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1.
G. Gilardi S. Franco Ortega P. C. J. van Rijswick G. Ortu M. L. Gullino A. Garibaldi 《Plant pathology》2017,66(4):677-688
Fusarium oxysporum f. sp. lactucae, the causal agent of fusarium wilt of lettuce (Lactuca sativa), occurs in most countries in which lettuce is grown and causes serious economic losses. Three races (1, 2 and 3) of the pathogen have previously been identified on the basis of their ability to cause disease on differential lettuce cultivars, as well as by means of molecular tools developed to characterize different races of this pathogen. Only race 1 has been detected in Europe so far. In this study, two isolates of F. oxysporum, obtained from lettuce plants grown in the Netherlands showing symptoms of wilt, have been characterized by combining the study of pathogenicity with differential cultivars of lettuce and molecular assays to determine whether the isolates are different from the known races of F. oxysporum f. sp. lactucae. This study reports the presence of F. oxysporum f. sp. lactucae for the first time in the Netherlands. The causal pathogen has been identified, using the IRAP‐SCAR technique, as a new race of F. oxysporum f. sp. lactucae. Specific primers have been designed to identify this new race. 相似文献
2.
Four-hundred-sixty-eightFusarium andFusarium-like isolates were obtained from crowns and subcrown internodes of winter wheat grown in Erzurum, Turkey. Of these isolates,
34.8% wereFusarium acuminatum, 32.3% wereF. equiseti, 16.9% wereF. oxysporum, 15.0% wereMicrodochium nivale (formerlyFusarium nivale), 0.6% wereF. tabacinum and 0.4% wereF. solani. In pathogenicity tests on wheat, the highest disease severity was caused by isolates ofM. nivale, whereas isolates ofF. acuminatum, F. equiseti, F. oxysporum andF. solani were slightly virulent; isolates ofF. tabacinum were nonpathogenic. This is the first report ofM. nivale andF. tabacinum from wheat in Turkey.
http://www.phytoparasitica.org posting Jan. 29, 2003. 相似文献
3.
Masato?Kawabe Kohei?Mizutani Takanobu?Yoshida Tohru?Teraoka Katsuyoshi?Yoneyama Isamu?Yamaguchi Tsutomu?Arie
We selected a reduced-pathogenicity mutant of Fusarium oxysporum f. sp. lycopersici, a tomato wilt pathogen, from the transformants generated by restriction enzyme-mediated integration (REMI) transformation. The gene tagged with the plasmid in the mutant was predicted to encode a protein of 321 amino acids and was designated FPD1. Homology search showed its partial similarity to a chloride conductance regulatory protein of Xenopus, suggesting that FPD1 is a transmembrane protein. Although the function of FPD1 has not been identified, it does participate in the pathogenicity of F. oxysporum f. sp. lycopersici because FPD1-deficient mutants reproduced the reduced pathogenicity on tomato.The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession number AB110097 相似文献
4.
Five experimental trials were carried out to test different biological control agents against Fusarium wilt of lettuce, cause
byFusarium oxysporum f.sp.lactucae. In the presence of a very high disease incidence, the best results in terms of disease control as well as increased growth
response were shown byTrichoderma harzianum T 22 (RootShield), which, at 3 gl
−1 of substrate, provided very consistent results.F. oxysporum IF 23 gave good disease control but in two out of five trials reduced the biomass produced. Less consistent, but still significant
results were provided byF oxysporium MSA 25, at 3 gl
−1 of substrate, and byTrichoderma viride TV 1. The twoF. oxysporum agents Fo 251/2 and Fo 47 and the mixture ofT. harzianum + T. viride (Remedier) partially reduced disease incidence but were less effective than the above mentioned. Less interesting results
were offered byStreptomyces griseoviridis (Mycostop). The results obtained show that biological control can play a role in the management of Fusarium wilt of lettuce. 相似文献
5.
Fusarium wilt is an economically important fungal disease of common eggplant (Solanum melongena) cultivated in the eastern Mediterranean region of Turkey. Seventy-four isolates of Fusarium oxysporum isolated from diseased eggplant displaying typical Fusarium wilt symptoms were screened for pathogenicity on the highly susceptible
cv. ‘Pala’. All the isolates tested were pathogenic to eggplant and designated as Fusarium oxysporum f. sp. melongenae (Fomg). Genetic diversity among a core set of 20 Fomg isolates that were selected based upon geographic locations, were characterized by using pathogenicity, vegetative compatibility
grouping (VCG), and random amplified polymorphic DNA (RAPD) analysis. The area under the disease progress curve (AUDPC) was
calculated for each Fomg isolate until 21 days after inoculation (DAI). The most virulent isolate was identified as Fomg10 based on AUDPC, disease severity and vascular discoloration measurements at 21 DAI. At this date, a good correlation was
observed between disease severity and AUDPC values for all isolates (r = 0.73). UPGMA (unweighted pair group method with arithmetic average) cluster analysis of RAPD data using Dice’s coefficient
of similarity differentiated all the Fomg isolates tested, and indicated considerable genetic variation among Fomg isolates, but isolates from the same geographic region were grouped together. There was no direct correlation between clustering
in the RAPD dendrogram and pathogenicity testing of Fomg isolates. Twenty isolates of Fomg were assigned to VCG 0320. 相似文献
6.
