Sean; Schwartz, David C.; Turgeon, B. Gillian; Wapinski, Ilan; Yoder, Olen; Young, Sarah; Zeng, Qiandong; Zhou, Shiguo; Galagan, James; Cuomo, Christina A.; Kistler, H. Corby; Rep, Martijn

    2011-01-01

    Fusarium species are among the most important phytopathogenic and toxigenic fungi. To understand the molecular underpinnings of pathogenicity in the genus Fusarium, we compared the genomes of three phenotypically diverse species: Fusarium graminearum, Fusarium verticillioides and Fusarium oxysporum f. sp. lycopersici. Our analysis revealed lineage-specific (LS) genomic regions in F. oxysporum that include four entire chromosomes and account for more than one-quarter of the genome. LS regions are rich in transposons and genes with distinct evolutionary profiles but related to pathogenicity, indicative of horizontal acquisition. Experimentally, we demonstrate the transfer of two LS chromosomes between strains of F. oxysporum, converting a non-pathogenic strain into a pathogen. Transfer of LS chromosomes between otherwise genetically isolated strains explains the polyphyletic origin of host specificity and the emergence of new pathogenic lineages in F. oxysporum. These findings put the evolution of fungal pathogenicity into a new perspective. PMID:20237561

  17. Relation of Cotton Root Rot and Fusarium Wilt to the Acidity and Alkalinity of the Soil. 

    E-print Network

    Taubenhaus, J. J. (Jacob Joseph); Ezekiel, Walter N. (Walter Naphtali); Killough, D. T. (David Thornton)

    1928-01-01

    HOME RESEARCH: JESSIE WHITACRE Ph. D Chief MAMIE GRIMES, M. S., ~eztile and Clothing S~ecralrst 5. SUMNER. M. S., Nutrition Specialist - - - - - - - - . - - - **W T. CARTER B. S. Chief E. 'H. TEMPLI~; B S' Soil Sutvegor T. C. REITCH. B. s.. $oil... examined, and the acidity or alkalinity of the soil studied in relation to the pres- ence of cotton root rot and also of Fusarium wilt. Root rot was found in acid soils (pH 5.5-6.4) as well as in neutral (pH 6.5-7.4) and alkaline soils (pH 7.5...

  18. Progress in breeding for tolerance to Fusarium wilt (FOV) races 1 and 4 in the San Joaquin Valley (SJV) of California.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The vulnerability of cotton production in California to Fusarium wilt [Fusarium oxysporum f. sp. vasinfectum (FOV)] highlights the need for comprehensive research to protect the future of the cotton industry in the San Joaquin Valley (SJV). A recently identified problematic strain of Fusarium (race ...

  19. Identification of an Endophytic Antifungal Bacterial Strain Isolated from the Rubber Tree and Its Application in the Biological Control of Banana Fusarium Wilt

    PubMed Central

    Sun, Xuepiao; Zheng, Peng; Zhang, Jiaming

    2015-01-01

    Banana Fusarium wilt (also known as Panama disease) is one of the most disastrous plant diseases. Effective control methods are still under exploring. The endophytic bacterial strain ITBB B5-1 was isolated from the rubber tree, and identified as Serratia marcescens by morphological, biochemical, and phylogenetic analyses. This strain exhibited a high potential for biological control against the banana Fusarium disease. Visual agar plate assay showed that ITBB B5-1 restricted the mycelial growth of the pathogenic fungus Fusarium oxysporum f. sp. cubense race 4 (FOC4). Microscopic observation revealed that the cell wall of the FOC4 mycelium close to the co-cultured bacterium was partially decomposed, and the conidial formation was prohibited. The inhibition ratio of the culture fluid of ITBB B5-1 against the pathogenic fungus was 95.4% as estimated by tip culture assay. Chitinase and glucanase activity was detected in the culture fluid, and the highest activity was obtained at Day 2 and Day 3 of incubation for chitinase and glucanase, respectively. The filtrated cell-free culture fluid degraded the cell wall of FOC4 mycelium. These results indicated that chitinase and glucanase were involved in the antifungal mechanism of ITBB B5-1. The potted banana plants that were inoculated with ITBB B5-1 before infection with FOC4 showed 78.7% reduction in the disease severity index in the green house experiments. In the field trials, ITBB B5-1 showed a control effect of approximately 70.0% against the disease. Therefore, the endophytic bacterial strain ITBB B5-1 could be applied in the biological control of banana Fusarium wilt. PMID:26133557

  20. Rhizosphere Inhibition of Cucumber Fusarium Wilt by Different Surfactin- excreting Strains of Bacillus subtilis

    PubMed Central

    Jia, Ke; Gao, Yu-Han; Huang, Xiao-Qin; Guo, Rong-Jun; Li, Shi-Dong

    2015-01-01

    Bacillus subtilis B006 strain effectively suppresses the cucumber fusarium wilt caused by Fusarium oxysporum f. sp. cucumerinum (Foc). The population dynamics of Foc, strain B006 and its surfactin over-producing mutant B841 and surfactin-deficient mutant B1020, in the rhizosphere were determined under greenhouse conditions to elucidate the importance of the lipopeptides excreted by these strains in suppressing Foc. Results showed that B. subtilis strain B006 effectively suppressed the disease in natural soil by 42.9%, five weeks after transplanting, whereas B841 and B1020 suppressed the disease by only 22.6% and 7.1%, respectively. Quantitative PCR assays showed that effective colonization of strain B006 in the rhizosphere suppressed Foc propagation by more than 10 times both in nursery substrate and in field-infected soil. Reduction of Foc population at the cucumber stems in a range of 0.96 log10 ng/g to 2.39 log10 ng/g was attained at the third and the fifth weeks of B006 treatment in nursery substrate. In field-infected soil, all three treatments with B. subtilis suppressed Foc infection, indicated by the reduction of Foc population at a range of 2.91 log10 ng/g to 3.36 log10 ng/g at the stem base, one week after transplanting. This study reveals that the suppression of fusarium wilt disease is affected by the effective colonization of the surfactin-producing B. subtilis strain in the rhizosphere. These results improved our understanding of the biocontrol mechanism of the B. subtilis strain B006 in the natural soil and facilitate its application as biocontrol agent in the field. PMID:26060433

  1. Rhizosphere Inhibition of Cucumber Fusarium Wilt by Different Surfactin- excreting Strains of Bacillus subtilis.

    PubMed

    Jia, Ke; Gao, Yu-Han; Huang, Xiao-Qin; Guo, Rong-Jun; Li, Shi-Dong

    2015-06-01

    Bacillus subtilis B006 strain effectively suppresses the cucumber fusarium wilt caused by Fusarium oxysporum f. sp. cucumerinum (Foc). The population dynamics of Foc, strain B006 and its surfactin over-producing mutant B841 and surfactin-deficient mutant B1020, in the rhizosphere were determined under greenhouse conditions to elucidate the importance of the lipopeptides excreted by these strains in suppressing Foc. Results showed that B. subtilis strain B006 effectively suppressed the disease in natural soil by 42.9%, five weeks after transplanting, whereas B841 and B1020 suppressed the disease by only 22.6% and 7.1%, respectively. Quantitative PCR assays showed that effective colonization of strain B006 in the rhizosphere suppressed Foc propagation by more than 10 times both in nursery substrate and in field-infected soil. Reduction of Foc population at the cucumber stems in a range of 0.96 log10 ng/g to 2.39 log10 ng/g was attained at the third and the fifth weeks of B006 treatment in nursery substrate. In field-infected soil, all three treatments with B. subtilis suppressed Foc infection, indicated by the reduction of Foc population at a range of 2.91 log10 ng/g to 3.36 log10 ng/g at the stem base, one week after transplanting. This study reveals that the suppression of fusarium wilt disease is affected by the effective colonization of the surfactin-producing B. subtilis strain in the rhizosphere. These results improved our understanding of the biocontrol mechanism of the B. subtilis strain B006 in the natural soil and facilitate its application as biocontrol agent in the field. PMID:26060433

  2. Class V chitin synthase determines pathogenesis in the vascular wilt fungus Fusarium oxysporum and mediates resistance to plant defence compounds.

    PubMed

    Madrid, Martan P; Di Pietro, Antonio; Roncero, M Isabel G

    2003-01-01

    Chitin, a beta-1,4-linked polysaccharide of N-acetylglucosamine, is a major structural component of fungal cell walls. Fungi have multiple classes of chitin synthases that catalyse N-acetylglucosamine polymerization. Here, we demonstrate the requirement for a class V chitin synthase during host infection by the vascular wilt pathogen Fusarium oxysporum. The chsV gene was identified in an insertional mutagenesis screen for pathogenicity mutants. ChsV has a putative myosin motor and a chitin synthase domain characteristic of class V chitin synthases. The chsV insertional mutant and a gene replacement mutant of F. oxysporum display morphological abnormalities such as hyphal swellings that are indicative of alterations in cell wall structure and can be partially restored by osmotic stabilizer. The mutants are unable to infect and colonize tomato plants or to grow invasively on tomato fruit tissue. They are also hypersensitive to plant antimicrobial defence compounds such as the tomato phytoanticipin alpha-tomatine or H2O2. Reintroduction of a functional chsV copy into the mutant restored the growth phenotype of the wild-type strain. These data suggest that F. oxysporum requires a specific class V chitin synthase for pathogenesis, most probably to protect itself against plant defence mechanisms. PMID:12492869

  3. BREEDING FOR FUSARIUM WILT RACE 4 RESISTANCE IN COTTON UNDER FIELD AND GREENHOUSE CONDITIONS.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium oxysporum f. sp. vasinfectum (FOV) Atk. Sny & Hans represents a continuing threat to cotton production in the U.S. that warrants attention in plant breeding efforts. Several troubling developments concerning this pathogen (e.g., newly-recognized Australian FOV races and race 4 FOV identific...

  4. Proteomics of Fusarium oxysporum race 1 and race 4 reveals enzymes involved in carbohydrate metabolism and ion transport that might play important roles in banana Fusarium wilt.

    PubMed

    Sun, Yong; Yi, Xiaoping; Peng, Ming; Zeng, Huicai; Wang, Dan; Li, Bo; Tong, Zheng; Chang, Lili; Jin, Xiang; Wang, Xuchu

    2014-01-01

    Banana Fusarium wilt is a soil-spread fungal disease caused by Fusarium oxysporum. In China, the main virulence fungi in banana are F. oxysporum race 1 (F1, weak virulence) and race 4 (F4, strong virulence). To date, no proteomic analyses have compared the two races, but the difference in virulence between F1 and F4 might result from their differentially expressed proteins. Here we report the first comparative proteomics of F1 and F4 cultured under various conditions, and finally identify 99 protein species, which represent 59 unique proteins. These proteins are mainly involved in carbohydrate metabolism, post-translational modification, energy production, and inorganic ion transport. Bioinformatics analysis indicated that among the 46 proteins identified from F4 were several enzymes that might be important for virulence. Reverse transcription PCR analysis of the genes for 15 of the 56 proteins revealed that their transcriptional patterns were similar to their protein expression patterns. Taken together, these data suggest that proteins involved in carbohydrate metabolism and ion transport may be important in the pathogenesis of banana Fusarium wilt. Some enzymes such as catalase-peroxidase, galactosidase and chitinase might contribute to the strong virulence of F4. Overexpression or knockout of the genes for the F4-specific proteins will help us to further understand the molecular mechanism of Fusarium-induced banana wilt. PMID:25460190

  5. Discovery of a new source of resistance to Fusarium oxysporum, cause of Fusarium wilt in Allium fistulosum, located on chromosome 2 of Allium cepa Aggregatum group.

    PubMed

    Vu, Hoa Q; El-Sayed, Magdi A; Ito, Shin-Ichi; Yamauchi, Naoki; Shigyo, Masayoshi

    2012-11-01

    This study was carried out to evaluate the antifungal effect of Allium cepa Aggregatum group (shallot) metabolites on Fusarium oxysporum and to determine the shallot chromosome(s) related to Fusarium wilt resistance using a complete set of eight Allium fistulosum - shallot monosomic addition lines. The antifungal effects of hexane, butanol, and water extraction fractions from bulbs of shallot on 35 isolates of F. oxysporum were examined using the disc diffusion method. Only hexane and butanol fractions showed high antifungal activity. Shallot showed no symptom of disease after inoculation with F. oxysporum f. sp. cepae. The phenolic content of the roots and the saponin content of root exudates of inoculated shallot increased to much higher levels than those of the control at 3 days after inoculation. Application of freeze-dried shallot root exudates to seeds of A. fistulosum soaked in a spore suspension of F. oxysporum resulted in protection of seedlings against infection. Among eight monosomic addition lines and A. fistulosum, FF+2A showed the highest resistance to Fusarium wilt. This monosomic addition line also showed a specific saponin band derived from shallot on the thin layer chromatography profile of saponins in the eight monosomic addition lines. The chromosome 2A of shallot might possess some of the genes related to Fusarium wilt resistance. PMID:23199574

  6. Proteomics of Fusarium oxysporum Race 1 and Race 4 Reveals Enzymes Involved in Carbohydrate Metabolism and Ion Transport That Might Play Important Roles in Banana Fusarium Wilt

    PubMed Central

    Peng, Ming; Zeng, Huicai; Wang, Dan; Li, Bo; Tong, Zheng; Chang, Lili; Jin, Xiang; Wang, Xuchu

    2014-01-01

    Banana Fusarium wilt is a soil–spread fungal disease caused by Fusarium oxysporum. In China, the main virulence fungi in banana are F. oxysporum race 1 (F1, weak virulence) and race 4 (F4, strong virulence). To date, no proteomic analyses have compared the two races, but the difference in virulence between F1 and F4 might result from their differentially expressed proteins. Here we report the first comparative proteomics of F1 and F4 cultured under various conditions, and finally identify 99 protein species, which represent 59 unique proteins. These proteins are mainly involved in carbohydrate metabolism, post-translational modification, energy production, and inorganic ion transport. Bioinformatics analysis indicated that among the 46 proteins identified from F4 were several enzymes that might be important for virulence. Reverse transcription PCR analysis of the genes for 15 of the 56 proteins revealed that their transcriptional patterns were similar to their protein expression patterns. Taken together, these data suggest that proteins involved in carbohydrate metabolism and ion transport may be important in the pathogenesis of banana Fusarium wilt. Some enzymes such as catalase-peroxidase, galactosidase and chitinase might contribute to the strong virulence of F4. Overexpression or knockout of the genes for the F4-specific proteins will help us to further understand the molecular mechanism of Fusarium-induced banana wilt. PMID:25460190

  7. Verticillium comparative genomics yields insights into niche adaptation by plant vascular wilt pathogens.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The vascular wilt fungi Verticillium dahliae and V. albo-atrum infect over 200 plant species, causing billions of dollars in annual losses. The characteristic vascular wilt symptoms are a result of colonization and proliferation of the pathogens in the xylem vessels. To gain insights into the mechan...

  8. Comparative genomics yields insights into niche adaptation of plant vascular wilt pathogens.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The vascular wilt fungi Verticillium dahliae and V. albo-atrum infect over 200 plant species, causing billions of dollars in annual crop losses. The characteristic wilt symptoms are a result of colonization and proliferation of the pathogens in the xylem vessels, which undergo fluctuations in osmola...

  9. Monitoring of pathogenic and non?pathogenic Fusarium oxysporum strains during tomato plant infection

    PubMed Central

    Validov, Shamil Z.; Kamilova, Faina D.; Lugtenberg, Ben J. J.

    2011-01-01

    Summary Monitoring of pathogenic strains of Fusarium oxysporum (Fox), which cause wilt and rots on agricultural and ornamental plants, is important for predicting disease outbreaks. Since both pathogenic and non?pathogenic strains of Fox are ubiquitous and are able to colonize plant roots, detection of Fox DNA in plant material is not the ultimate proof of an ongoing infection which would cause damage to the plant. We followed the colonization of tomato plants by strains Fox f. sp. radicis?lycopersici ZUM2407 (a tomato foot and root rot pathogen), Fox f. sp. radicis?cucumerinum V03?2g (a cucumber root rot pathogen) and Fox Fo47 (a well?known non?pathogenic biocontrol strain). We determined fungal DNA concentrations in tomato plantlets by quantitative PCR (qPCR) with primers complementary to the intergenic spacer region (IGS) of these three Fox strains. Two weeks after inoculation of tomato seedlings with these Fox strains, the DNA concentration of Forl ZUM2407 was five times higher than that of the non?compatible pathogen Forc V03?2g and 10 times higher than that of Fo47. In 3?week?old plantlets the concentration of Forl ZUM2407 DNA was at least 10 times higher than those of the other strains. The fungal DNA concentration, as determined by qPCR, appeared to be in good agreement with data of the score of visible symptoms of tomato foot and root rot obtained 3 weeks after inoculation of tomato with Forl ZUM2407. Our results show that targeting of the multicopy ribosomal operon results in a highly sensitive qPCR reaction for the detection of Fox DNA. Since formae speciales of Fox cannot be distinguished by comparison of ribosomal operons, detection of Fox DNA is not evidence of plant infection by a compatible pathogen. Nevertheless, the observed difference in levels of plant colonization between pathogenic and non?pathogenic strains strongly suggests that a concentration of Fox DNA in plant material above the threshold level of 0.005% is due to proliferation of pathogenic Fox. PMID:21255375

  10. Monitoring of pathogenic and non-pathogenic Fusarium oxysporum strains during tomato plant infection.

    PubMed

    Validov, Shamil Z; Kamilova, Faina D; Lugtenberg, Ben J J

    2011-01-01

    Monitoring of pathogenic strains of Fusarium oxysporum (Fox), which cause wilt and rots on agricultural and ornamental plants, is important for predicting disease outbreaks. Since both pathogenic and non-pathogenic strains of Fox are ubiquitous and are able to colonize plant roots, detection of Fox DNA in plant material is not the ultimate proof of an ongoing infection which would cause damage to the plant. We followed the colonization of tomato plants by strains Fox f. sp. radicis-lycopersici ZUM2407 (a tomato foot and root rot pathogen), Fox f. sp. radiciscucumerinum V03-2g (a cucumber root rot pathogen) and Fox Fo47 (a well-known non-pathogenic biocontrol strain). We determined fungal DNA concentrations in tomato plantlets by quantitative PCR (qPCR) with primers complementary to the intergenic spacer region (IGS) of these three Fox strains. Two weeks after inoculation of tomato seedlings with these Fox strains, the DNA concentration of Forl ZUM2407 was five times higher than that of the non-compatible pathogen Forc V03-2g and 10 times higher than that of Fo47. In 3-week-old plantlets the concentration of Forl ZUM2407 DNA was at least 10 times higher than those of the other strains. The fungal DNA concentration, as determined by qPCR, appeared to be in good agreement with data of the score of visible symptoms of tomato foot and root rot obtained 3 weeks after inoculation of tomato with Forl ZUM2407. Our results show that targeting of the multicopy ribosomal operon results in a highly sensitive qPCR reaction for the detection of Fox DNA. Since formae speciales of Fox cannot be distinguished by comparison of ribosomal operons, detection of Fox DNA is not evidence of plant infection by a compatible pathogen. Nevertheless, the observed difference in levels of plant colonization between pathogenic and non-pathogenic strains strongly suggests that a concentration of Fox DNA in plant material above the threshold level of 0.005% is due to proliferation of pathogenic Fox. PMID:21255375

  11. Studies on the management of root-knot nematode, Meloidogyne incognita-wilt fungus, Fusarium oxysporum disease complex of green gram, Vigna radiata cv ML-1108

    PubMed Central

    Haseeb, Akhtar; Sharma, Anita; Shukla, Prabhat Kuma

    2005-01-01

    Studies were conducted under pot conditions to determine the comparative efficacy of carbofuran at 1 mg a.i./kg soil, bavistin at 1 mg a.i./kg soil, neem (Azadirachta indica) seed powder at 50 mg/kg soil, green mould (Trichoderma harzianum) at 50.0 ml/kg soil, rhizobacteria (Pseudomonas fluorescens) at 50.0 ml/kg soil against root-knot nematode, Meloidogyne incognita–wilt fungus, Fusarium oxysporum disease complex on green gram, Vigna radiata cv ML-1108. All the treatments significantly improved the growth of the plants as compared to untreated inoculated plants. Analysis of data showed that carbofuran and A. indica seed powder increased plant growth and yield significantly more in comparison to bavistin and P. fluorescens. Carbofuran was highly effective against nematode, bavistin against fungus, A. indica seed powder against both the pathogens and both the bioagents were moderately effective against both the pathogens. PMID:16052706

  12. Studies on the management of root-knot nematode, Meloidogyne incognita-wilt fungus, Fusarium oxysporum disease complex of green gram, Vigna radiata cv ML-1108.

    PubMed

    Haseeb, Akhtar; Sharma, Anita; Shukla, Prabhat Kumar

    2005-08-01

    Studies were conducted under pot conditions to determine the comparative efficacy of carbofuran at 1 mg a.i./kg soil, bavistin at 1 mg a.i./kg soil, neem (Azadirachta indica) seed powder at 50 mg/kg soil, green mould (Trichoderma harzianum) at 50.0 ml/kg soil, rhizobacteria (Pseudomonas fluorescens) at 50.0 ml/kg soil against root-knot nematode, Meloidogyne incognita-wilt fungus, Fusarium oxysporum disease complex on green gram, Vigna radiata cv ML-1108. All the treatments significantly improved the growth of the plants as compared to untreated inoculated plants. Analysis of data showed that carbofuran and A. indica seed powder increased plant growth and yield significantly more in comparison to bavistin and P. fluorescens. Carbofuran was highly effective against nematode, bavistin against fungus, A. indica seed powder against both the pathogens and both the bioagents were moderately effective against both the pathogens. PMID:16052706

  13. Plant growth-promoting rhizobacteria strain Bacillus amyloliquefaciens NJN-6-enriched bio-organic fertilizer suppressed Fusarium wilt and promoted the growth of banana plants.

    PubMed

    Yuan, Jun; Ruan, Yunze; Wang, Beibei; Zhang, Jian; Waseem, Raza; Huang, Qiwei; Shen, Qirong

    2013-04-24

    Bacillus amyloliquefaciens strain NJN-6 is an important plant growth-promoting rhizobacteria (PGPR) which can produce secondary metabolites antagonistic to several soil-borne pathogens. In this study, the ability of a bio-organic fertilizer (BIO) containing NJN-6 strain to promote the growth and suppress Fusarium wilt of banana plants was evaluated in a pot experiment. The results showed that the application of BIO significantly decreased the incidence of Fusarium wilt and promoted the growth of banana plants compared to that for the organic fertilizer (OF). To determine the beneficial mechanism of the strain, the colonization of NJN-6 strain on banana roots was evaluated using scanning electron microscopy (SEM). The plant growth-promoting hormones indole-3-acetic acid (IAA) and gibberellin A3 (GA3), along with antifungal lipopeptides iturin A, were detected when the NJN-6 strain was incubated in both Landy medium with additional l-tryptophan and in root exudates of banana plants. In addition, some antifungal volatile organic compounds and iturin A were also detected in BIO. In summary, strain NJN-6 could colonize the roots of banana plants after the application of BIO and produced active compounds which were beneficial for the growth of banana plants. PMID:23541032

  14. Rapid and efficient estimation of pea resistance to the soil-borne pathogen Fusarium oxysporum by infrared imaging.

    PubMed

    Rispail, Nicolas; Rubiales, Diego

    2015-01-01

    Fusarium wilts are widespread diseases affecting most agricultural crops. In absence of efficient alternatives, sowing resistant cultivars is the preferred approach to control this disease. However, actual resistance sources are often overcome by new pathogenic races, forcing breeders to continuously search for novel resistance sources. Selection of resistant accessions, mainly based on the evaluation of symptoms at timely intervals, is highly time-consuming. Thus, we tested the potential of an infra-red imaging system in plant breeding to speed up this process. For this, we monitored the changes in surface leaf temperature upon infection by F. oxysporum f. sp. pisi in several pea accessions with contrasting response to Fusarium wilt under a controlled environment. Using a portable infra-red imaging system we detected a significant temperature increase of at least 0.5 °C after 10 days post-inoculation in the susceptible accessions, while the resistant accession temperature remained at control level. The increase in leaf temperature at 10 days post-inoculation was positively correlated with the AUDPC calculated over a 30 days period. Thus, this approach allowed the early discrimination between resistant and susceptible accessions. As such, applying infra-red imaging system in breeding for Fusarium wilt resistance would contribute to considerably shorten the process of selection of novel resistant sources. PMID:25671514

  15. Fusaric acid production and pathogenicity of Fusarium oxysporum f. sp. vasinfectum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In recent years, Fusarium wilt of cotton has gained increased importance with the emergence of extremely virulent strains of Fusarium oxysporum f. sp. vasinfectum. The recent discovery of new pathotypes not previously found in the U.S. is of particular concern to the cotton industry. In addition, a ...

  16. The xylem as battleground for plant hosts and vascular wilt pathogens

    PubMed Central

    Yadeta, Koste A.; J. Thomma, Bart P. H.

    2013-01-01

    Vascular wilts are among the most destructive plant diseases that occur in annual crops as well as in woody perennials. These diseases are generally caused by soil-borne bacteria, fungi, and oomycetes that infect through the roots and enter the water-conducting xylem vessels where they proliferate and obstruct the transportation of water and minerals. As a consequence, leaves wilt and die, which may lead to impairment of the whole plant and eventually to death of the plant. Cultural, chemical, and biological measures to control this group of plant pathogens are generally ineffective, and the most effective control strategy is the use of genetic resistance. Owing to the fact that vascular wilt pathogens live deep in the interior of their host plants, studies into the biology of vascular pathogens are complicated. However, to design novel strategies to combat vascular wilt diseases, understanding the (molecular) biology of vascular pathogens and the molecular mechanisms underlying plant defense against these pathogens is crucial. In this review, we discuss the current knowledge on interactions of vascular wilt pathogens with their host plants, with emphasis on host defense responses against this group of pathogens. PMID:23630534

  17. Fusarium wilt (Fusarium oxysporum f. sp. vasinfectum) genes expressed during infection of cotton (Gossypium hirsutum)dagger.

    PubMed

    McFadden, Helen G; Wilson, Iain W; Chapple, Robin M; Dowd, Caitriona

    2006-03-01

    SUMMARY We sought to identify Fusarium oxysporum f. sp. vasinfectum (Fov) genes that may be associated with pathogenicity. Initially we utilized microarray and Q-PCR technology to identify Fov genes expressed in root and hypocotyl tissues during a compatible infection of cotton. We identified 218 fungal clones representing 174 Fov non-redundant genes as expressed in planta. The majority of the expressed sequences were expressed in infected roots, with only six genes detected in hypocotyl tissue. The Fov genes identified were predominately of unknown function or associated with fungal growth and energy production. We then analysed the expression of the identified fungal genes in infected roots and in saprophytically grown mycelia and identified 11 genes preferentially expressed in plant tissue. A putative oxidoreductase gene (with homology to AtsC) was found to be highly preferentially expressed in planta. In Agrobacterium tumefaciens, AtsC is associated with virulence. Inoculation of a susceptible and a partially resistant cotton cultivar with either a pathogenic or a non-pathogenic isolate of Fov revealed that the expression of the Fov AtsC homologue was associated with pathogenicity and disease symptom formation. PMID:20507430

  18. Proteomic analysis of Fusarium oxysporum f. sp. cubense tropical race 4-inoculated response to Fusarium wilts in the banana root cells

    PubMed Central

    2013-01-01

    Background Fusarium wilt of banana is one of the most destructive diseases in the world. This disease has caused heavy losses in major banana production areas. Except for molecular breeding methods based on plant defense mechanisms, effective methods to control the disease are still lacking. Dynamic changes in defense mechanisms between susceptible, moderately resistant, and highly resistant banana and Fusarium oxysporum f. sp. cubense tropical race 4 (Foc4) at the protein level remain unknown. This research reports the proteomic profile of three banana cultivars in response to Foc4 and transcriptional levels correlated with their sequences for the design of disease control strategies by molecular breeding. Results Thirty-eight differentially expressed proteins were identified to function in cell metabolism. Most of these proteins were positively regulated after Foc4 inoculation. These differentially regulated proteins were found to have important functions in banana defense response. Functional categories implicated that these proteins were associated with pathogenesis-related (PR) response; isoflavonoid, flavonoid, and anthocyanin syntheses; cell wall strengthening; cell polarization; reactive oxygen species production and scavenging; jasmonic acid-, abscisic acid-, and auxin-mediated signaling conduction; molecular chaperones; energy; and primary metabolism. By comparing the protein profiles of resistant and susceptible banana cultivars, many proteins showed obvious distinction in their defense mechanism functions. PR proteins in susceptible ‘Brazil’ were mainly involved in defense. The proteins related to PR response, cell wall strengthening and antifungal compound synthesis in moderately resistant ‘Nongke No.1’ were mainly involved in defense. The proteins related to PR response, cell wall strengthening, and antifungal compound synthesis in highly resistant ‘Yueyoukang I’ were mainly involved in defense. 12 differentially regulated genes were selected to validate through quantitative real time PCR method. Quantitative RT-PCR analyses of these selected genes corroborate with their respective protein abundance after pathogen infection. Conclusions This report is the first to use proteomic profiling to study the molecular mechanism of banana roots infected with Foc4. The differentially regulated proteins involved in different defense pathways are likely associated with different resistant levels of the three banana cultivars. PMID:24070062

  19. Phylogeny and pathogenicity of Fusarium oxysporum isolates from cottonseed imported from Australia into California for dairy cattle feed.

    PubMed

    Liu, Jinggao; Bell, Alois A; Wheeler, Michael H; Stipanovic, Robert D; Puckhaber, Lorraine S

    2011-11-01

    A unique biotype of the Fusarium wilt pathogen, Fusarium oxysporum Schlecht. f.sp. vasinfectum (Atk) Sny. & Hans., found in Australia in 1993 is favored by neutral or alkaline heavy soils and does not require plant parasitic nematodes to cause disease. This makes it a threat to 4-6 million acres of USA Upland cotton ( Gossypium hirsutum L.) that is grown on heavy alkaline soil and currently is not affected by Fusarium wilt. In 2001-2002, several shiploads of live cottonseed were imported into California for dairy cattle feed. Thirteen F. oxysporum f.sp. vasinfectum isolates and four isolates of a Fusarium spp. that resembled F. oxysporum were isolated from the imported cottonseed. The isolates, designated by an AuSeed prefix, formed four vegetative compatibility groups (VCG) all of which were incompatible with tester isolates for 18 VCGs found in the USA. Isolate AuSeed14 was vegetatively compatible with the four reference isolates of Australian biotype VCG01111. Phylogenetic analyses based on EF-1?, PHO, BT, Mat1-1, and Mat1-2 gene sequences separated the 17 seed isolates into three lineages (race A, race 3, and Fusarium spp.) with AuSeed14 clustering into race 3 lineage or race A lineage depending on the genes analyzed. Indel analysis of the EF-1? gene sequences revealed a close evolutionary relationship among AuSeed14, Australian biotype reference isolates, and the four Fusarium spp. isolates. The Australian seed isolates and the four Australian biotype reference isolates caused disease with root-dip inoculation, but not with stem-puncture inoculation. Thus, they were a vascular incompetent pathotype. In contrast, USA race A lineage isolates readily colonized vascular tissue and formed a vascular competent pathotype when introduced directly into xylem vessels. The AuSeed14 isolate was as pathogenic as the Australian biotype, and it or related isolates could cause a severe Fusarium wilt problem in USA cotton fields if they become established. PMID:22004096

  20. CHARACTERIZATION OF A FUSARIUM VERTICILLIOIDES SEEDLING PATHOGENICITY FACTOR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As part of a larger research program focusing on the capacity of Fusarium verticillioides to infect and endophytically colonize corn, we have examined an apparent seedling pathogenicity factor produced by the fungus. Genetic analysis of field isolates indicated a single locus segregates for ability...

  1. Polyamine metabolism in flax in response to treatment with pathogenic and non–pathogenic Fusarium strains

    PubMed Central

    Wojtasik, Wioleta; Kulma, Anna; Namys?, Katarzyna; Preisner, Marta; Szopa, Jan

    2015-01-01

    Flax crop yield is limited by various environmental stress factors, but the largest crop losses worldwide are caused by Fusarium infection. Polyamines are one of the many plant metabolites possibly involved in the plant response to infection. However, in flax plants the polyamine composition, genes involved in polyamine synthesis, and in particular their regulation, were previously unknown. The aim of this study was to investigate the polyamine synthesis pathway in flax and its involvement in response to pathogen infection. It is well established that polyamines are essential for the growth and development of both plants and fungi, but their role in pathogen infection still remains unknown. In our study we correlated the expression of genes involved in polyamine metabolism with the polyamine levels in plant tissues and compared the results for flax seedlings treated with two pathogenic and one non-pathogenic strains of Fusarium. We observed an increase in the expression of genes participating in polyamine synthesis after fungal infection, and it was reflected in an increase of polyamine content in the plant tissues. The highest level of mRNA was characteristic for ornithine decarboxylase during infection with all tested, pathogenic and non-pathogenic, Fusarium strains and the arginine decarboxylase gene during infection with the pathogenic strain of Fusarium culmorum. The main polyamine identified in the flax seedlings was putrescine, and its level changed the most during infection. Moreover, the considerable increase in the contents of cell wall-bound polyamines compared to the levels of free and conjugated polyamines may indicate that their main role during pathogen infection lies in strengthening of the cell wall. In vitro experiments showed that the polyamines inhibit Fusarium growth, which suggests that they play an important role in plant defense mechanisms. Furthermore, changes in metabolism and content of polyamines indicate different defense mechanisms activated in flax in response to infection by pathogenic and non-pathogenic Fusarium strains. PMID:25972886

  2. Inheritance and QTL mapping of Fusarium wilt race 4 resistance in cotton.

    PubMed

    Ulloa, Mauricio; Hutmacher, Robert B; Roberts, Philip A; Wright, Steven D; Nichols, Robert L; Michael Davis, R

    2013-05-01

    Diseases such as Fusarium wilt [Fusarium oxysporum f.sp. vasinfectum (FOV) Atk. Sny & Hans] represent expanding threats to cotton production. Integrating disease resistance into high-yielding, high-fiber quality cotton (Gossypium spp.) cultivars is one of the most important objectives in cotton breeding programs worldwide. In this study, we conducted a comprehensive analysis of gene action in cotton governing FOV race 4 resistance by combining conventional inheritance and quantitative trait loci (QTL) mapping with molecular markers. A set of diverse cotton populations was generated from crosses encompassing multiple genetic backgrounds. FOV race 4 resistance was investigated using seven parents and their derived populations: three intraspecific (G. hirsutum × G. hirsutum L. and G. barbadense × G. barbadense L.) F1 and F2; five interspecific (G. hirsutum × G. barbadense) F1 and F2; and one RIL. Parents and populations were evaluated for disease severity index (DSI) of leaves, and vascular stem and root staining (VRS) in four greenhouse and two field experiments. Initially, a single resistance gene (Fov4) model was observed in F2 populations based on inheritance of phenotypes. This single Fov4 gene had a major dominant gene action and conferred resistance to FOV race 4 in Pima-S6. The Fov4 gene appears to be located near a genome region on chromosome 14 marked with a QTL Fov4-C14 1 , which made the biggest contribution to the FOV race 4 resistance of the generated F2 progeny. Additional genetic and QTL analyses also identified a set of 11 SSR markers that indicated the involvement of more than one gene and gene interactions across six linkage groups/chromosomes (3, 6, 8, 14, 17, and 25) in the inheritance of FOV race 4 resistance. QTLs detected with minor effects in these populations explained 5-19 % of the DSI or VRS variation. Identified SSR markers for the resistance QTLs with major and minor effects will facilitate for the first time marker-assisted selection for the introgression of FOV race 4 resistance into elite cultivars during the breeding process. PMID:23471458

  3. Fusarium graminearum: an pathogen of maize in Nepal, pathogenic variability and mycotoxins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium graminearum is an important pathogen of maize in hills of Nepal. It predominantly occurs on maize grown in cool and humid environment of high hills. The pathogen is also known to infect other cereal crops including wheat and rice causing important diseases. The incidence of ear rot is hi...

  4. The Brassicaceae-Specific EWR1 Gene Provides Resistance to Vascular Wilt Pathogens

    PubMed Central

    Yadeta, Koste A.; Valkenburg, Dirk-Jan; Hanemian, Mathieu; Marco, Yves; Thomma, Bart P. H. J.

    2014-01-01

    Soil-borne vascular wilt diseases caused by Verticillium spp. are among the most destructive diseases worldwide in a wide range of plant species. The most effective means of controlling Verticillium wilt diseases is the use of genetic resistance. We have previously reported the identification of four activation-tagged Arabidopsis mutants which showed enhanced resistance to Verticillium wilt. Among these, one mutant also showed enhanced resistance to Ralstonia solanacearum, a bacterial vascular wilt pathogen. Cloning of the activation tag revealed an insertion upstream of gene At3g13437, which we designated as EWR1 (for Enhancer of vascular Wilt Resistance 1) that encodes a putatively secreted protein of unknown function. The search for homologs of Arabidopsis EWR1 (AtEWR1) in public databases only identified homologs within the Brassicaceae family. We subsequently cloned the EWR1 homolog from Brassica oleracea (BoEWR1) and show that over-expression in Arabidopsis results in V. dahliae resistance. Moreover, over-expression of AtEWR1 and BoEWR1 in N. benthamiana, a member of the Solanaceae family, results in V. dahliae resistance, suggesting that EWR1 homologs can be used to engineer Verticillium wilt resistance in non-Brassicaceae crops as well. PMID:24505441

  5. The Brassicaceae-specific EWR1 gene provides resistance to vascular wilt pathogens.

    PubMed

    Yadeta, Koste A; Valkenburg, Dirk-Jan; Hanemian, Mathieu; Marco, Yves; Thomma, Bart P H J

    2014-01-01

    Soil-borne vascular wilt diseases caused by Verticillium spp. are among the most destructive diseases worldwide in a wide range of plant species. The most effective means of controlling Verticillium wilt diseases is the use of genetic resistance. We have previously reported the identification of four activation-tagged Arabidopsis mutants which showed enhanced resistance to Verticillium wilt. Among these, one mutant also showed enhanced resistance to Ralstonia solanacearum, a bacterial vascular wilt pathogen. Cloning of the activation tag revealed an insertion upstream of gene At3g13437, which we designated as EWR1 (for Enhancer of vascular Wilt Resistance 1) that encodes a putatively secreted protein of unknown function. The search for homologs of Arabidopsis EWR1 (AtEWR1) in public databases only identified homologs within the Brassicaceae family. We subsequently cloned the EWR1 homolog from Brassica oleracea (BoEWR1) and show that over-expression in Arabidopsis results in V. dahliae resistance. Moreover, over-expression of AtEWR1 and BoEWR1 in N. benthamiana, a member of the Solanaceae family, results in V. dahliae resistance, suggesting that EWR1 homologs can be used to engineer Verticillium wilt resistance in non-Brassicaceae crops as well. PMID:24505441

  6. A polyketide synthase gene and an aspartate kinase like gene are required for the biosynthesis of fusaric acid in Fusarium Oxysporum f. sp. Vasinfectum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A genetically unique strain of the Fusarium wilt pathogen was first recognized in wilted and dead Upland cotton seedlings in Australia in 1993. Since that time the disease spread rapidly despite stringent containment practices. The Australian biotype isolates of Fusarium oxysporum f. sp. vasinfec...

  7. A POLYKETIDE SYNTHASE GENE AND AN ASPARTATE KINASE LIKE GENE ARE REQUIRED FOR THE BIOSYNTHESIS OF FUSARIC ACID IN FUSARIUM OXYSPORUM F. SP. VASINFECTUM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A genetically unique strain of the Fusarium wilt pathogen was first recognized in wilted and dead Upland cotton seedlings in Australia in 1993. Since that time the disease spread rapidly despite stringent containment practices. The Australian biotype isolates of Fusarium oxysporum f. sp. vasinfec...

  8. Verticillium comparative genomics yields insights into niche adaptation by plant vascular wilt pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The vascular wilt fungi Verticillium dahliae and V. albo-atrum infect over 200 plant species worldwide, causing recurring crop losses estimated in the billions of dollars annually. Plant pathogenic Verticillium species are soilborne, and produce dormant structures that enable survival for years in ...

  9. Comparative genomics reveals mobile pathogenicity chromosomes in Fusarium

    SciTech Connect

    Ma, Li Jun; van der Does, H. C.; Borkovich, Katherine A.; Coleman, Jeffrey J.; Daboussi, Marie-Jose; Di Pietro, Antonio; Dufresne, Marie; Freitag, Michael; Grabherr, Manfred; Henrissat, Bernard; Houterman, Petra M.; Kang, Seogchan; Shim, Won-Bo; Wolochuk, Charles; Xie, Xiaohui; Xu, Jin Rong; Antoniw, John; Baker, Scott E.; Bluhm, Burton H.; Breakspear, Andrew; Brown, Daren W.; Butchko, Robert A.; Chapman, Sinead; Coulson, Richard; Coutinho, Pedro M.; Danchin, Etienne G.; Diener, Andrew; Gale, Liane R.; Gardiner, Donald; Goff, Steven; Hammond-Kossack, Kim; Hilburn, Karen; Hua-Van, Aurelie; Jonkers, Wilfried; Kazan, Kemal; Kodira, Chinnappa D.; Koehrsen, Michael; Kumar, Lokesh; Lee, Yong Hwan; Li, Liande; Manners, John M.; Miranda-Saavedra, Diego; Mukherjee, Mala; Park, Gyungsoon; Park, Jongsun; Park, Sook Young; Proctor, Robert H.; Regev, Aviv; Ruiz-Roldan, M. C.; Sain, Divya; Sakthikumar, Sharadha; Sykes, Sean; Schwartz, David C.; Turgeon, Barbara G.; Wapinski, Ilan; Yoder, Olen; Young, Sarah; Zeng, Qiandong; Zhou, Shiguo; Galagan, James; Cuomo, Christina A.; Kistler, H. Corby; Rep, Martijn

    2010-03-18

    Fusarium species are among the most important phytopathogenic and toxigenic fungi, having significant impact on crop production and animal health. Distinctively, members of the F. oxysporum species complex exhibit wide host range but discontinuously distributed host specificity, reflecting remarkable genetic adaptability. To understand the molecular underpinnings of diverse phenotypic traits and their evolution in Fusarium, we compared the genomes of three economically important and phylogenetically related, yet phenotypically diverse plant-pathogenic species, F. graminearum, F. verticillioides and F. oxysporum f. sp. lycopersici. Our analysis revealed greatly expanded lineage-specific (LS) genomic regions in F. oxysporum that include four entire chromosomes, accounting for more than one-quarter of the genome. LS regions are rich in transposons and genes with distinct evolutionary profiles but related to pathogenicity. Experimentally, we demonstrate for the first time the transfer of two LS chromosomes between strains of F. oxysporum, resulting in the conversion of a non-pathogenic strain into a pathogen. Transfer of LS chromosomes between otherwise genetically isolated strains explains the polyphyletic origin of host specificity and the emergence of new pathogenic lineages in the F. oxysporum species complex, putting the evolution of fungal pathogenicity into a new perspective.

  10. Biosynthesis of fusaric acid by Fusarium oxysporum f. sp. vasinfectum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A genetically unique biotype of the Fusarium wilt pathogen was first recognized in wilted and dead Upland cotton (Gossypium hirsutum) seedlings in Australia in 1993. Since that time, the disease has spread rapidly with losses greater than 90 percent in some Australian fields where it was first disc...

  11. Toxin-based in-vitro selection and its potential application to date palm for resistance to the bayoud Fusarium wilt

    Microsoft Academic Search

    Abdelbasset El Hadrami; Abdelmalek El Idrissi-Tourane; Majida El Hassni; Fouad Daayf; Ismaïl El Hadrami

    2005-01-01

    Date palm (Phoenix dactylifera L.) is qualified as a ‘tree’ of great ecological and socio-economical importance in desert oases. Unfortunately, it is being decimated, especially in Morocco and Algeria, by a fusariosis wilt called bayoud and caused by Fusarium oxysporum f. sp. albedinis (Fao). Controlling this disease requires the implementation of an integrated management program. Breeding for resistance is one

  12. The tomato I-3 gene: a novel gene for resistance to Fusarium wilt disease.

    PubMed

    Catanzariti, Ann-Maree; Lim, Ginny T T; Jones, David A

    2015-07-01

    Plant resistance proteins provide race-specific immunity through the recognition of pathogen effectors. The resistance genes I, I-2 and I-3 have been incorporated into cultivated tomato (Solanum lycopersicum) from wild tomato species to confer resistance against Fusarium oxysporum f. sp. lycopersici (Fol) races 1, 2 and 3, respectively. Although the Fol effectors corresponding to these resistance genes have all been identified, only the I-2 resistance gene has been isolated from tomato. To isolate the I-3 resistance gene, we employed a map-based cloning approach and used transgenic complementation to test candidate genes for resistance to Fol race 3. Here, we describe the fine mapping and sequencing of genes at the I-3 locus, which revealed a family of S-receptor-like kinase (SRLK) genes. Transgenic tomato lines were generated with three of these SRLK genes and one was found to confer Avr3-dependent resistance to Fol race 3, confirming it to be I-3. The finding that I-3 encodes an SRLK reveals a new pathway for Fol resistance and a new class of resistance genes, of which Pi-d2 from rice is also a member. The identification of I-3 also allows the investigation of the complex effector-resistance protein interaction involving Avr1-mediated suppression of I-2- and I-3-dependent resistance in tomato. PMID:25740416

  13. Insight into the molecular requirements for pathogenicity of Fusarium oxysporum f. sp. lycopersici through large-scale insertional mutagenesis

    PubMed Central

    Michielse, Caroline B; van Wijk, Ringo; Reijnen, Linda; Cornelissen, Ben JC; Rep, Martijn

    2009-01-01

    Background Fusarium oxysporum f. sp. lycopersici is the causal agent of vascular wilt disease in tomato. In order to gain more insight into the molecular processes in F. oxysporum necessary for pathogenesis and to uncover the genes involved, we used Agrobacterium-mediated insertional mutagenesis to generate 10,290 transformants and screened the transformants for loss or reduction of pathogenicity. Results This led to the identification of 106 pathogenicity mutants. Southern analysis revealed that the average T-DNA insertion is 1.4 and that 66% of the mutants carry a single T-DNA. Using TAIL-PCR, chromosomal T-DNA flanking regions were isolated and 111 potential pathogenicity genes were identified. Conclusions Functional categorization of the potential pathogenicity genes indicates that certain cellular processes, such as amino acid and lipid metabolism, cell wall remodeling, protein translocation and protein degradation, seem to be important for full pathogenicity of F. oxysporum. Several known pathogenicity genes were identified, such as those encoding chitin synthase V, developmental regulator FlbA and phosphomannose isomerase. In addition, complementation and gene knock-out experiments confirmed that a glycosylphosphatidylinositol-anchored protein, thought to be involved in cell wall integrity, a transcriptional regulator, a protein with unknown function and peroxisome biogenesis are required for full pathogenicity of F. oxysporum. PMID:19134172

  14. Phylogeny and pathogenicity of Fusarium spp. isolated from greenhouse melon soil in Liaoning Province.

    PubMed

    Zhao, Baixia; Yan, Jianfang; Zhang, Shuo; Liu, Xian; Gao, Zenggui

    2014-09-01

    Fungi of the Fusarium oxysporum are widely distributed around the world in all types of soils, and they are all anamorphic species. In order to investigate the relationships and differences among Fusarium spp., 25 Fusarium spp. were isolated from greenhouse melon soils in Liaoning Province, China. With these 25 strains, three positive control Fusarium strains were analyzed using universally primed PCR (UP-PCR). Seventy-three bands appeared after amplification using 6 primers, and 66 of these bands (90.4%) were polymorphic. All strains were clustered into eight groups, though 14 strains of F. oxysporum were clustered into a single group. We concluded that UP-PCR could reveal the genetic relationships and differences among Fusarium strains. Moreover, the UP-PCR results suggested that F. oxysporum is distinguishable from other Fusarium spp. Thus, UP-PCR is a useful method for Fusarium classification. The pathogenicity of 13 strains of F. oxysporum to muskmelon, cucumber and watermelon seedlings was studied by infecting the seedlings with a spore suspension after cutting the root. The results showed that the F. oxysporum strains were pathogenic to all three melon types, although the pathogenicity differed significantly among the 13 strains. In addition, all strains had the greatest pathogenicity toward watermelon. Since the factors affecting pathogenicity vary widely, they should be considered in future studies on Fusarium spp. The results of such studies may then yield an accurate description of the pathogenicity of Fusarium spp. PMID:25183948

  15. Phylogeny and pathogenicity of Fusarium spp. isolated from greenhouse melon soil in Liaoning Province

    PubMed Central

    Zhao, Baixia; Yan, Jianfang; Zhang, Shuo; Liu, Xian; Gao, Zenggui

    2013-01-01

    Fungi of the Fusarium oxysporum are widely distributed around the world in all types of soils, and they are all anamorphic species. In order to investigate the relationships and differences among Fusarium spp., 25 Fusarium spp. were isolated from greenhouse melon soils in Liaoning Province, China. With these 25 strains, three positive control Fusarium strains were analyzed using universally primed PCR (UP-PCR). Seventy-three bands appeared after amplification using 6 primers, and 66 of these bands (90.4%) were polymorphic. All strains were clustered into eight groups, though 14 strains of F. oxysporum were clustered into a single group. We concluded that UP-PCR could reveal the genetic relationships and differences among Fusarium strains. Moreover, the UP-PCR results suggested that F. oxysporum is distinguishable from other Fusarium spp. Thus, UP-PCR is a useful method for Fusarium classification. The pathogenicity of 13 strains of F. oxysporum to muskmelon, cucumber and watermelon seedlings was studied by infecting the seedlings with a spore suspension after cutting the root. The results showed that the F. oxysporum strains were pathogenic to all three melon types, although the pathogenicity differed significantly among the 13 strains. In addition, all strains had the greatest pathogenicity toward watermelon. Since the factors affecting pathogenicity vary widely, they should be considered in future studies on Fusarium spp. The results of such studies may then yield an accurate description of the pathogenicity of Fusarium spp. PMID:25183948

  16. Assessing the Cost of an Invasive Forest Pathogen: A Case Study with Oak Wilt

    NASA Astrophysics Data System (ADS)

    Haight, Robert G.; Homans, Frances R.; Horie, Tetsuya; Mehta, Shefali V.; Smith, David J.; Venette, Robert C.

    2011-03-01

    Economic assessment of damage caused by invasive alien species provides useful information to consider when determining whether management programs should be established, modified, or discontinued. We estimate the baseline economic damage from an invasive alien pathogen, Ceratocystis fagacearum, a fungus that causes oak wilt, which is a significant disease of oaks ( Quercus spp.) in the central United States. We focus on Anoka County, Minnesota, a 1,156 km2 mostly urban county in the Minneapolis-Saint Paul metropolitan region. We develop a landscape-level model of oak wilt spread that accounts for underground and overland pathogen transmission. We predict the economic damage of tree mortality from oak wilt spread in the absence of management during the period 2007-2016. Our metric of economic damage is removal cost, which is one component of the total economic loss from tree mortality. We estimate that Anoka County has 5.92 million oak trees and 885 active oak wilt pockets covering 5.47 km2 in 2007. The likelihood that landowners remove infected oaks varies by land use and ranges from 86% on developed land to 57% on forest land. Over the next decade, depending on the rates of oak wilt pocket establishment and expansion, 76-266 thousand trees will be infected with discounted removal cost of 18-60 million. Although our predictions of removal costs are substantial, they are lower bounds on the total economic loss from tree mortality because we do not estimate economic losses from reduced services and increased hazards. Our predictions suggest that there are significant economic benefits, in terms of damage reduction, from preventing new pocket establishment or slowing the radial growth of existing pockets.

