scholarly journals Characterization of a Vascular Wilt of Erythroxylum coca Caused by Fusarium oxysporum f. sp. erythroxyli Forma Specialis Nova

Plant Disease ◽  
1997 ◽  
Vol 81 (5) ◽  
pp. 501-504 ◽  
Author(s):  
D. C. Sands ◽  
E. J. Ford ◽  
R. V. Miller ◽  
B. K. Sally ◽  
M. K. McCarthy ◽  
...  
Keyword(s):  
Fusarium Oxysporum ◽  
Vascular Tissue ◽  
South American ◽  
Vascular Wilt ◽  
Forma Specialis ◽  
Compatibility Group ◽  
Soil Infestation ◽  
Chamber Studies ◽  
Growth Chamber Studies

A new forma specialis of Fusarium oxysporum (F. oxysporum f. sp. erythroxyli) pathogenic to Erythroxylum coca and E. novogranatense is described. The pathogen was isolated from the vascular tissue of diseased plants from an Erythroxylum plantation in Hawaii. This pathogen causes vascular wilt symptoms and death in both E. coca and E. novogranatense plants as soon as 7 weeks after soil infestation. The pathogenicity of seven isolates from the affected field was determined in field and growth-chamber studies. Genetic variation was not detected among the seven Hawaiian isolates, using arbitrarily primed polymerase chain reaction. The seven isolates could be differentiated from a strain isolated from a diseased E. coca plant from South America. All Hawaiian isolates and the South American isolate belonged to a single vegetative compatibility group.

scholarly journals First Report of Fusarium oxysporum Causing Vascular Wilt of Lamb's Lettuce (Valerianella olitoria) in Italy

Plant Disease ◽  
2004 ◽  
Vol 88 (1) ◽  
pp. 83-83 ◽  
Author(s):  
A. Garibaldi ◽  
G. Gilardi ◽  
M. L. Gullino
Keyword(s):  
Fusarium Oxysporum ◽  
Vascular Tissue ◽  
Selective Medium ◽  
Northern Italy ◽  
Growth Chamber ◽  
Pathogenicity Test ◽  
Vascular Wilt ◽  
First Report ◽  
Forma Specialis ◽  
Vascular Discoloration

Lamb's lettuce (Valerianella olitoria), also known as corn salad, is increasingly grown in Italy and used primarily in the preparation of mixed processed salad. In the summer of 2003, plants of lamb's lettuce cvs. Trophy and Palmares exhibiting wilt symptoms were observed in several commercial greenhouses near Bergamo in northern Italy. Wilted 30-day-old plants were observed first during the month of June, at the time of thinning when temperatures ranged between 28 and 35°C. Disease was generally uniform in the greenhouses and 30 to 50% of the plants were affected. Vascular tissue of affected seedlings appeared red or brown but later turned brown or black. Affected plants were stunted and developed yellowed leaves. Vascular discoloration was continuous from the upper taproot through the crown to the leaf. Fusarium oxysporum was consistently isolated from symptomatic vascular tissue onto a Fusarium-selective medium (1). Seeds of the same cultivars (Trophy and Palmares) affected by the wilt in the field were artificially inoculated by dipping them for 15 min into spore suspensions (1 × 106 conidia per ml) of three isolates of F. oxysporum obtained from infected plants. Noninoculated seeds served as control treatments. Forty seeds per treatment were sown in pots (1-liter volume) containing steam-sterilized soil and maintained at 25°C in a growth chamber programmed for 12 hours of light per day. Wilt symptoms developed on both cultivars 20 days after seeding, and F. oxysporum was consistently reisolated from infected plants. The plants obtained from noninoculated seeds remained healthy. The pathogenicity test was carried out twice with similar results. To our knowledge, this is the first report of F. oxysporum causing vascular wilt of lamb's lettuce and may warrant a new forma specialis designation. Reference: (1) H. Komada. Rev. Plant Prot. Res. 8:114, 1975.

scholarly journals Characterization of Fusarium oxysporum Isolates Obtained from Cucumber in China by Pathogenicity, VCG, and RAPD

Plant Disease ◽  
2004 ◽  
Vol 88 (6) ◽  
pp. 645-649 ◽  
Author(s):  
D. J. Vakalounakis ◽  
Z. Wang ◽  
G. A. Fragkiadakis ◽  
G. N. Skaracis ◽  
D.-B. Li
Keyword(s):  
Fusarium Oxysporum ◽  
Random Amplified Polymorphic Dna ◽  
Vegetative Compatibility ◽  
Stem Rot ◽  
Chinese Isolate ◽  
Vegetative Compatibility Group ◽  
Group I ◽  
Compatibility Group ◽  
First Time