N. Mohammadi H. Puralibaba E. Mohammadi Goltapeh A. Babaie Ahari B. Pakdaman Sardrood 《Phytoparasitica》2012,40(1):69-76
Fusarium oxysporum f. sp. lentis is the most important pathogen of lentil plants, and most areas under lentil cultivation are reported to have a fusarium
wilt disease background. The plants are infected in the seedling stage and later stages of their development. Fusarium wilt
disease, which has appeared at high incidence rates during recent years, has caused sharp drops in the yield, especially in
Moghan, in the northwest of Iran. Forty-five isolates of the pathogen were collected from different regions of the country
with two isolates from ICARDA in the summer of 2008 and identified using Nelson’s key. The pathogenicity of the collected
isolates was studied on a sensitive line (ILL 4605) under greenhouse conditions and significant differences in pathogenicity
were found among them. The most pathogenic isolates from three provinces, East Azerbaijan (EA 30), Ardebil (Ar 3) and Khorasan
(Kh 45), were selected and used in screening of 55 developed lines under greenhouse and field conditions. In the greenhouse,
test plants were inoculated by immersing root tips in spore suspension and sowing seeds in pre-infested pot soil. Field tests
were carried out in a naturally highly infested farm. At all stages, the plant response to the disease was based on the percentage
of dead plants. Cluster analyses of the greenhouse and field data led to the selection of three lines (81S15, FLIP2007-42 L
and FLIP2009-18 L) that were resistant under greenhouse and field conditions. 相似文献
7.
Chunyu Li Shi Chen Cunwu Zuo Qingming Sun Qian Ye Ganjun Yi Bingzhi Huang 《European journal of plant pathology / European Foundation for Plant Pathology》2011,131(2):327-340
Fusarium oxysporum f. sp. cubense (Foc) is the causal pathogen of Fusarium wilt of banana. To understand infection of banana roots by Foc race 4, we developed a green fluorescent protein (GFP)-tagged transformant and studied pathogenesis using fluorescence microscopy
and confocal laser scanning microscopy. The transformation was efficient, and GFP expression was stable for at least six subcultures
with fluorescence clearly visible in both hyphae and spores. The transformed Foc isolate also retained its pathogenicity and growth pattern, which was similar to that of the wild type. The study showed
that: (i) Foc race 4 was capable of invading the epidermal cells of banana roots directly; (ii) potential invasion sites include epidermal
cells of root caps and elongation zone, and natural wounds in the lateral root base; (iii) in banana roots, fungal hyphae
were able to penetrate cell walls directly to grow inside and outside cells; and (iv) fungal spores were produced in the root
system and rhizome. To better understand the interaction between Foc race 4 and bananas, nine banana cultivars were inoculated with the GFP-transformed pathogen. Root exudates from these cultivars
were collected and their effect on conidia of the GFP-tagged Foc race 4 was determined. Our results showed that roots of the Foc race 4-susceptible banana plants were well colonized with the pathogen, but not those of the Foc race 4-resistant cultivars. Root exudates from highly resistant cultivars inhibited the germination and growth of the Fusarium
wilt pathogen; those of moderately resistant cultivars reduced spore germination and hyphal growth, whereas the susceptible
cultivars did not affect fungal germination and growth. The results of this work demonstrated that GFP-tagged Foc race 4 isolates are an effective tool to study plant–fungus interactions that could potentially be used for evaluating resistance
in banana to Foc race 4 by means of root colonization studies. Banana root exudates could potentially also be used to identify cultivars in
the Chinese Banana Germplasm Collection with resistance to the Fusarium wilt pathogen. 相似文献
8.