  17. A study on the susceptibility of the model legume plant Medicago truncatula to the soil-borne pathogen Fusarium oxysporum

    Microsoft Academic Search

    Montserrat Ramírez-Suero; Anas Khanshour; Yves Martinez; Martina Rickauer

    2010-01-01

    Fusarium wilt is a soil-borne disease caused by formae specialis of Fusarium oxysporum on a large number of cultivated and wild plants. The susceptibility of the model legume plant Medicago truncatula to Fusarium oxysporum was studied by root-inoculating young plants in a miniaturised hydroponic culture. Among eight tested M. truncatula lines, all were susceptible to F. oxysporum f.sp. medicaginis, the

  18. A new bioorganic fertilizer can effectively control banana wilt by strong colonization with Bacillus subtilis N11

    Microsoft Academic Search

    Nan Zhang; Kai Wu; Xin He; Shu-qing Li; Zhen-hua Zhang; Biao Shen; Xing-ming Yang; Rui-fu Zhang; Qi-wei Huang; Qi-rong Shen

    2011-01-01

    Fusarium wilt is one of the most serious diseases caused by a soil-borne pathogen affecting banana production. The goal of\\u000a this study was to evaluate the capability of a novel bio-organic fertilizer (BIO2) that integrated the biocontrol agent Bacillus subtilis N11, and mature composts to control Fusarium wilt of banana in pot experiments. The results showed that the application of

  19. Stable integration and expression of wasabi defensin gene in “Egusi” melon ( Colocynthis citrullus L.) confers resistance to Fusarium wilt and Alternaria leaf spot

    Microsoft Academic Search

    Valentine Otang Ntui; Gunaratnam Thirukkumaran; Pejman Azadi; Raham Sher Khan; Ikuo Nakamura; Masahiro Mii

    2010-01-01

    Production of “Egusi” melon (Colocynthis citrullus L.) in West Africa is limited by fungal diseases, such as Alternaria leaf spot and Fusarium wilt. In order to engineer “Egusi”\\u000a resistant to these diseases, cotyledonary explants of two “Egusi” genotypes, ‘Ejagham’ and NHC1-130, were transformed with\\u000a Agrobacterium tumefaciens strain EHA101 harbouring wasabi defensin gene (isolated from Wasabia japonica L.) in a binary

  20. Adaptive Potential of Maritime Pine (Pinus pinaster) Populations to the Emerging Pitch Canker Pathogen, Fusarium circinatum

    PubMed Central

    Elvira-Recuenco, Margarita; Iturritxa, Eugenia; Majada, Juan; Alia, Ricardo; Raposo, Rosa

    2014-01-01

    There is a concern on how emerging pests and diseases will affect the distribution range and adaptability of their host species, especially due to different conditions derived from climate change and growing globalization. Fusarium circinatum, which causes pitch canker disease in Pinus species, is an exotic pathogen of recent introduction in Spain that threatens its maritime pine (P. pinaster) stands. To predict the impact this disease will have on the species, we examine host resistance traits and their genetic architecture. Resistance phenotyping was done in a clonal provenance/progeny trial, using three-year-old cuttings artificially inoculated with the pathogen and maintained under controlled environmental conditions. A total number of 670 ramets were assessed, distributed in 10 populations, with a total of 47 families, 2 to 5 half-sibs per family, and 3–7 ramets per clone. High genetic variation was found at the three hierarchical levels studied: population, family and clone, being both additive and non-additive effects important. Narrow-sense and broad-sense heritability estimates were relatively high, with respective values of 0.43–0.58 and 0.51–0.8, depending on the resistance traits measured (lesion length, lesion length rate, time to wilting, and survival). These values suggest the species' high capacity of evolutionary response to the F. circinatum pathogen. A population originated in Northern Spain was the most resistant, while another from Morocco was the most susceptible. The total number of plants that did not show lesion development or presented a small lesion (length<30 mm) was 224 out of 670, indicating a high proportion of resistant trees in the offspring within the analyzed populations. We found large differences among populations and considerable genetic variation within populations, which should allow, through natural or artificial selection, the successful adaptation of maritime pine to pitch canker disease. PMID:25500822

  1. Toxin-based in-vitro selection and its potential application to date palm for resistance to the bayoud Fusarium wilt.

    PubMed

    El Hadrami, Abdelbasset; El Idrissi-Tourane, Abdelmalek; El Hassni, Majida; Daayf, Fouad; El Hadrami, Ismaïl

    2005-08-01

    Date palm (Phoenix dactylifera L.) is qualified as a 'tree' of great ecological and socio-economical importance in desert oases. Unfortunately, it is being decimated, especially in Morocco and Algeria, by a fusariosis wilt called bayoud and caused by Fusarium oxysporum f. sp. albedinis (Fao). Controlling this disease requires the implementation of an integrated management program. Breeding for resistance is one of the most promising component strategies of this program. Few naturally resistant cultivars with a mediocre fruit quality (dates) are known. Conventional and non-conventional methods are under development and have to use the simplest and easiest methods to screen for resistant individuals. The use of pathogen toxins as selective agents at the tissue culture step might be a source of variability that can lead to the selection of individuals with suitable levels of resistance to the toxin and/or to the pathogen among the genetic material available. Foa produces toxins such as fusaric, succinic, 3-phenyl lactic acids and their derivatives, marasmins and peptidic toxins. These toxins can be used bulked or separately as selective agents. The aim of this contribution was to give a brief overview on toxins and their use as a mean to select resistant lines and to initiate a discussion about the potential use of this approach for the date palm-Foa pathosystem. This review does not pretend to be comprehensive or exhaustive and was prepared mainly to highlight the potential use of Foa toxins for selecting date palm individuals with a suitable resistance level to bayoud using toxin-based selective media. PMID:16125651

  2. Pathogenicity and mycotoxin production by Fusarium proliferatum isolated from onion and garlic in Serbia

    Microsoft Academic Search

    S. Stankovic; J. Levic; T. Petrovic; A. Logrieco; A. Moretti

    2007-01-01

    Fusarium proliferatum can occur on a wide range of economically important vegetable plants but its role in disease is not always well established.\\u000a In 2000 and 2001, from forty-one field samples of wilting onion and garlic plants in Serbia, F. proliferatum as the predominant fungal species was isolated from root and bulbs. Seventy isolates were firstly characterized for their\\u000a sexual

  3. Progress report on a contemporary survey of the Fusarium wilt fungus in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The last survey of Fusarium oxysporum f. sp. vasinfectum in the U.S. was conducted in 1985. Since that time, race 4, previously thought to occur only in Asia, appeared in California in 2001, causing significant problems for the San Joaquin Valley cotton industry. Also, the presence of race 8 has bee...

  4. Cross pathogenicity and vegetative compatibility of Fusarium oxysporum isolated from sugar beet

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium oxysporum f. sp. betae, which causes Fusarium yellows in sugar beet, can be highly variable in virulence and morphology, with further diversity derived due to the wide geographic distribution of sugar beet production. Little is known about factors that determine pathogenicity to sugar beet...

  5. Inactivation of Snt2, a BAH/PHD-containing transcription factor, impairs pathogenicity and increases autophagosome abundance in Fusarium oxysporum.

    PubMed

    Denisov, Youlia; Freeman, Stanley; Yarden, Oded

    2011-06-01

    The soil-borne, asexual fungus Fusarium oxysporum f.sp. melonis (FOM) is a causal agent of muskmelon wilt disease. The current study focused on the most virulent race of FOM-race 1,2. The tagged mutant D122, generated by Agrobacterium tumefaciens-mediated transformation, caused the delayed appearance of initial wilt disease symptoms, as well as a 75% reduction in pathogenicity. D122 was impaired in the gene product homologous to the Snt2-like transcription factor of Schizosaccharomyces pombe. Involvement of snt2 in the early stage of FOM pathogenesis and its requirement for host colonization were confirmed by targeted disruption followed by quantitative reverse transcription-polymerase chain reaction analysis of snt2 expression in planta. ?snt2 mutants of FOM and Neurospora crassa exhibited similar morphological abnormalities, including a reduction in conidia production and biomass accumulation, slower vegetative growth and frequent hyphal septation. In N. crassa, snt-2 is required for sexual development, as ?snt-2 mutants were unable to produce mature perithecia. Suppressive subtraction hybridization analysis of the D122 mutant versus wild-type isolate detected four genes (idi4, pdc, msf1, eEF1G) that were found previously in association with the target of rapamycin (TOR) kinase pathway. Expression of the autophagy-related idi4 and pdc genes was found to be up-regulated in the ?snt2 FOM mutant. In N. crassa, disruption of snt-2 also conferred a significant over-expression of idi4. PMID:21535351

  6. Influence of Climatic Factors on Fusarium Species Pathogenic to Cereals

    Microsoft Academic Search

    F. M. Doohan; J. Brennan; B. M. Cooke

    2003-01-01

    Fusarium head blight of small-grain cereals, ear rot of maize, seedling blight and foot rot of cereals are important diseases throughout the world. Fusarium graminearum, F. culmorum, F. poae, F. avenaceum and Microdochium nivale (formerly known as F. nivale) predominantly cause Fusarium diseases of small-grain cereals. Maize is predominantly attacked by F. graminearum, F. moniliforme, F. proliferatum and F. subglutinans.

  7. Deep 16S rRNA pyrosequencing reveals a bacterial community associated with Banana Fusarium Wilt disease suppression induced by bio-organic fertilizer application.

    PubMed

    Shen, Zongzhuan; Wang, Dongsheng; Ruan, Yunze; Xue, Chao; Zhang, Jian; Li, Rong; Shen, Qirong

    2014-01-01

    Our previous work demonstrated that application of a bio-organic fertilizer (BIO) to a banana mono-culture orchard with serious Fusarium wilt disease effectively decreased the number of soil Fusarium sp. and controlled the soil-borne disease. Because bacteria are an abundant and diverse group of soil organisms that responds to soil health, deep 16 S rRNA pyrosequencing was employed to characterize the composition of the bacterial community to investigate how it responded to BIO or the application of other common composts and to explore the potential correlation between bacterial community, BIO application and Fusarium wilt disease suppression. After basal quality control, 137,646 sequences and 9,388 operational taxonomic units (OTUs) were obtained from the 15 soil samples. Proteobacteria, Acidobacteria, Bacteroidetes, Gemmatimonadetes and Actinobacteria were the most frequent phyla and comprised up to 75.3% of the total sequences. Compared to the other soil samples, BIO-treated soil revealed higher abundances of Gemmatimonadetes and Acidobacteria, while Bacteroidetes were found in lower abundance. Meanwhile, on genus level, higher abundances compared to other treatments were observed for Gemmatimonas and Gp4. Correlation and redundancy analysis showed that the abundance of Gemmatimonas and Sphingomonas and the soil total nitrogen and ammonium nitrogen content were higher after BIO application, and they were all positively correlated with disease suppression. Cumulatively, the reduced Fusarium wilt disease incidence that was seen after BIO was applied for 1-year might be attributed to the general suppression based on a shift within the bacteria soil community, including specific enrichment of Gemmatimonas and Sphingomonas. PMID:24871319

  8. In vitro study of the growth, development and pathogenicity responses of Fusarium oxysporum to phthalic acid, an autotoxin from Lanzhou lily.

    PubMed

    Wu, Zhijiang; Yang, Liu; Wang, Ruoyu; Zhang, Yubao; Shang, Qianhan; Wang, Le; Ren, Qin; Xie, Zhongkui

    2015-08-01

    Continuous monoculture of Lanzhou lily (Lilium davidii var. unicolor Cotton) results in frequent incidence of fusarium wilt caused by Fusarium oxysporum. Phthalic acid (PA), a principal autotoxin from root exudates of Lanzhou lily, is involved in soil sickness by inducing autotoxicity. The aim of this study was to evaluate the direct allelopathic effects of PA on the growth, development and pathogenicity of F. oxysporum in vitro based on an ecologically relevant soil concentration. The results showed that PA slightly but not significantly inhibited the colony growth (mycelial growth) and fungal biomass of F. oxysporum at low concentrations ranging from 0.05 to 0.5 mM, and significantly inhibited the colony growth at the highest concentration (1 mM). None of the PA concentrations tested significantly inhibited the conidial germination and sporulation of F. oxysporum in liquid medium. However, mycotoxin (fusaric acid) yield and pathogenesis-related hydrolytic enzyme (protease, pectinase, cellulase, and amylase) activities were significantly stimulated in liquid cultures of F. oxysporum containing PA at ?0.25 mM. We conclude that PA at a soil level (i.e. 0.25 mM) is involved in plant-pathogen allelopathy as a stimulator of mycotoxin production and hydrolytic enzyme activities in F. oxysporum, which is possibly one of the mechanisms responsible for promoting the wilt disease of lily. PMID:25994089

  9. Molecular characterization of genes regulating fumonisin biosynthesis and development in maize pathogen fusarium verticilliodes 

    E-print Network

    Sagaram, Uma Shankar

    2009-05-15

    Fusarium verticillioides (Sacc.) Nirenberg (teleomorph Gibberella moniliformis Wineland) is a fungal pathogen of maize that causes ear rots and stalk rots worldwide. In addition, it produces a group of mycotoxins called fumonisins when the fungus...

  10. Molecular characterization of genes regulating fumonisin biosynthesis and development in maize pathogen fusarium verticilliodes

    E-print Network

    Sagaram, Uma Shankar

    2009-05-15

    Fusarium verticillioides (Sacc.) Nirenberg (teleomorph Gibberella moniliformis Wineland) is a fungal pathogen of maize that causes ear rots and stalk rots worldwide. In addition, it produces a group of mycotoxins called fumonisins when the fungus...

  11. Characterization of the Fusarium wilt resistance Fom - 2 gene in melon

    Microsoft Academic Search

    A. Oumouloud; M. Mokhtari; H. Chikh-Rouhou; M. S. Arnedo-Andrés; R. González-Torres; J. M. Álvarez

    The melon gene Fom-2, which confers resistance to Fusarium oxysporum f.sp. melonis (Fom) races 0 and 1, has been previously characterized by map-based cloning, and it encodes a protein with a nucleotide binding\\u000a site (NBS) and leucine-rich repeats (LRRs). Here, we used the primer Fom2-LRR1639 to clone and sequence a partial LRR region of the Fom-2 gene in 11 melon

  12. THE PATHOGENICITY AND DNA POLYMORPHISM OF FUSARIUM OXYSPORUM ORIGINATING FROM DIANTHUS CARYOPHYLLUS, GYPSOPHILA SPP. AND SOIL

    Microsoft Academic Search

    M. Werner; L. Irzykowska

    A number of Fusarium oxysporum pathogenic isolates originating from Dianthus caryophyllus, Gypsophila paniculata, G. repens and non-pathogenic strains obtained from soil was screened for pathogenicity and genetic variation. RAPD analysis con- ducted with arbitrary 10-mer primers gave 23 RAPD markers resulted from the DNA polymorphism. Clustering analysis based on RAPD fingerprint data revealed several distinct groups within F. oxysporum which

  13. Petunia Floral Defensins with Unique Prodomains as Novel Candidates for Development of Fusarium Wilt Resistance in Transgenic Banana Plants

    PubMed Central

    Ghag, Siddhesh B.; Shekhawat, Upendra K. Singh; Ganapathi, Thumballi R.

    2012-01-01

    Antimicrobial peptides are a potent group of defense active molecules that have been utilized in developing resistance against a multitude of plant pathogens. Floral defensins constitute a group of cysteine-rich peptides showing potent growth inhibition of pathogenic filamentous fungi especially Fusarium oxysporum in vitro. Full length genes coding for two Petunia floral defensins, PhDef1 and PhDef2 having unique C- terminal 31 and 27 amino acid long predicted prodomains, were overexpressed in transgenic banana plants using embryogenic cells as explants for Agrobacterium–mediated genetic transformation. High level constitutive expression of these defensins in elite banana cv. Rasthali led to significant resistance against infection of Fusarium oxysporum f. sp. cubense as shown by in vitro and ex vivo bioassay studies. Transgenic banana lines expressing either of the two defensins were clearly less chlorotic and had significantly less infestation and discoloration in the vital corm region of the plant as compared to untransformed controls. Transgenic banana plants expressing high level of full-length PhDef1 and PhDef2 were phenotypically normal and no stunting was observed. In conclusion, our results suggest that high-level constitutive expression of floral defensins having distinctive prodomains is an efficient strategy for development of fungal resistance in economically important fruit crops like banana. PMID:22745785

  14. Genome-Wide Analysis in Three Fusarium Pathogens Identifies Rapidly Evolving Chromosomes and Genes Associated with Pathogenicity

    PubMed Central

    Sperschneider, Jana; Gardiner, Donald M.; Thatcher, Louise F.; Lyons, Rebecca; Singh, Karam B.; Manners, John M.; Taylor, Jennifer M.

    2015-01-01

    Pathogens and hosts are in an ongoing arms race and genes involved in host–pathogen interactions are likely to undergo diversifying selection. Fusarium plant pathogens have evolved diverse infection strategies, but how they interact with their hosts in the biotrophic infection stage remains puzzling. To address this, we analyzed the genomes of three Fusarium plant pathogens for genes that are under diversifying selection. We found a two-speed genome structure both on the chromosome and gene group level. Diversifying selection acts strongly on the dispensable chromosomes in Fusarium oxysporum f. sp. lycopersici and on distinct core chromosome regions in Fusarium graminearum, all of which have associations with virulence. Members of two gene groups evolve rapidly, namely those that encode proteins with an N-terminal [SG]-P-C-[KR]-P sequence motif and proteins that are conserved predominantly in pathogens. Specifically, 29 F. graminearum genes are rapidly evolving, in planta induced and encode secreted proteins, strongly pointing toward effector function. In summary, diversifying selection in Fusarium is strongly reflected as genomic footprints and can be used to predict a small gene set likely to be involved in host–pathogen interactions for experimental verification. PMID:25994930

  15. Genome-Wide Analysis in Three Fusarium Pathogens Identifies Rapidly Evolving Chromosomes and Genes Associated with Pathogenicity.

    PubMed

    Sperschneider, Jana; Gardiner, Donald M; Thatcher, Louise F; Lyons, Rebecca; Singh, Karam B; Manners, John M; Taylor, Jennifer M

    2015-01-01

    Pathogens and hosts are in an ongoing arms race and genes involved in host-pathogen interactions are likely to undergo diversifying selection. Fusarium plant pathogens have evolved diverse infection strategies, but how they interact with their hosts in the biotrophic infection stage remains puzzling. To address this, we analyzed the genomes of three Fusarium plant pathogens for genes that are under diversifying selection. We found a two-speed genome structure both on the chromosome and gene group level. Diversifying selection acts strongly on the dispensable chromosomes in Fusarium oxysporum f. sp. lycopersici and on distinct core chromosome regions in Fusarium graminearum, all of which have associations with virulence. Members of two gene groups evolve rapidly, namely those that encode proteins with an N-terminal [SG]-P-C-[KR]-P sequence motif and proteins that are conserved predominantly in pathogens. Specifically, 29 F. graminearum genes are rapidly evolving, in planta induced and encode secreted proteins, strongly pointing toward effector function. In summary, diversifying selection in Fusarium is strongly reflected as genomic footprints and can be used to predict a small gene set likely to be involved in host-pathogen interactions for experimental verification. PMID:25994930

  16. The application of high-throughput AFLP's in assessing genetic diversity in Fusarium oxysporum f. sp. cubense

    Microsoft Academic Search

    Susan Groenewald; Noëlani Van Den Berg; Walter F. O. Marasas; Altus Viljoen

    2006-01-01

    Fusarium oxysporum f. sp. cubense (Foc) is responsible for fusarium wilt of bananas. The pathogen consists of several variants that are divided into three races and 21 vegetative compatibility groups (VCGs). Several DNA-based techniques have previously been used to analyse the worldwide population of Foc, sometimes yielding results that were not always consistent. In this study, the high-resolution genotyping method

  17. Fusarium azukicola sp. nov., an exotic azuki bean root-rot pathogen in Hokkaido, Japan

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We report on the phenotypic, molecular phylogenetic and pathogenic characterization of a novel azuki bean (Vigna angularis) root-rot (BRR) pathogen from Hokkaido, Japan, which is formally described herein as Fusarium azukicola. This species can be distinguished phenotypically from the other Phaseolu...

  18. Tomato Genome-Wide Transcriptional Responses to Fusarium Wilt and Tomato Mosaic Virus

    PubMed Central

    Andolfo, Giuseppe; Ferriello, Francesca; Tardella, Luca; Ferrarini, Alberto; Sigillo, Loredana; Frusciante, Luigi; Ercolano, Maria Raffaella

    2014-01-01

    Since gene expression approaches constitute a starting point for investigating plant–pathogen systems, we performed a transcriptional analysis to identify a set of genes of interest in tomato plants infected with F. oxysporum f. sp. lycopersici (Fol) and Tomato Mosaic Virus (ToMV). Differentially expressed tomato genes upon inoculation with Fol and ToMV were identified at two days post-inoculation. A large overlap was found in differentially expressed genes throughout the two incompatible interactions. However, Gene Ontology enrichment analysis evidenced specific categories in both interactions. Response to ToMV seems more multifaceted, since more than 70 specific categories were enriched versus the 30 detected in Fol interaction. In particular, the virus stimulated the production of an invertase enzyme that is able to redirect the flux of carbohydrates, whereas Fol induced a homeostatic response to prevent the fungus from killing cells. Genomic mapping of transcripts suggested that specific genomic regions are involved in resistance response to pathogen. Coordinated machinery could play an important role in prompting the response, since 60% of pathogen receptor genes (NB-ARC-LRR, RLP, RLK) were differentially regulated during both interactions. Assessment of genomic gene expression patterns could help in building up models of mediated resistance responses. PMID:24804963

  19. Ultrastructural and immunocytochemical investigation of pathogen development and host responses in resistant and susceptible wheat spikes infected by Fusarium culmorum

    Microsoft Academic Search

    Z. Kang; H. Buchenauer

    2000-01-01

    Pathogen development and host responses in wheat spikes of resistant and susceptible cultivars infected by Fusarium culmorum causing Fusarium head blight (FHB), were investigated by means of electron microscopy as well as immunogold labelling techniques. The studies revealed similarities in the infection process and the initial spreading of the pathogen in wheat spikes between resistant and susceptible cultivars. However, the

  20. Stable integration and expression of wasabi defensin gene in "Egusi" melon (Colocynthis citrullus L.) confers resistance to Fusarium wilt and Alternaria leaf spot.

    PubMed

    Ntui, Valentine Otang; Thirukkumaran, Gunaratnam; Azadi, Pejman; Khan, Raham Sher; Nakamura, Ikuo; Mii, Masahiro

    2010-09-01

    Production of "Egusi" melon (Colocynthis citrullus L.) in West Africa is limited by fungal diseases, such as Alternaria leaf spot and Fusarium wilt. In order to engineer "Egusi" resistant to these diseases, cotyledonary explants of two "Egusi" genotypes, 'Ejagham' and NHC1-130, were transformed with Agrobacterium tumefaciens strain EHA101 harbouring wasabi defensin gene (isolated from Wasabia japonica L.) in a binary vector pEKH1. After co-cultivation for 3 days, infected explants were transferred to MS medium containing 100 mg l(-l) kanamycin to select transformed tissues. After 3 weeks of culture, adventitious shoots appeared directly along the edges of the explants. As much as 19 out of 52 (36.5%) and 25 out of 71 (35.2%) of the explants in genotype NHC1-130 and 'Ejagham', respectively, formed shoots after 6 weeks of culture. As much as 74% (14 out of 19) of the shoots regenerated in genotype NHC1-130 and 72% (18 out of 25) of those produced in genotype 'Ejagham' were transgenic. A DNA fragment corresponding to the wasabi defensin gene or the selection marker nptII was amplified by PCR from the genomic DNA of all regenerated plant clones rooted on hormone-free MS medium under the same selection pressure, suggesting their transgenic nature. Southern blot analysis confirmed successful integration of 1-5 copies of the transgene. RT-PCR, northern and western blot analyses revealed that wasabi defensin gene was expressed in transgenic lines. Transgenic lines showed increased levels of resistance to Alternaria solani, which causes Alternaria leaf spot and Fusarium oxysporum, which causes Fusarium wilt, as compared to that of untransformed plants. PMID:20552202

  1. Can an Isolate of Talaromyces Reduce the Pathogenicity of the Plant Pathogen Fusarium oxysporum f. sp. vasinfectum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Race 4 of Fusarium oxysporum f. sp. vasinfectum (Fov) is an emerging problem for cotton production in the U.S. because it is significantly more pathogenic than races 1 and 2 which are endemic to the U.S. Race 4 is a prodigious producer of the phytotoxin fusaric acid compared to races 1 and 2. When...

  2. Antagonistic activity of Bacillus subtilis SB1 and its biocontrol effect on tomato bacterial wilt

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A potential biocontrol agent of bacterial wilt, Bacillus subtilis SB1, isolated from tomato roots, showed a broad-spectrum of antimicrobial activity in in vitro experiments. It inhibited the growth of many plant pathogens, including Ralstonia solanacearum, Xanthomonas oryzae pv. oryzae, Fusarium ox...

  3. Influence of Soil Fumigation on the Fusarium-Root-knot Nematode Disease Complex of Cotton in California.

    PubMed

    Jorgenson, E C; Hyer, A H; Garber, R H; Smith, S N

    1978-07-01

    For control of the root-knot nematode, Meloidogyne incognita, and the pathogenic wilt fungus, Fusarium oxysporum, on cotton, soil fumigants were applied in the field at conventional and higher rates. Conventional rates suppressed Fusarium wilt but higher rates gave quicker early growth, better stands, less stand loss over the season, a lower percentage of plants infected with wilt, fewer plants with vascular discoloration, and fewer nematodes. The best treatment about doubled the yields of untreated controls in one experiment and quadrupled them in another. PMID:19305846

  4. Influence of Soil Fumigation on the Fusarium-Root-knot Nematode Disease Complex of Cotton in California

    PubMed Central

    Jorgenson, E. C.; Hyer, A. H.; Garber, R. H.; Smith, Shirley N.

    1978-01-01

    For control of the root-knot nematode, Meloidogyne incognita, and the pathogenic wilt fungus, Fusarium oxysporum, on cotton, soil fumigants were applied in the field at conventional and higher rates. Conventional rates suppressed Fusarium wilt but higher rates gave quicker early growth, better stands, less stand loss over the season, a lower percentage of plants infected with wilt, fewer plants with vascular discoloration, and fewer nematodes. The best treatment about doubled the yields of untreated controls in one experiment and quadrupled them in another. PMID:19305846

  5. Occurrence of Root Rot and Vascular Wilt Diseases in Roselle (Hibiscus sabdariffa L.) in Upper Egypt.

    PubMed

    Hassan, Naglaa; Shimizu, Masafumi; Hyakumachi, Mitsuro

    2014-03-01

    Roselle (Hibiscus sabdariffa L.) family Malvaceae is an important crop used in food, cosmetics and pharmaceutics industries. Roselle is cultivated mainly in Upper Egypt (Qena and Aswan governorates) producing 94% of total production. Root rot disease of roselle is one of the most important diseases that attack both seedlings and adult plants causing serious losses in crop productivity and quality. The main objective of the present study is to identify and characterize pathogens associated with root rot and wilt symptoms of roselle in Qena, Upper Egypt and evaluate their pathogenicity under greenhouse and field condition. Fusarium oxysporum, Macrophomina phaseolina, Fusarium solani, Fusarium equiseti and Fusarium semitectum were isolated from the natural root rot diseases in roselle. All isolated fungi were morphologically characterized and varied in their pathogenic potentialities. They could attack roselle plants causing damping-off and root rot/wilt diseases in different pathogenicity tests. The highest pathogenicity was caused by F. oxysporum and M. phaseolina followed by F. solani. The least pathogenic fungi were F. equiseti followed by F. semitectum. It obviously noted that Baladi roselle cultivar was more susceptible to infection with all tested fungi than Sobhia 17 under greenhouse and field conditions. This is the first report of fungal pathogens causing root rot and vascular wilt in roselle in Upper Egypt. PMID:24808737

  6. Occurrence of Root Rot and Vascular Wilt Diseases in Roselle (Hibiscus sabdariffa L.) in Upper Egypt

    PubMed Central

    Hassan, Naglaa; Shimizu, Masafumi

    2014-01-01

    Roselle (Hibiscus sabdariffa L.) family Malvaceae is an important crop used in food, cosmetics and pharmaceutics industries. Roselle is cultivated mainly in Upper Egypt (Qena and Aswan governorates) producing 94% of total production. Root rot disease of roselle is one of the most important diseases that attack both seedlings and adult plants causing serious losses in crop productivity and quality. The main objective of the present study is to identify and characterize pathogens associated with root rot and wilt symptoms of roselle in Qena, Upper Egypt and evaluate their pathogenicity under greenhouse and field condition. Fusarium oxysporum, Macrophomina phaseolina, Fusarium solani, Fusarium equiseti and Fusarium semitectum were isolated from the natural root rot diseases in roselle. All isolated fungi were morphologically characterized and varied in their pathogenic potentialities. They could attack roselle plants causing damping-off and root rot/wilt diseases in different pathogenicity tests. The highest pathogenicity was caused by F. oxysporum and M. phaseolina followed by F. solani. The least pathogenic fungi were F. equiseti followed by F. semitectum. It obviously noted that Baladi roselle cultivar was more susceptible to infection with all tested fungi than Sobhia 17 under greenhouse and field conditions. This is the first report of fungal pathogens causing root rot and vascular wilt in roselle in Upper Egypt. PMID:24808737

  7. Pseudomonads: major antagonistic endophytic bacteria to suppress bacterial wilt pathogen, Ralstonia solanacearum in the eggplant ( Solanum melongena L.)

    Microsoft Academic Search

    R. Ramesh; A. A. Joshi; M. P. Ghanekar

    2009-01-01

    Endophytic bacteria of eggplant, cucumber and groundnut were isolated from different locations of Goa, India. Based on in vitro\\u000a screening, 28 bacterial isolates which effectively inhibited Ralstonia solanacearum, a bacterial wilt pathogen of the eggplant were characterized and identified. More than 50% of these isolates were Pseudomonas fluorescens in which a vast degree of variability was found to exist when biochemical

  8. Functional genomic studies of pathogenicity in Fusarium graminearum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Head blight or scab caused by Fusarium graminearum is a disease of wheat and barley that occurs worldwide and that has great impact on U.S. agriculture and society. Infested cereals are often contaminated with trichothecene and estrogenic mycotoxins. To better understand fungal pathogenesis and deve...

  9. BIOLOGICAL, PATHOGENIC, AND MOLECULAR CHARACTERIZATION OF FUSARIUM SOLANI F. SP. GLYCINES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean sudden death syndrome (SDS) is caused by Fusarium solani f. sp. glycines (FSG). Over the last 5 years an internationsl collection of FSG isolates has been established and maintained at the National Soybean Pathogen Collection Center. FSG isolates grew slowly and appeared reddish light blue t...

  10. FUMONISIN PRODUCTION IN THE CORN PATHOGEN FUSARIUM VERTICILLIOIDES: THE GENETIC BASIS OF NATURALLY OCCURRING CHEMICAL VARIATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fumonisins are polyketide-derived mycotoxins produced by the maize pathogen Fusarium verticillioides. Previous analyses identified naturally occurring variants of the fungus that are deficient in fumonisin C-10 hydroxylation or that do not produce any fumonisins. In the current study, gene deletio...

  11. The Fusarium graminearum genome reveals a link between localized polymorphism and pathogen specialization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The filamentous fungus Fusarium graminearum is a major destructive pathogen of cultivated cereals. We have sequenced and annotated the F. graminearum genome, and found it includes very few repetitive sequences. We experimentally demonstrate that repeats are mutated by the process of repeat-induced p...

  12. A fungal symbiont of plant-roots modulates mycotoxin gene expression in the pathogen Fusarium sambucinum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium trichothecenes are fungal toxins that cause disease on infected plants and, more importantly, health problems for humans and animals that consume infected fruits or vegetables. Unfortunately, there are few methods for controlling the growth of mycotoxin production pathogens. In this study, ...

  13. Fusarium verticillioides chitin synthases CHS5 and CHS7 are required for normal growth and pathogenicity

    Microsoft Academic Search

    Troy M. LarsonDavid; David F. Kendra; Mark Busman; Daren W. Brown

    2011-01-01

    Fusarium verticillioides is both an endophyte and a pathogen of maize and is a health threat in many areas of the world because it can contaminate\\u000a maize with fumonisins, a toxic secondary metabolite. We identified eight putative chitin synthase (CHS) genes in F. verticillioides genomic sequence, and phylogenetic evidence shows that they group into seven established CHS gene classes. We

  14. Phylogenetic analysis based on the PKS gene involved in fusaric acid biosynthesis production reveals close relationship between US race 1 lineage isolates & Australian biotype isolates of Fusarium Oxysporum f. sp. Vasinfectum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Isolates of Fusarium oxysporum f. sp. vasinfectum, the causal agent of fusarium wilt of cotton, vary significantly in their virulence. Isolates have been further subcategorized into pathogenic races based on their differential interaction with host genotypes. Phylogenetic analysis based on three n...

  15. Characterization of a population of Fusarium oxysporum, from sugar beet, using the population structure of putative pathogenicity genes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    WEBB, KIMBERLY M.*, PAUL COVEY, BRETT KUWITZKY, AND MIA HANSON, USDA-ARS, Sugar Beet Research Unit, 1701 Centre Ave., Fort Collins, CO 80526. Characterization of a population of Fusarium oxysporum, from sugar beet, using the population structure of putative pathogenicity genes. Fusarium oxysp...

  16. GENOMIC ANALYSIS OF HOST-PATHOGEN INTERACTION BETWEEN FUSARIUM GRAMINEARUM AND WHEAT DURING EARLY STAGES OF DISEASE DEVELOPMENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium graminearum strains responsible for causing the plant disease Fusarium head blight vary greatly in their ability to cause disease and produce mycotoxins on wheat. With the goal of understanding fungal gene expression related to pathogenicity, three cDNA libraries were created by suppression...

  17. Tomatidine and lycotetraose, hydrolysis products of ?-tomatine by Fusarium oxysporum tomatinase, suppress induced defense responses in tomato cells

    Microsoft Academic Search

    Shin-ichi Ito; Tomomi Eto; Shuhei Tanaka; Naoki Yamauchi; Hiroyuki Takahara; Tsuyoshi Ikeda

    2004-01-01

    Many fungal pathogens of tomato produce extracellular enzymes, collectively known as tomatinases, that detoxify the preformed antifungal steroidal glycoalkaloid ?-tomatine. Tomatinase from the vascular wilt pathogen of tomato Fusarium oxysporum f. sp. lycopersici cleaves ?-tomatine into the aglycon tomatidine (Td) and the tetrasaccharide lycotetraose (Lt). Although modes of action of ?-tomatine have been extensively studied, those of Td and Lt

  18. Watermelon wilt studies: seed-borne fusaria, fungicide trials, and host range of the pathogen

    E-print Network

    McLaughlin, Randy Joe

    1981-01-01

    etode ~Nloido yne . arenaria was present in the soil. Miltino and root necrosis was also was also observed to significantly increase in Charleston Gray. In- creased occurrence of wilt was observed to occur at intermediate pop- ulations of the fungus...

  19. Watermelon wilt studies: seed-borne fusaria, fungicide trials, and host range of the pathogen 

    E-print Network

    McLaughlin, Randy Joe

    1981-01-01

    (44) also found that manipulation of nitrogen sources was ineffective on "old" land. Several approaches for the chemical control of watermelon wilt have been studied; seed treatment (35), soil fumigation (43, 58, 85), and soil fungicide drenches... (58). As a rule, chemical treatment has been found most effective on infrequently-cropped land. A more detailed review of chemical controls is included in Chapter I I I. Control of watermelon wilt through host resistance has been studied by many...

  20. Ultrastructural and cell wall modifications during infection of Eucalyptus viminalis roots by a pathogenic Fusarium oxysporum strain

    Microsoft Academic Search

    Maria-Isabel Salerno; Silvio Gianinazzi; Christine Arnould; Vivienne Gianinazzi-Pearson

    2004-01-01

    Fusarium species are soil-borne fungal pathogens that produce a variety of disease symptoms when attacking crop plants. The mode of root colonization of Eucalyptus viminalis seedlings by a pathogenic F. oxyporum strain (Foeu1) at the ultrastructural level and changes in cell wall pectin during host pathogen interactions are described. Root systems of E. viminalis plants were inoculated with F. oxysporum

  1. Incidence of Fusarium wilt of cotton as affected by pathogen propagule type, age and source 

    E-print Network

    McEntee, James Philip

    1989-01-01

    zones of Australia, China, the Soviet Union, the Far East, Africa, and North and South America (96). The United States, which produced an estimated 14. 7 million bales (218 kg/bale) on 4. 7 million ha in 1988 currently ranks second in cotton... production behind China, with 21 million bales harvested on 5. 5 million ha. Texas is ranked first in cotton production in the United States with an annual production of 3. 6 million bales from 2. 2 million ha (1981-1985); however, hectares planted...

  2. Incidence of Fusarium wilt of cotton as affected by pathogen propagule type, age and source

    E-print Network

    McEntee, James Philip

    1989-01-01

    zones of Australia, China, the Soviet Union, the Far East, Africa, and North and South America (96). The United States, which produced an estimated 14. 7 million bales (218 kg/bale) on 4. 7 million ha in 1988 currently ranks second in cotton... production behind China, with 21 million bales harvested on 5. 5 million ha. Texas is ranked first in cotton production in the United States with an annual production of 3. 6 million bales from 2. 2 million ha (1981-1985); however, hectares planted...

  3. The Genome Sequence of the Fungal Pathogen Fusarium virguliforme That Causes Sudden Death Syndrome in Soybean

    PubMed Central

    Srivastava, Subodh K.; Huang, Xiaoqiu; Brar, Hargeet K.; Fakhoury, Ahmad M.; Bluhm, Burton H.; Bhattacharyya, Madan K.

    2014-01-01

    Fusarium virguliforme causes sudden death syndrome (SDS) of soybean, a disease of serious concern throughout most of the soybean producing regions of the world. Despite the global importance, little is known about the pathogenesis mechanisms of F. virguliforme. Thus, we applied Next-Generation DNA Sequencing to reveal the draft F. virguliforme genome sequence and identified putative pathogenicity genes to facilitate discovering the mechanisms used by the pathogen to cause this disease. Methodology/Principal Findings We have generated the draft genome sequence of F. virguliforme by conducting whole-genome shotgun sequencing on a 454 GS-FLX Titanium sequencer. Initially, single-end reads of a 400-bp shotgun library were assembled using the PCAP program. Paired end sequences from 3 and 20 Kb DNA fragments and approximately 100 Kb inserts of 1,400 BAC clones were used to generate the assembled genome. The assembled genome sequence was 51 Mb. The N50 scaffold number was 11 with an N50 Scaffold length of 1,263 Kb. The AUGUSTUS gene prediction program predicted 14,845 putative genes, which were annotated with Pfam and GO databases. Gene distributions were uniform in all but one of the major scaffolds. Phylogenic analyses revealed that F. virguliforme was closely related to the pea pathogen, Nectria haematococca. Of the 14,845 F. virguliforme genes, 11,043 were conserved among five Fusarium species: F. virguliforme, F. graminearum, F. verticillioides, F. oxysporum and N. haematococca; and 1,332 F. virguliforme-specific genes, which may include pathogenicity genes. Additionally, searches for candidate F. virguliforme pathogenicity genes using gene sequences of the pathogen-host interaction database identified 358 genes. Conclusions The F. virguliforme genome sequence and putative pathogenicity genes presented here will facilitate identification of pathogenicity mechanisms involved in SDS development. Together, these resources will expedite our efforts towards discovering pathogenicity mechanisms in F. virguliforme. This will ultimately lead to improvement of SDS resistance in soybean. PMID:24454689

  4. Detoxification of the fusarium toxin fusaric acid by the soil fungus aspergillus tubingensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fungal pathogen Fusarium oxysporum f. sp. vasinfectum (F.o.v.) causes cotton wilt and produces the toxin fusaric acid (FA). Previous research indicates that in the high producing strains of F.o.v., FA plays an important role in virulence. To address the problems of emerging virulent isolates su...

  5. The Tomato Wilt Fungus Fusarium oxysporum f. sp. lycopersici shares Common Ancestors with Nonpathogenic F. oxysporum isolated from Wild Tomatoes in the Peruvian Andes

    PubMed Central

    Inami, Keigo; Kashiwa, Takeshi; Kawabe, Masato; Onokubo-Okabe, Akiko; Ishikawa, Nobuko; Pérez, Enrique Rodríguez; Hozumi, Takuo; Caballero, Liliana Aragón; de Baldarrago, Fatima Cáceres; Roco, Mauricio Jiménez; Madadi, Khalid A.; Peever, Tobin L.; Teraoka, Tohru; Kodama, Motoichiro; Arie, Tsutomu

    2014-01-01

    Fusarium oxysporum is an ascomycetous fungus that is well-known as a soilborne plant pathogen. In addition, a large population of nonpathogenic F. oxysporum (NPF) inhabits various environmental niches, including the phytosphere. To obtain an insight into the origin of plant pathogenic F. oxysporum, we focused on the tomato (Solanum lycopersicum) and its pathogenic F. oxysporum f. sp. lycopersici (FOL). We collected F. oxysporum from wild and transition Solanum spp. and modern cultivars of tomato in Chile, Ecuador, Peru, Mexico, Afghanistan, Italy, and Japan, evaluated the fungal isolates for pathogenicity, VCG, mating type, and distribution of SIX genes related to the pathogenicity of FOL, and constructed phylogenies based on ribosomal DNA intergenic spacer sequences. All F. oxysporum isolates sampled were genetically more diverse than FOL. They were not pathogenic to the tomato and did not carry SIX genes. Certain NPF isolates including those from wild Solanum spp. in Peru were grouped in FOL clades, whereas most of the NPF isolates were not. Our results suggested that the population of NPF isolates in FOL clades gave rise to FOL by gaining pathogenicity. PMID:24909710

  6. Antifungal activity of a synthetic cationic peptide against the plant pathogens Colletotrichum graminicola and three Fusarium species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A small cationic peptide (JH8944) was tested for activity against a number of pathogens of agricultural crops. JH8944 inhibited conidium growth in most of the tested plant pathogens with a dose of 50 µg ml 1, although one isolate of Fusarium oxysporum was inhibited at 5 µg ml 1. Most conidia of Fusa...

  7. Molecular Characterization of MADS-BOX Transcription Factors and Analysis of Field Population Diversity in the Maize Pathogen Fusarium verticillioides 

    E-print Network

    Ortiz, Carlos S

    2013-04-10

    . verticillioides ETS collection against genomic sequences of F. graminearum and two non-pathogenic fungi (Aspergillus nidulans and Neurospora crassa) in order to identify Fusarium genes critical for plant disease. Their analysis identified 39 unique Fusarium... by the binding of external stimuli to G-protein receptors located in the plasma membrane. Such binding leads to the dissociation of a protein complex known as the heterotrimeric G protein and leads to the subsequent activation of MAP kinase and cAMP pathways...

  8. Identification of pathogenicity-related genes in the vascular wilt fungus verticillium dahliae by agrobacterium tumefaciens-mediated t-DNA insertional mutagenesis.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Verticillium dahliae is the causal agent of vascular wilt in many economically important crops worldwide. Identification of genes that underpin pathogenicity or virulence may suggest targets for alternative control methods for this fungus. In this study, Agrobacterium tumefaciens-mediated transform...

  9. Effects of arbuscular mycorrhiza (AM) on health of Linum usitatissimum L. infected by fungal pathogens

    Microsoft Academic Search

    G. D. Dugassa; H. von Alten; F. Schönbeck

    1996-01-01

    Effects of arbuscular mycorrhizal (AM) symbiosis on health ofLinum usitatissimum infected by fungal pathogens were investigated exemplarily. Physiological and biochemical analyses were done to explain the mechanisms underlying the AM effects. AM plants showed increased resistance against the wilt pathogen (Fusarium oxysporum f. sp.lini), the level of this effects depended on the plant cultivars which all showed the same level

  10. Development of molecular markers linked to the Fom-1 locus for resistance to Fusarium race 2 in melon

    Microsoft Academic Search

    Ali Oumouloud; Maria Soledad Arnedo-Andres; Rafael Gonzalez-Torres; Jose María Alvarez

    2008-01-01

    Fusarium wilt, caused by Fusarium oxysporum f. sp. melonis (F.o.m), is a worldwide soil-borne disease of melon (Cucumis melo L.). The most effective control measure available is the use of resistant varieties. Resistance to races 0 and 2 of this\\u000a fungal pathogen is conditioned by the dominant gene Fom-1. An F2 population derived from the ‘Charentais-Fom1’ × ‘TRG-1551’ cross was used in

  11. The effect of growth-regulators and nutrition on the development of Verticillium wilt of cotton 

    E-print Network

    Ranney, Carleton David

    1959-01-01

    . Encouraging results have been obtained in the control of Dutch elm disease (13, 53, 54), Fusarium wilt of carnations (42), and Fusarium wilt of tomatoes (10, 41), and the X virus disease of peach (39, 40) by using chemo- therapeutants. An excellent... are not uncommon. Verticillium wilt is potentially the most destructive disease throughout these areas. 2 The present possibilities of controlling Verticillium wilt are limited. The causal organism incites a vascular wilt; it enters through the root system...

  12. HapX-Mediated Iron Homeostasis Is Essential for Rhizosphere Competence and Virulence of the Soilborne Pathogen Fusarium oxysporum[C][W][OA

    PubMed Central

    López-Berges, Manuel S.; Capilla, Javier; Turrà, David; Schafferer, Lukas; Matthijs, Sandra; Jöchl, Christoph; Cornelis, Pierre; Guarro, Josep; Haas, Hubertus; Di Pietro, Antonio

    2012-01-01

    Soilborne fungal pathogens cause devastating yield losses and are highly persistent and difficult to control. During the infection process, these organisms must cope with limited availability of iron. Here we show that the bZIP protein HapX functions as a key regulator of iron homeostasis and virulence in the vascular wilt fungus Fusarium oxysporum. Deletion of hapX does not affect iron uptake but causes derepression of genes involved in iron-consuming pathways, leading to impaired growth under iron-depleted conditions. F. oxysporum strains lacking HapX are reduced in their capacity to invade and kill tomato (Solanum lycopersicum) plants and immunodepressed mice. The virulence defect of ?hapX on tomato plants is exacerbated by coinoculation of roots with a biocontrol strain of Pseudomonas putida, but not with a siderophore-deficient mutant, indicating that HapX contributes to iron competition of F. oxysporum in the tomato rhizosphere. These results establish a conserved role for HapX-mediated iron homeostasis in fungal infection of plants and mammals. PMID:22968717

  13. Analysis of Pineapple Mealybug Wilt Associated Virus -1 and -2 for Potential RNA Silencing Suppressors and Pathogenicity Factors

    PubMed Central

    Dey, Kishore K.; Borth, Wayne B.; Melzer, Michael J.; Wang, Ming-Li; Hu, John S.

    2015-01-01

    Higher plants use RNA silencing to defend against viral infections. As a counter defense, plant viruses have evolved proteins that suppress RNA silencing. Mealybug wilt of pineapple (MWP), an important disease of pineapple, has been associated with at least three distinct viruses, Pineapple mealybug wilt associated virus -1, -2, and -3 (PMWaV-1, -2, and -3). Selected open reading frames (ORFs) of PMWaV-1 and PMWaV-2 were screened for their local and systemic suppressor activities in Agrobacterium-mediated transient assays using green fluorescent protein (GFP) in Nicotiana benthamiana. Results indicate that PMWaV-2 utilizes a multiple-component RNA silencing suppression mechanism. Two proteins, p20 and CP, target both local and systemic silencing in N. benthamiana, while the p22 and CPd proteins target only systemic silencing. In the related virus PMWaV-1, we found that only one of the encoded proteins, p61, had only systemic suppressor activity. Of all the proteins tested from both viruses, only the PMWaV-2 p20 protein suppressed local silencing induced by double-stranded RNA (dsRNA), but only when low levels of inducing dsRNA were used. None of the proteins analyzed could interfere with the short distance spread of silencing. We examined the mechanism of systemic suppression activity by investigating the effect of PMWaV-2-encoded p20 and CP proteins on secondary siRNAs. Our results suggest that the PMWaV-2 p20 and CP proteins block the systemic silencing signal by repressing production of secondary siRNAs. We also demonstrate that the PMWaV-2 p20 and p22 proteins enhanced the pathogenicity of Potato virus X in N. benthamiana. PMID:25751306

  14. Analysis of pineapple mealybug wilt associated virus -1 and -2 for potential RNA silencing suppressors and pathogenicity factors.

    PubMed

    Dey, Kishore K; Borth, Wayne B; Melzer, Michael J; Wang, Ming-Li; Hu, John S

    2015-03-01

    Higher plants use RNA silencing to defend against viral infections. As a counter defense, plant viruses have evolved proteins that suppress RNA silencing. Mealybug wilt of pineapple (MWP), an important disease of pineapple, has been associated with at least three distinct viruses, Pineapple mealybug wilt associated virus -1, -2, and -3 (PMWaV-1, -2, and -3). Selected open reading frames (ORFs) of PMWaV-1 and PMWaV-2 were screened for their local and systemic suppressor activities in Agrobacterium-mediated transient assays using green fluorescent protein (GFP) in Nicotiana benthamiana. Results indicate that PMWaV-2 utilizes a multiple-component RNA silencing suppression mechanism. Two proteins, p20 and CP, target both local and systemic silencing in N. benthamiana, while the p22 and CPd proteins target only systemic silencing. In the related virus PMWaV-1, we found that only one of the encoded proteins, p61, had only systemic suppressor activity. Of all the proteins tested from both viruses, only the PMWaV-2 p20 protein suppressed local silencing induced by double-stranded RNA (dsRNA), but only when low levels of inducing dsRNA were used. None of the proteins analyzed could interfere with the short distance spread of silencing. We examined the mechanism of systemic suppression activity by investigating the effect of PMWaV-2-encoded p20 and CP proteins on secondary siRNAs. Our results suggest that the PMWaV-2 p20 and CP proteins block the systemic silencing signal by repressing production of secondary siRNAs. We also demonstrate that the PMWaV-2 p20 and p22 proteins enhanced the pathogenicity of Potato virus X in N. benthamiana. PMID:25751306

  15. Distinct colonization patterns and cDNA-AFLP transcriptome profiles in compatible and incompatible interactions between melon and different races of Fusarium oxysporum f. sp. melonis

    Microsoft Academic Search

    Sara Sestili; Annalisa Polverari; Laura Luongo; Alberto Ferrarini; Michele Scotton; Jamshaid Hussain; Massimo Delledonne; Nadia Ficcadenti; Alessandra Belisario

    2011-01-01

    Background  \\u000a Fusarium oxysporum f. sp. melonis Snyd. & Hans. (FOM) causes Fusarium wilt, the most important infectious disease of melon (Cucumis melo L.). The four known races of this pathogen can be distinguished only by infection on appropriate cultivars. No molecular\\u000a tools are available that can discriminate among the races, and the molecular basis of compatibility and disease progression\\u000a are

  16. Surfactin A production and isoforms characterizations in strains of Bacillus mojavensis for control of a maize pathogen, Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The endophytic bacterium, Bacillus mojavensis, RRC 101 controls fungal diseases in maize and other plants. The bacterium and its cultural extracts have been shown to be antagonistic to the pathogenic and mycotoxic fungus, Fusarium verticillioides. An antifungal cyclic lipopeptide produced by B. moj...

  17. Structure?Activity Relationships of Antimicrobial Gallic Acid Derivatives from Pomegranate and Acacia Fruit Extracts against Potato Bacterial Wilt Pathogen.

    PubMed

    Farag, Mohamed A; Al-Mahdy, Dalia A; Salah El Dine, Riham; Fahmy, Sherifa; Yassin, Aymen; Porzel, Andrea; Brandt, Wolfgang

    2015-06-01

    Bacterial wilts of potato, tomato, pepper, and or eggplant caused by Ralstonia solanacearum are among the most serious plant diseases worldwide. In this study, the issue of developing bactericidal agents from natural sources against R. solanacearum derived from plant extracts was addressed. Extracts prepared from 25 plant species with antiseptic relevance in Egyptian folk medicine were screened for their antimicrobial properties against the potato pathogen R. solancearum by using the disc-zone inhibition assay and microtitre plate dilution method. Plants exhibiting notable antimicrobial activities against the tested pathogen include extracts from Acacia arabica and Punica granatum. Bioactivity-guided fractionation of A. arabica and P. granatum resulted in the isolation of bioactive compounds 3,5-dihydroxy-4-methoxybenzoic acid and gallic acid, in addition to epicatechin. All isolates displayed significant antimicrobial activities against R. solanacearum (MIC values 0.5-9?mg/ml), with 3,5-dihydroxy-4-methoxybenzoic acid being the most effective one with a MIC value of 0.47?mg/ml. We further performed a structure-activity relationship (SAR) study for the inhibition of R. solanacearum growth by ten natural, structurally related benzoic acids. PMID:26080741

  18. EFFECTS OF COMPOST AND LIME APPLICATION ON SOIL CHEMICAL PROPERTIES, SOIL MICROBIAL COMMUNITY, AND FUSARIUM WILT IN

    E-print Network

    Ma, Lena

    1 EFFECTS OF COMPOST AND LIME APPLICATION ON SOIL CHEMICAL PROPERTIES, SOIL MICROBIAL COMMUNITY content and fertility, and can support the growth of soil-borne pathogens. Some growers choose to apply compost as an antagonistic suppression approach to combat soil-borne disease effects on crop yields

  19. Molecular characterization of a novel hypovirus from the plant pathogenic fungus Fusarium graminearum.

    PubMed

    Li, Pengfei; Zhang, Hailong; Chen, Xiaoguang; Qiu, Dewen; Guo, Lihua

    2015-07-01

    A novel mycovirus, termed Fusarium graminearum Hypovirus 2 (FgHV2/JS16), isolated from a plant pathogenic fungus, Fusarium graminearum strain JS16, was molecularly and biologically characterized. The genome of FgHV2/JS16 is 12,800 nucleotides (nts) long, excluding the poly (A) tail. This genome has only one large putative open reading frame, which encodes a polyprotein containing three normal functional domains, papain-like protease, RNA-dependent RNA polymerase, RNA helicase, and a novel domain with homologous bacterial SMC (structural maintenance of chromosomes) chromosome segregation proteins. A defective RNA segment that is 4553-nts long, excluding the poly (A) tail, was also detected in strain JS16. The polyprotein shared significant aa identities with Cryphonectria hypovirus 1 (CHV1) (16.8%) and CHV2 (16.2%). Phylogenetic analyses based on multiple alignments of the polyprotein clearly divided the members of Hypoviridae into two major groups, suggesting that FgHV2/JS16 was a novel hypovirus of a newly proposed genus-Alphahypovirus-composed of the members of Group 1, including CHV1, CHV2, FgHV1 and Sclerotinia sclerotiorum hypovirus 2. FgHV2/JS16 was shown to be associated with hypovirulence phenotypes according to comparisons of the biological properties shared between FgHV2/JS16-infected and FgHV2/JS16-free isogenic strains. Furthermore, we demonstrated that FgHV2/JS16 infection activated the RNA interference pathway in Fusarium graminearum by relative quantitative real time RT-PCR. PMID:25781585

  20. Molecular records of micro-evolution within the Algerian population of Fusarium oxysporum f. sp. albedinis during its spread to new oases

    Microsoft Academic Search

    Diana Fernandez; Mohamed Ouinten; Abdelaziz Tantaoui; Jean-Paul Geiger

    1997-01-01

    The genetic diversity of the date palm wilt pathogen Fusarium oxysporum f. sp. albedinis in Algeria was assessed using vegetative compatibility, restriction fragment length polymorphism (RFLP) of mitochondrial DNA (mtDNA), and random amplified polymorphic DNA (RAPD). Ninety-eight isolates were collected from the main infested regions, Touat, Gourara and Mzab, and 6 isolates from Morocco were added for comparison. All isolates

  1. Tissue-specific and pathogen-inducible expression of a fusion protein containing a Fusarium-specific antibody and a fungal chitinase protects wheat against Fusarium pathogens and mycotoxins.

    PubMed

    Cheng, Wei; Li, He-Ping; Zhang, Jing-Bo; Du, Hong-Jie; Wei, Qi-Yong; Huang, Tao; Yang, Peng; Kong, Xian-Wei; Liao, Yu-Cai

    2015-06-01

    Fusarium head blight (FHB) in wheat and other small grain cereals is a globally devastating disease caused by toxigenic Fusarium pathogens. Controlling FHB is a challenge because germplasm that is naturally resistant against these pathogens is inadequate. Current control measures rely on fungicides. Here, an antibody fusion comprised of the Fusarium spp.-specific recombinant antibody gene CWP2 derived from chicken, and the endochitinase gene Ech42 from the biocontrol fungus Trichoderma atroviride was introduced into the elite wheat cultivar Zhengmai9023 by particle bombardment. Expression of this fusion gene was regulated by the lemma/palea-specific promoter Lem2 derived from barley; its expression was confirmed as lemma/palea-specific in transgenic wheat. Single-floret inoculation of independent transgenic wheat lines of the T3 to T6 generations revealed significant resistance (type II) to fungal spreading, and natural infection assays in the field showed significant resistance (type I) to initial infection. Gas chromatography-mass spectrometry analysis revealed marked reduction of mycotoxins in the grains of the transgenic wheat lines. Progenies of crosses between the transgenic lines and the FHB-susceptible cultivar Huamai13 also showed significantly enhanced FHB resistance. Quantitative real-time PCR analysis revealed that the tissue-specific expression of the antibody fusion was induced by salicylic acid drenching and induced to a greater extent by F. graminearum infection. Histochemical analysis showed substantial restriction of mycelial growth in the lemma tissues of the transgenic plants. Thus, the combined tissue-specific and pathogen-inducible expression of this Fusarium-specific antibody fusion can effectively protect wheat against Fusarium pathogens and reduce mycotoxin content in grain. PMID:25418882

  2. Characterization of Fusarium verticillioides strains isolated from maize in Italy: fumonisin production, pathogenicity and genetic variability.