Thirty-four isolates of Fusarium oxysporum, obtained in China from cucumber plants showing either Fusarium wilt (F. oxysporum f. sp. cucumerinum) or root and stem rot (F. oxysporum f. sp. radicis-cucumerinum) symptoms, were characterized by pathogenicity, vegetative compatibility, and random amplified polymorphic DNA (RAPD). Of these, 23 isolates were identified by pathogenicity as F. oxysporum f. sp. cucumerinum, and one as F. oxysporum f. sp. radicis-cucumerinum, while 10 isolates were avirulent on cucumber, melon, sponge gourd, and pumpkin. The Chinese isolates of F. oxysporum f. sp. cucumerinum were assigned to RAPD groups III and XXI and to vegetative compatibility group (VCG) 0183, four new VCGs, 0184 to 0187, and a single-member VCG included in the artificial VCG 018-. The Chinese isolate of F. oxysporum f. sp. radicis-cucumerinum was assigned to RAPD group I and bridging VCG 0260/0261. The occurrence of F. oxysporum f. sp. radicis-cucumerinum on cucumber is reported for the first time in China.

scholarly journals Characterization of a Regional Population of Fusarium oxysporum f. sp. niveum by Race, Cross Pathogenicity, and Vegetative Compatibility

2007 ◽  
Vol 97 (4) ◽  
pp. 461-469 ◽  
Author(s):  
X. G. Zhou ◽  
K. L. Everts
Keyword(s):  
Fusarium Oxysporum ◽  
Vegetative Compatibility ◽  
Infested Soil ◽  
Vegetative Compatibility Group ◽  
Atlantic Region ◽  
Compatibility Group ◽  
Race 1 ◽  
Regional Population ◽  
Race 2

Eighty-eight isolates of Fusarium oxysporum f. sp. niveum, collected from wilted watermelon plants and infested soil in Maryland and Dela-ware, were characterized by cross pathogenicity to muskmelon, race, and vegetative compatibility. Four isolates (4.5%) were moderately pathogenic to ≥2 of 18 muskmelon cultivars in a greenhouse test, and one representative isolate also was slightly pathogenic in field microplots. The four isolates all were designated as race 2, and were in vegetative compatibility group (VCG) 0082. Of the 74 isolates to which a VCG could be assigned, 41 were in VCG 0080, the VCG distributed most widely; 27 were in VCG 0082, and were distributed in half of the 20 watermelon fields surveyed; and 6 were in the newly described VCG 0083, and were restricted to three fields. Among the isolates in VCG 0080, 8 were designated as race 0, 21 as race 1, and 12 as race 2. Of the isolates in VCG 0082, 6 were designated as race 0, 11 as race 1, and 10 as race 2. All isolates in VCG 0083 were designated as race 2. Isolates from more than one race within the same VCG or isolates from more than one VCG were recovered from single plants and fields. No differences in aggressiveness on differential watermelon cultivars were observed among isolates from different VCGs of the same race. A diverse association between virulence and VCG throughout the Mid-Atlantic region suggests that the pathotypes of F. oxysporum f. sp. niveum may be of local origin or at least long existent in the region.

scholarly journals MORPHOLOGICAL, PATHOGENIC AND MOLECULAR CHARACTERIZATION OF Fusarium oxysporum f.sp. ciceri ISOLATES FROM MAHARASHTRA, INDIA

2011 ◽  
Vol 12 (2) ◽  
pp. 47 ◽  
Author(s):  
V.K. Mandhare ◽  
G.P. Deshmukh ◽  
J.V. Patil ◽  
A.A. Kale
Keyword(s):  
Genetic Variability ◽  
Fusarium Oxysporum ◽  
Molecular Characterization ◽  
Pure Culture ◽  
Random Amplified Polymorphic Dna ◽  
Vascular Wilt ◽  
Chick Pea ◽  
Major Factors

Vascular wilt caused by Fusarium oxysporum f.sp. ciceri (FOC) is considered as one of the major factors of low productivity in chickpea. The present study was conducted to determine the morphological, pathogenic and random amplified polymorphic DNA (RAPD) variability of twenty isolates of FOC collected from the Maharashtra State of India, along with four reference isolates corresponding to four known FOC races. Pathogenicity of each isolate was confirmed using the wilt susceptible chick-pea genotype JG-62. The mycelia of all the isolates were septate, hyaline and profusely branched. All the FOC isolates produced micro- and macro-conidia in pure culture within seven days after inoculation. Based on the abilities of the isolates to cause dis-ease on an international set of chickpea differentials and genetic variability estimated by the RAPD technique, these 24 isolates were grouped into two pathotypes, i.e. pathotype I and pathotype II.<br /><br />

scholarly journals Selection and Characterization of the Virulent Fusarium oxysporum f. sp. lycopersici Isolate Inciting Vascular Wilt of Tomato

2018 ◽  
Vol 7 (2) ◽  
pp. 1749-1756
Author(s):  
V. Kavi Sidharthan ◽  
Rashmi Aggarwal ◽  
N. Surenthiran ◽  
G. Pothiraj ◽  
P. Kowsalya ◽  
...  
Keyword(s):  
Fusarium Oxysporum ◽  
Vascular Wilt

Fusarium oxysporum f.sp. elaeidis. [Descriptions of Fungi and Bacteria].