Norihito Yamauchi Mamoru Satou Jyuichi Shimazu Takashi Shirakawa Seizo Horiuchi 《Journal of General Plant Pathology》2007,73(1):29-34
Race 2 isolates of Fusarium oxysporum f. sp. lactucae have been recognized as biotin auxotrophs and consequently have restricted growth on Puhalla's minimal medium (MM), which
contains no biotin. Biotin-autotrophic isolates were raised from race 2 isolates through cultural mutation that grew as well
on MM as they did on MM supplemented with biotin. These autotrophs were identical to the parental isolates in pathogenicity
on race differential cultivars of lettuce (Patriot, Banchu Red Fire, and Costa Rica No. 4), and thus were designated as race
2. A vegetative compatibility test indicated that the autotrophic isolates fell into the same vegetative compatibility group
as the parents. Culture filtrates of the autotrophs allowed abundant growth of the parental auxotroph on MM, and, through
a competitive enzyme-binding assay, biotin was detected in the culture filtrates. These results suggest that biotin auxotrophy
in the natural race 2 isolates has no direct relation to pathogenicity, qualitatively defined as physiological race, or to
vegetative compatibility. 相似文献
9.
Seed treatments with essential oils (from savory and thyme) and biocontrol agents (Pseudomonas spp. and Fusarium oxysporum) have been evaluated in vivo after dry hot air treatments against Fusarium oxysporum f. sp. basilici on basil seeds. The savory and thyme essential oils showed a significant pathogen control activity because of their innate antifungal activity and because of the seed application method, but the dry hot pre-treatment did not show any obvious effect on the performance of the essential oil treatments. The dry heat treatment improved the Pseudomonas seed dressing effect against F.oxysporum f. sp. basilici, and showed important reductions in plant infection and the disease index on the treated seed plants, without any negative effect on seed germination. However, the pathogen control provided by the heat treatments combined with the application of the biocontrol agents never reached the same performance as the chemical treatments considered as the reference. Thus, short dry heat treatments on basil seeds have been shown to be a valid but complementary seed disinfection method against Fusarium wilt. 相似文献
10.
Maha Laksha Mudiyanselage Chandrika Dissanayake Rumi Kashima Shuhei Tanaka Shin-ichi Ito 《Journal of General Plant Pathology》2009,75(2):125-130
Thirty isolates of Fusarium oxysporum from wilted Welsh onion plants were examined for their diversity in nucleotide sequences of the ribosomal DNA (rDNA) intergenic
spacer (IGS) region and for pathogenicity with regard to five Welsh onion cultivars. Phylogenetic analysis based on the IGS
sequences revealed polyphyletic origins of the isolates and a relationship between phylogeny and pathogenicity; low virulence
isolates differed genetically from those with high and moderate virulence. Mating type analysis revealed that all F. oxysporum isolates were MAT1-1 idiomorphs, suggesting that the pathogens may be clonal in the fields examined. 相似文献
11.
The vascular wilt pathogen Fusarium oxysporum f. sp. melonis causes worldwide yield losses of muskmelon. In this study, we characterized a UV-induced non-pathogenic mutant (strain 4/4) of F. oxysporum f. sp. melonis, previously identified as a potential biological control agent. During comparative analysis of vegetative growth parameters using different carbon sources, mutant strain 4/4 showed a delay in development and secretion of extracellular enzymes, compared to the wild type strain. Amendments of the growth medium with yeast extract, adenine or hypoxanthine, but not guanine, complemented the growth defect of strain 4/4, as well as secretion and partial activity of cellulases and endopolygalacturonases, indicating that the strain is an adenine auxotroph. Incubation of strain 4/4 conidia in adenine solution, prior to inoculation of muskmelon plants, partially restored pathogenicity to the mutant strain. 相似文献
12.
Montserrat Ramírez-Suero Anas Khanshour Yves Martinez Martina Rickauer 《European journal of plant pathology / European Foundation for Plant Pathology》2010,126(4):517-530
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 causal agent of Fusarium wilt in alfalfa. However, a tolerant line, F83005.5, and a susceptible line, A17, could be
distinguished by scoring the disease index. The fungus was transformed with the GFP marker gene and colonisation of the plant
roots was analysed by epifluorescence and confocal microscopy. A slightly atypical pattern of root colonisation was observed,
with massive fungal growth in the cortex. Although colonisation was not significantly different between susceptible and tolerant
plants, the expression of some defence-related genes showed discrimination between both lines. A study with 10 strains from
various host-plants indicated that M. truncatula was a permissive host to F. oxysporum. 相似文献
13.