    PubMed

    Covarelli, Lorenzo; Stifano, Simonetta; Beccari, Giovanni; Raggi, Lorenzo; Lattanzio, Veronica Maria Teresa; Albertini, Emidio

    2012-08-01

    Fusarium verticillioides (teleomorph Gibberella moniliformis) is the main fungal agent of ear and kernel rot of maize (Zea mays L.) worldwide, including Italy. F.verticillioides is a highly toxigenic species since it is able to produce the carcinogenic mycotoxins fumonisins. In this study, 25 F. verticillioides strains, isolated from maize in different regions of Italy were analyzed for their ability to produce fumonisins, their pathogenicity and their genetic variability. A further referenced strain of G. moniliformis isolated from maize in USA was also used as outgroup. The fumonisins B?, B?, and B? were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Pathogenicity tests were carried out by symptom observation and determination of growth parameters after inoculation of maize seeds, seedlings and wounded detached leaves. Total genomic DNA was used for Amplified Fragment Length Polymorphism (AFLP) analysis. About 20% of the analyzed strains were unable to produce fumonisins in in vitro experiments on inoculated maize flour, while, among fumonisin producers, a great variability was observed, with values ranging from 1 to 115 mg kg?¹. The different analyzed strains showed a wide range of pathogenicity in terms of effect on seed germination, seedling development and of symptoms produced on detached leaves, which were not correlated with the different in vitro fumonisin production. AFLP analysis indicated the presence of genetic diversity not only between the Italian strains and the American reference but also among the Italian isolates. PMID:22475938

  3. Effect of clove oil on plant pathogenic bacteria and bacterial wilt of tomato and geranium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We determined the antibacterial activity of clove oil against seven different genera of plant pathogenic bacteria including Gram-negative Agrobacterium tumefaciens, Erwinia carotovora pv. carotovora, Pseudomonas syringae pv. syringae, Ralstonia solanacearum, and Xanthomonas campestris pv. pelargonii...

  4. Slow sand filters effectively reduce Phytophthora after a pathogen switch from Fusarium and a simulated pump failure.

    PubMed

    Lee, Eric; Oki, Lorence R

    2013-09-15

    Slow sand filtration has been shown to effectively reduce Phytophthora zoospores in irrigation water. This experiment tested the reduction of Phytophthora colony forming units (CFUs) by slow sand filtration systems after switching the pathogen contaminating plant leachate from Fusarium to Phytophthora and the resilience of the system to a short period without water, as might be caused by a pump failure. The slow sand filtration system greatly reduced Phytophthora CFUs and transmission after switching the pathogens. In addition, Phytophthora reduction by the slow sand filter was equally effective before and after the simulated pump failure. Reduction of Fusarium was not seen by the SSFs, before or after the simulated pump failure. The results suggest that slow sand filters are effective at reducing larger organisms, such as Phytophthora zoospores, even after a pump failure or a change in pathogens. PMID:23866129

  5. Identification of the Infection Route of a Fusarium Seed Pathogen into Nondormant Bromus tectorum Seeds.

    PubMed

    Franke, JanaLynn; Geary, Brad; Meyer, Susan E

    2014-12-01

    ABSTRACT The genus Fusarium has a wide host range and causes many different forms of plant disease. These include seed rot and seedling blight diseases of cultivated plants. The diseases caused by Fusarium on wild plants are less well-known. In this study, we examined disease development caused by Fusarium sp. n on nondormant seeds of the important rangeland weed Bromus tectorum as part of broader studies of the phenomenon of stand failure or "die-off" in this annual grass. We previously isolated an undescribed species in the F. tricinctum species complex from die-off soils and showed that it is pathogenic on seeds. It can cause high mortality of nondormant B. tectorum seeds, especially under conditions of water stress, but rarely attacks dormant seeds. In this study, we used scanning electron microscopy (SEM) to investigate the mode of attack used by this pathogen. Nondormant B. tectorum seeds (i.e., florets containing caryopses) were inoculated with isolate Skull C1 macroconidia. Seeds were then exposed to water stress conditions (-1.5 MPa) for 7 days and then transferred to free water. Time lapse SEM photographs of healthy versus infected seeds revealed that hyphae under water stress conditions grew toward and culminated their attack at the abscission layer of the floret attachment scar. A prominent infection cushion, apparent macroscopically as a white tuft of mycelium at the radicle end of the seed, developed within 48 h after inoculation. Seeds that lacked an infection cushion completed germination upon transfer to free water, whereas seeds with an infection cushion were almost always killed. In addition, hyphae on seeds that did not initiate germination lacked directional growth and did not develop the infection cushion. This strongly suggests that the fungal attack is triggered by seed exudates released through the floret attachment scar at the initiation of germination. Images of cross sections of infected seeds showed that the fungal hyphae first penetrated the caryposis wall, then entered the embryo, and later ramified throughout the endosperm, completely destroying the seed. PMID:25389704

  6. Fusion proteins comprising a Fusarium-specific antibody linked to antifungal peptides protect plants against a fungal pathogen.

    PubMed

    Peschen, Dieter; Li, He-Ping; Fischer, Rainer; Kreuzaler, Fritz; Liao, Yu-Cai

    2004-06-01

    In planta expression of recombinant antibodies recognizing pathogen-specific antigens has been proposed as a strategy for crop protection. We report the expression of fusion proteins comprising a Fusarium-specific recombinant antibody linked to one of three antifungal peptides (AFPs) as a method for protecting plants against fungal diseases. A chicken-derived single-chain antibody specific to antigens displayed on the Fusarium cell surface was isolated from a pooled immunocompetent phage display library. This recombinant antibody inhibited fungal growth in vitro when fused to any of the three AFPs. Expression of the fusion proteins in transgenic Arabidopsis thaliana plants conferred high levels of protection against Fusarium oxysporum f.sp. matthiolae, whereas plants expressing either the fungus-specific antibody or AFPs alone exhibited only moderate resistance. Our results demonstrate that antibody fusion proteins may be used as effective and versatile tools for the protection of crop plants against fungal infection. PMID:15146196

  7. Pathogenic and Phylogenetic analysis of Fusarium oxysporum from Sugarbeet in Michigan and Minnesota

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium yellows of sugarbeet (Beta vulgaris L.), caused by Fusarium oxysporum Schlechtend:FR. f. sp. betae (Stewart) Snyd & Hans, can lead to significant reduction in root yield sucrose percentage, and juice purity. Fusarium yellows has become increasingly common in both Michigan and Minnesota sug...

  8. Integrated Management of Verticillium Wilt in Cotton

    E-print Network

    Behmer, Spencer T.

    Integrated Management of Verticillium Wilt in Cotton Jason E. Woodward, Extension, is an increasingly important disease of cotton on the Southern High Plains. The pathogen has a broad host range of a 2 infected with Verticillium wilt Verticillium wilt is not new to cotton producing areas

  9. Variation in sensitivity to tomatine and rishitin among isolates of Fusarium oxysporumf.sp. lycopersici, and strains not pathogenic on tomato

    Microsoft Academic Search

    P. Suleman; A. M. Tohamy; A. A. Saleh; M. A. Madkour; David C. Straney

    1996-01-01

    Studies of several fungal plant pathogens have found an association between greater virulence and increased tolerance of the host 's defense compounds among different isolates of that pathogen species. This study examined 17Fusarium oxysporumisolates to determine if tolerance of either of two fungitoxic compounds produced by tomato, rishitin and tomatine, would correlate with virulence or pathogenicity on tomato. Among the

  10. In vitro antifugal activity of medicinal plant extract against Fusarium oxysporum f. sp. lycopersici race 3 the causal agent of tomato wilt.

    PubMed

    Isaac, G S; Abu-Tahon, M A

    2014-03-01

    Medicinal plant extracts of five plants; Adhatoda vasica, Eucalyptus globulus, Lantana camara, Nerium oleander and Ocimum basilicum collected from Cairo, Egypt were evaluated against Fusarium oxysporum f. sp. lycopersici race 3 in vitro conditions using water and certain organic solvents. The results revealed that cold distilled water extracts of O. basilicum and E. globulus were the most effective ones for inhibiting the growth of F. oxysporum f. sp. lycopersici. Butanolic and ethanolic extracts of the tested plants inhibited the pathogen growth to a higher extent than water extracts. Butanolic extract of O. basilicum completely inhibited the growth of F. oxysporum f. sp. lycopersici at concentrations 1.5 and 2.0% (v/v). Butanolic extracts (2.0%) of tested plants had a strong inhibitory effect on hydrolytic enzymes; ?-glucosidase, pectin lyase and protease of F. oxysporum f. sp. lycopersici. This study has confirmed that the application of plant extracts, especially from O. basilicum for controlling F. oxysporum f. sp. lycopersici is environmentally safe, cost effective and does not disturb ecological balance. Investigations are in progress to test the efficacy of O. basilicum extract under in vivo conditions. PMID:24561899

  11. The Sfp-Type 4?-Phosphopantetheinyl Transferase Ppt1 of Fusarium fujikuroi Controls Development, Secondary Metabolism and Pathogenicity

    Microsoft Academic Search

    Philipp Wiemann; Sabine Albermann; Eva-Maria Niehaus; Lena Studt; Katharina W. von Bargen; Nelson L. Brock; Hans-Ulrich Humpf; Jeroen S. Dickschat; Bettina Tudzynski

    2012-01-01

    The heterothallic ascomycete Fusarium fujikuroi is a notorious rice pathogen causing super-elongation of plants due to the production of terpene-derived gibberellic acids (GAs) that function as natural plant hormones. Additionally, F. fujikuroi is able to produce a variety of polyketide- and non-ribosomal peptide-derived metabolites such as bikaverins, fusarubins and fusarins as well as metabolites from yet unidentified biosynthetic pathways, e.g.

  12. Genomic clustering and co-regulation of transcriptional networks in the pathogenic fungus Fusarium graminearum

    PubMed Central

    2013-01-01

    Background Genes for the production of a broad range of fungal secondary metabolites are frequently colinear. The prevalence of such gene clusters was systematically examined across the genome of the cereal pathogen Fusarium graminearum. The topological structure of transcriptional networks was also examined to investigate control mechanisms for mycotoxin biosynthesis and other processes. Results The genes associated with transcriptional processes were identified, and the genomic location of transcription-associated proteins (TAPs) analyzed in conjunction with the locations of genes exhibiting similar expression patterns. Highly conserved TAPs reside in regions of chromosomes with very low or no recombination, contrasting with putative regulator genes. Co-expression group profiles were used to define positionally clustered genes and a number of members of these clusters encode proteins participating in secondary metabolism. Gene expression profiles suggest there is an abundance of condition-specific transcriptional regulation. Analysis of the promoter regions of co-expressed genes showed enrichment for conserved DNA-sequence motifs. Potential global transcription factors recognising these motifs contain distinct sets of DNA-binding domains (DBDs) from those present in local regulators. Conclusions Proteins associated with basal transcriptional functions are encoded by genes enriched in regions of the genome with low recombination. Systematic searches revealed dispersed and compact clusters of co-expressed genes, often containing a transcription factor, and typically containing genes involved in biosynthetic pathways. Transcriptional networks exhibit a layered structure in which the position in the hierarchy of a regulator is closely linked to the DBD structural class. PMID:23805903

  13. THE ROLE OF FUSARIUM BIODIVERSITY IN PLANT PATHOGENICITY AND BIOLOGICAL CONTROL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Fusarium disease complexes of maize, wheat, and other cereal grains are biologically highly diverse. This biodiversity is believed to have a major impact on the types and levels of mycotoxins in food grains. The first dimension of complexity is at the Fusarium species level. Identification an...

  14. Novel fusarium head blight pathogens from Nepal and Louisiana revealed by multilocus genealogical concordance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was conducted to assess evolutionary relationships, species diversity, and trichothecene toxin potential of five Fusarium graminearum complex (FGSC) isolates identified as genetically novel during prior Fusarium head blight (FHB) surveys in Nepal and Louisiana. Results of a multilocus gen...

  15. MYT3, A Myb-Like Transcription Factor, Affects Fungal Development and Pathogenicity of Fusarium graminearum

    PubMed Central

    Son, Hokyoung; Choi, Gyung Ja; Kim, Jin-Cheol; Lee, Yin-Won

    2014-01-01

    We previously characterized members of the Myb protein family, MYT1 and MYT2, in Fusarium graminearum. MYT1 and MYT2 are involved in female fertility and perithecium size, respectively. To expand knowledge of Myb proteins in F. graminearum, in this study, we characterized the functions of the MYT3 gene, which encodes a putative Myb-like transcription factor containing two Myb DNA-binding domains and is conserved in the subphylum Pezizomycotina of Ascomycota. MYT3 proteins were localized in nuclei during most developmental stages, suggesting the role of MYT3 as a transcriptional regulator. Deletion of MYT3 resulted in impairment of conidiation, germination, and vegetative growth compared to the wild type, whereas complementation of MYT3 restored the wild-type phenotype. Additionally, the ?myt3 strain grew poorly on nitrogen-limited media; however, the mutant grew robustly on minimal media supplemented with ammonium. Moreover, expression level of nitrate reductase gene in the ?myt3 strain was decreased in comparison to the wild type and complemented strain. On flowering wheat heads, the ?myt3 strain exhibited reduced pathogenicity, which corresponded with significant reductions in trichothecene production and transcript levels of trichothecene biosynthetic genes. When the mutant was selfed, mated as a female, or mated as a male for sexual development, perithecia were not observed on the cultures, indicating that the ?myt3 strain lost both male and female fertility. Taken together, these results demonstrate that MYT3 is required for pathogenesis and sexual development in F. graminearum, and will provide a robust foundation to establish the regulatory networks for all Myb-like proteins in F. graminearum. PMID:24722578

  16. FUBT, a putative MFS transporter, promotes secretion of fusaric acid in the cotton pathogen Fusarium oxysporum f. sp. vasinfectum.

    PubMed

    Crutcher, Frankie K; Liu, Jinggao; Puckhaber, Lorraine S; Stipanovic, Robert D; Bell, Alois A; Nichols, Robert L

    2015-04-01

    Fusaric acid (FA) is a key component in virulence and symptom development in cotton during infection by Fusarium oxysporum. A putative major facilitator superfamily (MFS) transporter gene was identified downstream of the polyketide synthase gene responsible for the biosynthesis of FA in a region previously believed to be unrelated to the known FA gene cluster. Disruption of the transporter gene, designated FUBT, resulted in loss of FA secretion, decrease in FA production and a decrease in resistance to high concentrations of FA. Uptake of exogenous FA was unaffected in the disruption transformants, suggesting that FA enters the cell in Fusarium by an independent mechanism. Thus, FUBT is involved both in the extracellular transport of FA and in resistance of F. oxysporum to this non-specific toxin. A potential secondary resistance mechanism, the production of FA derivatives, was observed in FUBT deletion mutants. Molecular analysis of key biochemical processes in the production of FA could lead to future host plant resistance to Fusarium pathogens. PMID:25627440

  17. Transgenic expression of polygalacturonase-inhibiting proteins in Arabidopsis and wheat increases resistance to the flower pathogen Fusarium graminearum.

    PubMed

    Ferrari, S; Sella, L; Janni, M; De Lorenzo, G; Favaron, F; D'Ovidio, R

    2012-03-01

    Fusarium head blight (FHB), caused by Fusarium graminearum, is one of the most important diseases of wheat worldwide, resulting in yield losses and mycotoxin contamination. The molecular mechanisms regulating Fusarium penetration and infection are poorly understood. Beside mycotoxin production, cell wall degradation may play a role in the development of FHB. Many fungal pathogens secrete polygalacturonases (PGs) during the early stages of infection, and plants have evolved polygalacturonase-inhibiting proteins (PGIPs) to restrict pectin degradation during fungal infection. To investigate the role of plant PGIPs in restricting the development of FHB symptoms, we first used Arabidopsis thaliana, whose genome encodes two PGIPs (AtPGIP1 and AtPGIP2). Arabidopsis transgenic plants expressing either of these PGIPs under control of the CaMV 35S promoter accumulate inhibitory activity against F. graminearum PG in their inflorescences, and show increased resistance to FHB. Second, transgenic wheat plants expressing the bean PvPGIP2 in their flowers also had a significant reduction of symptoms when infected with F. graminearum. Our data suggest that PGs likely play a role in F. graminearum infection of floral tissues, and that PGIPs incorporated into wheat may be important for increased resistance to FHB. PMID:21974721

  18. Control of wilt disease of lentil through bio control agents and organic amendments in Tarai region of Uttarakhand, India.

    PubMed

    Garkoti, Ankita; Kumar, Vijay; Tripathi, H S

    2014-11-01

    The present work aimed at evaluating the efficacy of bioagents and organic amendments against lentil wilt pathogen. Field trials were carried out consecutively during Rabi 2010-11 and 2011-12 crop seasons in Randomized Block Design (RBD) with three replications, using 'Pant L-639' a popular cultivar. The plot size was 3.0 x 1.5 m2 with row spacing of 30 cm. Effect of selected bioagents and organic amendments on disease incidence, 1000 grain weight and yield kg ha' of lentil was recorded. It was observed that seed treatment with Trichoderma harizanum + Pseudomonas fluorescens significant by reduced 1.73% (2010-11) and 1.93% (2011-12) in Fusarium wilt disease incidence and increase in grain yield 507.6 kg ha(-1) and 496.0 kg ha(-1) respectively during both crop seasons. Among organic amendments, minimum wilt disease incidence of 1.69% (2010-11) and 1.81% (2011-12) and maximum grain yield 496.3 kg ha(-1) (2010-11) and 484.0 kg ha(-1) (2011-12) were observed in farm yard manure + spent compost treated plots. This indicates that these treatments have important roles in biologically based management strategies for controling Fusarium wilt disease under organic mode of lentil cultivation in Uttarakhand State. PMID:25522507

  19. The endo-beta-1,4-glucanase CelA of Clavibacter michiganensis subsp. michiganensis is a pathogenicity determinant required for induction of bacterial wilt of tomato.

    PubMed

    Jahr, H; Dreier, J; Meletzus, D; Bahro, R; Eichenlaub, R

    2000-07-01

    The phytopathogenic bacterium Clavibacter michiganensis subsp. michiganensis NCPPB382, which causes bacterial wilt and canker of tomato, harbors two plasmids, pCM1 (27.35 kb) and pCM2 (72 kb), encoding genes involved in virulence (D. Meletzus, A. Bermpohl, J. Dreier, and R. Eichenlaub, 1993, J. Bacteriol. 175:2131-2136; J. Dreier, D. Meletzus, and R. Eichenlaub, 1997, Mol. Plant-Microbe Interact. 10:195-206). The region of pCM1 carrying the endoglucanase gene celA was mapped by deletion analysis and complementation. RNA hybridization identified a 2.4-knt (kilonucleotide) transcript of the celA structural gene and the transcriptional initiation site was mapped. The celA gene encodes CelA, a protein of 78 kDa (746 amino acids) with similarity to endo-beta-1,4-glucanases of family A1 cellulases. CelA has a three-domain structure with a catalytic domain, a type IIa-like cellulose-binding domain, and a C-terminal domain. We present evidence that CelA plays a major role in pathogenicity, since wilt induction capability is obtained by endoglucanase expression in plasmid-free, nonvirulent strains and by complementation of the CelA- gene-replacement mutant CMM-H4 with the wild-type celA gene. PMID:10875331

  20. Candida and Fusarium species known as opportunistic human pathogens from customer-accessible parts of residential washing machines.

    PubMed

    Babi?, Monika Novak; Zalar, Polona; Ženko, Bernard; Schroers, Hans-Josef; Džeroski, Sašo; Gunde-Cimerman, Nina

    2015-03-01

    Energy constraints have altered consumer practice regarding the use of household washing machines. Washing machines were developed that use lower washing temperatures, smaller amounts of water and biodegradable detergents. These conditions may favour the enrichment of opportunistic human pathogenic fungi. We focused on the isolation of fungi from two user-accessible parts of washing machines that often contain microbial biofilms: drawers for detergents and rubber door seals. Out of 70 residential washing machines sampled in Slovenia, 79% were positive for fungi. In total, 72 strains belonging to 12 genera and 26 species were isolated. Among these, members of the Fusarium oxysporum and Fusarium solani species complexes, Candida parapsilosis and Exophiala phaeomuriformis represented 44% of fungi detected. These species are known as opportunistic human pathogens and can cause skin, nail or eye infections also in healthy humans. A machine learning analysis revealed that presence of detergents and softeners followed by washing temperature, represent most critical factors for fungal colonization. Three washing machines with persisting malodour that resulted in bad smelling laundry were analysed for the presence of fungi and bacteria. In these cases, fungi were isolated in low numbers (7.5 %), while bacteria Micrococcus luteus, Pseudomonas aeruginosa, and Sphingomonas species prevailed. PMID:25749362

  1. Fusaric acid is a crucial factor in the disturbance of leaf water imbalance in Fusarium-infected banana plants.

    PubMed

    Dong, Xian; Ling, Ning; Wang, Min; Shen, Qirong; Guo, Shiwei

    2012-11-01

    Fusarium wilt of banana is caused by Fusarium oxysporum f. sp. cubense infection. The initial chlorosis symptoms occur progressively from lower to upper leaves, with wilt symptoms subsequently occurring in the whole plant. To determine the effect of the pathogen infection on the gas exchange characteristics and water content in banana leaves, hydroponic experiments with pathogen inoculation were conducted in a greenhouse. Compared with control plants, infected banana seedlings showed a higher leaf temperature as determined by thermal imaging. Reduced stomatal conductance (g(s)) and transpiration rate (E) in infected plants resulted in lower levels of water loss than in control plants. Water potential in heavily diseased plants (II) was significantly reduced and the E/g(s) ratio was higher than in noninfected plants, indicating the occurrence of uncontrolled water loss not regulated by stomata in diseased plants. As no pathogen colonies were detected from the infected plant leaves, the crude toxin was extracted from the pathogen culture and evaluated about the effect on banana plant to further investigate the probable reason of these physiological changes in Fusarium-infected banana leaf. The phytotoxin fusaric acid (FA) was found in the crude toxin, and both crude toxin and pure FA had similar effects as the pathogen infection on the physiological changes in banana leaf. Additionally, FA was present at all positions in diseased plants and its concentration was positively correlated with the incidence of disease symptoms. Taken together, these observations indicated that FA secreted by the pathogen is an important factor involved in the disturbance of leaf temperature, resulting in uncontrolled leaf water loss and electrolyte leakage due to damaging the cell membrane. In conclusion, FA plays a critical role in accelerating the development of Fusarium wilt in banana plants by acting as a phytotoxin. PMID:22964424

  2. ?-Tomatine, the major saponin in tomato, induces programmed cell death mediated by reactive oxygen species in the fungal pathogen Fusarium oxysporum

    Microsoft Academic Search

    Shin-ichi Ito; Takashi Ihara; Hideyuki Tamura; Shuhei Tanaka; Tsuyoshi Ikeda; Hiroshi Kajihara; Chandrika Dissanayake; Fatma F. Abdel-Motaal; Magdi A. El-Sayed

    2007-01-01

    The tomato saponin ?-tomatine has been proposed to kill sensitive cells by binding to cell membranes followed by leakage of cell components. However, details of the modes of action of the compound on fungal cells are poorly understood. In the present study, mechanisms involved in ?-tomatine-induced cell death of fungi were examined using a filamentous pathogenic fungus Fusarium oxysporum. ?-Tomatine-induced

  3. Visualization of interactions between a pathogenic and a beneficial Fusarium strain during biocontrol of tomato foot and root rot.

    PubMed

    Bolwerk, Annouschka; Lagopodi, Anastasia L; Lugtenberg, Ben J J; Bloemberg, Guido V

    2005-07-01

    The soilborne fungus Fusarium oxysporum f. sp. radicis-lycopersici causes tomato foot and root rot (TFRR), which can be controlled by the addition of the nonpathogenic fungus F. oxysporum Fo47 to the soil. To improve our understanding of the interactions between the two Fusarium strains on tomato roots during biocontrol, the fungi were labeled using different autofluorescent proteins as markers and subsequently visualized using confocal laser scanning microscopy. The results were as follows. i) An at least 50-fold excess of Fo47over F. oxysporum f. sp. radicis-lycopersici was required to obtain control of TFRR. ii) When seedlings were planted in sand infested with spores of a single fungus, Fo47 hyphae attached to the root earlier than those of F. oxysporum f. sp. radicis-lycopersici. iii) Subsequent root colonization by F. oxysporum f. sp. radicis-lycopersici was faster and to a larger extent than that by Fo47. iv) Under disease-controlling conditions, colonization of tomato roots by the pathogenic fungus was significantly reduced. v) When the inoculum concentration of Fo47 was increased, root colonization by the pathogen was arrested at the stage of initial attachment to the root. vi) The percentage of spores of Fo47 that germinates in tomato root exudate in vitro is higher than that of the pathogen F. oxysporum f. sp. radicis-lycopersici. Based on these results, the mechanisms by which Fo47 controls TFRR are discussed in terms of i) rate of spore germination and competition for nutrients before the two fungi reach the rhizoplane; ii) competition for initial sites of attachment, intercellular junctions, and nutrients on the tomato root surface; and iii) inducing systemic resistance. PMID:16042017

  4. A Putative Transcription Factor pcs1 Positively Regulates Both Conidiation and Sexual Reproduction in the Cereal Pathogen Fusarium graminearum.

    PubMed

    Jung, Boknam; Park, Jungwook; Son, Hokyoung; Lee, Yin-Won; Seo, Young-Su; Lee, Jungkwan

    2014-09-01

    The plant pathogen Fusarium graminearum causes Fusarium head blight in cereal crops and produces mycotoxins that are harmful to animals and humans. For the initiation and spread of disease, asexual and sexual reproduction is required. Therefore, studies on fungal reproduction contribute to the development of new methods to control and maintain the fungal population. Screening a previously generated transcription factor mutant collection, we identified one putative C2H2 zinc-finger transcription factor, pcs1, which is required for both sexual and asexual reproduction. Deleting pcs1 in F. graminearum resulted in a dramatic reduction in conidial production and a complete loss of sexual reproduction. The pathways and gene ontology of pcs1-dependent genes from microarray experiments showed that several G-protein related pathways, oxidase activity, ribosome biogenesis, and RNA binding and processing were highly enriched, suggesting that pcs1 is involved in several different biological processes. Further, overexpression of pcs1 increased conidial production and resulted in earlier maturation of ascospores compared to the wild-type strain. Additionally, the vegetative growth of the overexpression mutants was decreased in nutrient-rich conditions but was not different from the wild-type strain in nutrient-poor conditions. Overall, we discovered that the pcs1 transcription factor positively regulates both conidiation and sexual reproduction and confers nutrient condition-dependent vegetative growth. PMID:25289009

  5. A Putative Transcription Factor pcs1 Positively Regulates Both Conidiation and Sexual Reproduction in the Cereal Pathogen Fusarium graminearum

    PubMed Central

    Jung, Boknam; Park, Jungwook; Son, Hokyoung; Lee, Yin-Won; Seo, Young-Su; Lee, Jungkwan

    2014-01-01

    The plant pathogen Fusarium graminearum causes Fusarium head blight in cereal crops and produces mycotoxins that are harmful to animals and humans. For the initiation and spread of disease, asexual and sexual reproduction is required. Therefore, studies on fungal reproduction contribute to the development of new methods to control and maintain the fungal population. Screening a previously generated transcription factor mutant collection, we identified one putative C2H2 zinc-finger transcription factor, pcs1, which is required for both sexual and asexual reproduction. Deleting pcs1 in F. graminearum resulted in a dramatic reduction in conidial production and a complete loss of sexual reproduction. The pathways and gene ontology of pcs1-dependent genes from microarray experiments showed that several G-protein related pathways, oxidase activity, ribosome biogenesis, and RNA binding and processing were highly enriched, suggesting that pcs1 is involved in several different biological processes. Further, overexpression of pcs1 increased conidial production and resulted in earlier maturation of ascospores compared to the wild-type strain. Additionally, the vegetative growth of the overexpression mutants was decreased in nutrient-rich conditions but was not different from the wild-type strain in nutrient-poor conditions. Overall, we discovered that the pcs1 transcription factor positively regulates both conidiation and sexual reproduction and confers nutrient condition-dependent vegetative growth. PMID:25289009

  6. Genome Sequences of Six Wheat-Infecting Fusarium Species Isolates

    PubMed Central

    Moolhuijzen, Paula M.; Manners, John M.; Wilcox, Stephen A.; Bellgard, Matthew I.

    2013-01-01

    Fusarium pathogens represent a major constraint to wheat and barley production worldwide. To facilitate future comparative studies of Fusarium species that are pathogenic to wheat, the genome sequences of four Fusarium pseudograminearum isolates, a single Fusarium acuminatum isolate, and an organism from the Fusarium incarnatum-F. equiseti species complex are reported. PMID:24009115

  7. Release of pea germplasm with Fusarium resistance combined with desirable yield and anti-lodging traits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium root rot caused by Fusarium solani f. sp. pisi (Fsp) and Fusarium wilt caused by Fusarium oxysporum f. sp. pisi (Fop) races 1, 2 and 5, negatively impact the pea industry worldwide. Limited pea germplasm with agronomically acceptable characteristics combined with resistance to these disease...

  8. Colonization of Tomato Root by Pathogenic and Nonpathogenic Fusarium oxysporum Strains Inoculated Together and Separately into the Soil

    PubMed Central

    Olivain, Chantal; Humbert, Claude; Nahalkova, Jarmila; Fatehi, Jamshid; L'Haridon, Floriane; Alabouvette, Claude

    2006-01-01

    In soil, fungal colonization of plant roots has been traditionally studied by indirect methods such as microbial isolation that do not enable direct observation of infection sites or of interactions between fungal pathogens and their antagonists. Confocal laser scanning microscopy was used to visualize the colonization of tomato roots in heat-treated soil and to observe the interactions between a nonpathogenic strain, Fo47, and a pathogenic strain, Fol8, inoculated onto tomato roots in soil. When inoculated separately, both fungi colonized the entire root surface, with the exception of the apical zone. When both strains were introduced together, they both colonized the root surface and were observed at the same locations. When Fo47 was introduced at a higher concentration than Fol8, it colonized much of the root surface, but hyphae of Fol8 could still be observed at the same location on the root. There was no exclusion of the pathogenic strain by the presence of the nonpathogenic strain. These results are not consistent with the hypothesis that specific infection sites exist on the root for Fusarium oxysporum and instead support the hypothesis that competition occurs for nutrients rather than for infection sites. PMID:16461707

  9. Biological Efficacy of Streptomyces sp. Strain BN1 against the Cereal Head Blight Pathogen Fusarium graminearum

    PubMed Central

    Jung, Boknam; Park, Sook-Young; Lee, Yin-Won; Lee, Jungkwan

    2013-01-01

    Fusarium head blight (FHB) caused by the filamentous fungus Fusarium graminearum is one of the most severe diseases threatening the production of small grains. Infected grains are often contaminated with mycotoxins such as zearalenone and trichothecences. During survey of contamination by FHB in rice grains, we found a bacterial isolate, designated as BN1, antagonistic to F. graminearum. The strain BN1 had branching vegetative hyphae and spores, and its aerial hyphae often had long, straight filaments bearing spores. The 16S rRNA gene of BN1 had 100% sequence identity with those found in several Streptomyces species. Phylogenetic analysis of ITS regions showed that BN1 grouped with S. sampsonii with 77% bootstrap value, suggesting that BN1 was not a known Streptomyces species. In addition, the efficacy of the BN1 strain against F. graminearum strains was tested both in vitro and in vivo. Wheat seedling length was significantly decreased by F. graminearum infection. However, this effect was mitigated when wheat seeds were treated with BN1 spore suspension prior to F. graminearum infection. BN1 also significantly decreased FHB severity when it was sprayed onto wheat heads, whereas BN1 was not effective when wheat heads were point inoculated. These results suggest that spraying of BN1 spores onto wheat heads during the wheat flowering season can be efficient for plant protection. Mechanistic studies on the antagonistic effect of BN1 against F. graminearum remain to be analyzed. PMID:25288928

  10. Control of Root Rot and Wilt Diseases of Roselle under Field Conditions

    PubMed Central

    Hassan, Naglaa; Elsharkawy, Mohsen Mohamed; Shimizu, Masafumi

    2014-01-01

    Roselle (Hibiscus sabdariffa L.) is one of the most important medicinal crops in many parts of the world. In this study, the effects of microelements, antioxidants, and bioagents on Fusarium oxysporum, F. solani, and Macrophomina phaseolina, the causal pathogens of root rot and wilt diseases in roselle, were examined under field conditions. Preliminary studies were carried out in vitro in order to select the most effective members to be used in field control trials. Our results showed that microelements (copper and manganese), antioxidants (salicylic acid, ascorbic acid, and EDTA), a fungicide (Dithane M45) and biological control agents (Trichoderma harzianum and Bacillus subtilis) were significantly reduced the linear growth of the causal pathogens. Additionally, application of the previous microelements, antioxidants, a fungicide and biological control agents significantly reduced disease incidence of root rot and wilt diseases under field conditions. Copper, salicylic acid, and T. harzianum showed the best results in this respect. In conclusion, microelements, antioxidants, and biocontrol agents could be used as alternative strategies to fungicides for controlling root rot and wilt diseases in roselle. PMID:25606010

  11. Control of Root Rot and Wilt Diseases of Roselle under Field Conditions.

    PubMed

    Hassan, Naglaa; Elsharkawy, Mohsen Mohamed; Shimizu, Masafumi; Hyakumachi, Mitsuro

    2014-12-01

    Roselle (Hibiscus sabdariffa L.) is one of the most important medicinal crops in many parts of the world. In this study, the effects of microelements, antioxidants, and bioagents on Fusarium oxysporum, F. solani, and Macrophomina phaseolina, the causal pathogens of root rot and wilt diseases in roselle, were examined under field conditions. Preliminary studies were carried out in vitro in order to select the most effective members to be used in field control trials. Our results showed that microelements (copper and manganese), antioxidants (salicylic acid, ascorbic acid, and EDTA), a fungicide (Dithane M45) and biological control agents (Trichoderma harzianum and Bacillus subtilis) were significantly reduced the linear growth of the causal pathogens. Additionally, application of the previous microelements, antioxidants, a fungicide and biological control agents significantly reduced disease incidence of root rot and wilt diseases under field conditions. Copper, salicylic acid, and T. harzianum showed the best results in this respect. In conclusion, microelements, antioxidants, and biocontrol agents could be used as alternative strategies to fungicides for controlling root rot and wilt diseases in roselle. PMID:25606010

  12. Plant Disease Lesson: Verticillium wilt

    NSDL National Science Digital Library

    Ingrid Berlanger (Oregon State University; )

    2000-08-01

    This plant disease lesson on Verticillium wilt (caused by Verticillium dahliae) includes information on symptoms and signs, pathogen biology, disease cycle and epidemiology, disease management, and the significance of the disease. Selected references are listed and a glossary is also available for use with this resource.

  13. Arabidopsis defense response against Fusarium oxysporum.

    PubMed

    Berrocal-Lobo, Marta; Molina, Antonio

    2008-03-01

    The plant fungal pathogen Fusarium oxysporum (Fox) is the causal agent of root rot or wilt diseases in several plant species, including crops such as tomato (Solanum lycopersicum), banana (Musa sapientum) and asparagus (Asparagus officinalis). Colonization of plants by Fox leads to the necrosis of the infected tissues, a subsequent collapse of vascular vessels and decay of the plant. Plant resistance to Fox appears to be monogenic or oligogenic depending on the host. Perception of Fox by plants follows the concept of elicitor-induced immune response, which in turn activates several plant defense signaling pathways. Here, we review the Fox-derived elicitors identified so far and the interaction among the different signaling pathways mediating plant resistance to Fox. PMID:18289920

  14. Bronze Wilt of Cotton

    E-print Network

    Bell, Alois A.; Nichols, Robert L.; Lemon, Robert G.

    2002-02-12

    Bronze wilt is a disease of cotton characterized by bronze or red discoloration and wilting of leaves. This publication describes bronze wilt symptoms, the cause and epidemiology of the disease, the varieties in which it has been observed, and ways...

  15. The siderophore-producing bacterium, Bacillus subtilis CAS15, has a biocontrol effect on Fusarium wilt and promotes the growth of pepper

    Microsoft Academic Search

    Xianmei Yu; Chengxiang Ai; Li Xin; Guangfang Zhou

    2011-01-01

    In this study, the Chrome Azurol Sulphonate (CAS) agar plate assay for siderophores was used to screen bacteria from the rhizospheric soil of pepper in Hainan, China. As a result, Bacillus subtilis CAS15, which produced a large orange halo, was obtained. A dual-culture test showed that CAS15 strongly antagonized the growth of 15 plant fungal pathogens, with rates of inhibition

  16. Reliable detection of the fungal pathogen fusarium oxysporum f.sp. albedinis , causal agent of bayoud disease of date palm, using molecular techniques

    Microsoft Academic Search

    Stanley Freeman; Marcel Maymon

    2000-01-01

    Bayoud, caused by the soilborne fungusFusarium oxysporum f.sp.albedinis (FOA), is the most serious disease of date palm. Since the disease is located in the North African countries of Morocco and\\u000a Algeria, and advancing steadily eastwards, the ultimate goal is to prevent spread of the pathogen to other date-growing areas\\u000a in the region and farther afield. Molecular diagnostic techniques have been

  17. Comparative study of the pathogenicity of seabed isolates of Fusarium equiseti and the effect of the composition of the mineral salt medium and temperature on mycelial growth

    PubMed Central

    Palmero, D.; de Cara, M.; Iglesias, C.; Gálvez, L.; Tello, J.C.

    2011-01-01

    The pathogenicity of seven strains of Fusarium equiseti isolated from seabed soil was evaluated on different host plants showing pre and post emergence damage. Radial growth of 27 strains was measured on culture media previously adjusted to different osmotic potentials with either KCl or NaCl (-1.50 to -144.54 bars) at 15°, 25° and 35° C. Significant differences and interactive effects were observed in the response of mycelia to osmotic potential and temperature. PMID:24031710

  18. LDS1-produced oxylipins are negative regulators of growth, conidiation and fumonisin synthesis in the fungal maize pathogen Fusarium verticillioides

    PubMed Central

    Scala, Valeria; Giorni, Paola; Cirlini, Martina; Ludovici, Matteo; Visentin, Ivan; Cardinale, Francesca; Fabbri, Anna A.; Fanelli, Corrado; Reverberi, Massimo; Battilani, Paola; Galaverna, Gianni; Dall'Asta, Chiara

    2014-01-01

    Oxylipins are fatty acid-derived signaling compounds produced by all eukaryotes so far investigated; in mycotoxigenic fungi, they modulate toxin production and interactions with the host plants. Among the many enzymes responsible for oxylipin generation, Linoleate Diol Synthase 1 (LDS1) produces mainly 8-hydroperoxyoctadecenoic acid and subsequently different di-hydroxyoctadecenoic acids. In this study, we inactivated a copy of the putative LDS1 ortholog (acc. N. FVEG_09294.3) of Fusarium verticillioides, with the aim to investigate its influence on the oxylipin profile of the fungus, on its development, secondary metabolism and virulence. LC-MS/MS oxylipin profiling carried out on the selected mutant strain revealed significant quali-quantitative differences for several oxylipins when compared to the WT strain. The Fvlds1-deleted mutant grew better, produced more conidia, synthesized more fumonisins and infected maize cobs faster than the WT strain. We hypothesize that oxylipins may act as regulators of gene expression in the toxigenic plant pathogen F. verticillioides, in turn causing notable changes in its phenotype. These changes could relate to the ability of oxylipins to re-shape the transcriptional profile of F. verticillioides by inducing chromatin modifications and exerting a direct control on the transcription of secondary metabolism in fungi. PMID:25566199

  19. Detoxification of nitric oxide by flavohemoglobin and the denitrification pathway in the maize pathogen Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ephemeral nitric oxide (NO) is a free radical, highly reactive, environmentally rare, and a potent signaling molecule in organisms across kingdoms of life. This gaseous small molecule can freely transverse membranes and has been implicated in aspects of pathogenicity both in animal and plant ho...

  20. First report of Fusarium graminearum, F. asiaticum and F. cortaderiae as head blight pathogens of annual ryegrass in Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Members of the Fusarium graminearum species complex (FGSC) cause Fusarium head blight (FHB) of small grains and several grasses, including annual ryegrass (Lolium multiflorum Lam.), an important forage crop, but also a common weed in wheat, rice and maize agroecosystem in southern Brazil. Although i...

  1. Clonality, recombination, and hybridization in the plumbing-inhabiting human pathogen Fusarium keratoplasticum inferred from multilocus sequence typing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent work has shown that Fusarium species and genotypes most commonly associated with human infections, particularly of the cornea (mycotic keratitis), are the same as those most commonly isolated from plumbing systems. The species most dominant in plumbing biofilms is Fusarium keratoplasticum, a ...

  2. PATHOGENICITY AND IN PLANTA MYCOTOXIN ACCUMULATION AMONG MEMBERS OF THE FUSARIUM GRAMINEARUM SPECIES COMPLEX ON WHEAT AND RICE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight (FHB), or scab, is a destructive disease of small grains caused by members of the Fusarium graminearum (Fg) species complex, comprised of at least nine distinct, cryptic species. Members of this complex are known to produce mycotoxins including the trichothecenes deoxynivalenol ...

  3. Fusarium symbionts of an ambrosia beetle (Euwallacea sp.) in southern Florida are pathogens of avocado, Persea americana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium dieback, a destructive disease of avocado (Persea americana), was reported in California and Israel in 2012. It is associated with an ambrosia beetle, Euwallacea sp., and damage caused by an unnamed symbiont of the beetle in Clade 3 of the Fusarium solani species complex (FSSC) designated p...

  4. Quantitative and Microscopic Assessment of Compatible and Incompatible Interactions between Chickpea Cultivars and Fusarium oxysporum f. sp. ciceris Races

    PubMed Central

    Jiménez-Fernández, Daniel; Landa, Blanca B.; Kang, Seogchan; Jiménez-Díaz, Rafael M.; Navas-Cortés, Juan A.

    2013-01-01

    Background Fusarium wilt caused by Fusarium oxysporum f. sp. ciceris, a main threat to global chickpea production, is managed mainly by resistant cultivars whose efficiency is curtailed by Fusarium oxysporum f. sp. ciceris races. Methodology We characterized compatible and incompatible interactions by assessing the spatial-temporal pattern of infection and colonization of chickpea cvs. P-2245, JG-62 and WR-315 by Fusarium oxysporum f. sp. ciceris races 0 and 5 labeled with ZsGreen fluorescent protein using confocal laser scanning microscopy. Findings The two races colonized the host root surface in both interactions with preferential colonization of the root apex and subapical root zone. In compatible interactions, the pathogen grew intercellularly in the root cortex, reached the xylem, and progressed upwards in the stem xylem, being the rate and intensity of stem colonization directly related with the degree of compatibility among Fusarium oxysporum f. sp. ciceris races and chickpea cultivars. In incompatible interactions, race 0 invaded and colonized ‘JG-62’ xylem vessels of root and stem but in ‘WR-315’, it remained in the intercellular spaces of the root cortex failing to reach the xylem, whereas race 5 progressed up to the hypocotyl. However, all incompatible interactions were asymptomatic. Conclusions The differential patterns of colonization of chickpea cultivars by Fusarium oxysporum f. sp. ciceris races may be related to the operation of multiple resistance mechanisms. PMID:23613839

  5. Loop-Mediated Isothermal Amplification of Specific Endoglucanase Gene Sequence for Detection of the Bacterial Wilt Pathogen Ralstonia solanacearum

    PubMed Central

    Pirc, Manca; Llop, Pablo; Ravnikar, Maja; Dreo, Tanja

    2014-01-01

    The increased globalization of crops production and processing industries also promotes the side-effects of more rapid and efficient spread of plant pathogens. To prevent the associated economic losses, and particularly those related to bacterial diseases where their management relies on removal of the infected material from production, simple, easy-to-perform, rapid and cost-effective tests are needed. Loop-mediated isothermal amplification (LAMP) assays that target 16S rRNA, fliC and egl genes were compared and evaluated as on-site applications. The assay with the best performance was that targeted to the egl gene, which shows high analytical specificity for diverse strains of the betaproteobacterium Ralstonia solanacearum, including its non-European and non-race 3 biovar 2 strains. The additional melting curve analysis provides confirmation of the test results. According to our extensive assessment, the egl LAMP assay requires minimum sample preparation (a few minutes of boiling) for the identification of pure cultures and ooze from symptomatic material, and it can also be used in a high-throughput format in the laboratory. This provides sensitive and reliable detection of R. solanacearum strains of different phylotypes. PMID:24763488

  6. Characterization of the Maize Stalk Rot Pathogens Fusarium subglutinans and F. temperatum and the Effect of Fungicides on Their Mycelial Growth and Colony Formation

    PubMed Central

    Shin, Jong-Hwan; Han, Joon-Hee; Lee, Ju Kyong; Kim, Kyoung Su

    2014-01-01

    Maize is a socioeconomically important crop in many countries. Recently, a high incidence of stalk rot disease has been reported in several maize fields in Gangwon province. In this report, we show that maize stalk rot is associated with the fungal pathogens Fusarium subglutinans and F. temperatum. Since no fungicides are available to control these pathogens on maize plants, we selected six fungicides (tebuconazole, difenoconazole, fluquinconazole, azoxystrobin, prochloraz and kresoxim-methyl) and examined their effectiveness against the two pathogens. The in vitro antifungal effects of the six fungicides on mycelial growth and colony formation were investigated. Based on the inhibition of mycelial growth, the most toxic fungicide was tebuconazole with 50% effective concentrations (EC50) of <0.1 ?g/ml and EC90 values of 0.9 ?g/ml for both pathogens, while the least toxic fungicide was azoxystrobin with EC50 values of 0.7 and 0.5 ?g/ml for F. subglutinans and F. temperatum, respectively, and EC90 values of >3,000 ?g/ml for both pathogens. Based on the inhibition of colony formation by the two pathogens, kresoxim-methyl was the most toxic fungicide with complete inhibition of colony formation at concentrations of 0.1 and 0.01 ?g/ml for F. subglutinans and F. temperatum, respectively, whereas azoxystrobin was the least toxic fungicide with complete inhibition of colony formation at concentrations >3,000 ?g/ml for both pathogens. PMID:25506304

  7. Dry heat treatment of Fusarium-infected cotton seed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt caused by Fusarium oxysporum f. sp. vasinfectum (FOV) race 4 has emerged as the dominant disease concern for cotton growers in California. Originally described from Asia, race 4 has spread into multiple counties in the San Joaquin Valley (SJV) since its discovery in one California fiel...

  8. Fusarium oxysporum f. sp. vasinfectum race 4 in California

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A brief review of research on Fusarium oxysporum Schlechtend.:Fr. f. sp. vasinfectum (Atk.) W.C. Snyder & H.N. Hans. race 4 in California is presented. Fusarium wilt has recently emerged as the dominant disease concern for cotton (Gossypium hirsutum L., G. barbadense L.) growers in California. An es...

  9. Fusarium Race 4: Commercial cultivar screening for resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt (FOV) of cotton in California has been considered a potentially serious fungal disease for many decades in areas of the San Joaquin Valley (SJV). In the past, damage from Fusarium has been notable only in areas with the combination of: (a) moderate to high populations of one or more sp...

  10. Molecular Characterization of MADS-BOX Transcription Factors and Analysis of Field Population Diversity in the Maize Pathogen Fusarium verticillioides

    E-print Network

    Ortiz, Carlos S

    2013-04-10

    Fusarium verticillioides (Teleomorph Giberella moniliformis) is an ascomycete fungus responsible for ear and stalk rots of maize. Most importantly, it produces a group of mycotoxins called fumonisins upon colonization of maize kernels. Fumonisin B1...

  11. High Genetic Diversity Among Strains of Fusarium oxysporum f. sp. vasinfectum from Cotton in Ivory Coast.

    PubMed

    Abo, Kouabenan; Klein, Keith K; Edel-Hermann, Véronique; Gautheron, Nadine; Traore, Dossahoua; Steinberg, Christian

    2005-12-01

    ABSTRACT Seventeen isolates of Fusarium oxysporum f. sp. vasinfectum from the Ivory Coast were characterized using vegetative compatibility group (VCG), restriction fragment length polymorphism of the ribosomal inter-genic spacer region (IGS), and mating type (MAT) idiomorph, and compared with a worldwide collection of the pathogen containing all available reference strains. Some of the isolates were identical to known reference strains for all three traits, whereas others had previously unknown varieties of IGS and (possibly) VCG. One or the other MAT idiomorph was present in each of the new isolates and the reference strains. The new isolates and reference strains were grouped based upon the three traits. Strains from the Ivory Coast were found in 7 of 11 groups detected, suggesting multiple sources for Fusarium wilt in the country. Despite the presence of both MAT idiomorphs among isolates, no evidence for recombination was found. PMID:18943549

  12. Fot 1 insertions in the Fusarium oxysporum f. sp. albedinis genome provide diagnostic PCR targets for detection of the date palm pathogen.

    PubMed

    Fernandez, D; Ouinten, M; Tantaoui, A; Geiger, J P; Daboussi, M J; Langin, T

    1998-02-01

    Populations of Fusarium oxysporum f. sp. albedinis, the causal agent of Bayoud disease of date palm, are derivatives of a single clonal lineage and exhibit very similar Fot 1 hybridization patterns. In order to develop a sensitive diagnostic tool for F. oxysporum f. sp. albedinis detection, we isolated several DNA clones containing a copy of the transposable element Fot 1 from a genomic library of the date palm pathogen. Regions flanking the insertion sites were sequenced, and these sequences were used to design PCR primers that amplify the DNA regions at several Fot 1 insertion sites. When tested on a large sample of Fusarium isolates, including 286 F. oxysporum f. sp. albedinis isolates, 17 other special forms, nonpathogenic F. oxysporum isolates from palm grove soils, and 8 other Fusarium species, the primer pair TL3-FOA28 allowed amplification of a 400-bp fragment found only in F. oxysporum f. sp. albedinis. Sequence analysis showed that one of the Fot 1 copies was truncated, lacking 182 bp at its 3' terminus. The primer pair BI03-FOA1 amplified a 204-bp fragment which overlapped the Fot 1 truncated copy and its 3' site of insertion in the F. oxysporum f. sp. albedinis genome and identified 95% of the isolates. The primer pairs BIO3-FOA1 and TL3-FOA28 used in PCR assays thus provide a useful diagnostic tool for F. oxysporum f. sp. albedinis isolates. PMID:9464402

  13. Fot 1 Insertions in the Fusarium oxysporum f. sp. albedinis Genome Provide Diagnostic PCR Targets for Detection of the Date Palm Pathogen

    PubMed Central

    Fernandez, Diana; Ouinten, Mohamed; Tantaoui, Abdelaziz; Geiger, Jean-Paul; Daboussi, Marie-Josée; Langin, Thierry

    1998-01-01

    Populations of Fusarium oxysporum f. sp. albedinis, the causal agent of Bayoud disease of date palm, are derivatives of a single clonal lineage and exhibit very similar Fot 1 hybridization patterns. In order to develop a sensitive diagnostic tool for F. oxysporum f. sp. albedinis detection, we isolated several DNA clones containing a copy of the transposable element Fot 1 from a genomic library of the date palm pathogen. Regions flanking the insertion sites were sequenced, and these sequences were used to design PCR primers that amplify the DNA regions at several Fot 1 insertion sites. When tested on a large sample of Fusarium isolates, including 286 F. oxysporum f. sp. albedinis isolates, 17 other special forms, nonpathogenic F. oxysporum isolates from palm grove soils, and 8 other Fusarium species, the primer pair TL3-FOA28 allowed amplification of a 400-bp fragment found only in F. oxysporum f. sp. albedinis. Sequence analysis showed that one of the Fot 1 copies was truncated, lacking 182 bp at its 3? terminus. The primer pair BI03-FOA1 amplified a 204-bp fragment which overlapped the Fot 1 truncated copy and its 3? site of insertion in the F. oxysporum f. sp. albedinis genome and identified 95% of the isolates. The primer pairs BIO3-FOA1 and TL3-FOA28 used in PCR assays thus provide a useful diagnostic tool for F. oxysporum f. sp. albedinis isolates. PMID:9464402

  14. Enhanced Control of Cucumber Wilt Disease by Bacillus amyloliquefaciens SQR9 by Altering the Regulation of Its DegU Phosphorylation

    PubMed Central

    Xu, Zhihui; Zhang, Ruifu; Wang, Dandan; Qiu, Meihua; Feng, Haichao; Zhang, Nan

    2014-01-01

    Bacillus amyloliquefaciens strain SQR9, isolated from the cucumber rhizosphere, suppresses the growth of Fusarium oxysporum in the cucumber rhizosphere and protects the host plant from pathogen invasion through efficient root colonization. In the Gram-positive bacterium Bacillus, the response regulator DegU regulates genetic competence, swarming motility, biofilm formation, complex colony architecture, and protease production. In this study, we report that stepwise phosphorylation of DegU in B. amyloliquefaciens SQR9 can influence biocontrol activity by coordinating multicellular behavior and regulating the synthesis of antibiotics. Results from in vitro and in situ experiments and quantitative PCR (qPCR) studies demonstrate the following: (i) that the lowest level of phosphorylated DegU (DegU?P) (the degQ mutation) impairs complex colony architecture, biofilm formation, colonization activities, and biocontrol efficiency of Fusarium wilt disease but increases the production of macrolactin and bacillaene, and (ii) that increasing the level of DegU?P by degQ and degSU overexpression significantly improves complex colony architecture, biofilm formation, colonization activities, production of the antibiotics bacillomycin D and difficidin, and efficiency of biocontrol of Fusarium wilt disease. The results offer a new strategy to enhance the biocontrol efficacy of Bacillus amyloliquefaciens SQR9. PMID:24584252

  15. Antimicrobial activities of Streptomyces pulcher, S. canescens and S. citreofluorescens against fungal and bacterial pathogens of tomato in vitro.