1970 ◽  
Author(s):  
P. Holliday
Keyword(s):  
Fusarium Oxysporum ◽  
Geographical Distribution ◽  
Oil Palm ◽  
Vascular Tissue ◽  
Elaeis Guineensis ◽  
Vascular Wilt ◽  
Soil P ◽  
Acute Form ◽  
Leaf Necrosis ◽  
Internal Necrosis

Abstract A description is provided for Fusarium oxysporum f.sp. elaeidis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Elaeis guineensis. DISEASE: A vascular wilt of the oil palm was first reported from Africa (26: 103; 28: 124). In young palms the first symptom is an extensive chlorosis in some of the central leaves (4th-15th). This is followed by leaf necrosis (giving a flat-topped appearance) and death within a year. In mature palms leaf wilt and necrosis and breaking of the rachis may be rapid, causing death in a few months (acute form). But in the chronic form the progressive dying of the crown inwards may be very slow with new, though smaller, leaves being produced. The vascular tissue in roots and stems becomes orange, darkening progressively to black. It is very characteristic of the disease that the internal necrosis is restricted to the xylem region. Elaeis madagascariensis and E. melanococca have also been found to be affected (37: 52). GEOGRAPHICAL DISTRIBUTION: First found in the Congo, then later in Nigeria (27: 523), Cameroon (40: 148) and Colombia (46, 3389). TRANSMISSION: Presumably through soil.

Molecular characterization of a novel endo-β-1,4-xylanase gene from the vascular wilt fungus Fusarium oxysporum

2001 ◽  
Vol 40 (4) ◽  
pp. 268-275 ◽  
Author(s):  
Esperanza Gómez-Gómez ◽  
Isabel Roncero ◽  
Antonio Di Pietro ◽  
Concepción Hera
Keyword(s):  
Fusarium Oxysporum ◽  
Molecular Characterization ◽  
Vascular Wilt ◽  
Xylanase Gene

scholarly journals Morphological and cultural variability in Fusarium oxysporum f. sp. cubense causing vascular wilt of banana in Kerala

2020 ◽  
Vol 15 (4) ◽  
pp. 344-350
Author(s):  
N. P. Lishma ◽  
K. Anita Cherian
Keyword(s):  
Fusarium Oxysporum ◽  
Aerial Mycelium ◽  
Economic Loss ◽  
Morphological Characters ◽  
Day Length ◽  
Vascular Wilt ◽  
Banana Production ◽  
Preliminary Identification ◽  
Half Strength

Fusarium wilt disease caused by Fusarium oxysporum f. sp. cubense (Foc) is one of the most important diseases that affects the banana production which leads to huge economic loss. Thus, to avoid yield loss and manage the disease on time, morphological and cultural characterization of the pathogen is essential as a preliminary identification step. Thirty isolates were collected from different banana growing regions of Kerala. The isolates were grown on half strength PDA medium. The isolates showed extreme variations in their cultural and morphological characters. Most of the isolates produced white coloured aerial mycelium and few of them were greyish white with white to pink pigmentation. Colony diameter ranged from 59.6 to 90.0 mm at seven days after incubation at 25ºC. The mycelial growth rate varied from 0.83 cm/day to 2.40 cm/day. Length and breadth of macroconidia ranged from 15.01 to 20.20 μm and 2.14 to 5.07 μm whereas, it ranged from 4.49 to 7.42 μm and 1.35 to 3.13 μm for microconidia. The diameter of chlamydospores varied from 5.68 to 9.58 μm. Whereas, the inter septal length and breadth of hyphae varied from 16.14 μm to 22.94 μm and 4.22 μm to 6.57 μm. The cluster analysis based on the quantitative parameters classified the isolates based on variety and genome of the host plants. All the isolates from Rasthali/Poovan (AAB) and Njalipoovan (AB) belonged to the cluster A1 whereas the isolates from Kadali and Chenkadali varieties of banana formed the cluster A2. While, the clustering based on qualitative parameters was irrespective of the variety or genome of the host plant.

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