Carmen Gómez-Lama Cabanás Antonio Valverde-Corredor Encarnación Pérez-Artés 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(4):561-576
Fusarium wilt, caused by Fusarium oxysporum f. sp. dianthi (Fod), is the most important carnation disease worldwide. The knowledge of the diversity of the soil population of the pathogen
is essential for the choice of suitable resistant cultivars. We examined the genetic diversity of Fod isolates collected during the period 1998–2008, originating from soils and carnation plants in the most important growing
areas in Spain. Additionally, we have included some Fod isolates from Italy as a reference. Random amplified polymorphic DNA (RAPD) fragments generated by single-primer PCR were
used to compare the relationship between isolates. UPGMA analysis of the RAPD data separated Fod isolates into three clusters (A, B, and C), and this distribution was more related to aggressiveness than to the race of
the isolates. The results obtained in PCR amplifications using specific primers for race 1 and race 2, and SCAR primers developed
in this work, correlated with the molecular groups previously determined from the RAPD analysis, and provided new molecular
markers for the precise identification of the isolates. Results from successive pathogenicity tests showed that molecular
differences between isolates of the same race corresponded with differences in aggressiveness. Isolates of races 1 and 2 in
cluster A (R1I and R2I isolates) and cluster C (R1-type isolates) were all highly aggressive, whereas isolates of races 1
and 2 in cluster B (R1II and R2II isolates) showed a low aggressiveness profile. The usefulness of the molecular markers described
in this study has been proved in double-blind tests with Fod isolates collected in 2008. Results from this work indicate a change in the composition of the Spanish Fod population over time, and this temporal variation could be related to the continuous change in the commercial carnation cultivars
used by growers. This is the first report of genetic diversity among Fod isolates in the same race. 相似文献
14.
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 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(4):499-512
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. Onion isolates were collected in The Netherlands
(15 isolates) and Uruguay (9 isolates), and received from other countries and fungal collections (19 isolates). From these
isolates, 29 were identified as F. oxysporum, 10 as F. proliferatum, whereas the remaining four isolates belonged to F. avenaceum and F. culmorum. The taxonomic status of the species was confirmed by morphological examination, by DNA sequencing of the elongation factor
1-α gene, and by the use of species-specific primers for Fusarium oxysporum, F. proliferatum, and F. culmorum. Within F. oxysporum, isolates clustered in two clades suggesting different origins of F. oxysporum forms pathogenic to onion. These clades were present in each sampled region. Onion and six related Allium species were screened for resistance to Fusarium basal rot using one F. oxysporum isolate from each clade, and one F. proliferatum isolate. High levels of resistance to each isolate were found in Allium fistulosum and A. schoenoprasum accessions, whereas A. pskemense, A. roylei and A. galanthum showed intermediate levels of resistance. Among five A. cepa cultivars, ‘Rossa Savonese’ was also intermediately resistant. Regarding the current feasibility for introgression, A. fistulosum, A. roylei and A. galanthum were identified as potential sources for the transfer of resistance to Fusarium into onion. 相似文献
15.
The objective of the current study was to characterize Fusarium oxysporum f. sp. radicis-cucumerinum isolates from cucumbers in Turkey in terms of pathogenicity, vegetative compatibility and amplified fragment length polymorphism
(AFLP) variation. In the 2007 and 2008 greenhouse cucumber-growing seasons, surveys were conducted in Adana, Antalya, Hatay
and Mersin provinces of the Mediterranean region of Turkey. Forty-seven fungal isolates of F. oxysporum were recovered from diseased cucumber plants. The pathogenicity of each isolate was tested on cucumber seedlings at the one-true-leaf
stage. Forty of the 47 isolates of F. oxysporum were virulent on cucumber seedlings. Based on disease symptoms, the differential effect of temperatures of 17°C and 29°C
on disease development, and the virulence on cucumber seedlings, these 40 isolates were identified as F. oxysporum f. sp. radicis-cucumerinum. Nitrate non-utilizing mutants were generated on minimal medium containing 1.5% KClO3 and their phenotypes were determined. Mutants in different phenotypic classes were paired on minimal medium; of 40 F. oxysporum f. sp. radicis-cucumerinum isolates, thirty-eight were placed into VCG 0260. Remaining two strains were assigned to VCG 0261. The AFLP primers produced
a total of 180 fragments between 200 and 500 bp in length for the 30 isolates tested. At a genetic similarity of 0.71, the
UPGMA analysis separated the isolates into two distinct clusters. The first cluster, AFLP I, included 28 isolates, of which
all belonged to VCG 0260. Two strains in the second AFLP cluster both belonged to VCG 0261. 相似文献
16.