    PubMed

    el-Abyad, M S; el-Sayed, M A; el-Shanshoury, A R; el-Sabbagh, S M

    1996-01-01

    Thirty-seven actinomycete species isolated from fertile cultivated soils in Egypt were screened for the production of antimicrobial compounds against a variety of test organisms. Most of the isolates exhibited antimicrobial activities against Gram-positive, Gram-negative, and acid-fast bacteria, yeasts and filamentous fungi, with special attention to fungal and bacterial pathogens of tomato. On starch-nitrate agar, 14 strains were active against Fusarium oxysporum f.sp. lycopersici (the cause of Fusarium wilt), 18 against Verticillium albo-atrum (the cause of Verticillium wilt), and 18 against Alternaria solani (the cause of early blight). In liquid media, 14 isolates antagonized Pseudomonas solanacearum (the cause of bacterial wilt) and 20 antagonized Clavibacter michiganensis ssp. michiganensis (the cause of bacterial canker). The most active antagonists of the pathogenic microorganisms studied were found to be Streptomyces pulcher, S. canescens (syn. S. albidoflavus) and S. citreofluorescens (syn. S. anulatus). The antagonistic activities of S. pulcher and S. canescens against pathogenic fungi were assessed on solid media, and those of S. pulcher and S. citreofluorescens against pathogenic bacteria in liquid media under shaking conditions. The optimum culture conditions were determined. PMID:9131789

  16. Contamination of Bananas with Beauvericin and Fusaric Acid Produced by Fusarium oxysporum f. sp. cubense

    PubMed Central

    Kuang, Ruibin; Yang, Qiaosong; Hu, Chunhua; Sheng, Ou; Zhang, Sheng; Ma, Lijun; Wei, Yuerong; Yang, Jing; Liu, Siwen; Biswas, Manosh Kumar; Viljoen, Altus; Yi, Ganjun

    2013-01-01

    Background Fusarium wilt, caused by the fungal pathogen Fusarium oxysporum f. sp. cubense (Foc), is one of the most destructive diseases of banana. Toxins produced by Foc have been proposed to play an important role during the pathogenic process. The objectives of this study were to investigate the contamination of banana with toxins produced by Foc, and to elucidate their role in pathogenesis. Methodology/Principal Findings Twenty isolates of Foc representing races 1 and 4 were isolated from diseased bananas in five Chinese provinces. Two toxins were consistently associated with Foc, fusaric acid (FA) and beauvericin (BEA). Cytotoxicity of the two toxins on banana protoplast was determined using the Alamar Blue assay. The virulence of 20 Foc isolates was further tested by inoculating tissue culture banana plantlets, and the contents of toxins determined in banana roots, pseudostems and leaves. Virulence of Foc isolates correlated well with toxin deposition in the host plant. To determine the natural occurrence of the two toxins in banana plants with Fusarium wilt symptoms, samples were collected before harvest from the pseudostems, fruit and leaves from 10 Pisang Awak ‘Guangfen #1’ and 10 Cavendish ‘Brazilian’ plants. Fusaric acid and BEA were detected in all the tissues, including the fruits. Conclusions/Signficance The current study provides the first investigation of toxins produced by Foc in banana. The toxins produced by Foc, and their levels of contamination of banana fruits, however, were too low to be of concern to human and animal health. Rather, these toxins appear to contribute to the pathogenicity of the fungus during infection of banana plants. PMID:23922960

  17. Fusarial wilt control and growth promotion of pigeon pea through bioactive metabolites produced by two plant growth promoting rhizobacteria.

    PubMed

    Dutta, S; Morang, P; Nishanth Kumar, S; Dileep Kumar, B S

    2014-03-01

    The bioactive metabolites produced by two plant growth promoting rhizobacteria strains, a Pseudomonas aeruginosa strain RRLJ 04 and a Bacillus cereus strain BS 03, which showed growth promotion and disease control in pigeon pea against Fusarium udum, were isolated and screened for their efficacy to control fusarial wilt of pigeon pea under gnotobiotic and nursery condition. Bioactive metabolites viz., BM 1 and BM 2 from RRLJ 04 and BM 3 from BS 03 also showed in vitro antibiosis against F. udum. Seeds treated with 50 ?l seed?¹ of BM 1, 30 ?l seed?¹ of BM 2 and 70 ?l seed?¹ of BM 3 and grown in pathogen infested soil showed suppression of wilt disease besides growth enhancement. Per cent disease control was 90 % with BM 2 application as compared to 87 and 83 %, respectively in BM 1 and BM 3 after 90 days of growth. BM 2 treated plants were more resistant to the pathogen as compared to the other fractions tested. Mycelial dry weight was found to be reduced on treatment with the bioactive metabolites. Formation of chlamydospore-like structures was observed in the pathogen mycelium treated with BM 3. The analytical studies confirmed that two of these metabolites are phenazine derivatives. PMID:24154979

  18. Fusarium graminearum Isolates from Wheat and Maize in New York Show Similar Range of Aggressiveness and Toxigenicity in Cross-Species Pathogenicity Tests.

    PubMed

    Kuhnem, Paulo R; Del Ponte, Emerson M; Dong, Yanhong; Bergstrom, Gary C

    2015-04-01

    This study aimed to assess whether pathogenic Fusarium graminearum isolates from wheat and maize were more aggressive on their host of origin and whether aggressiveness was influenced further by B-trichothecene chemotype. Fifteen isolates were selected from a contemporary collection of isolates surveyed in New York in 2011 to 2012 to represent diversity of host of origin and chemotype. Three pathogenicity assays were used to evaluate and compare these isolates. Fusarium head blight (FHB) severity and trichothecene production in wheat, and maize seedling blight were evaluated in greenhouse inoculation experiments, and Gibberella ear rot (GER) severity and trichothecene production were evaluated in maize ears inoculated in the field. Our results showed among F. graminearum isolates a wide variation in aggressiveness and mycotoxin production toward wheat and maize and these isolates could not be structured by their host of origin or by chemotype. Moreover, aggressiveness rank order changed according to the host/organ evaluated. This indicates that relative susceptibility at the seedling stage may not predict susceptibility of ears. Significant correlations were observed of total trichothecenes (deoxynivalenol [DON] and its acetylated derivatives) produced with FHB and GER severity on wheat and maize, respectively. One isolate did not produce DON or ADON in wheat or maize kernels, yet was aggressive on both hosts. Nine of the fifteen isolates produced small amounts of zearalenone (ZON) in maize kernels, but not in wheat kernels, and ZON level was not correlated with GER severity. F. graminearum isolates from New York showed wide variation in aggressiveness and mycotoxin production toward susceptible wheat and maize. Neither host of origin nor trichothecene chemotype appeared to structure the populations we sampled. PMID:25338173

  19. Tomatidine and lycotetraose, hydrolysis products of alpha-tomatine by Fusarium oxysporum tomatinase, suppress induced defense responses in tomato cells.

    PubMed

    Ito, Shin-ichi; Eto, Tomomi; Tanaka, Shuhei; Yamauchi, Naoki; Takahara, Hiroyuki; Ikeda, Tsuyoshi

    2004-07-30

    Many fungal pathogens of tomato produce extracellular enzymes, collectively known as tomatinases, that detoxify the preformed antifungal steroidal glycoalkaloid alpha-tomatine. Tomatinase from the vascular wilt pathogen of tomato Fusarium oxysporum f. sp. lycopersici cleaves alpha-tomatine into the aglycon tomatidine (Td) and the tetrasaccharide lycotetraose (Lt). Although modes of action of alpha-tomatine have been extensively studied, those of Td and Lt are poorly understood. Here, we show that both Td and Lt inhibit the oxidative burst and hypersensitive cell death in suspension-cultured tomato cells. A tomatinase-negative F. oxysporum strain inherently non-pathogenic on tomato was able to infect tomato cuttings when either Td or Lt was present. These results suggest that tomatinase from F. oxysporum is required not only for detoxification of alpha-tomatine but also for suppression of induced defense responses of host. PMID:15280013

  20. Banana infecting fungus, Fusarium musae, is also an opportunistic human pathogen: are bananas potential carriers and source of fusariosis?

    PubMed

    Triest, David; Stubbe, Dirk; De Cremer, Koen; Piérard, Denis; Detandt, Monique; Hendrickx, Marijke

    2015-01-01

    During re-identification of Fusarium strains in the BCCM™/IHEM fungal collection by multilocus sequence-analysis we observed that five strains, previously identified as Fusarium verticillioides, were Fusarium musae, a species described in 2011 from banana fruits. Four strains were isolated from blood samples or biopsies of immune-suppressed patients and one was isolated from the clinical environment, all originating from different hospitals in Belgium or France, 2001-2008. The F. musae identity of our isolates was confirmed by phylogenetic analysis using reference sequences of type material. Absence of the gene cluster necessary for fumonisin biosynthesis, characteristic to F. musae, was also the case for our isolates. In vitro antifungal susceptibility testing revealed no important differences in their susceptibility compared to clinical F. verticillioides strains and terbinafine was the most effective drug. Additional clinical F. musae strains were searched by performing BLAST queries in GenBank. Eight strains were found, of which six were keratitis cases from the U.S. multistate contact lens-associated outbreak in 2005 and 2006. The two other strains were also from the U.S., causing either a skin infection or sinusitis. This report is the first to describe F. musae as causative agent of superficial and opportunistic, disseminated infections in humans. Imported bananas might act as carriers of F. musae spores and be a potential source of infection with F. musae in humans. An alternative hypothesis is that the natural distribution of F. musae is geographically a lot broader than originally suspected and F. musae is present on different plant hosts. PMID:25361833

  1. The adenylyl cyclase plays a regulatory role in the morphogenetic switch from vegetative to pathogenic lifestyle of Fusarium graminearum on wheat.

    PubMed

    Bormann, Jörg; Boenisch, Marike Johanne; Brückner, Elena; Firat, Demet; Schäfer, Wilhelm

    2014-01-01

    Cyclic 3',5'-adenosine monophosphate (cAMP) is a nucleotide derived from adenosine triphosphate that acts as a second messenger throughout all kingdoms. Intracellular cAMP levels are synthesized by a membrane-bound protein, the adenylyl cyclase. In order to analyze the function of this gene and the importance of cAMP in the life cycle of the cereal pathogen Fusarium graminearum, the adenylyl cyclase gene (FGSG_01234) was deleted by gene replacement (?Fgac1). The ?Fgac1 mutant displayed a drastically reduced growth on agar medium which could be rescued by a cAMP analogon. Furthermore, the ?Fgac1 mutant was unable to produce perithecia on detached wheat nodes. However, artificial conditions like carrot agar allowed perithecia development. Pathogenicity towards wheat was drastically reduced in ?Fgac1 compared to the wild type. Point-inoculated spikelets showed only small lesions but no typical head blight disease symptoms. Fluorescence microscopy using dsRed-expressing strains revealed that the ?Fgac1 strain was unable to develop any complex infection structures like lobate appressoria and infection cushions. Instead, hyphal anastomosis occurs frequently. Scanning electron microscopy demonstrated the lack of fungal penetration. Hence, the formation of compound appressoria seems to be essential for infection of wheat. Hyphae on flower leaves produced huge amounts of new conidia, thereby circumventing the infection cycle. This abundant sporulation on wheat epidermis was not observed in wild type. Intriguingly, the Fgac1 deletion mutant was able to infect maize cobs as wild type, indicating that cAMP signaling is not important for maize infection. The ?Fgac1 mutant was unable to produce the mycotoxin deoxynivalenol both in vitro and during wheat infection. In this study, we show that cAMP signaling controls important cellular processes such as development of infection structures, pathogenicity, secondary metabolite production and sexual reproduction. For the first time, we show that cAMP regulates the switch from vegetative to pathogenic lifestyle of F. graminearum on wheat. PMID:24603887

  2. The Adenylyl Cyclase Plays a Regulatory Role in the Morphogenetic Switch from Vegetative to Pathogenic Lifestyle of Fusarium graminearum on Wheat

    PubMed Central

    Bormann, Jörg; Boenisch, Marike Johanne; Brückner, Elena; Firat, Demet; Schäfer, Wilhelm

    2014-01-01

    Cyclic 3?,5?-adenosine monophosphate (cAMP) is a nucleotide derived from adenosine triphosphate that acts as a second messenger throughout all kingdoms. Intracellular cAMP levels are synthesized by a membrane-bound protein, the adenylyl cyclase. In order to analyze the function of this gene and the importance of cAMP in the life cycle of the cereal pathogen Fusarium graminearum, the adenylyl cyclase gene (FGSG_01234) was deleted by gene replacement (?Fgac1). The ?Fgac1 mutant displayed a drastically reduced growth on agar medium which could be rescued by a cAMP analogon. Furthermore, the ?Fgac1 mutant was unable to produce perithecia on detached wheat nodes. However, artificial conditions like carrot agar allowed perithecia development. Pathogenicity towards wheat was drastically reduced in ?Fgac1 compared to the wild type. Point-inoculated spikelets showed only small lesions but no typical head blight disease symptoms. Fluorescence microscopy using dsRed-expressing strains revealed that the ?Fgac1 strain was unable to develop any complex infection structures like lobate appressoria and infection cushions. Instead, hyphal anastomosis occurs frequently. Scanning electron microscopy demonstrated the lack of fungal penetration. Hence, the formation of compound appressoria seems to be essential for infection of wheat. Hyphae on flower leaves produced huge amounts of new conidia, thereby circumventing the infection cycle. This abundant sporulation on wheat epidermis was not observed in wild type. Intriguingly, the Fgac1 deletion mutant was able to infect maize cobs as wild type, indicating that cAMP signaling is not important for maize infection. The ?Fgac1 mutant was unable to produce the mycotoxin deoxynivalenol both in vitro and during wheat infection. In this study, we show that cAMP signaling controls important cellular processes such as development of infection structures, pathogenicity, secondary metabolite production and sexual reproduction. For the first time, we show that cAMP regulates the switch from vegetative to pathogenic lifestyle of F. graminearum on wheat. PMID:24603887

  3. The global regulator FfSge1 is required for expression of secondary metabolite gene clusters but not for pathogenicity in Fusarium fujikuroi.

    PubMed

    Michielse, Caroline B; Studt, Lena; Janevska, Slavica; Sieber, Christian M K; Arndt, Birgit; Espino, Jose Juan; Humpf, Hans-Ulrich; Güldener, Ulrich; Tudzynski, Bettina

    2014-08-12

    The plant pathogenic fungus Fusarium fujikuroi is the causal agent of bakanae disease on rice due to its ability to produce gibberellins. Besides these phytohormones, F.?fujikuroi is able to produce several other secondary metabolites (SMs). Although much progress has been made in the field of secondary metabolism, the transcriptional regulation of SM biosynthesis is complex and still incompletely understood. Environmental conditions, global as well as pathway-specific regulators and chromatin remodelling have been shown to play major roles. Here, the role of FfSge1, a homologue of the morphological switch regulators Wor1 and Ryp1 in Candida albicans and Histoplasma capsulatum, respectively, is explored with emphasis on secondary metabolism. FfSge1 is not required for formation of conidia and pathogenicity but is involved in vegetative growth. Transcriptome analysis of the mutant ?ffsge1 compared with the wild type, as well as comparative chemical analysis between the wild type, ?ffsge1 and OE:FfSGE1, revealed that FfSge1 functions as a global activator of secondary metabolism in F.?fujikuroi. Double mutants of FfSGE1 and other SM regulatory genes brought insights into the hierarchical regulation of secondary metabolism. In addition, FfSge1 is also required for expression of a yet uncharacterized SM gene cluster containing a non-canonical non-ribosomal peptide synthetase. PMID:25115968

  4. Deciphering the cryptic genome: genome-wide analyses of the rice pathogen Fusarium fujikuroi reveal complex regulation of secondary metabolism and novel metabolites.

    PubMed

    Wiemann, Philipp; Sieber, Christian M K; von Bargen, Katharina W; Studt, Lena; Niehaus, Eva-Maria; Espino, Jose J; Huß, Kathleen; Michielse, Caroline B; Albermann, Sabine; Wagner, Dominik; Bergner, Sonja V; Connolly, Lanelle R; Fischer, Andreas; Reuter, Gunter; Kleigrewe, Karin; Bald, Till; Wingfield, Brenda D; Ophir, Ron; Freeman, Stanley; Hippler, Michael; Smith, Kristina M; Brown, Daren W; Proctor, Robert H; Münsterkötter, Martin; Freitag, Michael; Humpf, Hans-Ulrich; Güldener, Ulrich; Tudzynski, Bettina

    2013-01-01

    The fungus Fusarium fujikuroi causes "bakanae" disease of rice due to its ability to produce gibberellins (GAs), but it is also known for producing harmful mycotoxins. However, the genetic capacity for the whole arsenal of natural compounds and their role in the fungus' interaction with rice remained unknown. Here, we present a high-quality genome sequence of F. fujikuroi that was assembled into 12 scaffolds corresponding to the 12 chromosomes described for the fungus. We used the genome sequence along with ChIP-seq, transcriptome, proteome, and HPLC-FTMS-based metabolome analyses to identify the potential secondary metabolite biosynthetic gene clusters and to examine their regulation in response to nitrogen availability and plant signals. The results indicate that expression of most but not all gene clusters correlate with proteome and ChIP-seq data. Comparison of the F. fujikuroi genome to those of six other fusaria revealed that only a small number of gene clusters are conserved among these species, thus providing new insights into the divergence of secondary metabolism in the genus Fusarium. Noteworthy, GA biosynthetic genes are present in some related species, but GA biosynthesis is limited to F. fujikuroi, suggesting that this provides a selective advantage during infection of the preferred host plant rice. Among the genome sequences analyzed, one cluster that includes a polyketide synthase gene (PKS19) and another that includes a non-ribosomal peptide synthetase gene (NRPS31) are unique to F. fujikuroi. The metabolites derived from these clusters were identified by HPLC-FTMS-based analyses of engineered F. fujikuroi strains overexpressing cluster genes. In planta expression studies suggest a specific role for the PKS19-derived product during rice infection. Thus, our results indicate that combined comparative genomics and genome-wide experimental analyses identified novel genes and secondary metabolites that contribute to the evolutionary success of F. fujikuroi as a rice pathogen. PMID:23825955

  5. Observations on the effect of lower-temperature dry heat treatments on Fusarium in cotton seed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt caused by Fusarium oxysporum f. sp. vasinfectum (FOV) race 4 has emerged as the dominant disease concern for cotton growers in California. Originally described from Asia, race 4 has spread into multiple counties in the San Joaquin Valley (SJV) since its discovery in one California fiel...

  6. New genotypes of Fusarium oxysporum f. sp. vasinfectum from the Southeastern United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sixty-one isolates of Fusarium oxysporum f. sp. vasinfectum were collected from cotton plants (Gossypium spp.) with symptoms of Fusarium wilt to determine the composition of races present in the southeastern U.S. Analysis of partial sequences of the translation elongation factor gene revealed four n...

  7. Update of Commercial Cultivar Screening for Resistance to Race 4 Fusarium oxysporum vasinfectum.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt impacts on cotton in the San Joaquin Valley of California focused mostly on race 1 Fusarium oxysporum vasinfectum (FOV), with most economic impacts occurring when the disease was present in association with nematode damage. During the past five years, field investigations have found Fu...

  8. Clonality, recombination, and hybridization in the plumbing-inhabiting human pathogen Fusarium keratoplasticum inferred from multilocus sequence typing

    PubMed Central

    2014-01-01

    Background Recent work has shown that Fusarium species and genotypes most commonly associated with human infections, particularly of the cornea (mycotic keratitis), are the same as those most commonly isolated from plumbing systems. The species most dominant in plumbing biofilms is Fusarium keratoplasticum, a cosmopolitan fungus known almost exclusively from animal infections and biofilms. To better understand its diversity and population dynamics, we developed and utilized a nine-locus sequence-based typing system to make inferences about clonality, recombination, population structure, species boundaries and hybridization. Results High levels of genetic diversity and evidence for recombination and clonality were detected among 75 clinical and 156 environmental isolates of Fusarium keratoplasticum. The multilocus sequence typing system (MLST) resolved 111 unique nine-locus sequence types (STs). The single locus bifactorial determinants of mating compatibility (mating types MAT1-1 and MAT1-2), were found in a ratio of 70:30. All but one of the 49 isolates of the most common ST (FSSC 2d-2) came from human infections, mostly of the cornea, and from biofilms associated with contact lenses and plumbing surfaces. Significant levels of phylogenetic incongruence were found among loci. Putative clonal relationships among genotypes were estimated, showing a mixture of large clonal complexes and unrelated singletons. Discordance between the nuclear ribosomal rRNA and other gene genealogies is consistent with introgression of ribosomal RNA alleles of phylogenetic species FSSC 9 into F. keratoplasticum. No significant population subdivision based on clinical versus non-clinical sources was found. Conclusions Incongruent phylogenetic trees and the presence of both mating types within otherwise identical STs were observed, providing evidence for sexuality in F. keratoplasticum. Cryptic speciation suggested in a published three-locus MLST system was not supported with the addition of new loci, but evidence of introgression of ribosomal RNA genes from another strongly supported phylogenetic species (FSSC 9), also known from plumbing systems and human infections, was detected in two isolates. Overall, F. keratoplasticum is a diverse and geographically unstructured species with a mixed clonal and recombinant life history. PMID:24766947

  9. Interactions of concomitant species of nematodes and Fusarium oxysporum f. sp. vasinfectum on cotton.

    PubMed

    Yang, H; Powell, N T; Barker, K R

    1976-01-01

    Meloidogyne incognita, Hoplolaintus galeatus, and North Carolina and Georgia populations of Belonolaimus longicaudatus were introduced singly and in various combinations with Fusarium oxysporum f. sp. vasinfectum on wilt-susceptible 'Rowden' cotton. Of all the nematodes, the combination of the N. C. population of B. longicaudatus with Fusarium promoted greatest wilt development. H. galeatus had no effect on wilt. With Fusarium plus M. incognito or B. longicaudatus, high nematode levels promoted greater wilt than low levels. The combination of either population of B. longicaudatus with M. incognita and Fusarium induced greater wilt development than comparable inoculum densities of either nematode alone or where H. galeatus was substituted for either of these nematodes. Nematode reproduction was inversely related to wilt development. Without Fusarium, however, the high inoculum level resulted in greater reproduction of all nematode species on cotton. Combining M. incognita with B. longicaudatus or H. galeatus gave mutually depressive effects on final nematode populations. The interactions of H. gateatus with B. longicaudatus varied with two populations of the latter. PMID:19308201

  10. Genetic Diversity of Fusarium oxysporum Strains from Common Bean Fields in Spain

    PubMed Central

    Alves-Santos, Fernando M.; Benito, Ernesto P.; Eslava, Arturo P.; Díaz-Mínguez, José María

    1999-01-01

    Fusarium wilt is an endemic disease in El Barco de Avila (Castilla y León, west-central Spain), where high-quality common bean cultivars have been cultured for the last century. We used intergenic spacer (IGS) region polymorphism of ribosomal DNA, electrophoretic karyotype patterns, and vegetative compatibility and pathogenicity analyses to assess the genetic diversity within Fusarium oxysporum isolates recovered from common bean plants growing in fields around El Barco de Avila. Ninety-six vegetative compatibility groups (VCGs) were found among 128 isolates analyzed; most of these VCGs contained only a single isolate. The strains belonging to pathogenic VCGs and the most abundant nonpathogenic VCGs were further examined for polymorphisms in the IGS region and electrophoretic karyotype patterns. Isolates belonging to the same VCG exhibited the same IGS haplotype and very similar electrophoretic karyotype patterns. These findings are consistent with the hypothesis that VCGs represent clonal lineages that rarely, if ever, reproduce sexually. The F. oxysporum f. sp. phaseoli strains recovered had the same IGS haplotype and similar electrophoretic karyotype patterns, different from those found for F. oxysporum f. sp. phaseoli from the Americas, and were assigned to three new VCGs (VCGs 0166, 0167, and 0168). Based on our results, we do not consider the strains belonging to F. oxysporum f. sp. phaseoli to be a monophyletic group within F. oxysporum, as there is no correlation between pathogenicity and VCG, IGS restriction fragment length polymorphism, or electrophoretic karyotype. PMID:10427016

  11. Candidate genes associated with QTL controlling resistance to fusarium root rot in pea

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium root rot (FRR) of pea (Pisum sativum L.) is a serious pathogen in the USA and Europe and genetic resistance offers an effective and economical control for this pathogen. Fusarium root rot is caused by the fungus pathogen (Haematonectria haematococca (Berk. & Broome) (Anamorph): Fusarium sol...

  12. Interaction of Population Levels of Fusarium oxysporum f. sp. vasinfectum and Meloidogyne incognita on Cotton.

    PubMed

    Garber, R H; Jorgenson, E C; Smith, S; Hyer, A H

    1979-04-01

    In autoclaved greenhouse soil without Fusarium oxysporum f. sp. vasinfectum, Meloidogyne incognita did not cause leaf or vascular discoloration of 59-day-old cotton plants. Plants had root galls with as few as 50 Meloidogyne larvae per plant. Root galling was directly proportional to the initial nematode population level. Fusarium wilt symptoms occurred without nematodes with 77,000 fungus propagules or more per gram of soil. As few as 50 Meloidogyne larvae accompanying 650 fungus propagules caused Fusarium wilt. With few exceptions, leaf symptoms appeared sooner as numbers of either or both organisms increased. In soils infested with both organisms, the extent of fungal invasion and colonization was well correlated with the extent of nematode galling and other indications of the Fusarium wilt syndrome. PMID:19305546

  13. Mitogen-Activated Protein Kinases Are Associated with the Regulation of Physiological Traits and Virulence in Fusarium oxysporum f. sp. cubense

    PubMed Central

    Ding, Zhaojian; Li, Minhui; Sun, Fei; Xi, Pinggen; Sun, Longhua; Zhang, Lianhui; Jiang, Zide

    2015-01-01

    Fusarium oxysporum f. sp. cubense (FOC) is an important soil-borne fungal pathogen causing devastating vascular wilt disease of banana plants and has become a great concern threatening banana production worldwide. However, little information is known about the molecular mechanisms that govern the expression of virulence determinants of this important fungal pathogen. In this study, we showed that null mutation of three mitogen-activated protein (MAP) kinase genes, designated as FoSlt2, FoMkk2 and FoBck1, respectively, led to substantial attenuation in fungal virulence on banana plants. Transcriptional analysis revealed that the MAP kinase signaling pathway plays a key role in regulation of the genes encoding production of chitin, peroxidase, beauvericin and fusaric acid. Biochemical analysis further confirmed the essential role of MAP kinases in modulating the production of fusaric acid, which was a crucial phytotoxin in accelerating development of Fusarium wilt symptoms in banana plants. Additionally, we found that the MAP kinase FoSlt2 was required for siderophore biosynthesis under iron-depletion conditions. Moreover, disruption of the MAP kinase genes resulted in abnormal hypha and increased sensitivity to Congo Red, Calcofluor White and H2O2. Taken together, these results depict the critical roles of MAP kinases in regulation of FOC physiology and virulence. PMID:25849862

  14. The Genome of the Generalist Plant Pathogen Fusarium avenaceum Is Enriched with Genes Involved in Redox, Signaling and Secondary Metabolism

    PubMed Central

    Lysøe, Erik; Harris, Linda J.; Walkowiak, Sean; Subramaniam, Rajagopal; Divon, Hege H.; Riiser, Even S.; Llorens, Carlos; Gabaldón, Toni; Kistler, H. Corby; Jonkers, Wilfried; Kolseth, Anna-Karin; Nielsen, Kristian F.; Thrane, Ulf; Frandsen, Rasmus J. N.

    2014-01-01

    Fusarium avenaceum is a fungus commonly isolated from soil and associated with a wide range of host plants. We present here three genome sequences of F. avenaceum, one isolated from barley in Finland and two from spring and winter wheat in Canada. The sizes of the three genomes range from 41.6–43.1 MB, with 13217–13445 predicted protein-coding genes. Whole-genome analysis showed that the three genomes are highly syntenic, and share>95% gene orthologs. Comparative analysis to other sequenced Fusaria shows that F. avenaceum has a very large potential for producing secondary metabolites, with between 75 and 80 key enzymes belonging to the polyketide, non-ribosomal peptide, terpene, alkaloid and indole-diterpene synthase classes. In addition to known metabolites from F. avenaceum, fuscofusarin and JM-47 were detected for the first time in this species. Many protein families are expanded in F. avenaceum, such as transcription factors, and proteins involved in redox reactions and signal transduction, suggesting evolutionary adaptation to a diverse and cosmopolitan ecology. We found that 20% of all predicted proteins were considered to be secreted, supporting a life in the extracellular space during interaction with plant hosts. PMID:25409087

  15. The need for culture collections to support plant pathogen diagnostic networks.

    PubMed

    Barba, Marina; Van den Bergh, Inge; Belisario, Alessandra; Beed, Fen

    2010-01-01

    Plant-pathogenic microorganisms, by virtue of their size, similarity in disease symptoms and closely related morphologies, are notoriously difficult to diagnose and detect. Diagnosis gives proof as to the causal agent of disease and is important for developing appropriate control measures. Detection shows the presence of a microorganism and is of importance for safeguarding national and international trade. Live reference collections are required to characterize the taxonomy and function of microorganisms as a prerequisite to development of tools for diagnosis and detection. Two case studies will be presented in this paper to demonstrate the importance of microorganism collections for facilitating knowledge sharing and the development of identification methods. Fusarium wilt of banana caused by Fusarium oxysporum f. sp. cubense and sharka disease of stone fruits caused by plum pox virus (PPV) are considered. Both diseases consist of different races/strains with different host specificities, but Fusarium wilt poses a threat to food security, while PPV poses a threat to trade due to its classification as a quarantine pest, since there is no anti-virus treatment available to control sharka disease in orchards. It is only through comprehensive collections of correctly identified and well-maintained strains representing the genetic diversity of a target organism that robust, specific, reliable and efficient diagnostic and detection tools can be developed. PMID:20457251

  16. FocVel1 influences asexual production, filamentous growth, biofilm formation, and virulence in Fusarium oxysporum f. sp. cucumerinum.

    PubMed

    Li, Peiqian; Pu, Xiaoming; Feng, Baozhen; Yang, Qiyun; Shen, Huifang; Zhang, Jingxin; Lin, Birun

    2015-01-01

    Velvet genes play critical roles in the regulation of diverse cellular processes. In current study, we identified the gene FocVel1, a homolog of Fusarium graminearum VelA, in the plant pathogenic fungus F. oxysporum f. sp. cucumerinum. This pathogen causes the destructive disease called cucumber Fusarium wilt (CFW), which severely affects the production and marketing of this vegetable worldwide. Transcript analyses revealed high expression of FocVel1 during conidiophore development. Disruption of the FocVel1 gene led to several phenotypic defects, including reduction in aerial hyphal formation and conidial production. The deletion mutant ?FocVel1 showed increased resistance to both osmotic stress and cell wall-damaging agents, but increased sensitivity to iprodione and prochloraz fungicides, which may be related to changes in cell wall components. In the process of biofilm formation in vitro, the mutant strain ?FocVel1 displayed not only a reduction in spore aggregation but also a delay in conidial germination on the polystyrene surface, which may result in defects in biofilm formation. Moreover, pathogenicity assays showed that the mutant ?FocVel1 exhibited impaired virulence in cucumber seedlings. And the genetic complementation of the mutant with the wild-type FocVel1 gene restored all the defects of the ?FocVel1. Taken together, the results of this study indicated that FocVel1 played a critical role in the regulation of various cellular processes and pathogenicity in F. oxysporum f. sp. cucumerinum. PMID:25999976

  17. FocVel1 influences asexual production, filamentous growth, biofilm formation, and virulence in Fusarium oxysporum f. sp. cucumerinum

    PubMed Central

    Li, Peiqian; Pu, Xiaoming; Feng, Baozhen; Yang, Qiyun; Shen, Huifang; Zhang, Jingxin; Lin, Birun

    2015-01-01

    Velvet genes play critical roles in the regulation of diverse cellular processes. In current study, we identified the gene FocVel1, a homolog of Fusarium graminearum VelA, in the plant pathogenic fungus F. oxysporum f. sp. cucumerinum. This pathogen causes the destructive disease called cucumber Fusarium wilt (CFW), which severely affects the production and marketing of this vegetable worldwide. Transcript analyses revealed high expression of FocVel1 during conidiophore development. Disruption of the FocVel1 gene led to several phenotypic defects, including reduction in aerial hyphal formation and conidial production. The deletion mutant ?FocVel1 showed increased resistance to both osmotic stress and cell wall-damaging agents, but increased sensitivity to iprodione and prochloraz fungicides, which may be related to changes in cell wall components. In the process of biofilm formation in vitro, the mutant strain ?FocVel1 displayed not only a reduction in spore aggregation but also a delay in conidial germination on the polystyrene surface, which may result in defects in biofilm formation. Moreover, pathogenicity assays showed that the mutant ?FocVel1 exhibited impaired virulence in cucumber seedlings. And the genetic complementation of the mutant with the wild-type FocVel1 gene restored all the defects of the ?FocVel1. Taken together, the results of this study indicated that FocVel1 played a critical role in the regulation of various cellular processes and pathogenicity in F. oxysporum f. sp. cucumerinum. PMID:25999976

  18. alpha-Tomatine, the major saponin in tomato, induces programmed cell death mediated by reactive oxygen species in the fungal pathogen Fusarium oxysporum.

    PubMed

    Ito, Shin-Ichi; Ihara, Takashi; Tamura, Hideyuki; Tanaka, Shuhei; Ikeda, Tsuyoshi; Kajihara, Hiroshi; Dissanayake, Chandrika; Abdel-Motaal, Fatma F; El-Sayed, Magdi A

    2007-07-10

    The tomato saponin alpha-tomatine has been proposed to kill sensitive cells by binding to cell membranes followed by leakage of cell components. However, details of the modes of action of the compound on fungal cells are poorly understood. In the present study, mechanisms involved in alpha-tomatine-induced cell death of fungi were examined using a filamentous pathogenic fungus Fusarium oxysporum. alpha-Tomatine-induced cell death of F. oxysporum (TICDF) occurred only under aerobic conditions and was blocked by the mitochondrial F(0)F(1)-ATPase inhibitor oligomycin, the caspase inhibitor D-VAD-fmk, and protein synthesis inhibitor cycloheximide. Fungal cells exposed to alpha-tomatine showed TUNEL-positive nuclei, depolarization of transmembrane potential of mitochondria, and reactive oxygen species (ROS) accumulation. These results suggest that TICDF occurs through a programmed cell death process in which mitochondria play a pivotal role. Pharmacological studies using inhibitors suggest that alpha-tomatine activates phosphotyrosine kinase and monomeric G-protein signaling pathways leading to Ca(2+) elevation and ROS burst in F. oxysporum cells. PMID:17585910

  19. The ATF/CREB transcription factor Atf1 is essential for full virulence, deoxynivalenol production, and stress tolerance in the cereal pathogen Fusarium graminearum.

    PubMed

    Van Nguyen, Thuat; Kröger, Cathrin; Bönnighausen, Jakob; Schäfer, Wilhelm; Bormann, Jörg

    2013-12-01

    Fusarium graminearum is a necrotrophic plant pathogen of cereals that produces mycotoxins such as deoxynivalenol (DON) and zearalenone (ZEA) in grains. The stress-activated mitogen-activated protein kinase FgOS-2 is a central regulator in F. graminearum and controls, among others, virulence and DON and ZEA production. Here, we characterized the ATF/CREB-activating transcription factor FgAtf1, a regulator that functions downstream of FgOS-2. We created deletion and overexpression mutants of Fgatf1, the latter being also in an FgOS-2 deletion mutant. FgAtf1 localizes to the nucleus and appears to interact with FgOS-2 under osmotic stress conditions. Deletion mutants in Fgatf1 (?Fgatf1) are more sensitive to osmotic stress and less sensitive to oxidative stress compared with the wild type. Furthermore, sexual reproduction is delayed. ?Fgatf1 strains produced higher amounts of DON under in vitro induction conditions than that of the wild type. However, during wheat infection, DON production by ?Fgatf1 is strongly reduced. The ?Fgatf1 strains displayed strongly reduced virulence to wheat and maize. Interestingly, constitutive expression of Fgatf1 in the wild type led to hypervirulence on wheat, maize, and Brachypodium distachyon. Moreover, constitutive expression of Fgatf1 in the ?FgOS-2 mutant background almost complements ?FgOS-2-phenotypes. These data suggest that FgAtf1 may be the most important transcription factor regulated by FgOS-2. PMID:23945004

  20. Natural and natural-like phenolic inhibitors of type B trichothecene in vitro production by the wheat (Triticum sp.) pathogen Fusarium culmorum.

    PubMed

    Pani, Giovanna; Scherm, Barbara; Azara, Emanuela; Balmas, Virgilio; Jahanshiri, Zahra; Carta, Paola; Fabbri, Davide; Dettori, Maria Antonietta; Fadda, Angela; Dessì, Alessandro; Dallocchio, Roberto; Migheli, Quirico; Delogu, Giovanna

    2014-06-01

    Fusarium culmorum, a fungal pathogen of small grain cereals, produces 4-deoxynivalenol and its acetylated derivatives that may cause toxicoses on humans or animals consuming contaminated food or feed. Natural and natural-like compounds belonging to phenol and hydroxylated biphenyl structural classes were tested in vitro to determine their activity on vegetative growth and trichothecene biosynthesis by F. culmorum. Most of the compounds tested at 1.5 or 1.0 mM reduced 3-acetyl-4-deoxynivalenol production by over 70% compared to the control, without affecting fungal growth significantly. Furthermore, several compounds retained their ability to inhibit toxin in vitro production at the lowest concentrations of 0.5 and 0.25 mM. Magnolol 27 showed fungicidal activity even at 0.1 mM. No linear correlation was observed between antioxidant properties of the compounds and their ability to inhibit fungal growth and mycotoxigenic capacity. A guaiacyl unit in the structure may play a key role in trichothecene inhibition. PMID:24820850

  1. The transmembrane protein FgSho1 regulates fungal development and pathogenicity via the MAPK module Ste50-Ste11-Ste7 in Fusarium graminearum.

    PubMed

    Gu, Qin; Chen, Yun; Liu, Ye; Zhang, Chengqi; Ma, Zhonghua

    2015-04-01

    The mitogen-activated protein kinase (MAPK) signaling pathways have been characterized in Fusarium graminearum. Currently, the upstream sensors of these pathways are unknown. Biological functions of a transmembrane protein FgSho1 were investigated using a target gene deletion strategy. The relationship between FgSho1 and the MAPK cassette FgSte50-Ste11-Ste7 was analyzed in depth. The transmembrane protein FgSho1 is required for conidiation, full virulence, and deoxynivalenol (DON) biosynthesis in F. graminearum. Furthermore, FgSho1 and FgSln1 have an additive effect on virulence of F. graminearum. The yeast two-hybrid, coimmunoprecipitation, colocalization and affinity capture-mass spectrometry analyses strongly indicated that FgSho1 physically interacts with the MAPK module FgSte50-Ste11-Ste7. Similar to the FgSho1 mutant, the mutants of FgSte50, FgSte11, and FgSte7 were defective in conidiation, pathogenicity, and DON biosynthesis. In addition, FgSho1 plays a minor role in the response to osmotic stress but it is involved in the cell wall integrity pathway, which is independent of the module FgSte50-Ste11-Ste7 in F. graminearum. Collectively, results of this study strongly indicate that FgSho1 regulates fungal development and pathogenicity via the MAPK module FgSte50-Ste11-Ste7 in F. graminearum, which is different from what is known in the budding yeast Saccharomyces cerevisiae. PMID:25388878

  2. TRANSFORMATION TO PRODUCE BARLEY RESISTANT TO FUSARIUM GRAMINEARUM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fungal pathogen Fusarium graminearum destroys barley and wheat crops by causing scab disease (Fusarium head blight, FHB). Spores infect seed spike tissues, leading to production of mycotoxins. There are no known barleys with biochemical resistance to Fusarium, although some have various levels ...

  3. RNA-Seq analysis reveals new gene models and alternative splicing in the fungal pathogen Fusarium graminearum

    PubMed Central

    2013-01-01

    Background The genome of Fusarium graminearum has been sequenced and annotated previously, but correct gene annotation remains a challenge. In addition, posttranscriptional regulations, such as alternative splicing and RNA editing, are poorly understood in F. graminearum. Here we took advantage of RNA-Seq to improve gene annotations and to identify alternative splicing and RNA editing in F. graminearum. Results We identified and revised 655 incorrectly predicted gene models, including revisions of intron predictions, intron splice sites and prediction of novel introns. 231 genes were identified with two or more alternative splice variants, mostly due to intron retention. Interestingly, the expression ratios between different transcript isoforms appeared to be developmentally regulated. Surprisingly, no RNA editing was identified in F. graminearum. Moreover, 2459 novel transcriptionally active regions (nTARs) were identified and our analysis indicates that many of these could be missed genes. Finally, we identified the 5? UTR and/or 3? UTR sequences of 7666 genes. A number of representative novel gene models and alternatively spliced genes were validated by reverse transcription polymerase chain reaction and sequencing of the generated amplicons. Conclusions We have developed novel and efficient strategies to identify alternatively spliced genes and incorrect gene models based on RNA-Seq data. Our study identified hundreds of alternatively spliced genes in F. graminearum and for the first time indicated that alternative splicing is developmentally regulated in filamentous fungi. In addition, hundreds of incorrect predicted gene models were identified and revised and thousands of nTARs were discovered in our study, which will be helpful for the future genomic and transcriptomic studies in F. graminearum. PMID:23324402

  4. Cytotoxicity and Phytotoxicity of Trichothecene Mycotoxins Produced by Fusarium spp.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Trichothecenes, a major class of mycotoxins produced by Fusarium, Myrothecium, and Stachybotrys species, are toxic to plants, causing blights, wilts and other economically-important plant diseases, and to mammals, for example feed-refusal caused by deoxynivalenol (vomitoxin). Macrocyclic trichothec...

  5. Farkli Fluoresant Pseudomonas (FP) ?zolatlari ve Arbusküler Mikorhizal Fungus (AMF) Glomus intraradices'in Domates'teki Bazi Morfolojik Parametrelere ve Fusarium Solgunlu?una (Fusarium oxysporum f.sp. lycopersici (Sacc) Syd. Et Hans.) Etkisi

    Microsoft Academic Search

    Ahmet AKKÖPRÜ; Hatice ÖZAKTAN

    (2) Abstract: The effects of thirteen nonpathogenic Fluorescent Pseudomonad (FP) isolates and Arbuscular Mycorrhizal Fungus (AMF), Glomus intraradices Schenck &Smith, were examined on some of the morphological parameters (plant length, fresh and dry weight) of tomato and Fusarium wilt (Fusarium oxysporum f.sp. lycopersici (Sacc) Syd. Et Hans.) (FOL) in tomato in pots tests in this research. While G. intraradices (G.i.)

  6. Susceptibility of chrysanthemum and Paris daisy varieties to several isolates of Fusarium oxysporum f. sp. chrysanthemi.

    PubMed

    Garibaldi, A; Bertetti, D; Gullino, M L

    2009-01-01

    Fusarium oxysporum f.sp. chrysonthemi is a pathogen recently reported in Italy on four economically important ornamental crops belonging to the Compositae family: chrysanthemum (Chrysanthemum morifolium), Paris daisy (Argyranthemum frutescens), African daisy (Osteospermum sp.) and gerbera (Gerbera jamesonii). The risk of transmission of the pathogen among these species is high because the hosts are frequently cultivated in the same nursery. The susceptibility of 24 Paris daisy and 12 chrysanthemum cultivars to 10 isolates of F. oxysporum f. sp. chrysanthemi and 3 isolates of F. oxysporum of different origin and to one isolate of F. tracheiphilum from gerbera was tested. Among the tested chrysanthemum cultivars, "Menthise bianco", "Cottonball", "Super Yellow" and "Meribel" were resistant to all the tested strains, while Pingpong gel was resistant to 10 out of 12 isolates. Among the 24 tested cultivars of Paris daisy, only "Sole mio", "Butterfly" and "Maria" were resistant to all isolates of F. oxysporum f.sp. chrysanthemi and to F. tracheiphilum. The results obtained in this work suggest the need of devoting more attention to resistance to Fusarium wilt while developing new varieties of both chrysanthemum and Paris daisy, since only few varieties are resistant to all strains tested. PMID:20222547

  7. Native cell-death genes as candidates for developing wilt resistance in transgenic banana plants

    PubMed Central

    Ghag, Siddhesh B.; Shekhawat, Upendra K. Singh; Ganapathi, Thumballi R.

    2014-01-01

    In order to feed an ever-increasing world population, there is an urgent need to improve the production of staple food and fruit crops. The productivity of important food and fruit crops is constrained by numerous biotic and abiotic factors. The cultivation of banana, which is an important fruit crop, is severely threatened by Fusarium wilt disease caused by infestation by an ascomycetes fungus Fusarium oxysporum f. sp. cubense (Foc). Since there are no established edible cultivars of banana resistant to all the pathogenic races of Foc, genetic engineering is the only option for the generation of resistant cultivars. Since Foc is a hemibiotrophic fungus, investigations into the roles played by different cell-death-related genes in the progression of Foc infection on host banana plants are important. Towards this goal, three such genes namely MusaDAD1, MusaBAG1 and MusaBI1 were identified in banana. The study of their expression pattern in banana cells in response to Foc inoculation (using Foc cultures or fungal toxins like fusaric acid and beauvericin) indicated that they were indeed differentially regulated by fungal inoculation. Among the three genes studied, MusaBAG1 showed the highest up-regulation upon Foc inoculation. Further, in order to characterize these genes in the context of Foc infection in banana, we generated transgenic banana plants constitutively overexpressing the three genes that were later subjected to Foc bioassays in a contained greenhouse. Among the three groups of transgenics tested, transformed banana plants overexpressing MusaBAG1 demonstrated the best resistance towards Foc infection. Further, these plants also showed the highest relative overexpression of the transgene (MusaBAG1) among the three groups of transformed plants generated. Our study showed for the first time that native genes like MusaBAG1 can be used to develop transgenic banana plants with efficient resistance towards pathogens like Foc. PMID:24996429

  8. EVOLUTION OF THE FUSARIUM GRAMINEARUM SPECIES COMPLEX

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight or scab of cereals is one of the most devastating plant diseases worldwide. These pathogens cause significant reduction in seed quality and yields and often contaminate seeds with trichothecene and estrogenic mycotoxins. Genealogical concordance phylogenetic species recognitio...

  9. Surface Survival and Internalization of Salmonella through Natural Cracks on Developing Cantaloupe Fruits, Alone or in the Presence of the Melon Wilt Pathogen Erwinia tracheiphila

    PubMed Central

    Gautam, Dhiraj; Dobhal, Shefali; Payton, Mark E.; Fletcher, Jacqueline; Ma, Li Maria

    2014-01-01

    Outbreaks of foodborne illness attributed to the consumption of Salmonella-tainted cantaloupe have occurred repeatedly, but understanding of the ecology of Salmonella on cantaloupe fruit surfaces is limited. We investigated the interactions between Salmonella enterica Poona, the plant pathogenic bacterium Erwinia tracheiphila, and cantaloupe fruit. Fruit surfaces were inoculated at the natural cracking stage by spreading S. enterica and E. tracheiphila, 20 µl at 107 cfu/ml, independently or together, over a 2×2 cm rind area containing a crack. Microbial and microscopic analyses were performed at 0, 9 and 24 days post inoculation (DPI). Even at 24 DPI (fruit maturity) S. enterica was detected on 14% and 40% of the fruit inoculated with S. enterica alone and the two-pathogen mixture, respectively. However, the population of S. enterica declined gradually after initial inoculation. E. tracheiphila, inoculated alone or together with Salmonella, caused watersoaked lesions on cantaloupe fruit; but we could not conclude in this study that S. enterica survival on the fruit surface was enhanced by the presence of those lesions. Of fruit inoculated with E. tracheiphila alone and sampled at 24 DPI, 61% had watersoaked lesions on the surface. In nearly half of those symptomatic fruits the watersoaking extended into the sub-rind mesocarp, and E. tracheiphila was recovered from that tissue in 50% of the symptomatic fruit. In this work, E. tracheiphila internalized through natural cracks on developing fruits. S. enterica was never detected in the fruit interior (ca. 2–3 mm below rind surface) under the limited conditions of our experiments, but the possibility that it, or other human pathogens that contaminate fresh produce, might also do so should be investigated under a wider range of conditions and produce types. PMID:25147942

  10. Effects of water regime, crop residues, and application rates on control of Fusarium oxysporum f. sp. cubense.

    PubMed

    Wen, Teng; Huang, Xinqi; Zhang, Jinbo; Zhu, Tongbin; Meng, Lei; Cai, Zucong

    2015-05-01

    Biological soil disinfestation is an effective method to control soil-borne disease by flooding and incorporating with organic amendments, but field conditions and resources sometimes limited its practical application. A laboratory experiment was conducted to develop practice guidelines on controlling Fusarium wilt, a widespread banana disease caused by Fusarium oxysporum f. sp. cubense (FOC). FOC infested soil incorporated with rice or maize straw at rates of 1.5tons/ha and 3.0tons/ha was incubated under flooded or water-saturated (100% water holding capacity) conditions at 30°C for 30days. Results showed that FOC populations in the soils incorporated with either rice or maize straw rapidly reduced more than 90% in the first 15days and then fluctuated till the end of incubation, while flooding alone without organic amendment reduced FOC populations slightly. The rapid and dramatic decrease of redox potential (down to -350mV) in straw-amended treatments implied that both anaerobic condition and strongly reductive soil condition would contribute to pathogen inactivation. Water-saturation combined with straw amendments had the comparable effects on reduction of FOC, indicating that flooding was not indispensable for inactivating FOC. There was no significant difference in the reduction of FOC observed in the straw amendments at between 1.5 and 3tons/ha. Therefore, incorporating soil with straw (rice or maize straw) at a rate of 3.0tons/ha under 100% water holding capacity or 1.5tons/ha under flooding, would effectively alleviate banana Fusarium wilt caused by FOC after 15-day treating under 30°C. PMID:25968255

  11. Root Exudates from Grafted-Root Watermelon Showed a Certain Contribution in Inhibiting Fusarium oxysporum f. sp. niveum

    PubMed Central

    Wang, Dongsheng; Mao, Jiugeng; Huang, Qiwei; Guo, Shiwei; Shen, Qirong

    2013-01-01

    Grafting watermelon onto bottle gourd rootstock is commonly used method to generate resistance to Fusarium oxysporum f. sp. niveum (FON), but knowledge of the effect of the root exudates of grafted watermelon on this soil-borne pathogen in rhizosphere remains limited. To investigate the root exudate profiles of the own-root bottle gourd, grafted-root watermelon and own-root watermelon, recirculating hydroponic culture system was developed to continuously trap these root exudates. Both conidial germination and growth of FON were significantly decreased in the presence of root exudates from the grafted-root watermelon compared with the own-root watermelon. HPLC analysis revealed that the composition of the root exudates released by the grafted-root watermelon differed not only from the own-root watermelon but also from the bottle gourd rootstock plants. We identified salicylic acid in all 3 root exudates, chlorogenic acid and caffeic acid in root exudates from own-root bottle gourd and grafted-root watermelon but not own-root watermelon, and abundant cinnamic acid only in own-root watermelon root exudates. The chlorogenic and caffeic acid were candidates for potentiating the enhanced resistance of the grafted watermelon to FON, therefore we tested the effects of the two compounds on the conidial germination and growth of FON. Both phenolic acids inhibited FON conidial germination and growth in a dose-dependent manner, and FON was much more susceptible to chlorogenic acid than to caffeic acid. In conclusion, the key factor in attaining the resistance to Fusarium wilt is grafting on the non-host root stock, however, the root exudates profile also showed some contribution in inhibiting FON. These results will help to better clarify the disease resistance mechanisms of grafted-root watermelon based on plant-microbe communication and will guide the improvement of strategies against Fusarium-mediated wilt of watermelon plants. PMID:23700421

  12. Immunocytochemical localization of fusarium toxins in infected wheat spikes by Fusarium culmorum

    Microsoft Academic Search

    Z KANG; H BUCHENAUER

    1999-01-01

    Two antisera raised against deoxynivalenol (DON) and 3-acetyldeoxynivalenol (3-ADON) were used to investigate the subcellular localization of the fusarium toxins, DON, 3-ADON and 15-ADON, in Fusarium culmorum infected wheat spikes and kernels by means of the immunogold labelling technique. The hyphae of the pathogen produced the toxins when they grew on the surface of the lemma and the ovary as

  13. GENOMIC ANALYSIS OF FUSARIUM VERTICILLIOIDES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides (teleomorph Gibberella moniliformis) can be either an endophyte of maize, causing no visible disease, or a pathogen causing disease of ears, stalks, roots and seedlings. At any stage, this fungus can synthesize fumonisins, a family of mycotoxins structurally similar to the ...

  14. Genomic analysis of Fusarium verticillioides

    Microsoft Academic Search

    D. W. Brown; R. A. E. Butchko; R. H. Proctor

    2008-01-01

    Fusarium verticillioides (teleomorph Gibberella moniliformis) can be either an endophyte of maize, causing no visible disease, or a pathogen-causing disease of ears, stalks, roots and seedlings. At any stage, this fungus can synthesize fumonisins, a family of mycotoxins structurally similar to the sphingolipid sphinganine. Ingestion of fumonisin-contaminated maize has been associated with a number of animal diseases, including cancer in

  15. Root defense analysis against Fusarium oxysporum reveals new regulators to confer resistance

    PubMed Central

    Chen, Yi Chung; Wong, Chin Lin; Muzzi, Frederico; Vlaardingerbroek, Ido; Kidd, Brendan N.; Schenk, Peer M.

    2014-01-01

    Fusarium oxysporum is a root-infecting fungal pathogen that causes wilt disease on a broad range of plant species, including Arabidopsis thaliana. Investigation of the defense response against this pathogen had primarily been conducted using leaf tissue and little was known about the root defense response. In this study, we profiled the expression of root genes after infection with F. oxysporum by microarray analysis. In contrast to the leaf response, root tissue did not show a strong induction of defense-associated gene expression and instead showed a greater proportion of repressed genes. Screening insertion mutants from differentially expressed genes in the microarray uncovered a role for the transcription factor ETHYLENE RESPONSE FACTOR72 (ERF72) in susceptibility to F. oxysporum. Due to the role of ERF72 in suppressing programmed cell death and detoxifying reactive oxygen species (ROS), we examined the pub22/pub23/pub24 U-box type E3 ubiquitin ligase triple mutant which is known to possess enhanced ROS production in response to pathogen challenge. We found that the pub22/23/24 mutant is more resistant to F. oxysporum infection, suggesting that a heightened innate immune response provides protection against F. oxysporum. We conclude that root-mediated defenses against soil-borne pathogens can be provided at multiple levels. PMID:24998294

  16. [Identification of phenylacetic acid produced by Fusarium oxysporum f. sp. albedinis, the causal agent of bayoud, using GC-MS].

    PubMed

    Ait Kettout, T; Rahmania, F

    2010-01-01

    These studies are concerned with the isolation and identification of secondary metabolites produced by Fusarium oxysporum f. sp. albedinis (F. o. a.), the causal agent of bayoud, the wilt disease of the date palm (Phoenix dactylifera L.). Fungal secondary metabolites are chemical compounds identified in a limited number of species. They consist of toxins, antibiotics and antifungal agents. Among the metabolites we could isolate from the pathogen grown in a liquid medium, and then identify by gas chromatography coupled with mass spectrometry (GC-MS), phenylacetic acid has been distinguished. This compound is widely described in the literature as having antimicrobial, antifungal, phytotoxic properties and also endowed with hormonal activity similar to that of indole acetic acid (IAA). To date, this metabolite has never been reported in F. o. a. PMID:21146137

  17. Verticillium Wilt Resistance Evaluation of Wisconsin Breeding Clones

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Verticillium wilt is one of the most widespread and persistent problems encountered by potato producers. In Wisconsin, it is caused in large part by the fungal pathogen Verticillium dahliae. Soil fumigation is currently the only consistently effective control measure. However, host plant resistan...

