scholarly journals First Report of Fusarium oxysporum f. sp. radicis-cucumerinum on Cucumber in Spain

Plant Disease ◽  
2001 ◽  
Vol 85 (11) ◽  
pp. 1206-1206 ◽  
Author(s):  
A. Moreno ◽  
A. Alférez ◽  
M. Avilés ◽  
F. Diánez ◽  
R. Blanco ◽  
...  
Keyword(s):  
Fusarium Oxysporum ◽  
Crown Rot ◽  
F1 Hybrid ◽  
Potato Dextrose Broth ◽  
Disease Symptoms ◽  
First Report ◽  
Vascular Discoloration ◽  
Root And Crown Rot ◽  
Three Stages ◽  
Stem Lesions

During December 1999, root and stem rot was observed on greenhouse-grown cucumber (cvs. Albatros, Brunex, Acapulco, and Cerrucho) plants in Almería, Spain, using rock wool cultures. The disease caused severe damage, estimated at a loss of up to 75% of the plants, in the first greenhouse affected; afterward, the disease was found in eight additional greenhouses (14 ha) in 1999 and 2000. Stem lesions extended up to 10 to 12 cm above the crown in mature plants, although no fruit damage was observed. In the advanced stages, abundant development of orange sporodochia was evident on crown and stem lesions, without vascular discoloration. Root, crown, and stem pieces that were placed on potato dextrose agar (PDA) after surface-disinfection with 5% sodium hypochlorite, rinsed, and dried resulted in pure fungal colonies. Based on morphological characteristics of conidia, phialides, and chlamydospores from the isolations, the fungus was identified as Fusarium oxysporum Schlechtend.:Fr. Pathogenicity tests were conducted on cucumber (cvs. Marketmore 76 and Cerrucho [F1 hybrid]), melon (cvs. Amarillo oro, Perlita, Piboule, Tania, and Nipper [F1]), watermelon (cvs. Sugar Baby, Sweet Marvel, Jubilee, and Pata Negra and hybrid Crimson sweet), Cucurbita maxima × Cucurbita moschata, zucchini (cv. Senator), and loofah (Luffa aegyptiaca) at several stages: (i) pregermination; (ii) 1 or 2 true leaves; and (iii) more than 10 true leaves. Five fungal isolates were grown on PDA or shaken potato dextrose broth at 25°C for 8 days. Inoculation was performed in pots (10 seeds or plants of each cultivar or hybrid and isolate) by drenching with 100 ml of a fungal suspension (104 to 106 CFU/ml). Sterile water was applied to noninoculated control plants. Tests were repeated in growth chambers at 25°C (night) and 28°C (day) with a 16-h photoperiod. Fifteen to fifty days after inoculation, cucumber and melon plants at all three stages developed symptoms of root and crown rot in 100% of inoculated plants, with no observed vascular discoloration. Fifty days after inoculation, all three stages of C. maxima × C. moschata and zucchini remained symptomless. Loofah and watermelon germinated poorly or not at all when inoculated at the pregermination stage. Fifteen to fifty days after inoculation, 100% of inoculated cucumber and melon plants developed symptoms. Watermelon plants inoculated at the 10 or more true-leaf stage did not develop disease symptoms. No symptoms developed on noninoculated control plants. F. oxysporum was reisolated from infected roots, crowns, and stems of inoculated plants, confirming Koch's postulates. The main symptoms on cucumber infected by F. oxysporum f. sp. cucumerinum are wilt, yellowing, and vascular discoloration. In contrast, based on inoculation of the host differentials and the resulting disease symptoms found in this study, the fungus was identified as F. oxysporum f. sp. radicis-cucumerinum (1). To our knowledge, this is the first report of F. oxysporum f. sp. radicis-cucumerinum causing root and crown rot in cucumber in Spain. Reference: (1) D. J. Vakalounakis. Plant Dis. 80:313, 1996.

scholarly journals First Report of Fusarium oxysporum Causing Root and Crown Rot on Barbados Aloe in Greece

Plant Disease ◽  
2015 ◽  
Vol 99 (11) ◽  
pp. 1649-1649 ◽  
Author(s):  
D. J. Vakalounakis ◽  
N. Kavroulakis ◽  
K. Lamprou
Keyword(s):  
Fusarium Oxysporum ◽  
Crown Rot ◽  
First Report ◽  
Root And Crown Rot

scholarly journals First Report of Root and Crown Rot Caused by Fusarium oxysporum on Sweet Cherry (Prunus avium) in British Columbia

Plant Disease ◽  
2016 ◽  
Vol 100 (4) ◽  
pp. 855 ◽  
Author(s):  
J. R. Úrbez-Torres ◽  
J. Boulé ◽  
P. Haag ◽  
C. Hampson ◽  
D. T. O’Gorman
Keyword(s):  
British Columbia ◽  
Fusarium Oxysporum ◽  
Sweet Cherry ◽  
Prunus Avium ◽  
Crown Rot ◽  
First Report ◽  
Root And Crown Rot

scholarly journals First Report of Fusarium oxysporum f. sp. lycopersici Race 3 and F. oxysporum f. sp. radicis-lycopersici in Tomatoes in the Azapa Valley of Chile