Maha Laksha Mudiyanselage Chandrika Dissanayake Rumi Kashima Shuhei Tanaka Shin-ichi Ito 《Journal of General Plant Pathology》2009,75(1):37-45
Thirty-two isolates of Fusarium species were obtained from wilted Welsh onion (Allium fistulosum) grown on nine farms from six regions in Japan and identified as F. oxysporum (18 isolates), F. verticillioides (7 isolates), and F. solani (7 isolates). The pathogenicity of 32 isolates was tested on five commercial cultivars of Welsh onion and two cultivars of
bulb onion in a seedling assay in a greenhouse. The Fusarium isolates varied in the degree of disease severity on the cultivars. Five F. oxysporum isolates (08, 15, 17, 22, and 30) had a higher virulence on the cultivars than the other isolates. The host range of these
five isolates was limited to Allium species. Molecular characterization of Fusarium isolates was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the
internal transcribed spacer (ITS) regions of ribosomal DNA. The 32 isolates were grouped into eight types (four types for
F. oxysporum, one for F. verticillioides, and three for F. solani). Restriction patterns of the ITS region were not related to pathogenicity. However, the haplotypes obtained with five enzymes
(RsaI, HinfI, HaeIII, ScrFI, and MspI) and the phylogenetic analysis permitted the discernment of the three Fusarium species. The PCR-RFLP analysis should provide a rapid, simple method for differentiating Fusaruim species isolated from wilted Welsh onion in Japan. 相似文献
17.
Alan T. Dyer Robert H. Johnston Andrew C. Hogg Jeffrey A. Johnston 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(3):387-395
Fusarium species involved in the Fusarium crown rot (FCR) complex affect wheat in every stage of development from seedling to grain
fill. This study was designed to compare the aggressiveness of the FCR complex members including F. culmorum, F. pseudograminearum and F. graminearum in causing seedling blight, decreased plant vigour and crown rot. To assess their relative pathogenicity, two hard red spring
wheat cultivars and two durum wheat cultivars were inoculated in the field with five isolates from each of the three species
for two years. Significant differences in patterns of pathogenicity were identified. In particular, F. culmorum caused greater seedling blight while F. pseudograminearum and F. graminearum caused greater crown rot. Greatest yield reductions were caused by F. pseudograminearum. Cultivar differences were identified with respect to seedling disease and late season crown rot. No interactions were identified
between cultivar performance and isolates or species with which they were challenged. 相似文献
18.
19.
The severity of fusarium wilt is affected by inoculum density in soil, which is expected to decline during intervals when a non‐susceptible crop is grown. However, the anticipated benefits of crop rotation may not be realized if the pathogen can colonize and produce inoculum on a resistant cultivar or rotation crop. The present study documented colonization of roots of broccoli, cauliflower and spinach by Fusarium oxysporum f. sp. lactucae, the cause of fusarium wilt of lettuce. The frequency of infection was significantly lower on all three rotation crops than on a susceptible lettuce cultivar, and the pathogen was restricted to the cortex of roots of broccoli. However, F. oxysporum f. sp. lactucae was isolated from the root vascular stele of 7·4% of cauliflower plants and 50% of spinach plants that were sampled, indicating a greater potential for colonization and production of inoculum on these crops. The pathogen was also recovered from the root vascular stele of five fusarium wilt‐resistant lettuce cultivars. Thus, disease‐resistant plants may support growth of the pathogen and thereby contribute to an increase in soil inoculum density. Cultivars that were indistinguishable based on above‐ground symptoms, differed significantly in the extent to which they were colonized by F. oxysporum f. sp. lactucae. Less extensively colonized cultivars may prove to be superior sources of resistance to fusarium wilt for use in breeding programmes. 相似文献
20.
Robert Czajkowski Grzegorz J. Grabe Jan M. van der Wolf 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(2):263-275
Detailed studies were conducted on the distribution of Pectobacterium carotovorum subsp. carotovorum and Dickeya spp. in two potato seed lots of different cultivars harvested from blackleg-diseased crops. Composite samples of six different
tuber sections (peel, stolon end, and peeled potato tissue 0.5, 1.0, 2.0 and 4.0 cm from the stolon end) were analysed by
enrichment PCR, and CVP plating followed by colony PCR on the resulting cavity-forming bacteria. Seed lots were contaminated
with Dickeya spp. and P. carotovorum subsp. carotovorum (Pcc), but not with P. atrosepticum. Dickeya spp. and Pcc were found at high concentrations in the stolon ends, whereas relatively low densities were found in the peel and
in deeper located potato tissue. Rep-PCR, 16S rDNA sequence analysis and biochemical assays, grouped all the Dickeya spp. isolates from the two potato seed lots as biovar 3. The implications of the results for the control of Pectobacterium and Dickeya spp., and sampling strategies in relation to seed testing, are discussed. 相似文献