  18. The Fusarium oxysporum effector Six6 contributes to virulence and suppresses I-2-mediated cell death.

    PubMed

    Gawehns, F; Houterman, P M; Ichou, F Ait; Michielse, C B; Hijdra, M; Cornelissen, B J C; Rep, M; Takken, F L W

    2014-04-01

    Plant pathogens secrete effectors to manipulate their host and facilitate colonization. Fusarium oxysporum f. sp. lycopersici is the causal agent of Fusarium wilt disease in tomato. Upon infection, F. oxysporum f. sp. lycopersici secretes numerous small proteins into the xylem sap (Six proteins). Most Six proteins are unique to F. oxysporum, but Six6 is an exception; a homolog is also present in two Colletotrichum spp. SIX6 expression was found to require living host cells and a knockout of SIX6 in F. oxysporum f. sp. lycopersici compromised virulence, classifying it as a genuine effector. Heterologous expression of SIX6 did not affect growth of Agrobacterium tumefaciens in Nicotiana benthamiana leaves or susceptibility of Arabidopsis thaliana toward Verticillium dahliae, Pseudomonas syringae, or F. oxysporum, suggesting a specific function for F. oxysporum f. sp. lycopersici Six6 in the F. oxysporum f. sp. lycopersici- tomato pathosystem. Remarkably, Six6 was found to specifically suppress I-2-mediated cell death (I2CD) upon transient expression in N. benthamiana, whereas it did not compromise the activity of other cell-death-inducing genes. Still, this I2CD suppressing activity of Six6 does not allow the fungus to overcome I-2 resistance in tomato, suggesting that I-2-mediated resistance is independent from cell death. PMID:24313955

  19. The development and application of a plant bioassay to elucidate toxic principles directed at watermelon by Fusarium Oxysporum f. sp. niveum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Formae speciales of Fusarium oxysporum cause wilt and death of numerous agronomic crops worldwide. The objective of this research was to develop a bioassay for Fusarium toxins directed toward watermelon. Watermelon seedlings were grown to the two leaf stage; the roots were washed and trimmed. Two...

  20. Detection of Fusarium oxysporum f.sp. basilici in substrates and roots by PCR.

    PubMed

    Pugliese, M; Ferrocino, I; Gullino, M L; Garibaldi, A

    2013-01-01

    Fusarium oxysporum is a soil-borne fungus that causes vascular wilts in a wide variety of plant species. Basil is recognized as an ecological niche for Fusarium oxysporum f.sp. basilici (FOB) and this fungus is now present in most countries where basil is cultivated. The rapid identification of the species affecting basil plants is necessary to define a successful method for crop protection. The aim of this study was to develop a PCR method for the rapid detection of Fusarium oxysporum f. sp. basilici in substrates. The specificity of the primers used was tested using the DNA extracted directly from substrate samples. Fusarium oxysporum f.sp. basilici was artificially inoculated with decreasing amounts in a commercial substrate (sphagnum peat moss) and in a mixture with 40% of municipal compost, after steam disinfestation. Basil seeds (cv. Fine verde) were sown in pots that were laid on a bench in the greenhouse. At time 0 and after 7, 14 and 21 days from the inoculation, substrate and root samples were collected and prepared for microbial analysis and for the DNA extraction. DNA extraction was carried out using NucleoSpin Soil Kit (Macherey-Nagel, Germany). PCR amplification for the specific detection was carried out using primer sets Bik 1 (5'-ATT CAA GAG CTA AAG GTC C-3') and Bik 4 (5'-TTT GAC CAA GAT AGA TGC C-3') for the first PCR, while primers Bik 1 + Bik 2 (5'-AAA GGT AGT ATA TCG GAG G-3') for the nested PCR to increase detection sensitivity. Disease incidence was also assessed 21 days after seeding. The results showed the presence of amplified fragments of the expected size when the concentration of F. oxysporum f.sp. basilici was at least 3.5 Log CFU g(-1) by using DNA extract directly from substrate, before roots were infected by the pathogen. The detection of Fusarium oxysporum f. sp. basilici by PCR method developed in this study is certainly simple and fast and can be useful for its reliable detection in substrate samples, but not to guarantee that the substrate is totally free of pathogens. PMID:25151841

  1. Deciphering the cryptic genome: Genome-wide analyses of the rice pathogen Fusarium fujikuroi reveal complex regulation of secondary metabolism and novel metabolites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fungus Fusarium fujikuroi is agriculturally important because it produces the phytohormones gibberellic acids (GAs) and causes bakanae (“foolish seedling”) disease of rice. The fungus also produces multiple other secondary metabolites, including pigments and mycotoxins. Here, we present a high-q...

  2. The photolyase gene from the plant pathogen Fusarium oxysporum f. sp. lycopersici is induced by visible light and ?-tomatine from tomato plant

    Microsoft Academic Search

    Encarna Alejandre-Durán; Teresa Roldán-Arjona; Rafael R Ariza; Manuel Ruiz-Rubio

    2003-01-01

    Survival of irradiated spores from Fusarium oxysporum with ultraviolet radiation (UV) was increased following exposition to visible light, indicating that this phytopathogenic fungus has a mechanism of photoreactivation able to counteract the lethal effects of UV. A genomic sequence containing the complete photolyase gene (phr1) from F. oxysporum was isolated by heterologous hybridisation with the Neurospora crassa photolyase gene. The

  3. Fusarium euwallaceae sp. nov.--a symbiotic fungus of Euwallacea sp., an invasive ambrosia beetle in Israel and California.

    PubMed

    Freeman, S; Sharon, M; Maymon, M; Mendel, Z; Protasov, A; Aoki, T; Eskalen, A; O'Donnell, K

    2013-01-01

    The invasive Asian ambrosia beetle Euwallacea sp. (Coleoptera, Scolytinae, Xyleborini) and a novel Fusarium sp. that it farms in its galleries as a source of nutrition causes serious damage to more than 20 species of live trees and pose a serious threat to avocado production (Persea americana) in Israel and California. Adult female beetles are equipped with mandibular mycangia in which its fungal symbiont is transported within and from the natal galleries. Damage caused to the xylem is associated with disease symptoms that include sugar or gum exudates, dieback, wilt and ultimately host tree mortality. In 2012 the beetle was recorded on more than 200 and 20 different urban landscape species in southern California and Israel respectively. Euwallacea sp. and its symbiont are closely related to the tea shot-hole borer (E. fornicatus) and its obligate symbiont, F. ambrosium occurring in Sri Lanka and India. To distinguish these beetles, hereafter the unnamed xyleborine in Israel and California will be referred to as Euwallacea sp. IS/CA. Both fusaria exhibit distinctive ecologies and produce clavate macroconidia, which we think might represent an adaption to the species-specific beetle partner. Both fusaria comprise a genealogically exclusive lineage within Clade 3 of the Fusarium solani species complex (FSSC) that can be differentiated with arbitrarily primed PCR. Currently these fusaria can be distinguished only phenotypically by the abundant production of blue to brownish macroconidia in the symbiont of Euwallacea sp. IS/CA and their rarity or absence in F. ambrosium. We speculate that obligate symbiosis of Euwallacea and Fusarium, might have driven ecological speciation in these mutualists. Thus, the purpose of this paper is to describe and illustrate the novel, economically destructive avocado pathogen as Fusarium euwallaceae sp. nov. S. Freeman et al. PMID:23928415

  4. Challenges in Controlling Verticillium Wilt by the Use of Nonchemical Methods

    Microsoft Academic Search

    George Lazarovits; Krishnamurthy Subbarao

    \\u000a Verticillium wilt is one of the most serious soilborne diseases worldwide. Three non-fumigant control methods that appear\\u000a to have great potential for reducing losses due to wilt and other soilborne pathogens are detailed here. High nitrogen organic\\u000a amendments and products containing volatile fatty acids (VFAs) can significantly reduce disease severity and inoculum density\\u000a but only under specific soil conditions. Identification

  5. BEET ROOT-ROT INDUCING ISOLATES OF FUSARIUM OXYSPORUM FROM COLORADO AND MONTANA.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium root rot, a rot of the root top of sugar beet, caused by Fusarium oxysporum has been confirmed only in Texas, USDA, to date. Isolates of Fusarium were obtained from beets with tip rot symptoms from Montana and Colorado. Isolates were identified and tested for pathogenicity on sugar beet. ...

  6. Specific Detection of Fusarium Species in Blood and Tissues by a PCR Technique

    Microsoft Academic Search

    FRANCOIS-XAVIER HUE; MICHEL HUERRE; MARIE ANGE ROUFFAULT; CLAUDE DE BIEVRE

    1999-01-01

    Fusarium species are opportunistic nosocomial pathogens that often cause fatal invasive mycoses. We designed a primer pair that amplifies by PCR a fragment of a gene coding for the rRNA of Fusarium species. The DNAs of the main Fusarium species and Neocosmospora vasinfecta but not the DNAs from 11 medically important fungi were amplified by these primers. The lower limit

  7. Distinct colonization patterns and cDNA-AFLP transcriptome profiles in compatible and incompatible interactions between melon and different races of Fusarium oxysporum f. sp. melonis

    PubMed Central

    2011-01-01

    Background Fusarium oxysporum f. sp. melonis Snyd. & Hans. (FOM) causes Fusarium wilt, the most important infectious disease of melon (Cucumis melo L.). The four known races of this pathogen can be distinguished only by infection on appropriate cultivars. No molecular tools are available that can discriminate among the races, and the molecular basis of compatibility and disease progression are poorly understood. Resistance to races 1 and 2 is controlled by a single dominant gene, whereas only partial polygenic resistance to race 1,2 has been described. We carried out a large-scale cDNA-AFLP analysis to identify host genes potentially related to resistance and susceptibility as well as fungal genes associated with the infection process. At the same time, a systematic reisolation procedure on infected stems allowed us to monitor fungal colonization in compatible and incompatible host-pathogen combinations. Results Melon plants (cv. Charentais Fom-2), which are susceptible to race 1,2 and resistant to race 1, were artificially infected with a race 1 strain of FOM or one of two race 1,2 w strains. Host colonization of stems was assessed at 1, 2, 4, 8, 14, 16, 18 and 21 days post inoculation (dpi), and the fungus was reisolated from infected plants. Markedly different colonization patterns were observed in compatible and incompatible host-pathogen combinations. Five time points from the symptomless early stage (2 dpi) to obvious wilting symptoms (21 dpi) were considered for cDNA-AFLP analysis. After successful sequencing of 627 transcript-derived fragments (TDFs) differentially expressed in infected plants, homology searching retrieved 305 melon transcripts, 195 FOM transcripts expressed in planta and 127 orphan TDFs. RNA samples from FOM colonies of the three strains grown in vitro were also included in the analysis to facilitate the detection of in planta-specific transcripts and to identify TDFs differentially expressed among races/strains. Conclusion Our data suggest that resistance against FOM in melon involves only limited transcriptional changes, and that wilting symptoms could derive, at least partially, from an active plant response. We discuss the pathogen-derived transcripts expressed in planta during the infection process and potentially related to virulence functions, as well as transcripts that are differentially expressed between the two FOM races grown in vitro. These transcripts provide candidate sequences that can be further tested for their ability to distinguish between races. Sequence data from this article have been deposited in GenBank, Accession Numbers: HO867279-HO867981. PMID:21338485

  8. Isolation and Heterologous Expression of a Polygalacturonase Produced by Fusarium oxysporum f. sp. cubense Race 1 and 4

    PubMed Central

    Dong, Zhangyong; Wang, Zhenzhong

    2015-01-01

    Fusarium wilt (Panama disease) caused by Fusarium oxysporum f. sp. cubense (FOC) represents a significant threat to banana (Musa spp.) production. Musa AAB is susceptible to Race 1 (FOC1) and Race 4 (FOC4), while Cavendish Musa AAA is found to be resistant to FOC1 but still susceptible to Race 4. A polygalacturonase (PGC3) was purified from the supernatant of Fusarium oxysporum f. sp. cubense race 4 (FOC4), which is the pathogen of Fusarium wilt. PGC3 had an apparent molecular weight of 45 kDa according to SDS-PAGE. The enzyme hydrolyzed polygalacturonic acid in an exo-manner, as demonstrated by analysis of degradation products. The Km and Vmax values of PGC3 from FOC4 were determined to be 0.70 mg·mL?1 and 101.01 Units·mg·protein?1·min?1, respectively. Two pgc3 genes encoding PGC3 from FOC4 and FOC1, both genes of 1368 bp in length encode 456 amino-acid residues with a predicted signal peptide sequence of 21 amino acids. There are 16 nucleotide sites difference between FOC4-pgc3 and FOC1-pgc3, only leading to four amino acid residues difference. In order to obtain adequate amounts of protein required for functional studies, two genes were cloned into the expression vector pPICZaA and then expressed in Pichia pastoris strains of SMD1168. The recombinant PGC3, r-FOC1-PGC3 and r-FOC4-PGC3, were expressed and purified as active proteins. The optimal PGC3 activity was observed at 50 °C and pH 4.5. Both recombinant PGC3 retained >40% activity at pH 3–7 and >50% activity in 10–50 °C. Both recombinant PGC3 proteins could induce a response but with different levels of tissue maceration and necrosis in banana plants. In sum, our results indicate that PGC3 is an exo-PG and can be produced with full function in P. pastoris. PMID:25854430

  9. Efficacy of microorganisms selected from compost to control soil-borne pathogens.

    PubMed

    Pugliese, M; Gullino, M L; Garibaldi, A

    2010-01-01

    Suppression of soil-borne plant pathogens with compost has been widely studied. Compost has been found to be suppressive against several soil-borne pathogens in various cropping systems. However, an increase of some diseases due to compost usage has also been observed, since compost is a product that varies considerably in chemical, physical and biotic composition, and, consequently, also in ability to suppress soil borne diseases. New opportunities in disease management can be obtained by the selection of antagonists from suppressive composts. The objective of the present work was to isolate microorganisms from a suppressive compost and to test them for their activity against soil-borne pathogens. A compost from green wastes, organic domestic wastes and urban sludge's that showed a good suppressive activity in previous trials was used as source of microorganisms. Serial diluted suspensions of compost samples were plated on five different media: selective for Fusarium sp., selective for Trichoderma sp., selective for oomycetes, potato dextrose agar (PDA) for isolation of fungi, lysogeny broth (LB) for isolation of bacteria. In total, 101 colonies were isolated from plates and tested under laboratory conditions on tomato seedlings growing on perlite medium in Petri plates infected with Fusarium oxysporum f.sp. radicis-lycopersici and compared to a commercial antagonist (Streptomyces griserovidis, Mycostop, Bioplanet). Among them, 28 showed a significant disease reduction and were assessed under greenhouse condition on three pathosystems: Fusarium oxysporum f.sp. basilica/basil, Phytophthora nicotianae/tomato and Rhizoctonia solani/bean. Fusarium spp. selected from compost generally showed a good disease control against Fusarium wilts, while only bacteria significantly controlled P. nicotianae on tomato under greenhouse conditions. None of the microorganisms was able to control the three soil-borne pathogens together, in particular Rhizoctonia solani. Results confirmed the good suppressive activity of the compost under study against soil-borne pathogens. The selection of antagonists from compost is a promising strategy for the development of new biological control agents against soil-borne pathogens. PMID:21534476

  10. Other Fusarium - Associated Problems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In addition to Fusarium yellows and Fusarium root rot, caused by Fusarium oxysporum, other species of Fusarium can infect sugar beet and cause foliar yellowing, root rot, or other symptoms. The importance of many of these problems is not well understood. This chapter discusses some of what is know...

  11. Plant Disease Lesson: Fusarium head blight (FHB) or scab

    NSDL National Science Digital Library

    David G. Schmale III (Cornell University; )

    2003-06-12

    This plant disease lesson on Fusarium head blight (FHB) or scab (caused by the fungus Fusarium graminearum (anamorph) Gibberella zeae (teleomorph)) includes information on symptoms and signs, pathogen biology, disease cycle and epidemiology, disease management, and the significance of the disease. Selected references are listed and a glossary is also available for use with this resource.

  12. Diversity of the Fusarium graminearum species complex on French cereals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium graminearum is an important pathogen causing Fusarium head blight (FHB) on wheat and barley and Gibberella ear rot (GER) on maize, and harvested grains often are contaminated with trichothecenes such as deoxynivalenol (DON) and nivalenol (NIV) that are a major health and food safety concern...

  13. Variation in the Trichothecene Mycotoxin Biosynthetic Gene Cluster in Fusarium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Trichothecene mycotoxins are produced by some plant pathogenic species of the fungus Fusarium and can contribute to its virulence on some plants. In Fusarium graminearum and F. sporotrichioides trichothecene biosynthetic enzymes are encoded at three loci: the single-gene TRI101 locus; the two-gene ...

  14. Induced Resistance and Interspecific Competition between Spider Mites and a Vascular Wilt Fungus

    Microsoft Academic Search

    Richard Karban; Rodney Adamchak; William C. Schnathorst

    1987-01-01

    The fungal pathogen Verticillium dahliae was less likely to cause symptoms of verticillium wilt on cotton seedlings that had been previously exposed to spider mites than on unexposed cotton seedlings. Conversely, populations of the spider mite Tetranychus urticae grew less rapidly on seedlings that had been inoculated with V. dahliae than on uninoculated controls. Changes caused by pathogen or herbivore

  15. Fusarium Wilt and Yellows of Sugar Beet and Dry Bean

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Central High Plains (Colorado, Nebraska and Wyoming) is among the largest producer of dry edible beans and sugar beets in the United States. Sugar beet is an important cash crop in northeastern Colorado with approximately 30,000 acres planted and 944,000 tons harvested in 2012. Approximately 250...

  16. Three improved Citrullus lanatus var. citroides lines USVL246-FR2, USVL252-FR2, and USVL335-FR2, with resistance to Fusarium oxysporum f. sp. niveum race 2

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt (FW) is a major disease of watermelon in North America and around the world. Control of this disease is difficult because the soil-borne causal agent Fusarium oxysporum f. sp. niveum (Fon) produces chlamydospores that remain infectious in the soil for many years. Although, various le...

  17. A major QTL associated with Fusarium oxysporum race 1 resistance identified in genetic populations derived from closely related watermelon lines using selective genotyping and genotyping-by-sequencing for SNP discovery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt is a major soil-borne disease of watermelon caused by the fungus Fusarium oxysporum Schlechtend.:Fr. f. sp. niveum (E.F. Sm.) W.C. Snyder & H.N. Hans (Fon). In this study, a genetic population of 186 F3 families (24 plants in each family) exhibited continuous distribution for Fon race ...

  18. Genotypic and Phenotypic Characterization of Fungi in the Fusarium oxysporum Species Complex from Soybean Roots.

    PubMed

    Ellis, Margaret L; Jimenez, David R Cruz; Leandro, Leonor F; Munkvold, Gary P

    2014-12-01

    Isolates in the Fusarium oxysporum species complex (FOSC) from soybean range from nonpathogenic to aggressive pathogens causing seedling damping-off, wilt, and root rot. The objective of this research was to characterize the genotype and phenotype of isolates within the FOSC recovered predominantly from soybean roots and seedlings. Sequence analyses of the translation elongation factor (tef1?) gene and the mitochondrial small subunit (mtSSU), polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis of the intergenic spacer (IGS) region, and identification of the mating type loci were conducted for 170 isolates. Vegetative compatibility (VC) tests were conducted for 114 isolates. Isolate aggressiveness was tested using a rolled towel assay for 159 isolates. Phylogenetic analysis of the tef1? and mtSSU and PCR-RFLP analysis of the IGS region separated the FOSC isolates into five clades, including F. commune. Both mating type loci, MAT1-1 or MAT1-2, were present in isolates from all clades. The VC tests were not informative, because most VC groups consisted of a single isolate. Isolate aggressiveness varied within and among clades; isolates in clade 2 were significantly less aggressive (P < 0.0001) when compared with isolates from the other clades and F. commune. The results from this study demonstrate the high levels of genotypic and phenotypic diversity within the FOSC from soybean but further work is needed to identify characteristics associated with pathogenic capabilities. PMID:24983844

  19. Molecular characterization of an endopolygalacturonase from Fusarium oxysporum expressed during early stages of infection.

    PubMed

    García-Maceira, F I; Di Pietro, A; Huertas-González, M D; Ruiz-Roldán, M C; Roncero, M I

    2001-05-01

    The tomato vascular wilt pathogen Fusarium oxysporum f. sp. lycopersici produces an array of pectinolytic enzymes that may contribute to penetration and colonization of the host plant. Here we report the isolation of pg5, encoding a novel extracellular endopolygalacturonase (endoPG) that is highly conserved among different formae speciales of F. oxysporum. The putative mature pg5 product has a calculated molecular mass of 35 kDa and a pI of 8.3 and is more closely related to endoPGs from other fungal plant pathogens than to PG1, the major endoPG of F. oxysporum. Overexpression of pg5 in a bacterial heterologous system produced a 35-kDa protein with endoPG activity. Accumulation of pg5 transcript is induced by citrus pectin and D-galacturonic acid and repressed by glucose. As shown by reverse transcription-PCR, pg5 is expressed by F. oxysporum in tomato roots during the initial stages of infection. Targeted inactivation of pg5 has no detectable effect on virulence toward tomato plants. PMID:11319099

  20. Fusarium oxysporum Triggers Tissue-Specific Transcriptional Reprogramming in Arabidopsis thaliana

    PubMed Central

    Lyons, Rebecca; Stiller, Jiri; Powell, Jonathan; Rusu, Anca; Manners, John M.; Kazan, Kemal

    2015-01-01

    Some of the most devastating agricultural diseases are caused by root-infecting pathogens, yet the majority of studies on these interactions to date have focused on the host responses of aerial tissues rather than those belowground. Fusarium oxysporum is a root-infecting pathogen that causes wilt disease on several plant species including Arabidopsis thaliana. To investigate and compare transcriptional changes triggered by F. oxysporum in different Arabidopsis tissues, we infected soil-grown plants with F. oxysporum and subjected root and leaf tissue harvested at early and late timepoints to RNA-seq analyses. At least half of the genes induced or repressed by F. oxysporum showed tissue-specific regulation. Regulators of auxin and ABA signalling, mannose binding lectins and peroxidases showed strong differential expression in root tissue. We demonstrate that ARF2 and PRX33, two genes regulated in the roots, promote susceptibility to F. oxysporum. In the leaves, defensins and genes associated with the response to auxin, cold and senescence were strongly regulated while jasmonate biosynthesis and signalling genes were induced throughout the plant. PMID:25849296

  1. Water balance altered in cucumber plants infected with Fusarium oxysporum f. sp. cucumerinum

    PubMed Central

    Wang, Min; Sun, Yuming; Sun, Guomei; Liu, Xiaokang; Zhai, Luchong; Shen, Qirong; Guo, Shiwei

    2015-01-01

    Fusarium wilt is caused by the infection and growth of the fungus Fusarium oxysporum in the xylem of host plants. The physiological responses of cucumbers that are infected with Fusarium oxysporum f. sp. cucumerinum (FOC) was studied in pot and hydroponic experiments in a greenhouse. The results showed that although water absorption and stem hydraulic conductance decreased markedly in infected plants, large amounts of red ink accumulated in the leaves of infected cucumber plants. The transpiration rate (E) and stomatal conductance (gs) of the infected plants were significantly reduced, but the E/gs was higher than healthy plants. We further found that there was a positive correlation between leaf membrane injury and E/gs, indicating that the leaf cell membrane injury increased the non-stomatal water loss from infected plants. The fusaric acid (FA), which was detected in the infected plant, resulted in damage to the leaf cell membranes and an increase in E/gs, suggesting that FA plays an important role in non-stomatal water loss. In conclusion, leaf cell membrane injury in the soil-borne Fusarium wilt of cucumber plants induced uncontrolled water loss from damaged cells. FA plays a critical role in accelerating the development of Fusarium wilt in cucumber plants. PMID:25579504

  2. First Report of Bacterial Wilt Caused by Ralstonia solanacearum Biovar 2 Race 1 on Tomato in Egypt.

    PubMed

    Seleim, Mohamed A A; Abo-Elyousr, Kamal A M; Abd-El-Moneem, Kenawy M; Saead, Farag A

    2014-09-01

    This study aims to isolate and identify the causal pathogen of tomato bacterial wilt in Egypt. In 2008, tomato plants showing typical symptoms of bacterial wilt disease with no foliar yellowing were observed in Minia, Assiut and Sohag governorates, Egypt. When cut stems of symptomatic plants were submerged in water, whitish ooze was evident and longitudinal sections showed a brown discoloration in the vascular tissues. Bacteria were isolated on triphenyl tetrazolium chloride medium and fifteen isolates shown typical morphological and cultural characteristics were confirmed as Ralstonia solanacearum biovar 2 race 1. Pathogenicity tests showed that all isolates proved to be pathogenic to tomato plants, varied from 52 to 97% wilting. This is the first report of R. solanacearum biovar 2 race 1 causing bacterial wilt in tomato crop in Egypt. PMID:25289016

  3. Differentiation of Fusarium oxysporum isolates from Phoenix canadensis (Canary Island Date Palm) by vegetative compatibility grouping and molecular analysis

    Microsoft Academic Search

    L. V. Gunn; B. A. Summerell

    2002-01-01

    Fusarium wilt of Phoenix canariensis (Canary Island Date Palm) is caused by Fusarium oxysporum f. sp. canariensis (Foc). The disease occurs worldwide, including Australia where hundreds of palms have been killed. Isolates of Foc were collected from fronds of diseased palms at sites around Sydney and different parts (non-frond) of individual palms within\\u000a a site. Three techniques were used to

  4. Genetic characteristics of Fusarium verticillioides from corn in the Philippines

    Microsoft Academic Search

    Christian Joseph R. Cumagun; Josephine S. Ramos; Arvin O. Dimaano; Françoise Munaut; François Van Hove

    2009-01-01

    Fusarium verticillioides (teleomorph: Gibberella moniliformis = G. fujikuroi mating population A) is one of the most important fungal pathogens of corn worldwide. The pathogen produces fumonisins, mycotoxins\\u000a that are potentially harmful to humans and animals. Thirty-five Fusarium isolates from Laguna and Isabela, Philippines were identified morphologically and molecularly as F. verticillioides and characterized by PCR for mating type (MAT). Twenty-six isolates were

  5. Wilts of the Watermelon and Related Crops: Fusarium Wilts of Cucurbits.

    E-print Network

    Taubenhaus, J. J. (Jacob Joseph)

    1920-01-01

    these experiments it was con- clusivcly provecl that both squach npd watermelon milts are distinct and that it is possiblr: to grow healthy watermelons in a squash sick land provided the watermelon F'nearium is kept out. Likewise, it is possible to grow healthy...

  6. Molecular Identification and Databases in Fusarium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    DNA sequence-based methods for identifying pathogenic and mycotoxigenic Fusarium isolates have become the gold standard worldwide. Moreover, fusarial DNA sequence data are increasing rapidly in several web-accessible databases for comparative purposes. Unfortunately, the use of Basic Alignment Sea...

  7. Mycotoxigenic Fusarium species in animal feed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium species are among the most studied plant pathogenic fungi, with several species causing diseases on corn, wheat, barley, and other food and feed grains. Decreased yield, as well as diminished quality and value of the grain, results in significant worldwide economic losses. Additionally, ...

  8. FUMONISIN MYCOTOXIN BIOSYNTHESIS IN FUSARIUM VERTICILLIOIDES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fumonsins are mycotoxins produced by the maize pathogen Fusarium verticillioides. These toxins are of concern because of their association with cancer in experimental rodents and the epidemiological correlation between consumption of fumonisin-contaminated maize and human esophageal cancer. We hav...

  9. HISTOLOGY AND PHYSIOLOGY OF FUSARIUM HEAD BLIGHT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight re-emerged as a devastating disease of wheat and barley in the 1990s in the midwestern U.S. Research efforts to control the disease have been hampered by limited knowledge of how the fungal head blight pathogens infect and damage head tissue and what natural defenses the plant h...

  10. Morphogenesis in germinating Fusarium graminearum macroconidia

    Microsoft Academic Search

    Steven D. Harris

    2005-01-01

    Fusarium graminearum (teleomorph Gibber- ella zeae) is a significant pathogen of wheat and corn. F. graminearum forms multicellular macroconidia that play an important role in dissemination of the disease. The spatial pattern of morphogenesis in ger- minating macroconidia is described. Germ tubes preferentially emerge from the apical cells in a bi- polar pattern that appears to be common to filamen-

  11. Identification par CGSM de l’acide phénylacétique produit par Fusarium oxysporum f. sp . albedinis, agent causal du bayoud

    Microsoft Academic Search

    T Ait Kettout; F. Rahmania

    2010-01-01

    These studies are concerned with the isolation and identification of secondary metabolites produced by Fusarium oxysporum f. sp. albedinis (F. o. a.), the causal agent of bayoud, the wilt disease of the date palm (Phoenix dactylifera L.). Fungal secondary metabolites are chemical compounds identified in a limited number of species. They consist of toxins, antibiotics and antifungal agents. Among the

  12. Molecular characterization of Fusarium oxysporum f. sp. Vasinfectum isolates recovered from cottonseed imported from Australia into California for cattle feed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bell et al. recovered 17 Fusarium oxysporum f. sp. vasinfectum (Fov) isolates from cottonseed imported from Australia into California for cattle feed in 2003. These isolates and four isolates obtained from wilted plants in Australia by Kochman in 1994 are distinct from American Fov isolates in that...

  13. Molecular characterization of Fusarium oxysporum f. sp. vasinfectum isolates from cottonseed imported from Australia into California for dairy feed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bell et al. recovered 17 Fusarium oxysporum f. sp. vasinfectum (Fov) isolates from cottonseed imported from Australia into California for dairy feed in 2003. These isolates and four isolates obtained from wilted plants in Australia by Kochman in 1994 are distinct from American Fov isolates in that ...

  14. Early Events in the Fusarium verticillioides-Maize Interaction Characterized by Using a Green Fluorescent Protein-Expressing Transgenic Isolate

    Microsoft Academic Search

    Liat Oren; Smadar Ezrati; David Cohen; Amir Sharon

    2003-01-01

    The infection of maize by Fusarium verticillioides can result in highly variable disease symptoms ranging from asymptomatic plants to severe rotting and wilting. We produced F. verticillioides green fluorescent protein- expressing transgenic isolates and used them to characterize early events in the F. verticillioides-maize inter- action that may affect later symptom appearance. Plants grown in F. verticillioides-infested soil were smaller

  15. Systemic acquired resistance in Cavendish banana induced by infection with an incompatible strain of Fusarium oxysporum f. sp. cubense.

    PubMed

    Wu, Yuanli; Yi, Ganjun; Peng, Xinxiang; Huang, Bingzhi; Liu, Ee; Zhang, Jianjun

    2013-07-15

    Fusarium wilt of banana is caused by the soil-borne fungus Fusarium oxysporum f. sp. cubense (Foc). The fact that there are no economically viable biological, chemical, or cultural measures of controlling the disease in an infected field leads to search for alternative strategies involving activation of the plant's innate defense system. The mechanisms underlying systemic acquired resistance (SAR) are much less understood in monocots than in dicots. Since systemic protection of plants by attenuated or avirulent pathogens is a typical SAR response, the establishment of a biologically induced SAR model in banana is helpful to investigate the mechanism of SAR to Fusarium wilt. This paper described one such model using incompatible Foc race 1 to induce resistance against Foc tropical race 4 in an in vitro pathosystem. Consistent with the observation that the SAR provided the highest level of protection when the time interval between primary infection and challenge inoculation was 10d, the activities of defense-related enzymes such as phenylalanine ammonia lyase (PAL, EC 4.3.1.5), peroxidase (POD, EC 1.11.1.7), polyphenol oxidase (PPO, EC 1.14.18.1), and superoxide dismutase (SOD, EC 1.15.1.1) in systemic tissues also reached the maximum level and were 2.00-2.43 times higher than that of the corresponding controls on the tenth day. The total salicylic acid (SA) content in roots of banana plantlets increased from about 1 to more than 5 ?g g?¹ FW after the second leaf being inoculated with Foc race 1. The systemic up-regulation of MaNPR1A and MaNPR1B was followed by the second up-regulation of PR-1 and PR-3. Although SA and jasmonic acid (JA)/ethylene (ET) signaling are mostly antagonistic, systemic expression of PR genes regulated by different signaling pathways were simultaneously up-regulated after primary infection, indicating that both pathways are involved in the activation of the SAR. PMID:23702248

  16. The photolyase gene from the plant pathogen Fusarium oxysporum f. sp. lycopersici is induced by visible light and alpha-tomatine from tomato plant.

    PubMed

    Alejandre-Durán, Encarna; Roldán-Arjona, Teresa; Ariza, Rafael R; Ruiz-Rubio, Manuel

    2003-11-01

    Survival of irradiated spores from Fusarium oxysporum with ultraviolet radiation (UV) was increased following exposition to visible light, indicating that this phytopathogenic fungus has a mechanism of photoreactivation able to counteract the lethal effects of UV. A genomic sequence containing the complete photolyase gene (phr1) from F. oxysporum was isolated by heterologous hybridisation with the Neurospora crassa photolyase gene. The F. oxysporum phr1 cDNA was isolated and expressed in a photolyase deficient Escherichia coli strain. The complementation of the photoreactivation deficiency of this E. coli mutant by phr1 cDNA demonstrated that the photolyase gene from F. oxysporum encodes a functional protein. The F. oxysporum PHR1 protein has a domain characteristic of photolyases from fungi (Trichoderma harziaium, N. crassa, Magnaporthe grisea, Saccharomyces cerevisiae) to bacteria (E. coli), and clusters in the photolyases phylogenetic tree with fungal photolyases. The F. oxysporum phr1 gene was inducible by visible light. The phr1 expression was also detected in presence of alpha-tomatine, a glycoalkaloid from tomato damaging cell membranes, suggesting that phr1 is induced by this cellular stress. PMID:14516768

  17. Verticillium Wilt of Shade Trees

    E-print Network

    , resulting in blockage of water movement from the roots to the foliage. The tree responds to infection recurrence of the trouble. NOTE: Yews and conifers are resistant to Verticillium wilt. Redbud and smoke tree Sassafras Boxwood Horse chestnut Serviceberry Brambles Japanese pagoda tree Smoke tree Buckeye Lilac Sumac

  18. Distribution of disease symptoms and mycotoxins in maize ears infected by Fusarium culmorum and Fusarium graminearum.

    PubMed

    Oldenburg, Elisabeth; Ellner, Frank

    2015-08-01

    Red ear rot an important disease of maize cultivated in Europe is caused by toxigenic Fusarium species like Fusarium graminearum and Fusarium culmorum. To get detailed information on the time course of the infection process leading to the accumulation of Fusarium mycotoxins in maize ears, a field study was conducted over 2 years with two maize varieties, which were inoculated with F. culmorum or F. graminearum isolates at the stage of female flowering. Every fortnight after inoculation, infection and contamination progress in the ears was followed by visually evaluating disease signs and analysing Fusarium toxin concentrations in the infected ear tissues. In principle, infection and mycotoxin distribution were similar in respect of pathogens, varieties, and years. External infection symptoms showing some small pale or brown-marbled kernels with dark brown pedicels were mainly seen at the ear tip, whereas internal infection symptoms on the rachis were much more pronounced and spread in the upper half showing greyish brownish or pink discoloration of the pith. Well correlated with disease symptoms, a top-down gradient from high to low toxin levels within the ear with considerably higher concentrations in the rachis compared with the kernels was observed. It is suggested that both Fusarium pathogens primarily infect the rachis from the tip toward the bottom, whereas the kernels are subsequently infected via the rachillae connected to the rachis. A special focus on the pronounced disease symptoms visible in the rachis may be an approach to improve the evaluation of maize-genotype susceptibility against red ear rot pathogens. It has to be underlined that the accumulation of Fusarium mycotoxins in the rachis greatly accelerated 6 weeks after inoculation; therefore, highest contamination risk is indicated for feedstuffs containing large amounts of rachis (e.g., corn cob mix), especially when cut late in growing season. PMID:25904523

  19. Expression of Baculovirus Anti-Apoptotic Genes p35 and op-iap in Cotton (Gossypium hirsutum L.) Enhances Tolerance to Verticillium Wilt

    Microsoft Academic Search

    Juan Tian; Xueyan Zhang; Benguo Liang; Shanwei Li; Zhixia Wu; Qianhua Wang; Chunxu Leng; Jiangli Dong; Tao Wang

    2010-01-01

    BackgroundProgrammed cell death plays an important role in mediating plant adaptive responses to the environment such as the invasion of pathogens. Verticillium wilt, caused by the necrotrophic pathogen Verticillium dahliae, is a serious vascular disease responsible for great economic losses to cotton, but the molecular mechanisms of verticillium disease and effective, safe methods of resistance to verticillium wilt remain unexplored.Methodology\\/Principal

  20. Field resistance to Fusarium oxysporum and Verticillium dahliae in transgenic cotton expressing the plant defensin NaD1.

    PubMed

    Gaspar, Yolanda M; McKenna, James A; McGinness, Bruce S; Hinch, Jillian; Poon, Simon; Connelly, Angela A; Anderson, Marilyn A; Heath, Robyn L

    2014-04-01

    The plant defensin NaD1, from Nicotiana alata, has potent antifungal activity against a range of filamentous fungi including the two important cotton pathogens, Fusarium oxysporum f. sp. vasinfectum (Fov) and Verticillium dahliae. Transgenic cotton plants expressing NaD1 were produced and plants from three events were selected for further characterization. Homozygous plants were assessed in greenhouse bioassays for resistance to Fov. One line (D1) was selected for field trial testing over three growing seasons in soils naturally infested with Fov and over two seasons in soils naturally infested with V. dahliae. In the field trials with Fov-infested soil, line D1 had 2-3-times the survival rate, a higher tolerance to Fov (higher disease rank), and a 2-4-fold increase in lint yield compared to the non-transgenic Coker control. When transgenic line D1 was planted in V. dahliae-infested soil, plants had a higher tolerance to Verticillium wilt and up to a 2-fold increase in lint yield compared to the non-transgenic Coker control. Line D1 did not exhibit any detrimental agronomic features compared to the parent Coker control when plants were grown in non-diseased soil. This study demonstrated that the expression of NaD1 in transgenic cotton plants can provide substantial resistance to two economically important fungal pathogens. PMID:24502957

  1. Field resistance to Fusarium oxysporum and Verticillium dahliae in transgenic cotton expressing the plant defensin NaD1

    PubMed Central

    Anderson, Marilyn A.

    2014-01-01

    The plant defensin NaD1, from Nicotiana alata, has potent antifungal activity against a range of filamentous fungi including the two important cotton pathogens, Fusarium oxysporum f. sp. vasinfectum (Fov) and Verticillium dahliae. Transgenic cotton plants expressing NaD1 were produced and plants from three events were selected for further characterization. Homozygous plants were assessed in greenhouse bioassays for resistance to Fov. One line (D1) was selected for field trial testing over three growing seasons in soils naturally infested with Fov and over two seasons in soils naturally infested with V. dahliae. In the field trials with Fov-infested soil, line D1 had 2–3-times the survival rate, a higher tolerance to Fov (higher disease rank), and a 2–4-fold increase in lint yield compared to the non-transgenic Coker control. When transgenic line D1 was planted in V. dahliae-infested soil, plants had a higher tolerance to Verticillium wilt and up to a 2-fold increase in lint yield compared to the non-transgenic Coker control. Line D1 did not exhibit any detrimental agronomic features compared to the parent Coker control when plants were grown in non-diseased soil. This study demonstrated that the expression of NaD1 in transgenic cotton plants can provide substantial resistance to two economically important fungal pathogens. PMID:24502957

  2. Gene expression profile changes in cotton root and hypocotyl tissues in response to infection with Fusarium oxysporum f. sp. vasinfectum.

    PubMed

    Dowd, Caitriona; Wilson, Iain W; McFadden, Helen

    2004-06-01

    Microarray analysis of large-scale temporal and tissue-specific plant gene expression changes occurring during a susceptible plant-pathogen interaction revealed different gene expression profile changes in cotton root and hypocotyl tissues. In hypocotyl tissues infected with Fusarium oxysporum f. sp. vasinfectum, increased expression of defense-related genes was observed, whereas few changes in the expression levels of defense-related genes were found in infected root tissues. In infected roots, more plant genes were repressed than were induced, especially at the earlier stages of infection. Although many known cotton defense responses were identified, including induction of pathogenesis-related genes and gossypol biosynthesis genes, potential new defense responses also were identified, such as the biosynthesis of lignans. Many of the stress-related gene responses were common to both tissues. The repression of drought-responsive proteins such as aquaporins in both roots and hypocotyls represents a previously unreported response of a host to pathogen attack that may be specific to vascular wilt diseases. Gene expression results implicated the phytohormones ethylene and auxin in the disease process. Biochemical analysis of hormone level changes supported this observation. PMID:15195948

  3. The two-component histidine kinase Fhk1 controls stress adaptation and virulence of Fusarium oxysporum.

    PubMed

    Rispail, Nicolas; Di Pietro, Antonio

    2010-05-01

    Fungal histidine kinases (HKs) have been implicated in different processes, such as the osmostress response, hyphal development, sensitivity to fungicides and virulence. Members of HK class III are known to signal through the HOG mitogen-activated protein kinase (MAPK), but possible interactions with other MAPKs have not been explored. In this study, we have characterized fhk1, encoding a putative class III HK from the soil-borne vascular wilt pathogen Fusarium oxysporum. Inactivation of fhk1 resulted in resistance to phenylpyrrole and dicarboximide fungicides, as well as increased sensitivity to hyperosmotic stress and menadione-induced oxidative stress. The osmosensitivity of Delta fhk1 mutants was associated with a striking and previously unreported change in colony morphology. The Delta fhk1 strains showed a significant decrease in virulence on tomato plants. Epistatic analysis between Fhk1 and the Fmk1 MAPK cascade indicated that Fhk1 does not function upstream of Fmk1, but that the two pathways may interact to control the response to menadione-induced oxidative stress. PMID:20447287

  4. Differential acquisition and transmission of Florida Tomato spotted wilt virus isolates by Western flower thrips

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thrips-vectored Tomato spotted wilt virus (TSWV) is one of the most important insect-vectored plant pathogens globally. The virus host range encompasses many key vegetable, ornamental and agronomic crops. TSWV populations are highly heterogeneous, which has important implications for vector relati...

  5. New outbreaks of verticillium wilt on Hop in Oregon caused by nonlethal verticillium albo-atrum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2006 and 2007, new outbreaks of Verticillium wilt on hop were detected on two farms in Oregon. Verticillium pathogens vary in their virulence to hop; some strains cause minor damage but others can kill susceptible cultivars. Studies were conducted to determine the identity of the Verticillium sp...

  6. Imaging O2 changes induced in tomato roots by fungal pathogen

    NASA Astrophysics Data System (ADS)

    Rubol, S.; Turco, E.; Rodeghiero, M.; Bellin, A.

    2014-12-01

    In the last decade, planar optodes have demonstrated to be a useful non-invasive tool to monitor real time oxygen concentrations in a wide range of applications. However, only limited investigations have been carried out to explore the use of optodes in plant respiration studies. In particular, their use to study plant-pathogen interactions has been not deeply investigated. Here, we present for the first time an in vitro experimental setup capable to depict the dynamical effects of the fungal pathogen Fusarium oxysporum f.sp. lycopersici (Fol) on tomato roots by the use of a recently developed optical non-invasive optode oxygen sensor (Visisens, Presens, Germany). Fol is a soil-borne pathogen and the causal agent of wilt in tomato plants, a destructive worldwide disease. The interaction Fol-tomato is widely accepted as a model system in plant pathology. In this work, oxygen concentrations are monitored continuously in time and considered a proxy for root respiration and metabolic activity. The experimental procedure reveals three different dynamic stages: 1) a uniform oxygen consumption in tomato roots earlier before pathogen colonization, 2) a progressive decrease in the oxygen concentration indicating a high metabolic activity as soon as the roots were surrounded and colonized by the fungal mycelium, and 3) absence of root respiration, as a consequence of root death. Our results suggest the ability of the fungal mycelium to move preferentially towards and along the root as a consequence of the recognition event.

  7. Isolation and characterization of an exopolygalacturonase from Fusarium oxysporum f.sp. cubense race 1 and race 4

    PubMed Central

    2011-01-01

    Background Fusarium wilt is an economically devastating disease that affects banana production. Although Cavendish banana cultivars are resistant to Fusarium oxysporum f.sp. cubense race 1 (FOC1) and maitain banana production after Gros Michel was destructed by race 1, a new race race 4 (FOC4) was found to infect Cavendish. Results An exopolygalacturonase (PGC2) was isolated and purified from the supernatant of the plant pathogen Fusarium oxysporum f.sp. cubense race 4 (FOC4). PGC2 had an apparent Mr of 63 kDa by SDS-PAGE and 51.7 kDa by mass spectrometry. The enzyme was N-glycosylated. PGC2 hydrolyzed polygalacturonic acid in an exo-manner, as demonstrated by analysis of degradation products. To obtain adequate amounts of protein for functional studies between the PGC2 proteins of two races of the pathogen, pgc2 genes encoding PGC2 from race 4 (FOC4) and race 1 (FOC1), both 1395 bp in length and encoding 465 amino acids with a predicted amino-terminal signal sequence of 18 residues, were cloned into the expression vector pPICZaA and then expressed in Pichia pastoris strains of SMD1168. The recombinant PGC2 products, r-FOC1-PGC2 and r-FOC4-PGC2, were expressed and purified as active extracellular proteins. Optimal PGC2 activity was observed at 50°C and pH 5. The Km and Vmax values of purified r-FOC1-PGC2 were 0.43 mg.mL-1 and 94.34 units mg protein-1 min-1, respectively. The Km and Vmax values of purified r-FOC4-PGC2 were 0.48 mg.mL-1 and 95.24 units mg protein-1 min-1, respectively. Both recombinant PGC2 proteins could induce tissue maceration and necrosis in banana plants. Conclusions Collectively, these results suggest that PGC2 is the first exoPG reported from the pathogen FOC, and we have shown that fully functional PGC2 can be produced in the P. pastoris expression system. PMID:21920035

  8. Environmental conditions that contribute to development and severity of Sugar Beet Fusarium Yellows caused by Fusarium oxysporum f. sp. betae: temperature

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium yellows in sugar beet, caused by Fusarium oxysporum f. sp. betae, continues to cause significant problems to sugar beet production by causing considerable reductions in root yield, sucrose percentage, and juice purity in affected sugar beets. Environment plays a critical role in pathogen i...

  9. Differentially Expressed Genes in Resistant and Susceptible Common Bean (Phaseolus vulgaris L.) Genotypes in Response to Fusarium oxysporum f. sp. phaseoli.

    PubMed

    Xue, Renfeng; Wu, Jing; Zhu, Zhendong; Wang, Lanfen; Wang, Xiaoming; Wang, Shumin; Blair, Matthew W

    2015-01-01

    Fusarium wilt of common bean (Phaseolus vulgaris L.), caused by Fusarium oxysporum Schlechtend.:Fr. f.sp. phaseoli (Fop), is one of the most important diseases of common beans worldwide. Few natural sources of resistance to Fop exist and provide only moderate or partial levels of protection. Despite the economic importance of the disease across multiple crops, only a few of Fop induced genes have been analyzed in legumes. Therefore, our goal was to identify transcriptionally regulated genes during an incompatible interaction between common bean and the Fop pathogen using the cDNA amplified fragment length polymorphism (cDNA-AFLP) technique. We generated a total of 8,730 transcript-derived fragments (TDFs) with 768 primer pairs based on the comparison of a moderately resistant and a susceptible genotype. In total, 423 TDFs (4.9%) displayed altered expression patterns after inoculation with Fop inoculum. We obtained full amplicon sequences for 122 selected TDFs, of which 98 were identified as annotated known genes in different functional categories based on their putative functions, 10 were predicted but non-annotated genes and 14 were not homologous to any known genes. The 98 TDFs encoding genes of known putative function were classified as related to metabolism (22), signal transduction (21), protein synthesis and processing (20), development and cytoskeletal organization (12), transport of proteins (7), gene expression and RNA metabolism (4), redox reactions (4), defense and stress responses (3), energy metabolism (3), and hormone responses (2). Based on the analyses of homology, 19 TDFs from different functional categories were chosen for expression analysis using quantitative RT-PCR. The genes found to be important here were implicated at various steps of pathogen infection and will allow a better understanding of the mechanisms of defense and resistance to Fop and similar pathogens. The differential response genes discovered here could also be used as molecular markers in association mapping or QTL analysis. PMID:26030070

  10. Differentially Expressed Genes in Resistant and Susceptible Common Bean (Phaseolus vulgaris L.) Genotypes in Response to Fusarium oxysporum f. sp. phaseoli

    PubMed Central

    Xue, Renfeng; Wu, Jing; Zhu, Zhendong; Wang, Lanfen; Wang, Xiaoming; Wang, Shumin; Blair, Matthew W.

    2015-01-01

    Fusarium wilt of common bean (Phaseolus vulgaris L.), caused by Fusarium oxysporum Schlechtend.:Fr. f.sp. phaseoli (Fop), is one of the most important diseases of common beans worldwide. Few natural sources of resistance to Fop exist and provide only moderate or partial levels of protection. Despite the economic importance of the disease across multiple crops, only a few of Fop induced genes have been analyzed in legumes. Therefore, our goal was to identify transcriptionally regulated genes during an incompatible interaction between common bean and the Fop pathogen using the cDNA amplified fragment length polymorphism (cDNA-AFLP) technique. We generated a total of 8,730 transcript-derived fragments (TDFs) with 768 primer pairs based on the comparison of a moderately resistant and a susceptible genotype. In total, 423 TDFs (4.9%) displayed altered expression patterns after inoculation with Fop inoculum. We obtained full amplicon sequences for 122 selected TDFs, of which 98 were identified as annotated known genes in different functional categories based on their putative functions, 10 were predicted but non-annotated genes and 14 were not homologous to any known genes. The 98 TDFs encoding genes of known putative function were classified as related to metabolism (22), signal transduction (21), protein synthesis and processing (20), development and cytoskeletal organization (12), transport of proteins (7), gene expression and RNA metabolism (4), redox reactions (4), defense and stress responses (3), energy metabolism (3), and hormone responses (2). Based on the analyses of homology, 19 TDFs from different functional categories were chosen for expression analysis using quantitative RT-PCR. The genes found to be important here were implicated at various steps of pathogen infection and will allow a better understanding of the mechanisms of defense and resistance to Fop and similar pathogens. The differential response genes discovered here could also be used as molecular markers in association mapping or QTL analysis. PMID:26030070

  11. Fusarium pathogenesis investigated using Galleria mellonella as a heterologous host

    PubMed Central

    Coleman, Jeffrey J.; Muhammed, Maged; Kasperkovitz, Pia V.; Vyas, Jatin M.; Mylonakis, Eleftherios

    2011-01-01

    Members of the fungal genus Fusarium are capable of manifesting in a multitude of clinical infections, most commonly in immunocompromised patients. In order to better understand the interaction between the fungus and host, we have developed the larvae of the greater wax moth, Galleria mellonella, as a heterologous host for fusaria. When conidia are injected into the hemocoel of this Lepidopteran system, both clinical and environmental isolates of the fungus are able to kill the larvae at 37°C, although killing occurs more rapidly when incubated at 30°C. This killing was dependent on several other factors besides temperature, including the Fusarium strain, the number of conidia injected, and the conidia morphology, where macroconidia are more virulent than their microconidia counterpart. There was a correlation in the killing rate of Fusarium spp. when evaluated in G. mellonella and a murine model. In vivo studies indicated G. mellonella hemocytes were capable of initially phagocytosing both conidial morphologies. The G. mellonella system was also used to evaluate antifungal agents, and amphotericin B was able to confer a significant increase in survival to Fusarium infected-larvae. The G. mellonella-Fusarium pathogenicity system revealed that virulence of Fusarium spp. is similar, regardless of the origin of the isolate, and that mammalian endothermy is a major deterrent for Fusarium infection and therefore provides a suitable alternative to mammalian models to investigate the interaction between the host and this increasingly important fungal pathogen. PMID:22115447

  12. Onychomycosis by Fusarium oxysporum probably acquired in utero.

    PubMed

    Carvalho, Vania O; Vicente, Vania A; Werner, Betina; Gomes, Renata R; Fornari, Gheniffer; Herkert, Patricia F; Rodrigues, Cristina O; Abagge, Kerstin T; Robl, Renata; Camiña, Ricardo H

    2014-10-01

    Fusarium oxysporum has been described as a pathogen causing onychomycosis, its incidence has been increasing in immunocompetent and disseminated infection can occur in immunosuppressed individuals. We describe the first case of congenital onychomycosis in a child caused by Fusarium oxysporum. The infection being acquired in utero was proven by molecular methods with the identification of the fungus both in the nail and placenta, most probably as an ascending contamination/infection in a HIV-positive, immunosuppressed mother. PMID:25383318

  13. Onychomycosis by Fusarium oxysporum probably acquired in utero

    PubMed Central

    Carvalho, Vania O.; Vicente, Vania A.; Werner, Betina; Gomes, Renata R.; Fornari, Gheniffer; Herkert, Patricia F.; Rodrigues, Cristina O.; Abagge, Kerstin T.; Robl, Renata; Camiña, Ricardo H

    2014-01-01

    Fusarium oxysporum has been described as a pathogen causing onychomycosis, its incidence has been increasing in immunocompetent and disseminated infection can occur in immunosuppressed individuals. We describe the first case of congenital onychomycosis in a child caused by Fusarium oxysporum. The infection being acquired in utero was proven by molecular methods with the identification of the fungus both in the nail and placenta, most probably as an ascending contamination/infection in a HIV-positive, immunosuppressed mother. PMID:25383318

  14. Inoculation of tomato seedlings with Trichoderma Harzianum and Arbuscular Mycorrhizal Fungi and their effect on growth and control of wilt in tomato seedlings.

    PubMed

    Mwangi, Margaret W; Monda, Ethel O; Okoth, Sheila A; Jefwa, Joyce M

    2011-04-01

    A green house study was conducted to investigate the ability of an isolate of Trichoderma harzianum (P52) and arbuscular mycorrhizal fungi (AMF) in enhancing growth and control of a wilt pathogen caused by Fusarium oxysporum f. sp. lycopersici in tomato seedlings. The plants were grown in plastic pots filled with sterilized soils. There were four treatments applied as follows; P52, AMF, AMF + P52 and a control. A completely randomized design was used and growth measurements and disease assessment taken after 3, 6 and 9 weeks. Treatments that significantly (P < 0.05) enhanced heights and root dry weights were P52, AMF and a treatment with a combination of both P52 and AMF when compared the control. The treatment with both P52 and AMF significantly (P < 0.05) enhanced all growth parameters (heights; shoot and root dry weight) investigated compared to the control. Disease severity was generally lower in tomato plants grown with isolate P52 and AMF fungi either individually or when combined together, though the effect was not statistically significant (P? 0.05). A treatment combination of P52 + AMF had less trend of severity as compared to each individual fungus. T. harzianum and AMF can be used to enhance growth in tomato seedlings. PMID:24031662

  15. Effects of the tomato pathogen Fusarium oxysporum f. sp. radicis-lycopersici and of the biocontrol bacterium Pseudomonas fluorescens WCS365 on the composition of organic acids and sugars in tomato root exudate.

    PubMed

    Kamilova, Faina; Kravchenko, Lev V; Shaposhnikov, Alexander I; Makarova, Nataliya; Lugtenberg, Ben

    2006-10-01

    The effects of the pathogenic fungus Fusarium oxysporum f. sp. radicis-lycopersici and of the bacterial biocontrol strain Pseudomonas fluorescens WCS365, and of both microbes, on the amounts and composition of root exudate components of tomato plants grown in a gnotobiotic stonewool substrate system were studied. Conditions were selected under which introduction of F. oxysporum f. sp. radicis-lycopersici caused severe foot and root rot, whereas inoculation of the seed with P. fluorescens WCS365 decreased the percentage of diseased plants from 96 to 7%. This is a much better disease control level than was observed in potting soil. Analysis of root exudate revealed that the presence of F. oxysporum f. sp. radicis-lycopersici did not alter the total amount of organic acids, but that the amount of citric acid decreased and that of succinic acid increased compared with the nontreated control. In contrast, in the presence of the P. fluorescens biocontrol strain WCS365, the total amount of organic acid increased, mainly due to a strong increase of the amount of citric acid, whereas the amount of succinic acid decreased dramatically. Under biocontrol conditions, when both microbes are present, the content of succinic acid decreased and the level of citric acid was similar to that in the nontreated control. The amount of sugar was approximately half that of the control sample when either one of the microbes was present alone or when both were present. Analysis of the interactions between the two microbes grown together in sterile tomato root exudate showed that WCS365 inhibited multiplication of F. oxysporum f. sp. radicis-lycopersici, whereas the fungus did not affect the number of CFU of the bacterium. PMID:17022176

  16. Fumonisin B1 accumulation and severity of fusarium ear rot and gibberella ear rot in food-grade corn hybrids in Ontario after inoculation according to two methods

    Microsoft Academic Search

    A. W. Schaafsma; L. Tamburic-Ilincic; L. M. Reid

    2006-01-01

    Fusarium verticillioides and Fusarium graminearum are pathogens of corn causing fusarium ear rot and gibberella ear rot, respectively. The mycotoxins fumonisin B1 (FB1) and deoxynivalenol (DON) are produced by F. verticillioides and F. graminearum, respectively, and commercial millers monitor the levels of these toxins in corn to avoid problems with contamination in finished foods. The objectives of the present study

  17. Progress toward breeding for Verticillium wilt resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Verticillium wilt is a persistent and serious problem in potato production. Host plant resistance offers an attractive long-term control method. Breeding progress depends on access to germplasm carrying resistance genes. This study was carried out to identify sources of Verticillium wilt resistan...

  18. Progress Toward Breeding for Verticillium Wilt Resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Verticillium wilt is a persistent and serious problem in potato production. Host plant resistance offers an attractive long-term control method. Breeding progress depends on access to germplasm carrying resistance genes. This study was carried out to identify sources of Verticillium wilt resistan...

  19. Identification of Fusarium species isolated from stored apple fruit in Croatia.

    PubMed

    Sever, Zdravka; Ivi?, Dario; Kos, Tomislav; Mili?evi?, Tihomir

    2012-12-01

    Several species of the genus Fusarium can cause apple fruit to rot while stored. Since Fusarium taxonomy is very complex and has constantly been revised and updated over the last years, the aim of this study was to identify Fusarium species from rotten apples, based on combined morphological characteristics and molecular data. We identified 32 Fusarium isolates from rotten apple fruit of cultivars Golden Delicious, Jonagold, Idared, and Pink Lady, stored in Ultra Low Oxygen (ULO) conditions. Fusarium rot was detected in 9.4 % to 33.2 % of naturally infected apples, depending on the cultivar. The symptoms were similar in all four cultivars: a soft circular brown necrosis of different extent, with or without visible sporulation. Fusarium species were identified by the morphology of cultures grown on potato-dextrose agar (PDA) and carnation leaf agar (CLA). Twenty one isolates were identified as Fusarium avenaceum and confirmed as such with polymerase chain reaction (PCR) using specific primer pair FA-ITSF and FA-ITSR. F. pseudograminearum,F. semitectum, F. crookwellense, and F. compactum were identified by morphological characteristics. F.avenaceum can produce several mycotoxins and its dominance in Fusarium rot points to the risk of mycotoxin contamination of apple fruit juices and other products for human consumption. Pathogenicity tests showed typical symptoms of Fusarium rot in most of the inoculated wounded apple fruits. In this respect Fusarium avenaceum, as the dominant cause of Fusarium rot in stored apple fruits is a typical wound parasite. PMID:23334041

  20. Evolution of a Secondary Metabolite Biosynthetic Gene Cluster in Fusarium by Gene Relocation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Trichothecenes are secondary metabolites produced by multiple genera of fungi, including some plant pathogenic species of Fusarium. Trichothecenes contribute to virulence of Fusarium on some plants and are considered to be mycotoxins because of their human and animal toxicity. Previous analyses of...

  1. FIGHTING FUSARIUM HEAD BLIGHT OF BARLEY WITH MEMBERS OF THE THIONIN GENE FAMILY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fungal pathogen Fusarium graminearum destroys barley and wheat crops in the U.S. and elsewhere by causing scab (Fusarium head blight) and depositing mycotoxins such as DON. These make the harvest unsuitable for food, feed or malting. There are no known barleys with biochemical resistance to Fusa...

  2. Npc1 is involved in sterol trafficking in the filamentous fungus Fusarium graminearum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ortholog of the human gene NPC1 was identified in the plant pathogenic, filamentous fungus Fusarium graminearum by shared amino acid sequence, protein domain structure and cellular localization of the mature fungal protein. The Fusarium Npc1 gene shares 34% amino acid sequence identity and 51% s...

  3. Characterization of Fusarium head blight (FHB) resistance and deoxynivalenol accumulation in hulled and hulless winter barley

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight (FHB), caused by Fusarium graminearum, is one of the most serious diseases impacting the U.S. barley (Hordeum vulgare L.) industry. The mycotoxin deoxynivalenol (DON) produced by the pathogen renders grain unmarketable if concentrations exceed threshold values set for end-use m...

  4. Variability in Fusarium oxysporum from sugar beets in the United States – Final Report

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium yellows can cause significant reduction in root yield, sucrose percentage and juice purity in affected sugar beets. Research in our laboratory and others on variability in Fusarium oxysporum associated with sugar beets demonstrated that isolates that are pathogenic on sugar beet can be hig...

  5. Introgression and genetic characterization of alien Fusarium head blight resistance in wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alien species are an important source of genetic variability in wheat (Triticum spp.) and carry genes for resistance to numerous pathogens, including Fusarium graminearum Schwabe, the causal agent of Fusarium head blight (FHB). The goal of this project was to develop breeder-friendly, FHB-resistant ...

  6. A MODEL WHEAT CULTIVAR FOR TRANSFORMATION TO IMPROVE RESISTANCE TO FUSARIUM HEAD BLIGHT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight (FHB), caused primarily by the fungal pathogen Fusarium graminearum, is a major disease problem in wheat (Triticum aestivum). F. graminearum infects wheat spikes from anthesis and reduces grain yield. Genetic engineering holds significant potential to aid breeders in their quest...

  7. 504 Plant Disease / Vol. 98 No. 4 Monitoring the Long-Distance Transport of Fusarium graminearum

    E-print Network

    Ross, Shane

    incidence and severity were highest when wheat followed a susceptible host (corn) and least when wheat Fusarium graminearum causes Fusarium head blight (FHB) of wheat. Little is known about dispersal graminis f. sp. tritici, causal agent of wheat stem rust (40). The atmospheric transport of plant pathogens

  8. Spatial Pattern of Verticillium dahliae Microsclerotia and Cotton Plants with Wilt Symptoms in Commercial Plantations

    PubMed Central

    Yang, Jiarong; Hu, Xiaoping; Xu, Xiangming

    2015-01-01

    Spatial patterns of pathogen inoculum in field soils and the resulting patterns of disease may reflect the underlying mechanisms of pathogen dispersal. This knowledge can be used to design more efficient sampling schemes for assessing diseases. Spatial patterns of Verticillium dahliae microsclerotia were characterized in commercial cotton fields through quadrat and point sampling in 1994 and 2013, respectively. Furthermore, cotton plants with wilt symptoms, caused by V. dahliae, were assessed in six commercial cotton fields in 2013. Soil samples were assayed for the density of microsclerotia (expressed as CFU g-1 of soil) using a wet-sieving plating method and a real-time quantitative PCR method for the 1994 and 2013 study, respectively. The estimated inoculum threshold for causing wilt development on individual plants varied with the three fields: ca. 1.6 CFU g-1 of soil for one field, and 7.2 CFU g-1 of soil for the other two. Both quadrat and point sampling spatial analyses showed that aggregation of V. dahliae inoculum in soils was usually not detected beyond 1.0 m. Similarly, the spatial patterns of wilted cotton plants indicated that spatial aggregation of diseased plants were only observed below the scale of 1.0 m in six commercial cotton plantations. Therefore, spatial aggregation of both V. dahliae inoculum and cotton plants with wilt symptoms is not likely to be detected above the scale of 1.0 m for most commercial cotton plantations. When designing schemes for assessing wilt inoculum and wilt development, this scale needs to be taken into consideration. PMID:26167868

  9. Original article Wilting effect on fermentation characteristics and

    E-print Network

    Paris-Sud XI, Université de

    Original article Wilting effect on fermentation characteristics and nutritive value of mountain the chemical characteristics and the evolution of fermentation processes in pre-wilted silages: 500 L capacity-wilting. Fermentation characteris- tics were significantly modified by wilting with an increase in pH (from 3.82 to 4

  10. Fusarium oxysporum f.sp. ciceri race 1 induced redox state alterations are coupled to downstream defense signaling in root tissues of chickpea (Cicer arietinum L.).

    PubMed

    Gupta, Sumanti; Bhar, Anirban; Chatterjee, Moniya; Das, Sampa

    2013-01-01

    Reactive oxygen species are known to play pivotal roles in pathogen perception, recognition and downstream defense signaling. But, how these redox alarms coordinate in planta into a defensive network is still intangible. Present study illustrates the role of Fusarium oxysporum f.sp ciceri Race1 (Foc1) induced redox responsive transcripts in regulating downstream defense signaling in chickpea. Confocal microscopic studies highlighted pathogen invasion and colonization accompanied by tissue damage and deposition of callose degraded products at the xylem vessels of infected roots of chickpea plants. Such depositions led to the clogging of xylem vessels in compatible hosts while the resistant plants were devoid of such obstructions. Lipid peroxidation assays also indicated fungal induced membrane injury. Cell shrinkage and gradual nuclear adpression appeared as interesting features marking fungal ingress. Quantitative real time polymerase chain reaction exhibited differential expression patterns of redox regulators, cellular transporters and transcription factors during Foc1 progression. Network analysis showed redox regulators, cellular transporters and transcription factors to coordinate into a well orchestrated defensive network with sugars acting as internal signal modulators. Respiratory burst oxidase homologue, cationic peroxidase, vacuolar sorting receptor, polyol transporter, sucrose synthase, and zinc finger domain containing transcription factor appeared as key molecular candidates controlling important hubs of the defense network. Functional characterization of these hub controllers may prove to be promising in understanding chickpea-Foc1 interaction and developing the case study as a model for looking into the complexities of wilt diseases of other important crop legumes. PMID:24058463

  11. PCR detection assays for the trichothecene-producing species Fusarium graminearum, Fusarium culmorum, Fusarium poae, Fusarium equiseti and Fusarium sporotrichioides

    Microsoft Academic Search

    Miguel Jurado; Covadonga Vázquez; Belén Patiño; M. Teresa González-Jaén

    2005-01-01

    Contamination of small-grain cereals with the fungal species Fusarium graminearum, F. culmorum, F. poae, F. sporotrichioides and F. equiseti is an important source of trichothecenes, Zearalenone and other mycotoxins which cause serious diseases in human and animals. Additionally, these species contribute to Fusarium Head Blight, a disease which produces important losses in cereal yield. Early detection and control of these

  12. New report of additional enterobacterial species causing wilt in West Bengal, India.

    PubMed

    Sarkar, Shamayeeta; Chaudhuri, Sujata

    2015-07-01

    Ralstonia solanacearum is known to be the most prominent causal agent of bacterial wilt worldwide. It has a wide host range comprising solanaceous and nonsolanaceous plants. Typical symptoms of the disease are leaf wilt, browning of vascular tissues, and collapsing of the plant. With the objective of studying the diversity of pathogens causing bacterial wilt in West Bengal, we collected samples of diseased symptomatic crops and adjacent symptomatic and asymptomatic weeds from widespread locations in West Bengal. By means of a routine molecular identification test specific to "R. solanacearum species complex", the majority of these strains (68 out of 71) were found to not be R. solanacearum. Presumptive identification of these isolates with conventional biochemicals, extensive testing of pathogenicity of a subset involving greenhouse trials fulfilling Koch's postulate test, and scanning electron microscopic analysis for the presence of pathogen in diseased plants were done. 16S rDNA sequencing of a subset of these strains (GenBank accession Nos. JX880249-JX880251) and analysis of sequences with the nBLAST programme showed a high similarity (97%-99%) to sequences of the Enterobacteriaceae group available in GenBank. Molecular phylogeny further established the taxonomic position of the strains. The 3 bacterial strain cultures have been submitted to MTCC, Institute of Microbial Technology, Chandigarh, India, and were identified as Klebsiella oxytoca, Enterobacter cowanii, and Klebsiella oxytoca, respectively. Although Enterobacter sp. has previously been reported to cause wilt in many plants, susceptibility of most of the dedicated hosts of R. solanacearum to wilt caused by Enterobacter and other bacteria from Enterobacteriaceae is being reported for the first time in this work. PMID:26040797

  13. A model for multiseasonal spread of verticillium wilt of lettuce.

    PubMed

    Wu, B M; Subbarao, K V

    2014-09-01

    Verticillium wilt, caused by Verticillium dahliae, is a destructive disease in lettuce, and the pathogen is seedborne. Even though maximum seed infestation rates of <5% have been detected in commercial lettuce seed lots, it is necessary to establish acceptable contamination thresholds to prevent introduction and establishment of the pathogen in lettuce production fields. However, introduction of inoculum into lettuce fields for experimental purposes to determine its long term effects is undesirable. Therefore, we constructed a simulation model to study the spread of Verticillium wilt following pathogen introduction from seed. The model consists of four components: the first for simulating infection of host plants, the second for simulating reproduction of microsclerotia on diseased plants, the third for simulating the survival of microsclerotia, and the fourth for simulating the dispersal of microsclerotia. The simulation results demonstrated that the inoculum density-disease incidence curve parameters and the dispersal gradients affect disease spread in the field. Although a steep dispersal gradient facilitated the establishment of the disease in a new field with a low inoculum density, a long-tail gradient allowed microsclerotia to be dispersed over greater distances, promoting the disease spread in fields with high inoculum density. The simulation results also revealed the importance of avoiding successive lettuce crops in the same field, reducing survival rate of microsclerotia between crops, and the need for breeding resistance against V. dahliae in lettuce cultivars to lower the number of microsclerotia formed on each diseased plant. The simulation results, however, suggested that, even with a low seed infestation rate, the pathogen would eventually become established if susceptible lettuce cultivars were grown consecutively in the same field for many years. A threshold for seed infestation can be established only when two of the three drivers of the disease-(i) low microsclerotia production per diseased plant, (ii) long-tail dispersal gradient, and (iii) low microsclerotia survival between lettuce crops-are present. PMID:24624952

  14. United States Department of Agriculture-Agricultural Research Service studies on polyketide toxins of Fusarium oxysporum f sp vasinfectum: potential targets for disease control.

    PubMed

    Bell, Alois A; Wheeler, Michael H; Liu, Jinggao; Stipanovic, Robert D; Puckhaber, Lorraine S; Orta, Heather

    2003-01-01

    A group of 133 isolates of the cotton wilt pathogen Fusarium oxysporum Schlecht f sp vasinfectum (Atk) Sny & Hans, representing five races and 20 vegetative compatibility groups within race 1 were used to determine the identity, biosynthetic regulation and taxonomic distribution of polyketide toxins produced by this pathogen. All isolates of F oxysporum f sp vasinfectum produced and secreted the nonaketide naphthazarin quinones, bikaverin and norbikaverin. Most isolates of race 1 (previously denoted as races 1, 2 and 6; and also called race A) also synthesized the heptaketide naphthoquinones, nectriafurone, anhydrofusarubin lactol and 5-O-methyljavanicin. Nine avirulent isolates of F oxysporum from Upland cotton roots, three isolates of race 3 of F oxysporum f sp vasinfectum, and four isolates of F oxysporum f sp vasinfectum from Australia, all of which previously failed to cause disease of Upland cotton (Gossypium hirsutum L) in stem-puncture assays, also failed to synthesize or secrete more than trace amounts of the heptaketide compounds. These results indicate that the heptaketides may have a unique role in the virulence of race 1 to Upland cotton. The synthesis of all polyketide toxins by ATCC isolate 24908 of F oxysporum f sp vasinfectum was regulated by pH, carbon/nitrogen ratios, and availability of calcium in media. Synthesis was greatest below pH 7.0 and increased progressively as carbon/nitrogen ratios were increased by decreasing the amounts of nitrogen added to media. The nonaketides were the major polyketides accumulated in synthetic media at pH 4.5 and below, whereas the heptaketides were predominant at pH 5.0 and above. The heptaketides were the major polyketides formed when 10 F oxysporum f sp vasinfectum race 1 isolates were grown on sterilized stems of Fusarium wilt-susceptible cotton cultivars, but these compounds were not produced on sorghum grain cultures. Both groups of polyketide toxins were apparently secreted by F oxysporum f sp vasinfectum, since half of the toxin in 2-day-old shake culture was present in the supernatant. Secretion was enhanced by calcium. Glutamine and glutamic acid inhibited both nonaketide and heptaketide syntheses, even at low nitrogen PMID:12846324

  15. ANALYSIS OF EXPRESSED SEQUENCE TAGS FROM GIBBERELLA ZEAE (ANAMORPH FUSARIUM GRAMINEARUM)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium graminearum is a broad host range pathogen that infects many crop plants, including wheat and barley, and causes head blight or rot diseases throughout the world. To better understand fungal development and pathogenicity in this important pathogen, we have now generated over 12,000 ESTs in...

  16. Retransformation of marker-free potato for enhanced resistance against fungal pathogens by pyramiding chitinase and wasabi defensin genes.

    PubMed

    Khan, Raham Sher; Darwish, Nader Ahmed; Khattak, Bushra; Ntui, Valentine Otang; Kong, Kynet; Shimomae, Kazuki; Nakamura, Ikuo; Mii, Masahiro

    2014-09-01

    Multi-auto-transformation vector system has been one of the strategies to produce marker-free transgenic plants without using selective chemicals and plant growth regulators and thus facilitating transgene stacking. In the study reported here, retransformation was carried out in marker-free transgenic potato CV. May Queen containing ChiC gene (isolated from Streptomyces griseus strain HUT 6037) with wasabi defensin (WD) gene (isolated from Wasabia japonica) to pyramid the two disease resistant genes. Molecular analyses of the developed shoots confirmed the existence of both the genes of interest (ChiC and WD) in transgenic plants. Co-expression of the genes was confirmed by RT-PCR, northern blot, and western blot analyses. Disease resistance assay of in vitro plants showed that the transgenic lines co-expressing both the ChiC and WD genes had higher resistance against the fungal pathogens, Fusarium oxysporum (Fusarium wilt) and Alternaria solani (early blight) compared to the non-transformed control and the transgenic lines expressing either of the ChiC or WD genes. The disease resistance potential of the transgenic plants could be increased by transgene stacking or multiple transformations. PMID:24802621

  17. Development of a real-time fluorescence loop-mediated isothermal amplification assay for rapid and quantitative detection of Fusarium oxysporum f. sp. cubense tropical race 4 in soil.

    PubMed

    Zhang, Xin; Zhang, He; Pu, Jinji; Qi, Yanxiang; Yu, Qunfang; Xie, Yixian; Peng, Jun

    2013-01-01

    Fusarium oxysporum f. sp. cubense (Foc), the causal agent of Fusarium wilt (Panama disease), is one of the most devastating diseases of banana (Musa spp.). The Foc tropical race 4 (TR4) is currently known as a major concern in global banana production. No effective resistance is known in Musa to Foc, and no effective measures for controlling Foc once banana plants have been infected in place. Early and accurate detection of Foc TR4 is essential to protect banana industry and guide banana planting. A real-time fluorescence loop-mediated isothermal amplification assay (RealAmp) was developed for the rapid and quantitative detection of Foc TR4 in soil. The detection limit of the RealAmp assay was approximately 0.4 pg/µl plasmid DNA when mixed with extracted soil DNA or 10(3) spores/g of artificial infested soil, and no cross-reaction with other relative pathogens were observed. The RealAmp assay for quantifying genomic DNA of TR4 was confirmed by testing both artificially and naturally infested samples. Quantification of the soil-borne pathogen DNA of Foc TR4 in naturally infested samples was no significant difference compared to classic real-time PCR (P>0.05). Additionally, RealAmp assay was visual with an improved closed-tube visual detection system by adding SYBR Green I fluorescent dye to the inside of the lid prior to amplification, which avoided the inhibitory effects of the stain on DNA amplification and makes the assay more convenient in the field and could thus become a simple, rapid and effective technique that has potential as an alternative tool for the detection and monitoring of Foc TR4 in field, which would be a routine DNA-based testing service for the soil-borne pathogen in South China. PMID:24376590

  18. Identification of Ina proteins from Fusarium acuminatum

    NASA Astrophysics Data System (ADS)

    Scheel, Jan Frederik; Kunert, Anna Theresa; Pöschl, Ulrich; Fröhlich-Nowoisky, Janine

    2015-04-01

    Freezing of water above -36° C is based on ice nucleation activity (INA) mediated by ice nucleators (IN) which can be of various origins. Beside mineral IN, biological particles are a potentially important source of atmospheric IN. The best-known biological IN are common plant-associated bacteria. The IN activity of these bacteria is induced by a surface protein on the outer cell membrane, which is fully characterized. In contrast, much less is known about the nature of fungal IN. The fungal genus Fusarium is widely spread throughout the earth. It belongs to the Ascomycota and is one of the most severe fungal pathogens. It can affect a variety of organisms from plants to animals including humans. INA of Fusarium was already described about 30 years ago and INA of Fusarium as well as other fungal genera is assumed to be mediated by proteins or at least to contain a proteinaceous compound. Although many efforts were made the precise INA machinery of Fusarium and other fungal species including the proteins and their corresponding genes remain unidentified. In this study preparations from living fungal samples of F. acuminatum were fractionated by liquid chromatography and IN active fractions were identified by freezing assays. SDS-page and de novo sequencing by mass spectrometry were used to identify the primary structure of the protein. Preliminary results show that the INA protein of F. acuminatum is contained in the early size exclusion chromatography fractions indicating a high molecular size. Moreover we could identify a single protein band from IN active fractions at 130-145 kDa corresponding to sizes of IN proteins from bacterial species. To our knowledge this is for the first time an isolation of a single protein from in vivo samples, which can be assigned as IN active from Fusarium.

  19. Fusarium verticillioides gene expression profiling by microarray analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides is a pathogen of maize and it can produce the toxic polyketide derived secondary metabolites called fumonisins. Fumonisins have been shown to cause animal diseases and are epidemiologically correlated to esophageal cancer and neural tube defects in humans. The genes necess...

  20. DISCONTINUOUS DISTRIBUTION OF THE FUMONISIN BIOSYNTHETIC GENE CLUSTER IN FUSARIUM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fumonisins are polyketide mycotoxins produced by Fusarium verticillioides, one of the most common ear and stalk rot pathogens of maize. Consumption of fumonisins has been associated epidemiologically with esophageal cancer in humans and experimentally with kidney and liver cancer in rodents. We us...

  1. Lignin Degradation by Fusarium solani f. sp. glycines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sudden death syndrome (SDS), caused by the soilborne fungal pathogen Fusarium solani f. sp. glycines, is one of the most important diseases of soybean. Lignin degradation may play a role in the infection, colonization, and survival of the fungus in root tissue . Lignin degradation by F. solani f. sp...

  2. RAS2 regulates growth and pathogenesis in Fusarium graminearum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium graminearum is a ubiquitous pathogen of cereal crops including wheat, barley, and maize. Diseases caused by F. graminearum are of particular concern because harvested grains are frequently contaminated with harmful mycotoxins such as deoxynivalenol (DON). Currently, little is known about ...

  3. Trehalose-related gene deletions in Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides is a widespread corn pathogen that causes root, stalk, and ear rot and produces fumonisins, toxic secondary metabolites associated with disease in livestock and humans. Our goal is to assess the feasibility of exploiting trehalose metabolism as a target for F. verticillioide...

  4. Update on Fusarium Race 4 Varietal Evaluations in California.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In recent years, differences have been noted in field situations with the fungal pathogen, Fusarium oxysporum f. sp. vas infectum (FOV), in Acala and Pima cotton in the San Joaquin Valley of California. Typically, earlier-recognized races of FOV only caused significant crop damage and yield impacts ...

  5. Interactions of Fusarium moniliforme , its metabolites and bacteria with corn

    Microsoft Academic Search

    Charles W. Bacon; Joseph W. Williamson

    1992-01-01

    Fusarium moniliforme Sheldon is an economically important pathogen of corn (Zea mays L.) which causes stalk, root and ear rot. Several mycotoxins have also been isolated, identified and implicated in both animal and human toxicoses. The fungus can be disseminated in symptomless corn seed and can also survive in crop residues in the soil. Asymptomatic infection may be related to

  6. Field performance of maize grown from Fusarium verticillioides -inoculated seed

    Microsoft Academic Search

    I. E. Yates; N. W. Widstrom; C. W. Bacon; A. Glenn; D. M. Hinton; D. Sparks; A. J. Jaworski

    2005-01-01

    Fusarium verticillioides is an important fungus occupying dual roles in the maize plant. The fungus functions as an endophyte, a fungal\\/host interaction beneficial to the growth of some plants. At other times, the fungus may function as a mycotoxin producing pathogen. The advantages and\\/or disadvantages of the endophytic relationship must be established in order to target appropriate sites for controlling

  7. Molecular biology of Fusarium mycotoxins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As the 20th century ended, Fusarium mycotoxicology entered the age of genomics. With complete genomes of Fusarium graminearum and F. verticillioides, and several Fusarium gene expression sequence databases on hand, researchers worldwide are working at a rapid pace to identify mycotoxin biosynthetic...

  8. MicroRNAs Suppress NB Domain Genes in Tomato That Confer Resistance to Fusarium oxysporum

    PubMed Central

    Ouyang, Shouqiang; Park, Gyungsoon; Atamian, Hagop S.; Han, Cliff S.; Stajich, Jason E.; Kaloshian, Isgouhi; Borkovich, Katherine A.

    2014-01-01

    MicroRNAs (miRNAs) suppress the transcriptional and post-transcriptional expression of genes in plants. Several miRNA families target genes encoding nucleotide-binding site–leucine-rich repeat (NB-LRR) plant innate immune receptors. The fungus Fusarium oxysporum f. sp. lycopersici causes vascular wilt disease in tomato. We explored a role for miRNAs in tomato defense against F. oxysporum using comparative miRNA profiling of susceptible (Moneymaker) and resistant (Motelle) tomato cultivars. slmiR482f and slmiR5300 were repressed during infection of Motelle with F. oxysporum. Two predicted mRNA targets each of slmiR482f and slmiR5300 exhibited increased expression in Motelle and the ability of these four targets to be regulated by the miRNAs was confirmed by co-expression in Nicotiana benthamiana. Silencing of the targets in the resistant Motelle cultivar revealed a role in fungal resistance for all four genes. All four targets encode proteins with full or partial nucleotide-binding (NB) domains. One slmiR5300 target corresponds to tm-2, a susceptible allele of the Tomato Mosaic Virus resistance gene, supporting functions in immunity to a fungal pathogen. The observation that none of the targets correspond to I-2, the only known resistance (R) gene for F. oxysporum in tomato, supports roles for additional R genes in the immune response. Taken together, our findings suggest that Moneymaker is highly susceptible because its potential resistance is insufficiently expressed due to the action of miRNAs. PMID:25330340

  9. Recent trends in control methods for bacterial wilt diseases caused by Ralstonia solanacearum.

    PubMed

    Yuliar; Nion, Yanetri Asi; Toyota, Koki

    2015-01-01

    Previous studies have described the development of control methods against bacterial wilt diseases caused by Ralstonia solanacearum. This review focused on recent advances in control measures, such as biological, physical, chemical, cultural, and integral measures, as well as biocontrol efficacy and suppression mechanisms. Biological control agents (BCAs) have been dominated by bacteria (90%) and fungi (10%). Avirulent strains of R. solanacearum, Pseudomonas spp., Bacillus spp., and Streptomyces spp. are well-known BCAs. New or uncommon BCAs have also been identified such as Acinetobacter sp., Burkholderia sp., and Paenibacillus sp. Inoculation methods for BCAs affect biocontrol efficacy, such as pouring or drenching soil, dipping of roots, and seed coatings. The amendment of different organic matter, such as plant residue, animal waste, and simple organic compounds, have frequently been reported to suppress bacterial wilt diseases. The combined application of BCAs and their substrates was shown to more effectively suppress bacterial wilt in the tomato. Suppression mechanisms are typically attributed to the antibacterial metabolites produced by BCAs or those present in natural products; however, the number of studies related to host resistance to the pathogen is increasing. Enhanced/modified soil microbial communities are also indirectly involved in disease suppression. New promising types of control measures include biological soil disinfection using substrates that release volatile compounds. This review described recent advances in different control measures. We focused on the importance of integrated pest management (IPM) for bacterial wilt diseases. PMID:25762345

  10. Rainfastness of Prothioconazole+Tebuconazole for Fusarium head blight and Deoxynivalenol management in soft red winter wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fungicides are most warranted for control of Fusarium head blight (FHB), a disease of wheat caused by the fungal pathogen Fusarium graminearum, when wet, rainy conditions occurs during anthesis. However, it is unclear whether rainfall directly following application affects fungicide efficacy against...

  11. Transgenic wheat carrying a barley UDP-glucosyltransferase exhibit high levels of Fusarium head blight resistance by detoxifying trichothecenes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight (FHB) is a worldwide disease of wheat and barley, mainly caused by Fusarium graminearum. During infection, the fungal pathogen produces trichothecene mycotoxins, such as deoxynivalenol (DON) and nivalenol (NIV) that increase fungal virulence. Moreover, grains contaminated with t...

  12. A Phenome-Based Functional Analysis of Transcription Factors in the Cereal Head Blight Fungus, Fusarium graminearum

    Microsoft Academic Search

    Hokyoung Son; Young-Su Seo; Kyunghun Min; Ae Ran Park; Jungkwan Lee; Jian-Ming Jin; Yang Lin; Peijian Cao; Sae-Yeon Hong; Eun-Kyung Kim; Seung-Ho Lee; Aram Cho; Seunghoon Lee; Myung-Gu Kim; Yongsoo Kim; Jung-Eun Kim; Jin-Cheol Kim; Gyung Ja Choi; Sung-Hwan Yun; Jae Yun Lim; Minkyun Kim; Yong-Hwan Lee; Yang-Do Choi; Yin-Won Lee

    2011-01-01

    Fusarium graminearum is an important plant pathogen that causes head blight of major cereal crops. The fungus produces mycotoxins that are harmful to animal and human. In this study, a systematic analysis of 17 phenotypes of the mutants in 657 Fusarium graminearum genes encoding putative transcription factors (TFs) resulted in a database of over 11,000 phenotypes (phenome). This database provides

  13. Mutations in VMK1 , a mitogen-activated protein kinase gene, affect microsclerotia formation and pathogenicity in Verticillium dahliae

    Microsoft Academic Search

    Payungsak Rauyaree; Manuel D. Ospina-Giraldo; Seogchan Kang; Ravindra G. Bhat; Krishna V. Subbarao; Sandra J. Grant; Katherine F. Dobinson

    2005-01-01

    Verticillium dahliae is an important soil-borne fungal pathogen that causes vascular wilt diseases in a large variety of important crop plants.\\u000a Due to its persistence in the soil, control of Verticillium wilt relies heavily on soil fumigation. The global ban on methyl bromide, a highly effective soil fumigant, poses an urgent\\u000a need to develop alternative control measures against Verticillium wilt;

  14. The transmembrane protein Sho1 cooperates with the mucin Msb2 to regulate invasive growth and plant infection in Fusarium oxysporum.

    PubMed

    Perez-Nadales, Elena; Di Pietro, Antonio

    2015-08-01

    In the vascular wilt pathogen Fusarium oxysporum, the mitogen-activated protein kinase (MAPK) Fmk1 is essential for plant infection. The mucin-like membrane protein Msb2 regulates a subset of Fmk1-dependent functions. Here, we examined the role of the tetraspan transmembrane protein Sho1 as an additional regulator of the Fmk1 pathway and determined its genetic interaction with Msb2. Targeted ?sho1 mutants were generated in wild-type and ?msb2 backgrounds to test possible interactions between the two genes. The mutants were examined for hyphal growth under different stress conditions, phosphorylation of the MAPK Fmk1 and an array of Fmk1-dependent virulence functions. Similar to Msb2, Sho1 was required for the activation of Fmk1 phosphorylation, as well as Fmk1-dependent gene expression and invasive growth functions, including extracellular pectinolytic activity, cellophane penetration, plant tissue colonization and virulence on tomato plants. ?sho1 mutants were hypersensitive to the cell wall-perturbing compound Calcofluor White, and this phenotype was exacerbated in the ?msb2 ?sho1 double mutant. These results highlight that Sho1 and Msb2 have partially overlapping functions upstream of the Fmk1 MAPK cascade, to promote invasive growth and plant infection, as well as cell wall integrity, in F.?oxysporum. PMID:25382187

  15. Heterokaryosis in Fusarium tricinctum and F. sporotrichioides.

    PubMed

    Cullen, D; Smalley, E B; Dimond, R L

    1983-10-01

    Heterokaryons were formed in intra- and interspecific crosses between Fusarium sporotrichioides and F. tricinctum auxotrophs. Segregant homokaryons were evaluated for trichothecene toxin production in culture. Results were consistent with nuclear control of toxin synthesis. The sexual compatibility of auxotrophs and 30 additional F. tricinctum sensu Snyder & Hansen strains was tested. Perithecial production was restricted to crosses between Florida isolates pathogenic to English ivy (Hedera helix). The linkage of several auxotrophic markers was determined by analysis of progeny of certain crosses. No T-2 toxin was produced by sexually compatible F. tricinctum isolates. PMID:6581272

  16. Identification of Molecular Markers Associated with Verticillium Wilt Resistance in Alfalfa (Medicago Sativa L.) Using High-Resolution Melting

    PubMed Central

    Zhang, Tiejun; Yu, Long-Xi; McCord, Per; Miller, David; Bhamidimarri, Suresh; Johnson, David; Monteros, Maria J.; Ho, Julie; Reisen, Peter; Samac, Deborah A.

    2014-01-01

    Verticillium wilt, caused by the soilborne fungus, Verticillium alfalfae, is one of the most serious diseases of alfalfa (Medicago sativa L.) worldwide. To identify loci associated with resistance to Verticillium wilt, a bulk segregant analysis was conducted in susceptible or resistant pools constructed from 13 synthetic alfalfa populations, followed by association mapping in two F1 populations consisted of 352 individuals. Simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers were used for genotyping. Phenotyping was done by manual inoculation of the pathogen to replicated cloned plants of each individual and disease severity was scored using a standard scale. Marker-trait association was analyzed by TASSEL. Seventeen SNP markers significantly associated with Verticillium wilt resistance were identified and they were located on chromosomes 1, 2, 4, 7 and 8. SNP markers identified on chromosomes 2, 4 and 7 co-locate with regions of Verticillium wilt resistance loci reported in M. truncatula. Additional markers identified on chromosomes 1 and 8 located the regions where no Verticillium resistance locus has been reported. This study highlights the value of SNP genotyping by high resolution melting to identify the disease resistance loci in tetraploid alfalfa. With further validation, the markers identified in this study could be used for improving resistance to Verticillium wilt in alfalfa breeding programs. PMID:25536106

  17. QTL MAPPING FOR FUSARIUM EAR ROT AND FUMONISIN CONTAMINATION RESISTANCE IN TWO POPULATIONS OF MAIZE (ZEA MAYS)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides (Sacc.) Nirenberg (synonym F. moniliforme Sheldon) (teleomorph: Gibberella moniliformis) and F. proliferatum (Matsushima) Nirenberg (teleomorph: G. intermedia) are fungal pathogens of maize (Zea mays L.) that cause ear rot and contaminate grain with fumonisins, a family of m...

  18. Plant growth hormones suppress the development of Harpophora maydis, the cause of late wilt in maize.

    PubMed

    Degani, Ofir; Drori, Ran; Goldblat, Yuval

    2015-01-01

    Late wilt, a severe vascular disease of maize caused by the fungus Harpophora maydis, is characterized by rapid wilting of maize plants before tasseling and until shortly before maturity. The pathogen is currently controlled by resistant maize cultivars, but the disease is constantly spreading to new areas. The plant's late phenological stage at which the disease appears suggests that plant hormones may be involved in the pathogenesis. This work revealed that plant growth hormones, auxin (Indole-3-acetic acid) and cytokinin (kinetin), suppress H. maydis in culture media and in a detached root assay. Kinetin, and even more auxin, caused significant suppression of fungus spore germination. Gibberellic acid did not alter colony growth rate but had a signal suppressive effect on the pathogens' spore germination. In comparison, ethylene and jasmonic acid, plant senescing and defense response regulators, had minor effects on colony growth and spore germination rate. Their associate hormone, salicylic acid, had a moderate suppressive effect on spore germination and colony growth rate, and a strong influence when combined with auxin. Despite the anti-fungal auxin success in vitro, field experiments with dimethylamine salt of  2,4-dichlorophenoxyacetic acid (that mimics the influence of auxin) failed to suppress the late wilt. The lines of evidence presented here reveal the suppressive influence of the three growth hormones studied on fungal development and are important to encourage further and more in-depth examinations of this intriguing hormonal complex regulatory and its role in the maize-H. maydis interactions. PMID:25649030

  19. A severe dieback of box elder ( Acer negundo ) caused by Fusarium solani (Mart.) Sacc. in Turkey

    Microsoft Academic Search

    E. Demirci; S. Maden

    2006-01-01

    A severe dieback has recently been observed on box elder (Acer negundo) grown on roadsides and in gardens in Ankara, the capital of Turkey. Fusarium solani was isolated from diseased box elder branches and was identified as the causal agent of dieback on this host. Pathogenicity\\u000a tests were carried out on young box elder shoots. Symptoms of the pathogen are

  20. Interactions of Bacillus mojavensis and Fusarium verticillioides with a benzoxazolinone (BOA) and its transformation product, APO.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The benzoxazolinones, specifically benzoxazolin-2(3H)-one (BOA), are important transformation products of cyclic hydroxamic acids that serve as allelochemicals, which provide resistance to maize from pathogenic bacteria and fungi, and insects. However, several maize pathogens such as Fusarium verti...

  1. Bacillus mojavensis Intensified the Accumulation of Fungitoxic APO in the Presence of Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The benzoxazolinones, specifically benzoxazolin-2(3H)-one (BOA), are important transformation products of cyclic hydroxamic acids that can serve as allelochemicals providing resistance to maize from pathogenic bacteria, fungi, and insects. However, maize pathogens such as Fusarium verticillioides a...

  2. Fine Structure of the Early Interaction of Lily Roots with Fusarium oxysporum f.sp. lilii

    Microsoft Academic Search

    R. P. Baayen; F. H. J. Rijkenberg

    1999-01-01

    The early interaction of lily roots with the cortical rot pathogen Fusarium oxysporum f.sp. lilii was studied using roots of lily bulblets grown in Hoagland's solution, inoculated with the pathogen, and sampled up to 48?h later. Conidia produced germ tubes within 6?h, which extended towards and into the mucilage covering the root elongation zone, and along and into the anticlinal

  3. Characterization and complementation of a fumonisin biosynthetic gene cluster deletion in banana isolates of Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The maize pathogen Fusarium verticillioides produces the fumonisin mycotoxins, which are of significant concern for their animal toxicity. This ascomycete is also reported from banana, but such strains do not produce fumonisins and are not pathogenic on maize seedlings. Southern analysis of several ...

  4. Identification of two tagged-insertional mutants of Fusarium graminearum impaired in asexual reproduction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium graminearum is an important fungal pathogen of small grains and maize cultivated throughout the world. This pathogen not only causes extensive crop losses due to the destructive nature of the disease but also has the ability to contaminate grains with mycotoxins. To better understand funga...

  5. Endophytic Fusarium verticillioides â??reduces disease severity caused by Ustilago maydis on maize

    Microsoft Academic Search

    Keunsub Lee; Jean J. Pan; Georgiana May

    2009-01-01

    Endophytic fungi represent diverse taxa that inhabit plant hosts without causing disease symptoms. We used endophytic isolates of Fusarium verticillioides (Sacc.) Nirenberg to understand how endophytic fungi interact with pathogens, in this case, the corn smut pathogen, Ustilago maydis DC (Corda). Endophytic F. verticillioides strains were inoculated onto maize seedlings before, simulta- neously, or after inoculation with U. maydis, and

  6. The Composition of Root Exudates from Two Different Resistant Peanut Cultivars and Their Effects on the Growth of Soil-Borne Pathogen

    PubMed Central

    Li, Xiao-gang; Zhang, Tao-lin; Wang, Xing-xiang; Hua, Ke; Zhao, Ling; Han, Zheng-min

    2013-01-01

    The high incidence of various soil-borne diseases in the monoculture field of peanut is a major production constraint in the red soil regions of southern China. The peanut root exudates are generally thought to play an important role in regulating soil-borne pathogens. The responses of the soil-borne pathogens, Fusarium oxysporum and F. solani to the peanut root exudates were studied using one susceptible cultivar Ganhua-5 (GH) and one mid-resistant cultivar Quanhua-7 (QH) as the test materials. The components and contents of the amino acids, sugars and phenolic acids in the peanut root exudates were determined. The results demonstrated that the root exudates from both susceptible and mid-resistant cultivars significantly promoted the spore germination, sporulation and mycelial growth of soil-borne pathogens, F. oxysporum, F. solani compared with the control. The extent of the stimulation was depended on the strains of the Fusarium tested, and gradually increased with the increased concentrations of peanut root exudates. HPLC analysis showed that the contents of sugars, alanine, total amino acids in the root exudates of GH were significantly higher than that in QH, whereas the contents of p-hydroxybenzoic acid, benzoic acid, p-coumaric acid and total phenolic acids were significantly lower than that in QH. Results of the study suggested that the differences in the root exudates from the different peanut cultivars were considered to regulate the wilt-resistance mechanism in the rhizosphere of peanut. The results are therefore crucial important to illustrate the mechanism of peanut replanted obstacle, and to develop its control techniques in the red soil regions of southern China. PMID:23412138

  7. Two rhizobacterial strains, individually and in interactions with Rhizobium sp., enhance fusarial wilt control, growth, and yield in pigeon pea.

    PubMed

    Dutta, Swarnalee; Morang, Pranjal; Kumar S, Nishanth; Dileep Kumar, B S

    2014-09-01

    A Pseudomonas aeruginosa strain, RRLJ 04, and a Bacillus cereus strain, BS 03, were tested both individually and in combination with a Rhizobium strain, RH 2, for their ability to enhance plant growth and nodulation in pigeon pea (Cajanus cajan L.) under gnotobiotic, greenhouse and field conditions. Both of the rhizobacterial strains exhibited a positive effect on growth in terms of shoot height, root length, fresh and dry weight, nodulation and yield over the non-treated control. Co-inoculation of seeds with these strains and Rhizobium RH 2 also reduced the number of wilted plants, when grown in soil infested with Fusarium udum. Gnotobiotic studies confirmed that the suppression of wilt disease was due to the presence of the respective PGPR strains. Seed bacterization with drug-marked mutants of RRLJ 04 and BS 03 confirmed their ability to colonize and multiply along the roots. The results suggest that co-inoculation of these strains with Rhizobium strain RH 2 can be further exploited for enhanced growth, nodulation and yield in addition to control of fusarial wilt in pigeon pea. PMID:25224506

  8. Isolation of Bacillus amyloliquefaciens S20 and its application in control of eggplant bacterial wilt.

    PubMed

    Chen, Da; Liu, Xin; Li, Chunyu; Tian, Wei; Shen, Qirong; Shen, Biao

    2014-05-01

    Bacterial strain S20 was isolated and identified as Bacillus amyloliquefaciens based on physiological and biochemical characteristics and a 16S rRNA gene sequence analysis. Strain S20 inhibits the growth of Fusarium oxysporum and Ralstonia solanacearum. Some genes associated with the synthesis of some lipopeptides were detected in strain S20 by PCR. Iturins A were identified as the main antagonistic substrates by analysis with electrospray ionization mass spectrometry/collision-induced dissociation (ESI-MS/CID). Four homologues of iturin A (C13-C16) were identified. Pot experiments showed that the application of strain S20 alone could control eggplant wilt with an efficacy of 25.3% during a 40 day experiment. If strain S20 was used with organic fertilizer, the control efficacy against eggplant wilt reached as high as 70.7%. The application of organic fertilizer alone promotes the growth of R. solanacearum, resulting in a higher wilt incidence than that observed in control plants. The application of strain S20 effectively inhibits R. solanacearum in the rhizosphere soil of eggplant. The combined use of strain S20 and organic fertilizer more effectively controlled R. solanacearum in soil than the use of strain S20 alone. The soil count of strain S20 decreased gradually during the course of the experiment after inoculation. Organic fertilizer was beneficial for the survival of the antagonistic bacterial strain S20; a higher level of these bacteria could be maintained. The application of organic fertilizer with strain S20 increased bacterial diversity in rhizosphere soil. PMID:24632400

  9. Eugenol oil nanoemulsion: antifungal activity against Fusarium oxysporum f. sp. vasinfectum and phytotoxicity on cottonseeds

    NASA Astrophysics Data System (ADS)

    Abd-Elsalam, Kamel A.; Khokhlov, Alexei R.

    2015-02-01

    The current research deals with the formulation and characterization of bio-based oil-in-water nanoemulsion. The formulated eugenol oil nanoemulsion was characterized by dynamic light scattering, stability test, transmission electron microscopy and thin layer chromatography. The nanoemulsion droplets were found to have a Z-average diameter of 80 nm and TEM study reveals the spherical shape of eugenol oil nanoemulsion (EON). The size of the nanoemulsion was found to be physically stable up to more than 1-month when it was kept at room temperature (25 °C). The TEM micrograph showed that the EON was spherical in shape and moderately mono or di-dispersed and was in the range of 50-110 nm. Three concentrations of the nanoformulation were used to evalute the anti-fusarium activity both in vitro and in vivo experiments. SDS-PAGE results of total protein from the Fusarium oxysporum f. sp. vasinfectum (FOV) isolate before and after treatment with eugenol oil nanoemulsion indicate that the content of extra cellular soluble small molecular proteins decreased significantly in EON-treated fungus. Light micrographs of mycelia and spores treated with EON showed the disruption of the fungal structures. The analysis of variance (ANOVA) for Fusarium wilt incidence indicated highly significant ( p = 0.000) effects of concentration, genotype, and their interaction. The difference in wilt incidence between concentrations and control was not the same for each genotype, that is, the genotypes responded differently to concentrations. Effects of three EON concentration on germination percentage, and radicle length, were determined in the laboratory. One very interesting finding in the current study is that cotton genotypes was the most important factors in determining wilt incidence as it accounted for 93.18 % of the explained (model) variation. In vitro experiments were conducted to evaluate the potential phytotoxic effect of three EON concentrations. Concentration, genotype and concentration x genotype interaction were all highly significant sources of variation in seed germination; however, interaction was the first in importance as a source of variation followed by the concentration, while genotype was the least important source of variation. These results suggest the potential use of eugenol oil nanoemulsion for protecting seedcotton from Fusarium wilt infection.

  10. Prussin et. al. 1 Agricultural and Forest Meteorology Experimental Validation of a Long-Distance Transport Model for Plant Pathogens:1

    E-print Network

    Ross, Shane

    -Distance Transport Model for Plant Pathogens:1 Application to Fusarium graminearum2 Aaron J. Prussin, II1* , Linsey C, causal agent of Fusarium head blight (FHB) of wheat and barley,24 is a devastating plant pathogen developed to predict the long distance26 transport of plant pathogens, but this model has not yet been

  11. Can vessel dimension explain tolerance toward fungal vascular wilt diseases in woody plants? Lessons from Dutch elm disease and esca disease in grapevine.

    PubMed

    Pouzoulet, Jérôme; Pivovaroff, Alexandria L; Santiago, Louis S; Rolshausen, Philippe E

    2014-01-01

    This review illuminates key findings in our understanding of grapevine xylem resistance to fungal vascular wilt diseases. Grapevine (Vitis spp.) vascular diseases such as esca, botryosphaeria dieback, and eutypa dieback, are caused by a set of taxonomically unrelated ascomycete fungi. Fungal colonization of the vascular system leads to a decline of the plant host because of a loss of the xylem function and subsequent decrease in hydraulic conductivity. Fungal vascular pathogens use different colonization strategies to invade and kill their host. Vitis vinifera cultivars display different levels of tolerance toward vascular diseases caused by fungi, but the plant defense mechanisms underlying those observations have not been completely elucidated. In this review, we establish a parallel between two vascular diseases, grapevine esca disease and Dutch elm disease, and argue that the former should be viewed as a vascular wilt disease. Plant genotypes exhibit differences in xylem morphology and resistance to fungal pathogens causing vascular wilt diseases. We provide evidence that the susceptibility of three commercial V. vinifera cultivars to esca disease is correlated to large vessel diameter. Additionally, we explore how xylem morphological traits related to water transport are influenced by abiotic factors, and how these might impact host tolerance of vascular wilt fungi. Finally, we explore the utility of this concept for predicting which V. vinifera cultivars are most vulnerable of fungal vascular wilt diseases and propose new strategies for disease management. PMID:24971084

  12. Selection for resistance to Verticillium wilt caused by race 2 isolates of Verticillium dahliae in accessions of lettuce (Lactuca sativa L.).

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Verticillium wilt of lettuce caused by Verticillium dahliae can cause severe economic damage to lettuce producers. The pathogen exists as two races (races 1 and 2) in lettuce, and complete resistance to race 1 is known. Resistance to race 2 isolates has not been reported, and production of race 1 re...

  13. THE DEVELOPMENT AND IMPACT OF VERTICILLIUM WILT ON POST-HARVEST QUALITY IN COMMERCIAL LETTUCE FIELDS NATURALLY INFESTED WITH V. DAHLIAE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Verticillium wilt of lettuce, caused by the soilborne pathogen V. dahliae, poses a serious threat to California’s $1.5 billion lettuce industry, as the acreage affected by the disease increases steadily in coastal production areas. Knowledge of disease development and its impact on post-harve...

  14. Entomopathogenic fungi as a biological control agents for the vector of the laurel wilt disease, the redbay ambrosia beetle, Xyleborus glabratus (Coleoptera: Curculionidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The redbay ambrosia beetle (RAB), Xyleborus glabratus (Coleoptera: Curculionidae: Scolytinae) vectors the fungal pathogen, Raffaelea lauricola, which causes laurel wilt (LW), a lethal disease of trees in the family Lauraceae, including the most commercially important crop in this family, avocado, Pe...

  15. Evaluation of commercial formulations of entomopathogenic fungi to manage the redbay ambrosia beetle, vector of Laurel wilt, a lethal disease affecting avocados in Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The redbay ambrosia beetle (RAB), Xyleborus glabratus (Coleoptera: Curculionidae: Scolytinae) vectors the fungal pathogen, Raffaelea lauricola, which causes laurel wilt (LW), a lethal disease of trees in the family Lauraceae, including the most commercially important crop in this family, avocado, Pe...

  16. [Invasive fungal disease due to Scedosporium, Fusarium and mucorales].

    PubMed

    Pemán, Javier; Salavert, Miguel

    2014-01-01

    The number of emerging organisms causing invasive fungal infections has increased in the last decades. These etiological agents include Scedosporium, Fusarium and mucorales. All of them can cause disseminated, virulent, and difficult-to treat infections in immunosuppressed patients, the most affected, due to their resistance to most available antifungal agents. Current trends in transplantation including the use of new immunosuppressive treatments, the common prescription of antifungal agents for prophylaxis, and new ecological niches could explain the emergence of these fungal pathogens. These pathogens can also affect immunocompetent individuals, especially after natural disasters (earthquakes, floods, tsunamis), combat wounds or near drowning. All the invasive infections caused by Scedosporium, Fusarium, and mucorales are potentially lethal and a favourable outcome is associated with rapid diagnosis by direct microscopic examination of the involved tissue, wide debridement of infected material, early use of antifungal agents including combination therapy, and an improvement in host defenses, especially neutropenia. PMID:25442383

  17. Modification of competence for in vitro response to Fusarium oxysporum in tomato cells. II. Effect of the integration of Agrobacterium tumefaciens genes for auxin and cytokinin synthesis

    Microsoft Academic Search

    E. Storti; P. Bogani; P. Bettini; P. Bittini; M. L. Guardiola; M. G. Pellegrini; D. Inzé; M. Buiatti

    1994-01-01

    We have studied the effect of a change in the endogenous hormone equilibria on the competence of tomato (Lycopersicon esculentum) cells to defend themselves against the fungal pathogen Fusarium oxysporum f. sp. lycopersici. Calluses from cvs ‘Davis’ and ‘Red River’, respectively resistant and susceptible to Fusarium and transgenic for an auxin- or cytokinin-synthesizing gene from Agrobacterium tumefaciens, were used. The

  18. Effect of Fusarium Head Blight on Hard Red Spring Wheat Quality and Correlation with Accumulation of the Toxin Deoxynivalenol in the Grain After Fungicide Treatment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    1. Fusarium head blight (FHB) is a fungal disease that negatively affects small grains. In wheat this is caused by the pathogen Fusarium graminearum. An important effect of FHB infection is the production of several toxins including deoxynivalenol (DON) also referred to as vomitoxin. The Food and Dr...

  19. PCR detection assays for the trichothecene-producing species Fusarium graminearum, Fusarium culmorum, Fusarium poae, Fusarium equiseti and Fusarium sporotrichioides.

    PubMed

    Jurado, Miguel; Vázquez, Covadonga; Patiño, Belén; González-Jaén, M Teresa

    2005-08-01

    Contamination of small-grain cereals with the fungal species Fusarium graminearum, F. culmorum, F. poae, F. sporotrichioides and F. equiseti is an important source of trichothecenes, Zearalenone and other mycotoxins which cause serious diseases in human and animals. Additionally, these species contribute to Fusarium Head Blight, a disease which produces important losses in cereal yield. Early detection and control of these Fusarium species is crucial to prevent toxins entering the food chain and a useful tool in disease management practices. We describe the development of specific PCR assays to F. graminearum, F. culmorum, F. poae, F. sporotrichioides and F. equiseti using DNA from pure fungal cultures as well as from naturally infected wheat seeds, using in this case a rapid and easy protocol for DNA isolation. The specific primers were designed on the basis of IGS sequences (Intergenic Spacer of rDNA), a multicopy region in the genome that permits to enhance the sensitivity of the assay in comparison with PCR assays based on single-copy sequences. PMID:16104354

  20. Incidences and severity of vascular wilt in Acacia mangium plantations in Sabah, Malaysia

    NASA Astrophysics Data System (ADS)

    Maid, Mandy; Ratnam, Wickneswari

    2014-09-01

    This study aimed to evaluate the incidences and severity of vascular wilt disease associated with dieback in stands of commercial Acacia mangium plantations. The study revealed that the prevalence of the symptoms is high between 50 to 60% in two plantations, where it is found scattered in the plots that were surveyed. The incidence of the disease in each plot is low between 0 to 6%. The disease symptoms were more often found where the symptom syndrome in a chronic (level 3) or critical state (level 4). This suggests that the causal pathogen has the ability to penetrate into the tissues of the plants and only display symptoms at the latest stage.

  1. Agrobacterium-mediated transformation of tomato with rolB gene results in enhancement of fruit quality and foliar resistance against fungal pathogens.

    PubMed

    Arshad, Waheed; Haq, Ihsan-ul-; Waheed, Mohammad Tahir; Mysore, Kirankumar S; Mirza, Bushra

    2014-01-01

    Tomato (Solanum lycopersicum L.) is the second most important cultivated crop next to potato, worldwide. Tomato serves as an important source of antioxidants in human diet. Alternaria solani and Fusarium oxysporum cause early blight and vascular wilt of tomato, respectively, resulting in severe crop losses. The foremost objective of the present study was to generate transgenic tomato plants with rolB gene and evaluate its effect on plant morphology, nutritional contents, yield and resistance against fungal infection. Tomato cv. Rio Grande was transformed via Agrobacterium tumefaciens harbouring rolB gene of Agrobacterium rhizogenes. rolB. Biochemical analyses showed considerable improvement in nutritional quality of transgenic tomato fruits as indicated by 62% increase in lycopene content, 225% in ascorbic acid content, 58% in total phenolics and 26% in free radical scavenging activity. Furthermore, rolB gene significantly improved the defence response of leaves of transgenic plants against two pathogenic fungal strains A. solani and F. oxysporum. Contrarily, transformed plants exhibited altered morphology and reduced fruit yield. In conclusion, rolB gene from A. rhizogenes can be used to generate transgenic tomato with increased nutritional contents of fruits as well as improved foliar tolerance against fungal pathogens. PMID:24817272

  2. Agrobacterium-Mediated Transformation of Tomato with rolB Gene Results in Enhancement of Fruit Quality and Foliar Resistance against Fungal Pathogens

    PubMed Central

    Arshad, Waheed; Haq, Ihsan-ul-; Waheed, Mohammad Tahir; Mysore, Kirankumar S.; Mirza, Bushra

    2014-01-01

    Tomato (Solanum lycopersicum L.) is the second most important cultivated crop next to potato, worldwide. Tomato serves as an important source of antioxidants in human diet. Alternaria solani and Fusarium oxysporum cause early blight and vascular wilt of tomato, respectively, resulting in severe crop losses. The foremost objective of the present study was to generate transgenic tomato plants with rolB gene and evaluate its effect on plant morphology, nutritional contents, yield and resistance against fungal infection. Tomato cv. Rio Grande was transformed via Agrobacterium tumefaciens harbouring rolB gene of Agrobacterium rhizogenes. rolB. Biochemical analyses showed considerable improvement in nutritional quality of transgenic tomato fruits as indicated by 62% increase in lycopene content, 225% in ascorbic acid content, 58% in total phenolics and 26% in free radical scavenging activity. Furthermore, rolB gene significantly improved the defence response of leaves of transgenic plants against two pathogenic fungal strains A. solani and F. oxysporum. Contrarily, transformed plants exhibited altered morphology and reduced fruit yield. In conclusion, rolB gene from A. rhizogenes can be used to generate transgenic tomato with increased nutritional contents of fruits as well as improved foliar tolerance against fungal pathogens. PMID:24817272

  3. Differentially Expressed Proteins Associated with Fusarium Head Blight Resistance in Wheat

    PubMed Central

    Zhang, Xianghui; Fu, Jianming; Hiromasa, Yasuaki; Pan, Hongyu; Bai, Guihua

    2013-01-01

    Background Fusarium head blight (FHB), mainly caused by Fusarium graminearum, substantially reduces wheat grain yield and quality worldwide. Proteins play important roles in defense against the fungal infection. This study characterized differentially expressed proteins between near-isogenic lines (NILs) contrasting in alleles of Fhb1, a major FHB resistance gene in wheat, to identify proteins underlining FHB resistance of Fhb1. Methods The two-dimensional protein profiles were compared between the Fusarium-inoculated spikes of the two NILs collected 72 h after inoculation. The protein profiles of mock- and Fusarium-inoculated Fhb1+NIL were also compared to identify pathogen-responsive proteins. Results Eight proteins were either induced or upregulated in inoculated Fhb1+NIL when compared with mock-inoculated Fhb1+NIL; nine proteins were either induced or upregulated in the Fusarium-inoculated Fhb1+NIL when compared with Fusarium-inoculated Fhb1?NIL. Proteins that were differentially expressed in the Fhb1+NIL, not in the Fhb1?NIL, after Fusarium inoculation included wheat proteins for defending fungal penetration, photosynthesis, energy metabolism, and detoxification. Conclusions Coordinated expression of the identified proteins resulted in FHB resistance in Fhb1+NIL. The results provide insight into the pathway of Fhb1-mediated FHB resistance. PMID:24376514

  4. Ralstonia solanacearum Extracellular Polysaccharide Is a Specific Elicitor of Defense Responses in Wilt-Resistant Tomato Plants

    PubMed Central

    Milling, Annett; Babujee, Lavanya; Allen, Caitilyn

    2011-01-01

    Ralstonia solanacearum, which causes bacterial wilt of diverse plants, produces copious extracellular polysaccharide (EPS), a major virulence factor. The function of EPS in wilt disease is uncertain. Leading hypotheses are that EPS physically obstructs plant water transport, or that EPS cloaks the bacterium from host plant recognition and subsequent defense. Tomato plants infected with R. solanacearum race 3 biovar 2 strain UW551 and tropical strain GMI1000 upregulated genes in both the ethylene (ET) and salicylic acid (SA) defense signal transduction pathways. The horizontally wilt-resistant tomato line Hawaii7996 activated expression of these defense genes faster and to a greater degree in response to R. solanacearum infection than did susceptible cultivar Bonny Best. However, EPS played different roles in resistant and susceptible host responses to R. solanacearum. In susceptible plants the wild-type and eps? mutant strains induced generally similar defense responses. But in resistant Hawaii7996 tomato plants, the wild-type pathogens induced significantly greater defense responses than the eps? mutants, suggesting that the resistant host recognizes R. solanacearum EPS. Consistent with this idea, purified EPS triggered significant SA pathway defense gene expression in resistant, but not in susceptible, tomato plants. In addition, the eps? mutant triggered noticeably less production of defense-associated reactive oxygen species in resistant tomato stems and leaves, despite attaining similar cell densities in planta. Collectively, these data suggest that bacterial wilt-resistant plants can specifically recognize EPS from R. solanacearum. PMID:21253019

  5. Antagonistic effect of two isolates of Trichoderma harzianum against postharvest pathogens of tomato (Lycopersicon esculentum)

    Microsoft Academic Search

    Momein H. El-Katatny; Mohamed S. El-Katatny; Ezat M. Fadl-Allah; Abeer S. Emam

    2011-01-01

    Pathogenicity test of all fungi (14 different isolates) isolated from both infected tomato fruits and the surface wash of other healthy fruits had different pathogenicity rates. The genus Rhizopus sp. was the most pathogenic one followed by Fusarium sp. Trichoderma harzianum isolates (T3 and T4) had a different pattern of antagonism against the tested pathogens. In dual plate test of

  6. Metabolic profiling of chickpea-Fusarium interaction identifies differential modulation of disease resistance pathways.

    PubMed

    Kumar, Yashwant; Dholakia, Bhushan B; Panigrahi, Priyabrata; Kadoo, Narendra Y; Giri, Ashok P; Gupta, Vidya S

    2015-08-01

    Chickpea is the third most widely grown legume in the world and mainly used as a vegetarian source of human dietary protein. Fusarium wilt, caused by Fusarium oxysporum f. sp. ciceri (Foc), is one of the major threats to global chickpea production. Host resistance is the best way to protect crops from diseases; however, in spite of using various approaches, the mechanism of Foc resistance in chickpea remains largely obscure. In the present study, non-targeted metabolic profiling at several time points of resistant and susceptible chickpea cultivars using high-resolution liquid chromatography-mass spectrometry was applied to better understand the mechanistic basis of wilt resistance or susceptibility. Multivariate analysis of the data (OPLS-DA) revealed discriminating metabolites in chickpea root tissue after Foc inoculation such as flavonoids, isoflavonoids, alkaloids, amino acids and sugars. Foc inoculated resistant plants had more flavonoids and isoflavonoids along with their malonyl conjugates. Many antifungal metabolites that were induced after Foc infection viz., aurantion-obstine ?-glucosides and querecitin were elevated in resistant cultivar. Overall, diverse genetic and biochemical mechanisms were operational in the resistant cultivar for Foc defense as compared to the susceptible plant. The resistant chickpea plants employed the above-mentioned metabolic pathways as potential defense strategy against Foc. PMID:25935544

  7. Mycoses of wheat stem sawfly (Hymenoptera: Cephidae) larvae by Fusarium spp. isolates.

    PubMed

    Wenda-Piesik, Anna; Sun, Zhitan; Grey, William E; Weaver, David K; Morrill, Wendell L

    2009-04-01

    A complex of Fusarium spp., including F. pseudograminearum, F. culmorum, F. avenaceum, F. equiseti, and F. acuminatum, was isolated from field-collected larval cadavers of wheat stem sawfly at two locations for 2 yr. The Fusarium spp. isolates caused mortality in both diapausing larvae in a topical bioassay and in developing larvae feeding in infected stems in a greenhouse experiment. Larval mortality was >90% in both experiments at the highest dose. The pattern of correlation between integument discoloration, hyphal growth, and larval mortality showed that the Fusarium spp. isolates actively infect larvae and kill them, rather than colonizing larval tissue as secondary postmortem invaders. The versatility of Fusarium spp. as plant and insect pathogens enables colonization that results in disease in wheat plants and subsequent mortality of the wheat stem sawfly larvae developing within the same tissue. PMID:19389287

  8. Nuclear Magnetic Resonance (NMR) studies on the biosynthesis of fusaric acid from Fusarium oxysporum f. sp. vasinfectum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium oxysporum is a fungal pathogen that attacks many economically important plants. Uniquely pathogenic strains of F. oxysporum f. sp. vasinfectum were inadvertently imported into the United States on live cottonseed for dairy cattle feed. These strains produce exceptionally high concentratio...

  9. Pathogenesis in Pine Wilt Caused by Pinewood Nematode, Bursaphelenchus xylophilus

    PubMed Central

    Myers, Ronald F.

    1988-01-01

    The progression of events in the development of pine wilt disease following the invasion by Bursaphelenchus xylophilus is reviewed from early migration through pine tissues until symptom development on foliage. Disease resistance in pines, especially the hypersensitive reaction that is successful in controlling many potential pests and pathogens, is explored. Pathologies resulting from the activities of pinewood nematode include cortical trails and cavities; formation of cambial gaps and traumatic resin cysts; browning and death of cortex, phloem, cambium, and ray tissues; granulation and shrinkage of cell cytoplasm in rays; and destruction of resin canal epithelial and ray parenchyma cells. Death of parenchyma, production of toxins, and leakage of oleoresins and other material into tracheids are typical of the hypersensitive reaction occurring in pines following migration of small numbers of pinewood nematodes. The hypothesis presented is that a spreading hypersensitive reaction results in some of the observed pathologies and symptoms and eventually causes pine death. The growth-differentiation balance hypothesis is used to help explain predisposition, oleoresin production and toxicity, susceptibility and resistance, and the effects of variation in climate on host pines as related to pinewilt disease. PMID:19290207

  10. Fusarium species from the cassava root rot complex in west Africa.

    PubMed

    Bandyopadhyay, Ranajit; Mwangi, Maina; Aigbe, Sylvester O; Leslie, John F

    2006-06-01

    ABSTRACT Fusarium species are a significant component of the set of fungi associated with cassava root rot. Yield losses due to root rot average 0.5 to 1 ton/ha but losses >3 ton/ha, an equivalent of 15 to 20% yield, often occur. This paper reviews previous work on cassava root rot and summarizes a few recent studies on Fusarium species associated with the disease. Our studies in Cameroon showed that 30% of rotted tubers were infected by Fusarium spp. 12 months after planting and represented 25% of all the fungal isolates recovered. Other commonly recovered fungi were Botryodiplodia theobromae and Armillaria spp. Numerous and diverse species of Fusarium were associated with rotted cassava roots in Nigeria and Cameroon. At least 13 distinct amplified fragment length polymorphism (AFLP) groups of Fusarium were distinguishable, each group probably a distinct species, and many of them might represent previously undescribed Fusarium species. The two largest of the AFLP groups correspond to F. oxysporum and F. solani species complex. The distribution of Fusarium spp. varied among countries and among locations within a country, suggesting that germ plasm resistant at one location may not be resistant at another. Fusarium spp. also cause seedling blight of cassava and can be recovered from the stems of infected plants up to 1 m above the ground. Therefore, the pathogen can spread with stems cut as planting material. Fusarium spp. also can colonize Chromolaena odorata, the dominant weed in short fallows, which could further complicate management efforts by serving as an alternative host for strains that colonize cassava. PMID:18943189

  11. Genome regions' putative association with Fusarium wilt or root-knot nematode resistance in cotton.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Around 1,300 microsatellite or SSR markers [named MUSB001 – MUSB1316 (600 informative)] were developed at the USDA-ARS, WICSRU Shafter, CA with the support of cooperators and Cotton Incorporated. These MUSB markers were developed from BAC-end DNA sequence information from a previously developed BAC ...

  12. An easy and efficient protocol in the production of pflp transgenic banana against Fusarium wilt

    Microsoft Academic Search

    Mei-Kuen Yip; Sin-Wan Lee; Kuei-Ching Su; Yi-Hsien Lin; Tai-Yang Chen; Teng-Yung Feng

    2011-01-01

    This study describes an efficient protocol for Agrobacterium tumefaciens-mediated transformation of two subgroups of genotype AAA bananas (Musa acuminata cv. Pei Chiao and Musa acuminata cv. Gros Michel). Instead of using suspension cells, cauliflower-like bud clumps, also known as multiple bud clumps (MBC),\\u000a were induced from sucker buds on MS medium containing N\\u000a 6-Benzylaminopurine (BA), Thidiazuron (TDZ), and Paclobutrazol (PP333).

  13. Bacterial wilt resistance in tomato, pepper, and eggplant: genetic resources respond to diverse strains in the Ralstonia solanacearum species complex.

    PubMed

    Lebeau, A; Daunay, M-C; Frary, A; Palloix, A; Wang, J-F; Dintinger, J; Chiroleu, F; Wicker, E; Prior, P

    2011-01-01

    Bacterial wilt, caused by strains belonging to the Ralstonia solanacearum species complex, inflicts severe economic losses in many crops worldwide. Host resistance remains the most effective control strategy against this disease. However, wilt resistance is often overcome due to the considerable variation among pathogen strains. To help breeders circumvent this problem, we assembled a worldwide collection of 30 accessions of tomato, eggplant and pepper (Core-TEP), most of which are commonly used as sources of resistance to R. solanacearum or for mapping quantitative trait loci. The Core-TEP lines were challenged with a core collection of 12 pathogen strains (Core-Rs2) representing the phylogenetic diversity of R. solanacearum. We observed six interaction phenotypes, from highly susceptible to highly resistant. Intermediate phenotypes resulted from the plants' ability to tolerate latent infections (i.e., bacterial colonization of vascular elements with limited or no wilting). The Core-Rs2 strains partitioned into three pathotypes on pepper accessions, five on tomato, and six on eggplant. A "pathoprofile" concept was developed to characterize the strain clusters, which displayed six virulence patterns on the whole set of Core-TEP host accessions. Neither pathotypes nor pathoprofiles were phylotype specific. Pathoprofiles with high aggressiveness were mainly found in strains from phylotypes I, IIB, and III. One pathoprofile included a strain that overcame almost all resistance sources. PMID:20795852

  14. Moths that Vector a Plant Pathogen also Transport Endophytic Fungi and Mycoparasitic Antagonists

    Microsoft Academic Search

    Tracy S. Feldman; Heath E. O’Brien; A. Elizabeth Arnold

    2008-01-01

    Claviceps paspali, a common fungal pathogen of Paspalum grasses, attracts moth vectors by producing sugary exudates in the grass florets it infects. These exudates also support\\u000a mycoparasitic Fusarium species that may negatively influence C. paspali fitness. We examined the potential for moths on which C. paspali depends to also transmit mycoparasitic Fusarium and fungal endophytes, which inhabit asymptomatic plant tissue

  15. Degradation of pathogen quorum-sensing molecules by soil bacteria: a preventive and curative biological control mechanism.

    PubMed

    Molina, Lázaro; Constantinescu, Florica; Michel, Laurent; Reimmann, Cornelia; Duffy, Brion; Défago, Geneviève

    2003-07-01

    Abstract The plasmid pME6863, carrying the aiiA gene from the soil bacterium Bacillus sp. A24 that encodes a lactonase enzyme able to degrade N-acyl-homoserine lactones (AHLs), was introduced into the rhizosphere isolate Pseudomonas fluorescens P3. This strain is not an effective biological control agent against plant pathogens. The transformant P. fluorescens P3/pME6863 acquired the ability to degrade AHLs. In planta, P. fluorescens P3/pME6863 significantly reduced potato soft rot caused by Erwinia carotovora and crown gall of tomato caused by Agrobacterium tumefaciens to a similar level as Bacillus sp. A24. Little or no disease reduction was observed for the wild-type strain P3 carrying the vector plasmid without aiiA. Suppression of potato soft rot was observed even when the AHL-degrading P. fluorescens P3/pME6863 was applied to tubers 2 days after the pathogen, indicating that biocontrol was not only preventive but also curative. When antagonists were applied individually with the bacterial plant pathogens, biocontrol activity of the AHL degraders was greater than that observed with several Pseudomonas 2,4-diacetylphloroglucinol-producing strains and with Pseudomonas chlororaphis PCL1391, which relies on production of phenazine antibiotic for disease suppression. Phenazine production by this well characterized biological control strain P. chlororaphis PCL1391 is regulated by AHL-mediated quorum sensing. When P. chlororaphis PCL1391 was co-inoculated with P. fluorescens P3/pME6863 in a strain mixture, the AHL degrader interfered with the normally excellent ability of the antibiotic producer to suppress tomato vascular wilt caused by Fusarium oxysporum f. sp. lycopersici. Our results demonstrate AHL degradation as a novel biocontrol mechanism, but also demonstrate the potential for non-target interactions that can interfere with the biocontrol efficacy of other strains. PMID:19719608

  16. New PCR Assays for the Identification of Fusarium verticillioides, Fusarium subglutinans, and Other Species of the Gibberella fujikuroi Complex

    PubMed Central

    Faria, Carla Bertechini; Abe, Camila Agnes Lumi; da Silva, Cleiltan Novais; Tessmann, Dauri José; Barbosa-Tessmann, Ione Parra

    2012-01-01

    Fusarium verticillioides and Fusarium subglutinans are important fungal pathogens of maize and other cereals worldwide. In this study, we developed PCR-based protocols for the identification of these pathogens targeting the gaoB gene, which codes for galactose oxidase. The designed primers recognized isolates of F. verticillioides and F. subglutinans that were obtained from maize seeds from several producing regions of Brazil but did not recognize other Fusarium spp. or other fungal genera that were either obtained from fungal collections or isolated from maize seeds. A multiplex PCR protocol was established to simultaneously detect the genomic DNA from F. verticillioides and F. subglutinans. This protocol could detect the DNA from these fungi growing in artificially or naturally infected maize seeds. Another multiplex reaction with a pair of primers developed in this work combined with a pre-existing pair of primers has allowed identifying F. subglutinans, F. konzum, and F. thapsinum. In addition, the identification of F. nygamai was also possible using a combination of two PCR reactions described in this work, and another described in the literature. PMID:22312242

  17. eFG: an electronic resource for Fusarium graminearum

    PubMed Central

    Liu, Xiaoping; Zhang, Xiaodong; Tang, Wei-Hua; Chen, Luonan; Zhao, Xing-Ming

    2013-01-01

    Fusarium graminearum is a plant pathogen, which causes crop diseases and further leads to huge economic damage worldwide in past decades. Recently, the accumulation of different types of molecular data provides insights into the pathogenic mechanism of F. graminearum, and might help develop efficient strategies to combat this destructive fungus. Unfortunately, most available molecular data related to F. graminearum are distributed in various media, where each single source only provides limited information on the complex biological systems of the fungus. In this work, we present a comprehensive database, namely eFG (Electronic resource for Fusarium graminearum), to the community for further understanding this destructive pathogen. In particular, a large amount of functional genomics data generated by our group is deposited in eFG, including protein subcellular localizations, protein–protein interactions and orthologous genes in other model organisms. This valuable knowledge can not only help to disclose the molecular underpinnings of pathogenesis of the destructive fungus F. graminearum but also help the community to develop efficient strategies to combat this pathogen. To our best knowledge, eFG is the most comprehensive functional genomics database for F. graminearum until now. The eFG database is freely accessible at http://csb.shu.edu.cn/efg/ with a user-friendly and interactive interface, and all data can be downloaded freely. Database URL: http://csb.shu.edu.cn/efg/ PMID:23798489

  18. Effects of the Fusarium verticillioides mycotoxin, fumonisin B1, on maize stomatal behavior

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides is a non-obligate plant pathogen causing a number of maize diseases and is responsible for the production of fumonisin B1 (FB1), a potential human carcinogen and agent of fatal farm animal diseases. The effect of FB1 on the health and development of maize seedlings was recen...

  19. Synteny in Toxigenic Fusarium Species: The Fumonisin Gene Cluster and the Mating Type Region as Examples

    Microsoft Academic Search

    Cees Waalwijk; Theo van der Lee; Ineke de Vries; Thamara Hesselink; Joop Arts; Gert H. J. Kema

    2004-01-01

    A comparative genomic approach was used to study the mating type locus and the gene cluster involved in toxin production (fumonisin) in Fusarium proliferatum, a pathogen with a wide host range and a complex toxin profile. A BAC library, generated from F. proliferatum isolate ITEM 2287, was used to identify chromosomal regions flanking the mating type locus and the gene

  20. CLM1 of Fusarium graminearum Encodes a Longiborneol Synthase Required for Culmorin Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium graminearum is a serious fungal pathogen of cereal crops (e.g. wheat, barley, maize) and produces a number of mycotoxins including 15-acetyldeoxynivalenol, butenolide, zearalenone, and culmorin. To identify a biosynthetic gene for the culmorin pathway, an EST database was examined for terp...

  1. On the reliability of Fusarium oxysporum f. sp. niveum research: Do we need standardized testing methods?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium oxysporum f. sp. nivium (Fon) is a pathogen highly variable in aggressiveness that requires a standardized testing method to more accurately define isolate aggressiveness (races) and to identify resistant watermelon lines. Isolates of Fon vary in aggressiveness from weakly to highly aggres...

  2. Regulation of secondary metabolite production in Fusarium species by the global regulator LAE1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium species are pathogens of corn and wheat and are capable of producing secondary metabolites that are a food safety concern. These mycotoxins include fumonins and trichothecenes which have known carcinogenic potential and can inhibit protein synthesis respectively in animals. In addition to t...

  3. Identification and analysis of Fusarium verticillioides genes differentially expressed during conidiation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides, an endophytic maize pathogen, is the causal agent of diseases such as ear rot, seedling blight, and stalk rot, resulting in major economic losses in maize production. This fungus can also cause certain diseases in animals due to consumption of feed contaminated with fumonis...

  4. Tricarballylic ester formation during biosynthesis of fumonisin mycotoxins in Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fumonisins are polyketide-derived mycotoxins produced by Fusarium verticillioides, a widespread fungal pathogen of corn, and a common contaminant of corn-based food and feeds. Fumonisins contain two tricarballylic esters that are rare structural features in natural products. Here, we expressed thr...

  5. Nitric oxide metabolism and the role of NO detoxifying flavohaemoglobin in Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nitric oxide (NO) is a small free radical, highly reactive, and responsible for both cytotoxic and cytostimulant effects in the cell. The dual nature of NO makes it the perfect candidate for both molecular signaling and an effective first line of defense against pathogens. Fusarium verticillioides i...

  6. Molecular characterization of the Cysteine2-Histidine2 transcription factor Ace1 in Fusarium verticillioides 

    E-print Network

    Campbell, Jacquelyn 1990-

    2012-04-27

    Fusarium verticillioides is a pathogen of corn that causes yield losses and food safety issues due to mycotoxin production. This research project focuses on a cysteine2- histidine2 transcription factor, named FvAce1, which is predicted to play a...

  7. Genetic Basis for the 3-ADON and 15-ADON Trichothecene Chemotypes in Fusarium graminearum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In some regions of the world, most strains of the wheat head blight pathogen Fusarium graminearum have one of two trichothecene mycotoxin production profiles (chemotypes), which are designated as 3-ADON and 15-ADON. In a defined medium, strains with the 3-ADON chemotype produce a trichothecene (3-a...

  8. VALIDATION OF DNA MICROARRAYS DERIVED FROM THE FUSARIUM VERTICILLIOIDES GENE INDEX

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides is a pathogen of maize and it can produce the toxic polyketide derived secondary metabolites called fumonisins. Fumonisins have been shown to cause animal diseases and are epidemiologically correlated to esophageal cancer and neural tube defects in humans. In an effort to ...

  9. Analysis of deoxynivalenol and deoxynivalenol-3-glucoside in hard red spring wheat inoculated with Fusarium graminearum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Deoxynivalenol (DON) is a mycotoxin which isproduced by plant pathogens such as Fusarium species. The formation of the "masked" mycotoxin deoxinyvalenol-3-glucoside (D3G) results from a defense mechanism the plant uses for detoxification. These two mycotoxins are important from the food safety poi...

  10. Development of a new MLST scheme for differentiation of Fusarium solani Species Complex (FSSC) isolates

    Microsoft Academic Search

    Anne Debourgogne; Cécile Gueidan; Christophe Hennequin; Nelly Contet-Audonneau; Sybren de Hoog; Marie Machouart

    2010-01-01

    Fungi belonging to the Fusarium solani Species Complex (FSSC) are well known plant pathogens. In addition to being the causative agent of some superficial infections, FSSC has recently emerged as a group of common opportunistic moulds, mainly in patients with haematological malignancies. Molecular typing methods are essential in order to better understand the epidemiology of such opportunistic agents with the

  11. Structural and Functional Characterization of TRI3 Acetyltransferase from Fusarium sporotrichioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium Head Blight (FHB) is a devastating disease of cereal crops whose worldwide incidence is increasing and at present there is no satisfactory way of combating this pathogen or its associated toxins. There is a wide variety of trichothecene mycotoxins and they all contain a 12,13-epoxytrichoth...

  12. Characterization and complementation of an apparent FUM gene cluster deletion in Fusarium verticillioides.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The filamentous ascomycete Fusarium verticillioides is a worldwide pathogen of maize and produces the fumonisin mycotoxins. Contamination of maize kernels with fumonisin B1 (FB1) is of significant concern because of its causal role in equine leukoencephalomalacia, porcine pulmonary edema, liver and...

  13. N-acetylcysteine inhibits germination of conidia and growth of Aspergillus spp. and Fusarium spp.

    PubMed Central

    De Lucca, A J; Walsh, T J; Daigle, D J

    1996-01-01

    N-Acetylcysteine inhibited hyphal growth and germination of conidia of Aspergillus spp. and Fusarium spp. N-Acetylcysteine inhibited conidial germination as well as or better than L-cysteine. Cysteine-related compounds may provide a potential therapeutic strategy against agriculturally and medically important fungal pathogens. PMID:8723482

  14. Trichothecene genotypes and chemotypes in Fusarium graminearum complex strains isolated from maize fields of northwest Argentina

    Microsoft Academic Search

    D. A. Sampietro; M. E. Aristimuño Ficoseco; C. M. Jimenez; M. A. Vattuone; C. A. Catalán

    Members of the Fusarium graminearum species complex (Fg complex) cause Gibberella ear rot in maize from northwest Argentina. The potential of these pathogens to contaminate maize grains with type B trichothecenes is a health risk for both humans and animals. We evaluated the reliability of multiplex PCR assays based on TRI3 and TRI12 genes, and single PCR assays based on

  15. QTL Mapping for Fusarium Ear Rot and Fumonisin Contamination Resistance in Two Maize Populations

    Microsoft Academic Search

    Leilani A. Robertson-Hoyt; Michael P. Jines; Peter J. Balint-Kurti; Craig E. Kleinschmidt; Don G. White; Gary A. Payne; Chris M. Maragos; Terence L. Molnár; James B. Holland

    2006-01-01

    Fusarium verticillioides (Sacc.) Nirenberg (synonym F. monili- forme Sheldon) (teleomorph: Gibberella moniliformis) and F. prolif- eratum (Matsushima) Nirenberg (teleomorph: G. intermedia) are fungal pathogens of maize (Zea mays L.) that cause ear rot and con- taminate grain with fumonisins, mycotoxins that can harm animals and humans. The objective of this study was to identify quantitative trait loci (QTL) for resistance

  16. Fusarium subglutinans: A new eumycetoma agent?

    PubMed Central

    Campos-Macías, Pablo; Arenas-Guzmán, Roberto; Hernández-Hernández, Francisca

    2013-01-01

    Eumycetoma is a chronic subcutaneous mycosis mainly caused by Madurella spp. Fusarium opportunistic infections in humans are often caused by Fusarium solani and Fusarium oxysporum. We report a case of eumycetoma by F. subglutinans, diagnosed by clinical aspect and culture, and confirmed by PCR sequencing. The patient was successfully treated with oral itraconazole. To our knowledge, this is the second report of human infection and the first case of mycetoma by Fusarium subglutinans. PMID:24432236

  17. Development of a novel multiplex DNA microarray for Fusarium graminearum and analysis of azole fungicide responses

    Microsoft Academic Search

    Rayko Becher; Fabian Weihmann; Holger B Deising; Stefan GR Wirsel

    2011-01-01

    BACKGROUND: The toxigenic fungal plant pathogen Fusarium graminearum compromises wheat production worldwide. Azole fungicides play a prominent role in controlling this pathogen. Sequencing of its genome stimulated the development of high-throughput technologies to study mechanisms of coping with fungicide stress and adaptation to fungicides at a previously unprecedented precision. DNA-microarrays have been used to analyze genome-wide gene expression patterns and

  18. Loss of function of the Fusarium oxysporum SNF1 gene reduces virulence on cabbage and Arabidopsis

    Microsoft Academic Search

    Manuel D. Ospina-Giraldo; Ewen Mullins; Seogchan Kang

    2003-01-01

    Fusarium oxysporum pathogenicity is believed to require the activity of cell wall-degrading enzymes. Production of these enzymes in fungi is subject to carbon catabolite repression, a process that in yeast is mostly controlled by the SNF1 (sucrose non-fermenting 1) gene. To elucidate the role of cell wall-degrading enzymes in F. oxysporum pathogenicity, we cloned and disrupted its SNF1 homologue ( FoSNF1).

  19. The In Planta Transcriptome of Ralstonia solanacearum: Conserved Physiological and Virulence Strategies during Bacterial Wilt of Tomato

    PubMed Central

    Jacobs, Jonathan M.; Babujee, Lavanya; Meng, Fanhong; Milling, Annett; Allen, Caitilyn

    2012-01-01

    ABSTRACT Plant xylem fluid is considered a nutrient-poor environment, but the bacterial wilt pathogen Ralstonia solanacearum is well adapted to it, growing to 108 to 109 CFU/g tomato stem. To better understand how R. solanacearum succeeds in this habitat, we analyzed the transcriptomes of two phylogenetically distinct R. solanacearum strains that both wilt tomato, strains UW551 (phylotype II) and GMI1000 (phylotype I). We profiled bacterial gene expression at ~6 × 108 CFU/ml in culture or in plant xylem during early tomato bacterial wilt pathogenesis. Despite phylogenetic differences, these two strains expressed their 3,477 common orthologous genes in generally similar patterns, with about 12% of their transcriptomes significantly altered in planta versus in rich medium. Several primary metabolic pathways were highly expressed during pathogenesis. These pathways included sucrose uptake and catabolism, and components of these pathways were encoded by genes in the scrABY cluster. A UW551 scrA mutant was significantly reduced in virulence on resistant and susceptible tomato as well as on potato and the epidemiologically important weed host Solanum dulcamara. Functional scrA contributed to pathogen competitive fitness during colonization of tomato xylem, which contained ~300 µM sucrose. scrA expression was induced by sucrose, but to a much greater degree by growth in planta. Unexpectedly, 45% of the genes directly regulated by HrpB, the transcriptional activator of the type 3 secretion system (T3SS), were upregulated in planta at high cell densities. This result modifies a regulatory model based on bacterial behavior in culture, where this key virulence factor is repressed at high cell densities. The active transcription of these genes in wilting plants suggests that T3SS has a biological role throughout the disease cycle. PMID:22807564

  20. A Genetic Mechanism for Emergence of Races in Fusarium oxysporum f. sp. lycopersici: Inactivation of Avirulence Gene AVR1 by Transposon Insertion

    PubMed Central

    Inami, Keigo; Yoshioka-Akiyama, Chizu; Morita, Yasuaki; Yamasaki, Mutsuko; Teraoka, Tohru; Arie, Tsutomu

    2012-01-01

    Compatible/incompatible interactions between the tomato wilt fungus Fusarium oxysporum f. sp. lycopersici (FOL) and tomato Solanum lycopersicum are controlled by three avirulence genes (AVR1–3) in FOL and the corresponding resistance genes (I–I3) in tomato. The three known races (1, 2 and 3) of FOL carry AVR genes in different combinations. The current model to explain the proposed order of mutations in AVR genes is: i) FOL race 2 emerged from race 1 by losing the AVR1 and thus avoiding host resistance mediated by I (the resistance gene corresponding to AVR1), and ii) race 3 emerged when race 2 sustained a point mutation in AVR2, allowing it to evade I2-mediated resistance of the host. Here, an alternative mechanism of mutation of AVR genes was determined by analyses of a race 3 isolate, KoChi-1, that we recovered from a Japanese tomato field in 2008. Although KoChi-1 is race 3, it has an AVR1 gene that is truncated by the transposon Hormin, which belongs to the hAT family. This provides evidence that mobile genetic elements may be one of the driving forces underlying race evolution. KoChi-1 transformants carrying a wild type AVR1 gene from race 1 lost pathogenicity to cultivars carrying I, showing that the truncated KoChi-1 avr1 is not functional. These results imply that KoChi-1 is a new race 3 biotype and propose an additional path for emergence of FOL races: Race 2 emerged from race 1 by transposon-insertion into AVR1, not by deletion of the AVR1 locus; then a point mutation in race 2 AVR2 resulted in emergence of race 3. PMID:22952887

  1. Production of fusarielins by Fusarium.

    PubMed

    Sørensen, Jens Laurids; Akk, Elina; Thrane, Ulf; Giese, Henriette; Sondergaard, Teis Esben

    2013-01-01

    Fusarielins constitute a relative unexplored group of secondary metabolites, which have been isolated mainly from unidentified Aspergillus and Fusarium strains. In the present study we show that the ability to produce fusarielins is restricted to a few Fusarium species. Among the 15 analyzed species fusarielins were identified only in extracts from Fusarium graminearum and Fusarium tricinctum. The influence of different carbon sources on fusarielin biosynthesis was examined and the results showed that disaccharides and dextrin in combination with arginine as sole nitrogen source increased fusarielin production. When arginine was replaced with nitrate the fusarielins were produced on a wider selection of carbon sources including all monosaccharides. Production of fusarielins in F. graminearum was also influenced by pH, cultivation time, temperature and fructose concentration with the optimal conditions being: pH6, 25°C, 26days and 60mg fructose/mL. Wheat spikes were inoculated with F. graminearum to determine whether fusarielins are produced in infected cereals and fusarielin H was detected in all samples ranging from 392 to 1865ng/g (mean: 989ng/g) indicating that fusarielins are produced during infection. The study shows that even though fusarielins are produced by a narrow list of Fusarium species, they potentially can be present in infected cereals. PMID:23290226

  2. Filamentous Fungi (Magnaporthe grisea and Fusarium oxysporum).

    PubMed

    Khang, Chang Hyun; Park, Sook-Young; Rho, Hee-Sool; Lee, Yong-Hwan; Kang, Seogchan

    2006-01-01

    A better understanding of fungal biology will facilitate judicious use of beneficial fungi and will also advance our efforts to control pathogenic fungi. Molecular studies of fungal biology have been greatly aided by transformation-mediated mutagenesis techniques. Transformation via nonhomologous integration of plasmid DNA bearing a selectable marker (e.g., antibiotic resistance gene) has been widely used for the random insertional mutagenesis of fungi - as an alternative to chemical and radiation mutagens - mainly because the integration of plasmid into the genome provides a convenient tag for subsequent identification and isolation of the mutated gene. Homologous recombination between a target gene on the chromosome and the introduced DNA carrying its mutant allele results in targeted gene knock-out. An important advance in fungal transformation methodology is the development of Agrobacterium tumefaciens-mediated transformation (ATMT) protocols for fungi. ATMT has been successfully applied to a phylogenetically diverse group of fungi and offers a number of advantages over conventional transformation techniques in both the random insertional mutagenesis and targeted gene knock-out. In this chapter, we describe ATMT protocols and vectors for fungal gene manipulation using two plant pathogenic fungi, Magnaporthe grisea and Fusarium oxysporum, as target organisms. PMID:17033082

  3. Variation in antibiosis ability, against potato pathogens, of bacterial communities recovered from the endo- and exoroots of potato crops produced under conventional versus minimum tillage systems.

    PubMed

    Sturz, A V; Peters, R D; Carter, M R; Sanderson, J B; Matheson, B G; Christie, B R

    2005-08-01

    The culturable component of bacterial communities found in the endoroot and associated exoroot (root zone soil) was examined in potatoes (Solanum tuberosum L.) grown under either conventional or minimum tillage systems. Bacterial species--abundance relationships were determined and in vitro antibiosis ability investigated to discover whether tillage practice or bacteria source (endo- or exoroot) influenced bacterial community structure and functional versatility. Antibiosis abilities against Phytophthora erythroseptica Pethyb. (causal agent of pink rot of potatoes), Streptomyces scabies (Thaxt.) Waksm. and Henrici) (causal agent of potato common scab), and Fusarium oxysporum Schlecht. Emend. Snyder and Hansen (causal agent of fusarium potato wilt) were selected as indicators of functional versatility. Bacterial community species richness and diversity indices were significantly greater (P = 0.001) in the exoroot than in the endoroot. While both endo- and exoroot communities possessed antibiosis ability against the phytopathogens tested, a significantly greater proportion (P = 0.0001) of the endoroot population demonstrated antibiosis ability than its exoroot counterpart against P. erythroseptica and F. oxysporum. Tillage regime had no significant influence on species-abundance relationships in the endo- or exoroot but did influence the relative antibiosis ability of bacteria in in vitro challenges against S. scabies, where bacteria sourced from minimum tillage systems were more likely to have antibiosis ability (P = 0.0151). We postulate that the difference in the frequency of isolates with antibiosis ability among endoroot versus exoroot populations points to the adaptation of endophytic bacterial communities that favour plant host defence against pathogens that attack the host systemically. PMID:16234863

  4. The role of mycelium production and a MAPK-mediated immune response in the C. elegans-Fusarium model system.

    PubMed

    Muhammed, Maged; Fuchs, Beth Burgwyn; Wu, Michael P; Breger, Julia; Coleman, Jeffrey J; Mylonakis, Eleftherios

    2012-07-01

    Fusariosis is an emerging infectious complication of immune deficiency, but models to study this infection are lacking. The use of the soil nematode Caenorhabditis elegans as a model host to study the pathogenesis of Fusarium spp. was investigated. We observed that Fusarium conidia consumed by C. elegans can cause a lethal infection and result in more than 90% killing of the host within 120 hours, and the nematode had a significantly longer survival when challenged with Fusarium proliferatum compared to other species. Interestingly, mycelium production appears to be a major contributor in nematode killing in this model system, and C. elegans mutant strains with the immune response genes, tir-1 (encoding a protein containing a TIR domain that functions upstream of PMK-1) and pmk-1 (the homolog of the mammalian p38 MAPK) lived significantly shorter when challenged with Fusarium compared to the wild type strain. Furthermore, we used the C. elegans model to assess the efficacy and toxicity of various compounds against Fusarium. We demonstrated that amphotericin B, voriconazole, mancozeb, and phenyl mercury acetate significantly prolonged the survival of Fusarium-infected C. elegans, although mancozeb was toxic at higher concentrations. In conclusion, we describe a new model system for the study of Fusarium pathogenesis and evolutionarily preserved host responses to this important fungal pathogen. PMID:22225407

  5. The role of mycelium production and a MAPK-mediated immune response in the C. elegans-Fusarium model system

    PubMed Central

    Muhammed, Maged; Fuchs, Beth Burgwyn; WU, Michael P.; Breger, Julia; Coleman, Jeffrey J.; Mylonakis, Eleftherios

    2013-01-01

    Fusariosis is an emerging infectious complication of immune deficiency, but models to study this infection are lacking. The use of the soil nematode Caenorhabditis elegans as a model host to study the pathogenesis of Fusarium spp. was investigated. We observed that Fusarium conidia consumed by C. elegans can cause a lethal infection and result in more than 90% killing of the host within 120 hours, and the nematode had a significantly longer survival when challenged with Fusarium proliferatum compared to other species. Interestingly, mycelium production appears to be a major contributor in nematode killing in this model system, and C. elegans mutant strains with the immune response genes, tir-1 (encoding a protein containing a TIR domain that functions upstream of PMK-1) and pmk-1 (the homolog of the mammalian p38 MAPK) lived significantly shorter when challenged with Fusarium compared to the wild type strain. Furthermore, we used the C. elegans model to assess the efficacy and toxicity of various compounds against Fusarium. We demonstrated that amphotericin B, voriconazole, mancozeb, and phenyl mercury acetate significantly prolonged the survival of Fusarium-infected C. elegans, although mancozeb was toxic at higher concentrations. In conclusion, we describe a new model system for the study of Fusarium pathogenesis and evolutionarily preserved host responses to this important fungal pathogen. PMID:22225407

  6. Identification of a Chitinase-modifying Protein from Fusarium verticillioides

    PubMed Central

    Naumann, Todd A.; Wicklow, Donald T.; Price, Neil P. J.

    2011-01-01

    Chitinase-modifying proteins (cmps) are proteases secreted by fungal pathogens that truncate the plant class IV chitinases ChitA and ChitB during maize ear rot. cmp activity has been characterized for Bipolaris zeicola and Stenocarpella maydis, but the identities of the proteases are not known. Here, we report that cmps are secreted by multiple species from the genus Fusarium, that cmp from Fusarium verticillioides (Fv-cmp) is a fungalysin metalloprotease, and that it cleaves within a sequence that is conserved in class IV chitinases. Protein extracts from Fusarium cultures were found to truncate ChitA and ChitB in vitro. Based on this activity, Fv-cmp was purified from F. verticillioides. N-terminal sequencing of truncated ChitA and MALDI-TOF-MS analysis of reaction products showed that Fv-cmp is an endoprotease that cleaves a peptide bond on the C-terminal side of the lectin domain. The N-terminal sequence of purified Fv-cmp was determined and compared with a set of predicted proteins, resulting in its identification as a zinc metalloprotease of the fungalysin family. Recombinant Fv-cmp also truncated ChitA, confirming its identity, but had reduced activity, suggesting that the recombinant protease did not mature efficiently from its propeptide-containing precursor. This is the first report of a fungalysin that targets a nonstructural host protein and the first to implicate this class of virulence-related proteases in plant disease. PMID:21878653

  7. Fusarium graminearum and Its Interactions with Cereal Heads: Studies in the Proteomics Era

    PubMed Central

    Yang, Fen; Jacobsen, Susanne; Jørgensen, Hans J. L.; Collinge, David B.; Svensson, Birte; Finnie, Christine

    2013-01-01

    The ascomycete fungal pathogen Fusarium graminearum (teleomorph stage: Gibberella zeae) is the causal agent of Fusarium head blight in wheat and barley. This disease leads to significant losses of crop yield, and especially quality through the contamination by diverse fungal mycotoxins, which constitute a significant threat to the health of humans and animals. In recent years, high-throughput proteomics, aiming at identifying a broad spectrum of proteins with a potential role in the pathogenicity and host resistance, has become a very useful tool in plant-fungus interaction research. In this review, we describe the progress in proteomics applications toward a better understanding of F. graminearum pathogenesis, virulence, and host defense mechanisms. The contribution of proteomics to the development of crop protection strategies against this pathogen is also discussed briefly. PMID:23450732

  8. On the trail of a cereal killer: recent advances in Fusarium graminearum pathogenomics and host resistance.

    PubMed

    Kazan, Kemal; Gardiner, Donald M; Manners, John M

    2012-05-01

    The ascomycete fungal pathogen Fusarium graminearum (sexual stage: Gibberella zeae) causes the devastating head blight or scab disease on wheat and barley, and cob or ear rot disease on maize. Fusarium graminearum infection causes significant crop and quality losses. In addition to roles as virulence factors during pathogenesis, trichothecene mycotoxins (e.g. deoxynivalenol) produced by this pathogen constitute a significant threat to human and animal health if consumed in respective food or feed products. In the last few years, significant progress has been made towards a better understanding of the processes involved in F. graminearum pathogenesis, toxin biosynthesis and host resistance mechanisms through the use of high-throughput genomic and phenomic technologies. In this article, we briefly review these new advances and also discuss how future research can contribute to the development of sustainable plant protection strategies against this important plant pathogen. PMID:22098555

  9. Structural dynamics of Fusarium genomes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fungi in the genus Fusarium have a great negative impact on the world economy, yet also hold great potential for answering many fundamental biological questions. The advance of sequencing technologies has made possible the connection between phenotypes and genetic mechanisms underlying the acquisiti...

  10. Fusarium Keratitis - Multiple States, 2006

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The United States Centers for Disease Control and Prevention investigated an outbreak of corneal infections caused by Fusarium involving at least 17 states as of April, 2006. Initial outbreak reports were from Singapore and Hong Kong. Preliminary results suggest that these outbreaks may be linked ...

  11. Fatal disseminated fusarium infection in acute lymphoblastic leukaemia in complete remission

    PubMed Central

    Austen, B; McCarthy, H; Wilkins, B; Smith, A; Duncombe, A

    2001-01-01

    Fusarium species are increasingly recognised as serious pathogens in the immunocompromised. The outcome in the context of persistent severe neutropenia has been almost universally fatal. However, there have been several case reports of successful treatment if neutrophil recovery can be achieved. This report presents the case of a fatality that occurred despite neutrophil recovery. A 67 year old man developed disseminated fusariosis during the neutropenic phase of induction chemotherapy for acute lymphoblastic leukaemia. Fusarium dimerum was isolated from blood cultures. This species is highly unusual and very few case reports exist in the literature. An initial response to amphotericin treatment coincided with neutrophil recovery but a subsequent relapse occurred, despite adequate neutrophil counts, which proved fatal. It is postulated that reseeding of the blood from an occult site, namely the right vitreum in this case, led to this secondary relapse despite achieving complete leukaemic remission. Key Words: fusarium • disseminated • neutropenia • remission PMID:11376027

  12. The FUS3\\/KSS1Type MAP KinaseGene FPK1 Is Involved in Hyphal Growth, Conidiation and Plant Infection of Fusarium proliferatum

    Microsoft Academic Search

    Pei-Bao Zhao; Ai-Zhi Ren; Duo-Chuan Li

    2011-01-01

    Fusarium proliferatum is an important pathogen of maize that is responsible for ear rots, stalk rots and seeding blight worldwide. During the past decade, F. proliferatum has caused several severe epidemics of maize seedling blight in many areas of China, which led to significant losses in maize. To understand the molecular mechanisms in the fungal developmental regulation and pathogenicity, we

  13. The in planta transcriptome of Ralstonia solanacearum: conserved physiological and virulence strategies during bacterial wilt of tomato.

    PubMed

    Jacobs, Jonathan M; Babujee, Lavanya; Meng, Fanhong; Milling, Annett; Allen, Caitilyn

    2012-01-01

    Plant xylem fluid is considered a nutrient-poor environment, but the bacterial wilt pathogen Ralstonia solanacearum is well adapted to it, growing to 10(8) to 10(9) CFU/g tomato stem. To better understand how R. solanacearum succeeds in this habitat, we analyzed the transcriptomes of two phylogenetically distinct R. solanacearum strains that both wilt tomato, strains UW551 (phylotype II) and GMI1000 (phylotype I). We profiled bacterial gene expression at ~6 × 10(8) CFU/ml in culture or in plant xylem during early tomato bacterial wilt pathogenesis. Despite phylogenetic differences, these two strains expressed their 3,477 common orthologous genes in generally similar patterns, with about 12% of their transcriptomes significantly altered in planta versus in rich medium. Several primary metabolic pathways were highly expressed during pathogenesis. These pathways included sucrose uptake and catabolism, and components of these pathways were encoded by genes in the scrABY cluster. A UW551 scrA mutant was significantly reduced in virulence on resistant and susceptible tomato as well as on potato and the epidemiologically important weed host Solanum dulcamara. Functional scrA contributed to pathogen competitive fitness during colonization of tomato xylem, which contained ~300 µM sucrose. scrA expression was induced by sucrose, but to a much greater degree by growth in planta. Unexpectedly, 45% of the genes directly regulated by HrpB, the transcriptional activator of the type 3 secretion system (T3SS), were upregulated in planta at high cell densities. This result modifies a regulatory model based on bacterial behavior in culture, where this key virulence factor is repressed at high cell densities. The active transcription of these genes in wilting plants suggests that T3SS has a biological role throughout the disease cycle. IMPORTANCE Ralstonia solanacearum is a widespread plant pathogen that causes bacterial wilt disease. It inflicts serious crop losses on tropical farmers, with major economic and human consequences. It is also a model for the many destructive microbes that colonize the water-conducting plant xylem tissue, which is low in nutrients and oxygen. We extracted bacteria from infected tomato plants and globally identified the biological functions that R. solanacearum expresses during plant pathogenesis. This revealed the unexpected presence of sucrose in tomato xylem fluid and the pathogen's dependence on host sucrose for virulence on tomato, potato, and the common weed bittersweet nightshade. Further, R. solanacearum was highly responsive to the plant environment, expressing several metabolic and virulence functions quite differently in the plant than in pure culture. These results reinforce the utility of studying pathogens in interaction with hosts and suggest that selecting for reduced sucrose levels could generate wilt-resistant crops. PMID:22807564

  14. TPCP: Fusarium circinatum in pine nurseries FUSARIUM CIRCINATUM IN PINE NURSERIES

    E-print Network

    TPCP: Fusarium circinatum in pine nurseries FUSARIUM CIRCINATUM IN PINE NURSERIES: A GUIDE TO APPROPRIATE MANAGEMENT STRATEGIES Pine seedling infected with F. circinatum INTRODUCTION A number of Fusarium spp. have been found to cause diseases of pine seedlings and cuttings in South African nurseries. F

  15. Aggressiveness of Fusarium species and impact of root infection on growth and yield of soybeans.

    PubMed

    Arias, María M Díaz; Leandro, Leonor F; Munkvold, Gary P

    2013-08-01

    Fusarium spp. are commonly isolated from soybean roots but the pathogenic activity of most species is poorly documented. Aggressiveness and yield impact of nine species of Fusarium were determined on soybean in greenhouse (50 isolates) and field microplot (19 isolates) experiments. Root rot severity and shoot and root dry weights were compared at growth stages V3 or R1. Root systems were scanned and digital image analysis was conducted; yield was measured in microplots. Disease severity and root morphology impacts varied among and within species. Fusarium graminearum was highly aggressive (root rot severity >90%), followed by F. proliferatum and F. virguliforme. Significant variation in damping-off (20 to 75%) and root rot severity (<20 to >60%) was observed among F. oxysporum isolates. In artificially-infested microplots, root rot severity was low (<25%) and mean yield was not significantly reduced. However, there were significant linear relationships between yield and root symptoms for some isolates. Root morphological characteristics were more consistent indicators of yield loss than root rot severity. This study provides the first characterization of aggressiveness and yield impact of Fusarium root rot species on soybean at different plant stages and introduces root image analysis to assess the impact of root pathogens on soybean. PMID:23514263

  16. The Impact of Fusarium Mycotoxins on Human and Animal Host Susceptibility to Infectious Diseases

    PubMed Central

    Antonissen, Gunther; Martel, An; Pasmans, Frank; Ducatelle, Richard; Verbrugghe, Elin; Vandenbroucke, Virginie; Li, Shaoji; Haesebrouck, Freddy; Van Immerseel, Filip; Croubels, Siska

    2014-01-01

    Contamination of food and feed with mycotoxins is a worldwide problem. At present, acute mycotoxicosis caused by high doses is rare in humans and animals. Ingestion of low to moderate amounts of Fusarium mycotoxins is common and generally does not result in obvious intoxication. However, these low amounts may impair intestinal health, immune function and/or pathogen fitness, resulting in altered host pathogen interactions and thus a different outcome of infection. This review summarizes the current state of knowledge about the impact of Fusarium mycotoxin exposure on human and animal host susceptibility to infectious diseases. On the one hand, exposure to deoxynivalenol and other Fusarium mycotoxins generally exacerbates infections with parasites, bacteria and viruses across a wide range of animal host species. Well-known examples include coccidiosis in poultry, salmonellosis in pigs and mice, colibacillosis in pigs, necrotic enteritis in poultry, enteric septicemia of catfish, swine respiratory disease, aspergillosis in poultry and rabbits, reovirus infection in mice and Porcine Reproductive and Respiratory Syndrome Virus infection in pigs. However, on the other hand, T-2 toxin has been shown to markedly decrease the colonization capacity of Salmonella in the pig intestine. Although the impact of the exposure of humans to Fusarium toxins on infectious diseases is less well known, extrapolation from animal models suggests possible exacerbation of, for instance, colibacillosis and salmonellosis in humans, as well. PMID:24476707

  17. Relationship between Cell Wall Susceptibility to Cellulases and Pectinases of Fusarium oxysporum and Susceptibility of Date Palm Cultivars

    Microsoft Academic Search

    C. El Modafar; E. El Boustani

    2000-01-01

    Fusarium oxysporum f. sp. albedinis, the bayoud disease agent of date palm, grows on a mineral medium containing the cell walls of date palm roots as a sole carbohydrate source. The growth and development of pathogen under these conditions was related to the production of extracellular cell wall-degrading enzymes (CWDE): cellulases, polygalacturonases, polygalacturonate transeliminases, and pectinmethylesterases. The mycelial growth and

  18. Relationship of substrate and surfactin production by Bacillus mojavensis strains and their antagonistical response to Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The endophytic bacterium, Bacillus mojavensis, RRC 101 controls fungal diseases in maize and other plants. The bacterium and its cultural extracts have been shown to be antagonistic to the pathogenic and mycotoxic fungus, Fusarium verticillioides. An antifungal lipopeptide produced by B. mojavensi...

  19. The role of MeaB, NMR and AreB as antagonists of AreA in Fusarium fujikuroi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The rice pathogen Fusarium fujikuroi produces the phytohormones gibberellins (GAs), and the red polyketide pigment bikaverin. The production of both metabolites is subject to nitrogen metabolite repression (NMR): the central regulator of nitrogen repression, AreA, has been shown to directly activa...

  20. IdentiWcation of a gene cluster responsible for the biosynthesis of aurofusarin in the Fusarium graminearum species complex

    Microsoft Academic Search

    Sascha Malz; Morten N. Grell; Charlotte Thrane; Frank J. Maier; Pernille Rosager; Angelika Felk; Klaus S. Albertsen; Siegfried Salomon; Lisbeth Bohn; Wilhelm Schäfer; Henriette Giese

    The red pigmentation of Fusarium graminearum and related species that cause stem and head blight of cereals is due to the depo- sition of aurofusarin in the cell walls. To determine the importance of this polyketide for fungal physiology and pathogenicity, auro- fusarin deWcient mutants were produced by random and targeted mutagenesis of F. pseudograminearum and F. graminearum. We show

  1. Genotype Response of Soybean (Glycine max) Whole Plants and Hairy Roots to Fusarium solani f. sp. glycines Infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium solani f. sp. Glycines, a soilborne fungus, infects soybean roots and causes sudden death syndrome. The response of 13 soybean genotypes to the pathogen infection was tested with potted greenhouse grown plants and with cultured hairy roots. The taproots of all genotypes grown plants measure...

  2. FUMONISIN PRODUCTION AND BIOAVAILABILITY TO MAIZE SEEDLINGS GROWN FROM SEEDS INOCULATED WITH FUSARIUM VERTICILLIOIDES AND GROWN IN NATURAL SOILS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fungus Fusarium verticillioides infects maize and produces fumonisins. The purpose of this study was to determine the ability of F. verticillioides to produce fumonisins in synthetic and natural soils and their biological availability to maize roots. Maize seeds were inoculated with a pathogen...

  3. Reduced susceptibility to Fusarium head blight in Brachypodium distachyon through priming with the Fusarium mycotoxin deoxynivalenol.

    PubMed

    Blümke, Antje; Sode, Björn; Ellinger, Dorothea; Voigt, Christian A

    2015-06-01

    The fungal cereal pathogen Fusarium graminearum produces deoxynivalenol (DON) during infection. The mycotoxin DON is associated with Fusarium head blight (FHB), a disease that can cause vast grain losses. Whilst investigating the suitability of Brachypodium distachyon as a model for spreading resistance to F.?graminearum, we unexpectedly discovered that DON pretreatment of spikelets could reduce susceptibility to FHB in this model grass. We started to analyse the cell wall changes in spikelets after infection with F.?graminearum wild-type and defined mutants: the DON-deficient ?tri5 mutant and the DON-producing lipase disruption mutant ?fgl1, both infecting only directly inoculated florets, and the mitogen-activated protein (MAP) kinase disruption mutant ?gpmk1, with strongly decreased virulence but intact DON production. At 14 days post-inoculation, the glucose amounts in the non-cellulosic cell wall fraction were only increased in spikelets infected with the DON-producing strains wild-type, ?fgl1 and ?gpmk1. Hence, we tested for DON-induced cell wall changes in B.?distachyon, which were most prominent at DON concentrations ranging from 1 to 100?ppb. To test the involvement of DON in defence priming, we pretreated spikelets with DON at a concentration of 1?ppm prior to F.?graminearum wild-type infection, which significantly reduced FHB disease symptoms. The analysis of cell wall composition and plant defence-related gene expression after DON pretreatment and fungal infection suggested that DON-induced priming of the spikelet tissue contributed to the reduced susceptibility to FHB. PMID:25202860

  4. A comparison of Cephalosporium isolates that cause hardwood wilts 

    E-print Network

    Bush, David Lynn

    1973-01-01

    (~bios ros vair in(ann) in Tennessee (5). Tersissoon silt was soon found in Mississippi, Alabama, North Carolina, South Carolina, Georgia, Florida, and Texas. Persimmon wilt has almost eradicated American persimmons in Central Tennessee (23... and South America, was susceptible to persimmon wilt. Dio- ~sos dis olo R'ld. , fran the phllippi e; ~Dos ro rosei. st dier, f oe Me ito; a d D~o tan R h. , ~sos 1 t L. d ~pfos ros kaki L. , i trod ted fr Japan and China, proved to be highly resistant...

  5. A novel, sensitive method to evaluate potato germplasm for bacterial wilt resistance using a luminescent Ralstonia solanacearum reporter strain.

    PubMed

    Cruz, Andrea Paola Zuluaga; Ferreira, Virginia; Pianzzola, María Julia; Siri, María Inés; Coll, Núria S; Valls, Marc

    2014-03-01

    Several breeding programs are under way to introduce resistance to bacterial wilt caused by Ralstonia solanacearum in solanaceous crops. The lack of screening methods allowing easy measurement of pathogen colonization and the inability to detect latent (i.e., symptomless) infections are major limitations when evaluating resistance to this disease in plant germplasm. We describe a new method to study the interaction between R. solanacearum and potato germplasm that overcomes these restrictions. The R. solanacearum UY031 was genetically modified to constitutively generate light from a synthetic luxCDABE operon stably inserted in its chromosome. Colonization of this reporter strain on different potato accessions was followed using life imaging. Bacterial detection in planta by this nondisruptive system correlated with the development of wilting symptoms. In addition, we demonstrated that quantitative detection of the recombinant strain using a luminometer can identify latent infections on symptomless potato plants. We have developed a novel, unsophisticated, and accurate method for high-throughput evaluation of pathogen colonization in plant populations. We applied this method to compare the behavior of potato accessions with contrasting resistance to R. solanacearum. This new system will be especially useful to detect latency in symptomless parental lines before their inclusion in long-term breeding programs for disease resistance. PMID:24283938

  6. Hyphal Growth of Phagocytosed Fusarium oxysporum Causes Cell Lysis and Death of Murine Macrophages

    PubMed Central

    Schäfer, Katja; Bain, Judith M.

    2014-01-01

    Fusarium oxysporum is an important plant pathogen and an opportunistic pathogen of humans. Here we investigated phagocytosis of F. oxysporum by J774.1 murine cell line macrophages using live cell video microscopy. Macrophages avidly migrated towards F. oxysporum germlings and were rapidly engulfed after cell-cell contact was established. F. oxysporum germlings continued hyphal growth after engulfment by macrophages, leading to associated macrophage lysis and escape. Macrophage killing depended on the multiplicity of infection. After engulfment, F. oxysporum inhibited macrophages from completing mitosis, resulting in large daughter cells fused together by means of a F. oxysporum hypha. These results shed new light on the initial stages of Fusarium infection and the innate immune response of the mammalian host. PMID:25025395

  7. Developing Fusarium head blight resistant wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight, caused by Fusarium graminearum, is a major disease problem in wheat and barley around the world. During infection, F. graminearum produces trichothecene mycotoxins that act as virulence factors and cause a reduction in grain quality. Therefore, developing approaches to detoxi...

  8. Biological and Chemical Complexity of Fusarium proliferatum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The heterothallic ascomycete Fusarium proliferatum (teleomorph Gibberella intermedia) is a genetically diverse biological and phylogenetic species with a worldwide distribution and an unusually broad host range. F. proliferatum is a frequent component of the Fusarium ear rot complexes of maize and ...

  9. Epidemiology of Fusarium Diseases and their Mycotoxins in Maize Ears

    Microsoft Academic Search

    Gary P. Munkvold

    2003-01-01

    Fusarium species cause two distinct diseases on ears of maize, Fusarium ear rot (or pink ear rot) and Gibberella ear rot (or red ear rot), both of which can result in mycotoxin contamination of maize grain. The primary causal agent for Fusarium ear rot is Fusarium verticillioides, but F. subglutinans and F. proliferatum are also important. Gibberella ear rot is

  10. Antifungal activity of essential oils from basil (Ocimum basilicum Linn.) and sweet fennel (Ocimum gratissimum Linn.): Alternative strategies to control pathogenic fungi in organic rice

    Microsoft Academic Search

    Apinya Piyo; Pitipong Thobunluepop

    This in vitro study was aimed to evaluate the mycelium growth and spore germination inhibition properties of Thai medicinal essential oils. The oil from two species of Thai medicinal plant; Basil (Ocimum basilicum Linn) and Sweet Fennel (Ocimum gratissimum linn.), were applied against 7 species of rice pathogenic fungi; Alternaria brassicicola, Aspergillus flavus, Bipolaris oryzae, Fusarium moniliforme, Fusarium proliferatum, Pyricularia

  11. Fusarium proliferatum as an agent of disseminated infection in an immunosuppressed patient.

    PubMed Central

    Summerbell, R C; Richardson, S E; Kane, J

    1988-01-01

    Fusarium proliferatum was reported as the agent of a fatal disseminated infection in a child with lymphoblastic leukemia. The fungus has not been reported previously to cause disease in humans, but it is closely related to the known opportunistic pathogen F. verticillioides. It was distinguished by the production of clavate microconidia in chains from proliferating phialides. Resistance to amphotericin B and flucytosine in vitro was shown. Images PMID:3422646

  12. Isoflavonoid accumulation in soybean hairy roots upon treatment with Fusarium solani

    Microsoft Academic Search

    Vera V. Lozovaya; Anatoliy V. Lygin; Olga V. Zernova; Shuxian Li; Glen L. Hartman; Jack M. Widholm

    2004-01-01

    Hairy roots were initiated from two soybean [Glycine max (L.) Merr.] genotypes with different susceptibility (susceptible ‘Spencer’ and partially resistant ‘PI567.374’) to the disease sudden death syndrome (SDS) caused by the soil-borne fungal pathogen Fusarium solani f. sp. glycines (FSG) to study the role of isoflavonoids in the plant response to FSG infection. Hairy root cultures obtained by transformation with

  13. Morphological and molecular characterization of Fusarium verticillioides from rotten banana imported into Japan

    Microsoft Academic Search

    Takashi Hirata; Etsuo Kimishima; Takayuki Aoki; Helgard I. Nirenberg; Kerry O'Donnell

    2001-01-01

    Seven strains ofFusarium were isolated from rotten fruit of banana (Musa cavendishii) imported into Japan from Mazanillo, Colima, Mexico. Morphological features of the isolates were described and illustrated,\\u000a and their pathogenicity to banana was determined. Morphological and molecular phylogenetic analyses revealed that these isolates\\u000a were assignable toF. verticillioides. However, constant production of septate aerial conidia in chains by the banana

  14. Pantothenate synthetase from Fusarium oxysporum f. sp . lycopersici is induced by a-tomatine

    Microsoft Academic Search

    A. Pérez-Espinosa; T. Roldán-Arjona; M. Ruiz-Rubio

    2001-01-01

    The steroidal glycoalkaloid !-tomatine which is present in tomato (Lycopersicum sculentum) is assumed to protect the plant against phytopathogenic fungi. We have isolated a gene from the fungal pathogen Fusarium oxysporum f. sp. lycopersici that is induced by this glycoalkaloid. This gene, designated panC, encodes a predicted protein with a molecular mass of 41 kDa that shows a high degree

  15. Evidence for an expanded host range of Fusarium oxysporum f.sp. raphani

    Microsoft Academic Search

    Angelo Garibaldi; Giovanna Gilardi; Maria Lodovica Gullino

    2006-01-01

    The pathogenicity of four isolates ofFusarium oxysporum obtained from infected cultivated rocket (Eruca vesicaria) and wild (sand) rocket (Diplotaxis tenuifolia) was tested on the following cruciferous hosts: stock, radish, wild and cultivated rockets, and various species in the cabbage\\u000a tribe: cabbage (Brassica oleracea var.sabauda), cauliflower (Brassica oleracea var.botrytis), Brussels sprouts (Brassica oleracea var.gemmifera), broccoli (Brassica oleracea var.italica), turnip (Brassica rapa

  16. Arabidopsis dual resistance proteins, both RPS4 and RRS1, are required for resistance to bacterial wilt in transgenic Brassica crops.

    PubMed

    Narusaka, Mari; Hatakeyama, Katsunori; Shirasu, Ken; Narusaka, Yoshihiro

    2014-05-15

    Bacterial wilt phytopathogen Ralstonia solanacearum is a serious soil-borne disease that attacks several economically important plants worldwide, including Brassicaceae. Previous studies indicate that recognition of avirulence (Avr)-effector PopP2 by resistance (R) protein, RRS1-R, and physical interaction between RRS1-R and PopP2 in the nucleus are required for resistance. Of late, we showed that a pair of Arabidopsis thaliana TIR-NLR proteins, RRS1 and RPS4, function together in disease resistance against multiple pathogen isolates. Here, we report that dual R proteins, RRS1 and RPS4, from A. thaliana ecotype Wassilewskija confer resistance to bacterial wilt in transgenic Brassica crops. For practical applications, this finding may provide a new strategy for developing disease resistant plants that express R genes from other plants. PMID:24832367

  17. MOLECULAR SYSTEMATICS OF FUNGAL PLANT PATHOGENS: GENERALISATIONS FROM FUSARIUM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This presentation will focus on the importance of developing a robust phylogenetic framework for investigating species limits, evolution of virulence-associated factors such as toxins, host range, biogeography and global movement of agronomically important phytopathogens, drawing from examples of Fu...

  18. RNA silencing is required for Arabidopsis defence against Verticillium wilt disease

    PubMed Central

    Ellendorff, Ursula; Fradin, Emilie F.; de Jonge, Ronnie; Thomma, Bart P. H. J.

    2009-01-01

    RNA silencing is a conserved mechanism in eukaryotes that plays an important role in various biological processes including regulation of gene expression. RNA silencing also plays a role in genome stability and protects plants against invading nucleic acids such as transgenes and viruses. Recently, RNA silencing has been found to play a role in defence against bacterial plant pathogens in Arabidopsis through modulating host defence responses. In this study, it is shown that gene silencing plays a role in plant defence against multicellular microbial pathogens; vascular fungi belonging to the Verticillium genus. Several components of RNA silencing pathways were tested, of which many were found to affect Verticillium defence. Remarkably, no altered defence towards other fungal pathogens that include Alternaria brassicicola, Botrytis cinerea, and Plectosphaerella cucumerina, but also the vascular pathogen Fusarium oxysporum, was recorded. Since the observed differences in Verticillium susceptibility cannot be explained by notable differences in root architecture, it is speculated that the gene silencing mechanisms affect regulation of Verticillium-specific defence responses. PMID:19098131

  19. Genomic Insights into the Origin of Parasitism in the Emerging Plant Pathogen Bursaphelenchus xylophilus

    Microsoft Academic Search

    Taisei Kikuchi; James A. Cotton; Jonathan J. Dalzell; Koichi Hasegawa; Natsumi Kanzaki; Paul McVeigh; Takuma Takanashi; Isheng J. Tsai; Samuel A. Assefa; Peter J. A. Cock; Thomas Dan Otto; Martin Hunt; Adam J. Reid; Alejandro Sanchez-Flores; Kazuko Tsuchihara; Toshiro Yokoi; Mattias C. Larsson; Johji Miwa; Aaron G. Maule; Norio Sahashi; John T. Jones; Matthew Berriman

    2011-01-01

    Bursaphelenchus xylophilus is the nematode responsible for a devastating epidemic of pine wilt disease in Asia and Europe, and represents a recent, independent origin of plant parasitism in nematodes, ecologically and taxonomically distinct from other nematodes for which genomic data is available. As well as being an important pathogen, the B. xylophilus genome thus provides a unique opportunity to study

  20. Sequencing of K60, Type Strain of the Major Plant Pathogen Ralstonia solanacearum

    PubMed Central

    Remenant, Benoît; Babujee, Lavanya; Lajus, Aurélie; Médigue, Claudine; Prior, Philippe

    2012-01-01

    Ralstonia solanacearum is a widespread and destructive plant pathogen. We present the genome of the type strain, K60 (phylotype IIA, sequevar 7). Sequevar 7 strains cause ongoing tomato bacterial wilt outbreaks in the southeastern United States. K60 generally resembles R. solanacearum CFBP2957, a Caribbean tomato isolate, but has almost 360 unique genes. PMID:22535929

  1. Verticillium Wilt Resistance in U.S. Potato Breeding Programs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Verticillium wilt (VW), caused mainly by the soil-borne fungus V. dahliae, is a persistent and serious problem in potato production. Host-plant resistance offers an attractive control strategy, but major cultivars are susceptible to VW. Resistance to VW was evaluated in 14 advanced clones from U.S...

  2. Pine Wilt Disease And The Pinewood Nematode, Bursaphelenchus Xylophilus

    Microsoft Academic Search

    Manuel M. Mota; Kazuyoshi Futai; Paulo Vieira

    Pine wilt disease (PWD) is one of the most damaging events affecting conifer forests (in particular Pinus spp.), in the Far East (Japan, China and Korea), North America (USA and Canada) and, more recently, in the European Union\\u000a (Portugal). In Japan it became catastrophic, damaging native pine species (Pinus thunbergii and P. densiflora), and becoming the main forest problem, forcing

  3. Laurel wilt: A global threat to avocado production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Laurel wilt kills members of the Lauraceae plant family, including avocado. The disease has invaded much of the southeastern USA, and threatens avocado commerce and homeowner production in Florida, valuable germplasm in Miami (USDA-ARS), and major production and germplasm in California and MesoAmer...

  4. Verticillium wilts and management with special emphasis on lettuce.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Verticillium wilt causes billions of dollars in annual losses worldwide. The genus Verticillium contains several phytopathogenic species, the most important being V. dahliae, V. albo-atrum, and V. longisporum. The soilborne habitat of these species, and their capacity to infect a variety of crops, m...

  5. Expression of Baculovirus Anti-Apoptotic Genes p35 and op-iap in Cotton (Gossypium hirsutum L.) Enhances Tolerance to Verticillium Wilt

    PubMed Central

    Liang, Benguo; Li, Shanwei; Wu, Zhixia; Wang, Qianhua; Leng, Chunxu; Dong, Jiangli; Wang, Tao

    2010-01-01

    Background Programmed cell death plays an important role in mediating plant adaptive responses to the environment such as the invasion of pathogens. Verticillium wilt, caused by the necrotrophic pathogen Verticillium dahliae, is a serious vascular disease responsible for great economic losses to cotton, but the molecular mechanisms of verticillium disease and effective, safe methods of resistance to verticillium wilt remain unexplored. Methodology/Principal Findings In this study, we introduced baculovirus apoptosis inhibitor genes p35 and op-iap into the genome of cotton via Agrobacterium-mediated transformation and analyzed the response of transgenic plants to verticillium wilt. Results showed that p35 and op-iap constructs were stably integrated into the cotton genome, expressed in the transgenic lines, and inherited through the T3 generation. The transgenic lines had significantly increased tolerance to verticillium wilt throughout the developmental stages. The disease index of T1–T3 generation was lower than 19, significantly (P<0.05) better than the negative control line z99668. After treatment with 250 mg/L VD-toxins for 36 hours, DNA from negative control leaves was fragmented, whereas fragmentation in the transgenic leaf DNA did not occur. The percentage of cell death in transgenic lines increased by 7.11% after 60 mg/L VD-toxin treatment, which was less than that of the negative control lines's 21.27%. This indicates that p35 and op-iap gene expression partially protects cells from VD-toxin induced programmed cell death (PCD). Conclusion/Significance Verticillium dahliae can trigger plant cells to die through induction of a PCD mechanism involved in pathogenesis. This paper provides a potential strategy for engineering broad-spectrum necrotrophic disease resistance in plants. PMID:21151969

  6. Genomic Cross Comparison of Soybean Pathogens and the Symbiont Bradyrhizobium japonicum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plants are under constant attack from a variety of pathogens and respond with dramatic changes in gene expression. Some well-studied diseases of soybean include those induced by the pathogens Pseudomonas syringae, Fusarium virguliforme, and Sclerotinia sclerotiorum. To assist in the identification ...

  7. [Molecular identification and sequence analysis of broad bean wilt virus 2 isolates from atractylodes macrocephala Koidz].

    PubMed

    Niu, Yanbing; Shi, Xiaoli; Zhang, Ximei; Zhao, Huiqi; Zhao, Baojia

    2015-01-01

    To identity the pathogen that causes the mosaic and yellowing symptoms on Atractylodes macrocephala Koidz in Jiangxian, Shanxi province, biological inoculation, sequence-independent amplification (SIA),RT-PCR and other identification methods were used. The results showed that the chlorotic and necrosis symptoms occurred in the indicator plant Chenopodium quinoa after it was infected with the pathogen,and the same symptoms appeared after the reinoculation of healthy Atractylodes macrocephala Koidz; this reflected that the disease was likely to be caused by a virus. The results of SIA and sequencing showed that Broad bean wilt virus 2 (BBWV2) was present in severely mosaic Atractylodes macrocephala Koidz leaves. To further characterize the BBWV2 isolate from Atractylodes macrocephala (BBWV2-Am), the polyprotein partial gene encoded by BBWV2-Am RNA2 was cloned and sequenced. Sequence alignments showed that the nucleotide sequence identity of BBWV2-Am SCP and LCP genes ranged from 79.3% to 87.2% and from 80.1% to 89.2% compared to other BBWV2 strains,respectively; the deduced amino acid sequence similarities of the two gene products ranged from 91.2% to 95.7% and from 89.44 to 95.5%, respectively,compared to those of other BBWV2 strains. Phylogenetic comparisons showed that BBWV2-Am was most likely to be related to BBWV2-Rg,but formed an independent branch. This is the first report of BBWV2 in Atractylodes macrocephala Koidz. PMID:25997332

  8. Biogeography of Fusarium graminearum species complex and chemotypes: a review.

    PubMed

    van der Lee, Theo; Zhang, Hao; van Diepeningen, Anne; Waalwijk, Cees

    2015-01-01

    Differences in the geographic distribution of distinct trichothecene mycotoxins in wheat and barley were first recorded two decades ago. The different toxicological properties of deoxynivalenol (DON), nivalenol (NIV) and their acetylated derivatives require careful monitoring of the dynamics of these mycotoxins and their producers. The phylogenetic species concept has become a valuable tool to study the global occurrence of mycotoxin-producing Fusarium species. This has revolutionised our views on the terrestrial distribution of trichothecene-producing Fusaria in the context of agronomics, climatic conditions, and human interference by the global trade and exchange of agricultural commodities. This paper presents an overview of the dynamics of the different trichothecene-producing Fusarium species as well as their chemotypes and genotypes across different continents. Clearly not one global population exists, but separate ones can be distinguished, sometimes even sympatric in combination with different hosts. A population with more pathogenic strains and chemotypes can replace another. Several displacement events appear to find their origin in the inadvertent introduction of new genotypes into new regions: 3-acetyl-DON-producing F. graminearum in Canada; 3-acetyl-DON-producing F. asiaticum in Eastern China; 15-acetyl-DON F. graminearum in Uruguay; and NIV-producing F asiaticum in the southern United States. PMID:25530109

  9. Biogeography of Fusarium graminearum species complex and chemotypes: a review

    PubMed Central

    van der Lee, Theo; Zhang, Hao; van Diepeningen, Anne; Waalwijk, Cees

    2015-01-01

    Differences in the geographic distribution of distinct trichothecene mycotoxins in wheat and barley were first recorded two decades ago. The different toxicological properties of deoxynivalenol (DON), nivalenol (NIV) and their acetylated derivatives require careful monitoring of the dynamics of these mycotoxins and their producers. The phylogenetic species concept has become a valuable tool to study the global occurrence of mycotoxin-producing Fusarium species. This has revolutionised our views on the terrestrial distribution of trichothecene-producing Fusaria in the context of agronomics, climatic conditions, and human interference by the global trade and exchange of agricultural commodities. This paper presents an overview of the dynamics of the different trichothecene-producing Fusarium species as well as their chemotypes and genotypes across different continents. Clearly not one global population exists, but separate ones can be distinguished, sometimes even sympatric in combination with different hosts. A population with more pathogenic strains and chemotypes can replace another. Several displacement events appear to find their origin in the inadvertent introduction of new genotypes into new regions: 3-acetyl-DON-producing F. graminearum in Canada; 3-acetyl-DON-producing F. asiaticum in Eastern China; 15-acetyl-DON F. graminearum in Uruguay; and NIV-producing F asiaticum in the southern United States. PMID:25530109

  10. Does biopolymers composition in seeds contribute to the flax resistance against the Fusarium infection?

    PubMed

    Zeitoun, Ahmed M; Preisner, Marta; Kulma, Anna; Dymi?ska, Lucyna; Hanuza, Jerzy; Starzycki, Michal; Szopa, Jan

    2014-01-01

    Over the last decades, the cultivation of fibrous flax declined heavily. There are number of reasons for that fact; one of them is flax susceptibility to the pathogen infection. Damages caused mainly by fungi from genus Fusarium lead to the significant losses when cultivating flax, which in turn discourage farmers to grow flax. Therefore, to launch the new products from flax with attractive properties there is a need to obtain new flax varieties with increased resistance to pathogens. In order to obtain the better quality of flax fiber, we previously generated flax with reduced pectin or lignin level (cell wall polymers). The modifications altered also plants' resistance to the Fusarium infection. Undoubtedly, the plant defense system is complex, however, in this article we aimed to investigate the composition of modified flax seeds and to correlate it with the observed changes in the flax resistance to the pathogen attack. In particular, we evaluated the content and composition of carbohydrates (cell wall polymers: pectin, cellulose, hemicelluloses and mucilage), and phenylpropanoid compounds (lignin, lignans, phenolics). From the obtained results we concluded that the observed changes in the vulnerability to pathogens putatively correlate with the antioxidant potential of phenylpropanoids accumulated in seeds, seco-isolariciresinol and coumaric acid diglycosides in particular, and with pectin level as a carbon source for pathogens. Surprisingly, relatively less important for the resistance was the physical barrier, including lignin and cellulose amount and cellulose structure. Certainly, the hypothesis should be verified on a larger number of genotypes. PMID:25080398

  11. Prussin et. al. 1 Agricultural and Forest Meteorology Experimental Validation of a Long-Distance Transport Model for Plant Pathogens:1

    E-print Network

    Ross, Shane

    -Distance Transport Model for Plant Pathogens:1 Application to Fusarium graminearum2 Aaron J. Prussin, II1 plant pathogen that may be transported through the atmosphere over long25 distances. A Gaussian dispersal model has been developed to predict the long distance26 transport of plant pathogens

  12. [Biodegradation of agricultural plant residues by Fusarium oxysporum strains].

    PubMed

    Chepchak, T P; Kurchenko, I N; Iur'eva, E M

    2014-01-01

    The cellulolytic and endoglucanase activity of Fusarium oxysporum strains isolated from soil and plants in the media with plant waste as carbon source has been studied. It was established that the majority of studied strains were able to hydrolyze the filter paper, husk of sunflower seeds, wheat straw and corn stalks. Cellulolytic activity depended on the strain of microscopic fungi, type of substrate and duration of cultivation. The maximum cellulase activity 1 U/ml and the concentration of reducing sugars -0.875 mg/ml were found in soil strain F. oxysporum 420 in the medium with corn stalks. Endoglucanase activity of plant pathogenic strains was higher than that of soil ones. PMID:25199344

  13. GENETIC CONTROL OF TRICHOTHECENE BIOSYNTHESIS IN FUSARIUM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The biosynthesis of trichothecenes involves a complex pathway that begins with the sesquiterpene hydrocarbon trichodiene and consists of multiple oxygenation, cyclization, and esterification steps. Twelve genes required for trichothecene biosynthesis in Fusarium are clustered within a 26-kb segment...

  14. Brachypodium distachyon: a new pathosystem to study Fusarium head blight and other Fusarium diseases of wheat

    PubMed Central

    2011-01-01

    Background Fusarium species cause Fusarium head blight (FHB) and other important diseases of cereals. The causal agents produce trichothecene mycotoxins such as deoxynivalenol (DON). The dicotyledonous model species Arabidopsis thaliana has been used to study Fusarium-host interactions but it is not ideal for model-to-crop translation. Brachypodium distachyon (Bd) has been proposed as a new monocotyledonous model species for functional genomic studies in grass species. This study aims to assess the interaction between the most prevalent FHB-causing Fusarium species and Bd in order to develop and exploit Bd as a genetic model for FHB and other Fusarium diseases of wheat. Results The ability of Fusarium graminearum and Fusarium culmorum to infect a range of Bd tissues was examined in various bioassays which showed that both species can infect all Bd tissues examined, including intact foliar tissues. DON accumulated in infected spike tissues at levels similar to those of infected wheat spikes. Histological studies revealed details of infection, colonisation and host response and indicate that hair cells are important sites of infection. Susceptibility to Fusarium and DON was assessed in two Bd ecotypes and revealed variation in resistance between ecotypes. Conclusions Bd exhibits characteristics of susceptibility highly similar to those of wheat, including susceptibility to spread of disease in the spikelets. Bd is the first reported plant species to allow successful infection on intact foliar tissues by FHB-causing Fusarium species. DON appears to function as a virulence factor in Bd as it does in wheat. Bd is proposed as a valuable model for undertaking studies of Fusarium head blight and other Fusarium diseases of wheat. PMID:21639892

  15. Screening and functional analysis of the peroxiredoxin specifically expressed in Bursaphelenchus xylophilus--the causative agent of pine wilt disease.

    PubMed

    Fu, Han-Yu; Ren, Jia-Hong; Huang, Lin; Li, Hao; Ye, Jian-Ren

    2014-01-01

    The pine wood nematode, Bursaphelenchus xylophilus, is the causal agent of pine wilt disease. Accurately differentiating B. xylophilus from other nematodes species, especially its related species B. mucronatus, is important for pine wood nematode detection. Thus, we attempted to identify a specific protein in the pine wood nematode using proteomics technology. Here, we compared the proteomes of B. xylophilus and B. mucronatus using Two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption/ionization -time-of-flight/time-of-flight (MALDI-TOF/TOF-MS) technologies. In total, 15 highly expressed proteins were identified in B. xylophilus compared with B. mucronatus. Subsequently, the specificity of the proteins identified was confirmed by PCR using the genomic DNA of other nematode species. Finally, a gene encoding a specific protein (Bx-Prx) was obtained. This gene was cloned and expressed in E. coli. The in situ hybridisation pattern of Bx-Prx showed that it was expressed strongly in the tail of B. xylophilus. RNAi was used to assess the function of Bx-Prx, the results indicated that the gene was associated with the reproduction and pathogenicity of B. xylophilus. This discovery provides fundamental information for identifying B. xylophilus via a molecular approach. Moreover, the purified recombinant protein has potential as a candidate diagnostic antigen of pine wilt disease, which may lead to a new immunological detection method for the pine wood nematode. PMID:24918285

  16. FUSARIUM GRAMINEARUM - INDUCED DIFFERENTIAL GENE EXPRESSION BETWEEN FUSARIUM HEAD BLIGHT-RESISTANT AND SUSCEPTIBLE WHEAT CULTIVARS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight (FHB), primarily caused by Fusarium graminearum Schw., is a destructive disease of wheat (Triticum aestivum L.). Although several genes related to FHB resistance have been reported, global analysis of gene expression in response to FHB infection remains to be explored. The expre...

  17. Fusarium-damaged kernels and deoxynivalenol in Fusarium-infected U.S. Winter Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight (FHB) is a devastating disease that threatens wheat (Triticum aestivum L.) production in many areas worldwide. FHB infection results in Fusarium-damaged kernels (FDK) and deoxynivalenol (DON) that dramatically reduce grain yield and quality. More effective and accurate disease e...

  18. Effect of Trichothecenes Produced by Fusarium graminearum during Fusarium Head Blight Development in Six Cereal Species

    Microsoft Academic Search

    François Langevin; François Eudes; André Comeau

    2004-01-01

    Fusarium head blight (FHB) is a complex cereal disease associated with trichothecene production; these mycotoxins are factors of aggressiveness in wheat. Six species (bread and durum wheat, triticale, rye, barley and oats) were submitted to point inoculations with two isogenic strains of Fusarium graminearum; a wild strain (Tri5 +) produced trichothecenes and the mutated strain (Tri5 -) did not. The

  19. Sequence composition and mapping of BACs of cotton homoeologous chromosomes 11 and 21

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interest in cotton chromosome 11 and its homoeologous chromosome 21 derives from the discovery of resistance (R) or pathogen-induced R genes underlying QTLs involved in root-knot nematode, reniform nematode, Fusarium wilt, Verticillium wilt, and black root rot resistance. Genetic and QTL mapping eff...

  20. Effects of Fusarium solani and F. oxysporum Infection on the Metabolism of Ginsenosides in American Ginseng Roots.

    PubMed

    Jiao, Xiaolin; Lu, Xiaohong; Chen, Amanda Juan; Luo, Yi; Hao, Jianjun J; Gao, Weiwei

    2015-01-01

    American ginseng (Panax quinquefolius L.) is a highly valuable herb widely used for medicinal treatments. Its pharmacologically important compounds are the ginsenosides, which are secondary metabolites in American ginseng root. The concentrations of ginsenoside in roots can be changed by fungal infection, but it is unclear what specific root tissues are impacted and whether the change is systemic. In this study, American ginseng roots were inoculated with two fungal pathogens (Fusarium solani or F. oxysporum) and the levels of six ginsenosides (Rb1, Rb2, Rc, Rd, Re, and Rg1) were then measured in the phloem and xylem around the discolored lesions and adjacent healthy areas of the root. Results indicated that the growth of Fusarium spp. was strictly limited to phloem, and correspondingly the ginsenoside concentration was only altered in this infected phloem. The concentration of Rg1, Rd, and Rc significantly changed in phloem tissues where F. solani was inoculated, while only Rg1 and Rd changed significantly after F. oxysporum inoculation. However, no changes of any ginsenoside occurred in either xylem or phloem tissue adjacent to the inoculation point. In addition, when two Fusarium spp. were grown on ginsenoside-amended Czapek medium, the majority of ginsenosides were depleted. Therefore, pathogenic Fusarium spp. may reduce ginsenoside levels by consuming them. PMID:26060917

  1. New species of Fusarium associated with dieback of Spartina alterniflora in Atlantic salt marshes.

    PubMed

    Elmer, Wade H; Marra, Robert E

    2011-01-01

    Sudden vegetation dieback (SVD) is the loss of smooth cordgrass (Spartina alterniflora) along intertidal creeks in salt marshes of the Atlantic and Gulf states. The underlying cause of SVD remains unclear, but earlier work suggested a contributing role for Fusarium spp. in Louisiana. This report investigated whether these or other Fusarium species were associated with S. alterniflora dieback in mid- to north-Atlantic states. Isolations from seven SVD sites yielded 192 isolates of Fusarium spp., with more than 75% isolated from aboveground tissue. Most isolates (88%) fell into two undescribed morphospecies (MS) distinguished from each other by macroconidial shape, phialide ontogeny and growth rates. Pathogenicity tests on wound-inoculated S. alterniflora stems and seedling roots revealed that isolates in MS1 were more virulent than those in MS2 but no single isolate caused plant mortality. No matches to known species of Fusarium were revealed by DNA sequence queries of translation elongation factor 1-? (tef1) sequences. A phylogenetic analysis of partial sequences of three genes, ?-tubulin (?-tub), calmodulin (cal) and tef1, was conducted on representative isolates from MS1 (n = 20) and MS2 (n = 18); it provided strong evidence that the MS1 isolates form a clade that represents a heretofore undescribed species, which we designate Fusarium palustre sp. nov. Isolates from the more variable MS2 clustered with the F. incarnatum-equiseti species complex as F. cf. incarnatum. Although a strong association exists between both species and declining S. alterniflora in SVD sites, neither appears to play a primary causal role in SVD. However, our findings suggest that F. palustre might play an important secondary role in the ecological disruption of the salt marshes. PMID:21471289

  2. Molecular Inversion Probe: A New Tool for Highly Specific Detection of Plant Pathogens

    PubMed Central

    Trau, Matt; Botella, Jose R.

    2014-01-01

    Highly specific detection methods, capable of reliably identifying plant pathogens are crucial in plant disease management strategies to reduce losses in agriculture by preventing the spread of diseases. We describe a novel molecular inversion probe (MIP) assay that can be potentially developed into a robust multiplex platform to detect and identify plant pathogens. A MIP has been designed for the plant pathogenic fungus Fusarium oxysporum f.sp. conglutinans and the proof of concept for the efficiency of this technology is provided. We demonstrate that this methodology can detect as little as 2.5 ng of pathogen DNA and is highly specific, being able to accurately differentiate Fusarium oxysporum f.sp. conglutinans from other fungal pathogens such as Botrytis cinerea and even pathogens of the same species such as Fusarium oxysporum f.sp. lycopersici. The MIP assay was able to detect the presence of the pathogen in infected Arabidopsis thaliana plants as soon as the tissues contained minimal amounts of pathogen. MIP methods are intrinsically highly multiplexable and future development of specific MIPs could lead to the establishment of a diagnostic method that could potentially screen infected plants for hundreds of pathogens in a single assay. PMID:25343255

  3. Tomato immune receptor Ve1 recognizes effector of multiple fungal pathogens uncovered by genome and RNA sequencing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fungal plant pathogens secrete effector molecules to establish disease on their hosts, while plants in turn utilize immune receptors to intercept these effectors. The tomato immune receptor Ve1 governs resistance to race 1 strains of the soil-borne vascular wilt fungi Verticillium dahliae and V. alb...

  4. Population Structure and Genetic Diversity of the Fusarium graminearum Species Complex

    PubMed Central

    Wang, Jian-Hua; Ndoye, Mbacke; Zhang, Jing-Bo; Li, He-Ping; Liao, Yu-Cai

    2011-01-01

    The Fusarium graminearum species complex (Fg complex) consists of phylogenetically distinct species some of which cannot be discriminated based on their morphology. Their chemotypes and geographic distributions are dramatically different, and these highlight the challenges that Fusarium head blight (FHB) poses to plant disease specialists and plant breeders, thereby requiring that quarantine officials employ molecular diagnostic tools in their active surveillance programs. Molecular marker technologies play essential roles in species identification of the Fg complex, and they are being used widely to assess the genetic diversity of the clade. The utility, applicability and limitations of molecular methods for assessing the population structure and genetic diversity within the Fg complex are discussed with suitable examples. Knowledge gained from these studies will provide a baseline for monitoring changes in FHB pathogen diversity and mycotoxin potential over time, both of which are critical to the ultimate control and elimination of this economically devastating disease. PMID:22069755

  5. Molecular variability among isolates of Fusarium oxysporum associated with root rot disease of Agave tequilana.

    PubMed

    Vega-Ramos, Karla L; Uvalle-Bueno, J Xavier; Gómez-Leyva, Juan F

    2013-04-01

    In this study, 115 isolates of Fusarium oxysporum from roots of Agave tequilana Weber cv azul plants and soil in commercial plantations in western Mexico were characterized using morphological and molecular methods. Genetic analyses of monosporic isolates included restriction enzyme analysis of rDNA (ARDRA) using HaeIII and HinfI, and genetic diversity was determined using Box-PCR molecular markers. Box-PCR analysis generated 14 groups. The groups correlated highly with the geographic location of the isolate and sample type. These results demonstrate the usefulness of ARDRA and Box-PCR techniques in the molecular characterization of the Fusarium genus for the discrimination of pathogenic isolates. PMID:23315087

  6. Cross-infection potential of crown rot pathogen ( Lasiodiplodia theobromae ) isolates and their management using potential native bioagents in banana

    Microsoft Academic Search

    R. Thangavelu; G. Sangeetha; M. M. Mustaffa

    2007-01-01

    Crown rot infected banana samples collected from different regions of India revealed that the fungus Lasiodiplodia theobromae was the major pathogen responsible for crown rot and Colletotrichum musae and Fusarium spp. were the minor pathogens. The cross-inoculation experiment, conducted using five different virulent isolates of L. theobromae on five different commercial cultivars of banana, demonstrated that generally the isolates were

  7. The influence of bacterial and fungal isolates from the rhizosphere of Tamcot CAMD-E on host response to Phymatotrichum root rot of cotton 

    E-print Network

    Lazo, Gerard Raymond

    1984-01-01

    of certain soil microbes; some commonly mentioned ones are species of Arthrobacter spp. , Pseudomonas spp. , and Chromobacterium spp. (61). Experiments with Fusarium-wilt suppressing soils suggested that competition between saprophytic and pathogenic... rhizosphere, had a 50% reduction in damping-off caused by Rhizoctonia solani (42). In another series of experiments bacterial treatments of carnation were found to reduce the incidence of Fusarium wilt (54). Other modes of protection, such as growth...

  8. Species-Specific Detection and Identification of Fusarium Species Complex, the Causal Agent of Sugarcane Pokkah Boeng in China

    PubMed Central

    Que, Youxiong; Wang, Jihua; Comstock, Jack C.; Wei, Jinjin; McCord, Per H.; Chen, Baoshan; Chen, Rukai; Zhang, Muqing

    2014-01-01

    Background Pokkah boeng disease caused by the Fusarium species complex results in significant yield losses in sugarcane. Thus, the rapid and accurate detection and identification of the pathogen is urgently required to manage and prevent the spreading of sugarcane pokkah boeng. Methods A total of 101 isolates were recovered from the pokkah boeng samples collected from five major sugarcane production areas in China throughout 2012 and 2013. The causal pathogen was identified by morphological observation, pathogenicity test, and phylogenetic analysis based on the fungus-conserved rDNA-ITS. Species-specific TaqMan real-time PCR and conventional PCR methods were developed for rapid and accurate detection of the causal agent of sugarcane pokkah boeng. The specificity and sensitivity of PCR assay were also evaluated on a total of 84 isolates of Fusarium from China and several isolates from other fungal pathogens of Sporisorium scitamineum and Phoma sp. and sugarcane endophyte of Acremonium sp. Result Two Fusarium species (F. verticillioides and F. proliferatum) that caused sugarcane pokahh boeng were identified by morphological observation, pathogenicity test, and phylogenetic analysis. Species-specific TaqMan PCR and conventional PCR were designed and optimized to target their rDNA-ITS regions. The sensitivity of the TaqMan PCR was approximately 10 pg of fungal DNA input, which was 1,000-fold over conventional PCR, and successfully detected pokkah boeng in the field-grown sugarcane. Conclusions/Significance This study was the first to identify two species, F. verticillioides and F. proliferatum, that were causal pathogens of sugarcane pokkah boeng in China. It also described the development of a species-specific PCR assay to detect and confirm these pathogens in sugarcane plants from mainland China. This method will be very useful for a broad range of research endeavors as well as the regulatory response and management of sugarcane pokkah boeng. PMID:25141192

  9. Fusarium head blight and mycotoxin contamination of wheat, a review

    Microsoft Academic Search

    C. H. A. Snijders

    1990-01-01

    Summary An infection of bread wheat by fusarium head blight contaminates the crop with mycotoxins, particularly deoxynivalenol (DON) and nivalenol (NIV). The toxicity and natural occurrence of these mycotoxins in wheat are reviewed. Based on 8 years data of fusarium head blight epidemics of wheat in the Netherlands, DON contamination of the grain was estimated. Fusarium head blight ratings averaged

  10. Effect of chloropicrin fumigation on microbial communities evaluated by community-level physiological profile and the resistance against fusarium wilt

    Microsoft Academic Search

    Kazuhito Itoh; Daisuke Goto; Kaoru Sueyasu; Kousuke Suyama; Hiroki Yamamoto

    2002-01-01

    Different microbial communities characterized by the Biolog pattern were developed in the rhizosphere of radish grown on a rockwool hydroponic system treated with chloropicrinfumigated and non-fumigated soil suspensions although no differences were observed in their viable counts. Different microbial communities also were developed in the rhizosphere and non-rhizosphere. After the development of microbial communities in the rhizosphere, bud cells of

  11. Identification and Chacterization of new strains of Enterobacter spp. causing Mulberry (Morus alba) wilt disease in China

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new mulberry wilt disease (MWD) was recently identified in Hangzhou, Zhejiang province, China. Typical symptoms of the disease are dark brown discolorations in vascular tissues, leaf wilt, defoliation, and tree decline. Unlike the bacterial wilt disease caused by Ralstonia solanacearum, the leaf w...

  12. Dissection of the fusarium I2 gene cluster in tomato reveals six homologs and one active gene copy.

    PubMed

    Simons, G; Groenendijk, J; Wijbrandi, J; Reijans, M; Groenen, J; Diergaarde, P; Van der Lee, T; Bleeker, M; Onstenk, J; de Both, M; Haring, M; Mes, J; Cornelissen, B; Zabeau, M; Vos, P

    1998-06-01

    The I2 locus in tomato confers resistance to race 2 of the soil-borne fungus Fusarium oxysporum f sp lycopersici. The selective restriction fragment amplification (AFLP) positional cloning strategy was used to identify I2 in the tomato genome. A yeast artificial chromosome (YAC) clone covering approximately 750 kb encompassing the I2 locus was isolated, and the AFLP technique was used to derive tightly linked AFLP markers from this YAC clone. Genetic complementation analysis in transgenic R1 plants using a set of overlapping cosmids covering the I2 locus revealed three cosmids giving full resistance to F. o. lycopersici race 2. These cosmids shared a 7-kb DNA fragment containing an open reading frame encoding a protein with similarity to the nucleotide binding site leucine-rich repeat family of resistance genes. At the I2 locus, we identified six additional homologs that included the recently identified I2C-1 and I2C-2 genes. However, cosmids containing the I2C-1 or I2C-2 gene could not confer resistance to plants, indicating that these members are not the functional resistance genes. Alignments between the various members of the I2 gene family revealed two significant variable regions within the leucine-rich repeat region. They consisted of deletions or duplications of one or more leucine-rich repeats. We propose that one or both of these leucine-rich repeats are involved in Fusarium wilt resistance with I2 specificity. PMID:9634592

  13. Isolation, evaluation and characterization of Bacillus subtilis from cotton rhizospheric soil with biocontrol activity against Fusarium oxysporum.

    PubMed

    Gajbhiye, Archana; Rai, Alok R; Meshram, Sudhir U; Dongre, A B

    2010-07-01

    Present investigation is based on the isolation of Bacillus subtilis from cotton rhizosphere and their evaluation as biocontrol agent against Fusarium oxysporum. The production of extracellular hydrolytic enzyme was studied for determining the antagonism. 43% of 21 isolates were identified under the B. subtilis group on the basis of biochemical characterization. 38% isolates showed competitive activity against Fusarium oxysporum and exhibit more than 50% mycelial inhibition in dual culture bioassay. The pot assay of cotton by seed treatment and soil amendment technique under green house condition showed the competent activity of the isolates in preventing the wilting of cotton seedlings due to F. oxysporum infection. SVI values of 30 day old seedlings indicated that the soil inoculation with B. subtilis BP-2 and seed treatment with B. subtilis BP-9 significantly promoted the growth of cotton seedlings. RAPD profiling revealed the diversity in the Bacillus subtilis group, ranging from 10 to 32%. The discriminative pattern among the isolates belonging to the same species was validated by 16S rDNA partial sequencing which identified them into four different strains of B. subtilis. PMID:24026922

  14. Laurel wilt: An unusual and destructive disease of American members of the Lauraceae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Laurel wilt kills American members of the Lauraceae plant family (Laurales, Magnoliid complex). These include significant components of Coastal Plain forest communities in the SE USA, most importantly redbay (Persea borbonia), as well as the commercial crop avocado (P. americana). Laurel wilt is cau...

  15. The influence of wilting on wheat silage G. ASHBELL, H.H.THEUNE D. SKLAN

    E-print Network

    Paris-Sud XI, Université de

    The influence of wilting on wheat silage G. ASHBELL, H.H.THEUNE D. SKLAN Agricultural Research Organization, The Volcani Center, P.O. Box 6, Bet Dagan 50250, Israel SUMMARY Wheat plants at shooting and flowering maturation stages were cut and wilted to 36 °7o dry matter (DM). The wheat was ensiled for 90 days

  16. Genetic variation among Fusarium isolates from onion, and resistance to Fusarium basal rot in related Allium species

    Microsoft Academic Search

    Guillermo A. Galván; Carole F. S. Koning-Boucoiran; Wim J. M. Koopman; Karin Burger-Meijer; Pablo H. González; Cees Waalwijk; Chris Kik; Olga E. Scholten

    2008-01-01

    The aim of this research was to study levels of resistance to Fusarium basal rot in onion cultivars and related Allium species, by using genetically different Fusarium isolates. In order to select genetically different isolates for disease testing, a collection of 61 Fusarium isolates, 43 of them from onion (Allium cepa), was analysed using amplified fragment length polymorphism (AFLP) markers.

  17. Biological control of bacterial wilt in Arabidopsis thaliana involves abscissic acid signalling.

    PubMed

    Feng, Dong Xin; Tasset, Céline; Hanemian, Mathieu; Barlet, Xavier; Hu, Jian; Trémousaygue, Dominique; Deslandes, Laurent; Marco, Yves

    2012-06-01

    Means to control bacterial wilt caused by the phytopathogenic root bacteria Ralstonia solanacearum are limited. Mutants in a large cluster of genes (hrp) involved in the pathogenicity of R. solanacearum were successfully used in a previous study as endophytic biocontrol agents in challenge inoculation experiments on tomato. However, the molecular mechanisms controlling this resistance remained unknown. We developed a protection assay using Arabidopsis thaliana as a model plant and analyzed the events underlying the biological control by genetic, transcriptomic and molecular approaches. High protection rates associated with a significant decrease in the multiplication of R. solanacearum were observed in plants pre-inoculated with a ?hrpB mutant strain. Neither salicylic acid, nor jasmonic acid/ethylene played a role in the establishment of this resistance. Microarray analysis showed that 26% of the up-regulated genes in protected plants are involved in the biosynthesis and signalling of abscissic acid (ABA). In addition 21% of these genes are constitutively expressed in the irregular xylem cellulose synthase mutants (irx), which present a high level of resistance to R. solanacearum. We propose that inoculation with the ?hrpB mutant strain generates a hostile environment for subsequent plant colonization by a virulent strain of R. solanacearum. PMID:22432714

  18. An outbreak of Fusarium head blight of durum wheat on the Liverpool Plains in northern New South Wales in 1999

    Microsoft Academic Search

    R. J. Southwell; K. J. Moore; W. Maiming; P. T. Hayman

    2003-01-01

    In 1999, a serious outbreak of Fusarium head blight occurred in durum wheat crops on the Liverpool Plains of northern New\\u000a South Wales. Disease incidence in individual crops ranged from 2 to 100%. Gibberella zeae was the predominant pathogen. Analysis of weather records showed that in 1999, wheat flowered in an unusually wet and warm\\u000a spring thus suggesting weather as

  19. A Conserved Homeobox Transcription Factor Htf1 Is Required for Phialide Development and Conidiogenesis in Fusarium Species

    PubMed Central

    Zheng, Wenhui; Zhao, Xu; Xie, Qiurong; Huang, Qingping; Zhang, Chengkang; Zhai, Huanchen; Xu, Liping; Lu, Guodong; Shim, Won-Bo; Wang, Zonghua

    2012-01-01

    Conidia are primary means of asexual reproduction and dispersal in a variety of pathogenic fungi, and it is widely recognized that they play a critical role in animal and plant disease epidemics. However, genetic mechanisms associated with conidiogenesis are complex and remain largely undefined in numerous pathogenic fungi. We previously showed that Htf1, a homeobox transcription factor, is required for conidiogenesis in the rice pathogen Magnaporthe oryzae. In this study, our aim was to characterize how Htf1 homolog regulates common and also distinctive conidiogenesis in three key Fusarium pathogens: F. graminearm, F. verticillioides, and F. oxysporum. When compared to wild-type progenitors, the gene-deletion mutants in Fusarium species failed to form conventional phialides. Rather, they formed clusters of aberrant phialides that resembled elongated hyphae segments, and it is conceivable that this led to the obstruction of conidiation in phialides. We also observed that mutants, as well as wild-type Fusaria, can initiate alternative macroconidia production directly from hyphae through budding-like mechanism albeit at low frequencies. Microscopic observations led us to conclude that proper basal cell division and subsequent foot cell development of macroconidia were negatively impacted in the mutants. In F. verticillioides and F. oxysporum, mutants exhibited a 2- to 5- microconidia complex at the apex of monophialides resulting in a floral petal-like shape. Also, prototypical microconidia chains were absent in F. verticillioides mutants. F. graminearum and F. verticillioides mutants were complemented by introducing its native HTF1 gene or homologs from other Fusarium species. These results suggest that Fusarium Htf1 is functionally conserved homeobox transcription factor that regulates phialide development and conidiogenesis via distinct signaling pathways yet to be characterized in fungi. PMID:23029006

  20. Limitations of exotic and indigenous isolates of Fusarium avenaceum for the biological control of spotted knapweed — Centaurea maculosa

    Microsoft Academic Search

    E. Czembor; G. A. Strobel

    1997-01-01

    Three isolates ofFusarium avenaceum are pathogenic on spotted knapweed(Centaurea maculosa), a major weed plant of pasturelands and rangelands of the Pacific Northwestern USA. One isolate (no. 1) obtained from the\\u000a European centre of origin of knapweed and isolate no. 365 native to Montana, did not significantly affect knapweed seed germination.\\u000a However,F. avenaceum no. 1003, another Montana native isolate, caused a