Plant Disease ◽  
2014 ◽  
Vol 98 (10) ◽  
pp. 1432-1432 ◽  
Author(s):  
G. Sepúlveda-Chavera ◽  
W. Huanca ◽  
R. Salvatierra-Martínez ◽  
B. A. Latorre
Keyword(s):  
Fusarium Oxysporum ◽  
Tap Water ◽  
Universal Primers ◽  
Conidial Suspension ◽  
Laboratory Manual ◽  
First Report ◽  
Solanum Lycopersicum L ◽  
Vascular Discoloration ◽  
Seedling Roots ◽  
Pcr Assays

Tomato (Solanum lycopersicum L.) is an important crop in the Azapa Valley (18°35′ S, 69°30′ W) in northern Chile, with approximately 600 ha of fresh tomatoes under greenhouses. Cultivars resistant to Fusarium oxysporum f. sp. lycopersici (FOL) races 1 and 2 are mainly used. However, in 2012 and 2013, Fusarium wilt incidence was 2 to 3%. Symptoms appeared unilaterally and consisted of yellowing, leaf wilting of lower leaves, dark brown vascular discoloration, and plant death. The aim of this study was to determine the causal agent of tomato wilt in seven tomato greenhouses in the Azapa Valley. Stem samples (5 × 5 mm) were obtained 10 cm of the stem base from wilted tomatoes ‘Naomi’ (BIOAMERICA S.A., Chile) or from Maxifort tomato rootstock (De Ruiter Seed, USA), both FOL resistant to races 1 and 2. Samples were washed with tap water, surface sterilized with 1% NaClO for 3 min, and incubated on sterile moist paper towels in petri plates for 5 days at 22°C. Mycelial fragments from white colonies, emerging from diseased tissues, were transferred to PDA. Six Fusarium isolates were characterized by the presence of hyaline macroconidia, mostly 3 to 5 septate, slightly curved (19.2 to 32.1 × 2.9 to 4.5 μm) and single-celled, oval to elongated microconidia (3.1 to 8.9 × 2.0 to 4.0 μm). Chlamydospores were single or in pairs. These isolates were identified as F. oxysporum (3). The identity of F. oxysporum was confirmed by PCR assays using genomic DNA of each isolated and the universal primers Uni F and Uni R that generate a 672-bp PCR product. The pathogenic form and races were determined by PCR assays using the specific primers uni, sp13, sp23, and sprl that were able to discriminate all the three FOL races as well as F. oxysporum f. sp. radicis-lycopersici (FORL) isolates (2). The sp13 and sp23 primers amplified DNA bands of 445 and 518 bp, confirming the identity of FOL race 3. However, sprl amplified a fragment of 947 bp corresponding to FORL (2). Pathogenicity tests were conducted on 25-day-old seedlings (10 seedlings per isolate) of tomato ‘Poncho Negro,’ which is susceptible to FOL and FORL. Seedling roots were cut, submerged for 5 min in conidial suspension of 2 × 106 conidia/ml, and transplanted to 250-ml plastic containers with sterile substrate (sand/peat, 1:1). Equally treated non-inoculated seedlings were left as controls. The first symptoms induced by each of the five FOL isolates appeared 8 days after incubation under greenhouse and were characterized by yellowing of older leaves, sometimes affecting one side of the plant, vascular discoloration of the stem, and eventually plant death. In contrast, all seedlings inoculated with a FORL isolate developed a necrotic lesion and vascular discoloration at the base of the stems near the soil line, followed by wilting and plant death. Control plants remained asymptomatic. F. oxysporum was re-isolated only from inoculated plants, completing Koch's postulates. FOL and FORL were reported earlier in other tomato growing areas of Chile (1), located over 1,000 km south of the Azapa Valley. However, this is the first report of FOL race 3 and FORL in the Azapa Valley and FOL race 3 is reported for the first time in Chile. References: (1) S. Acuña. Compendio de Fitopatógenos de Cultivos Agrícolas. Servicio Agrícola y Ganadero. Gobierno de Chile, 2008. (2) Y. Hirano and T. Arie. J. Gen. Plant Pathol. 72:273, 2006. (3) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell Publishing, Ames, IA, 2006.

scholarly journals First Report of Phoma exigua as a Pathogen of Salal (Gaultheria shallon) in British Columbia, Canada

Plant Disease ◽  
2005 ◽  
Vol 89 (6) ◽  
pp. 685-685 ◽  
Author(s):  
S. F. Shamoun ◽  
S. Zhao
Keyword(s):  
British Columbia ◽  
The United States ◽  
Gaultheria Shallon ◽  
Centraalbureau Voor ◽  
Potato Dextrose Broth ◽  
Voucher Specimen ◽  
Disease Symptoms ◽  
Phoma Exigua ◽  
First Report ◽  
Plastic Bags

Salal (Gaultheria shallon Pursh.) is an ericaceous, evergreen, and rhizomatous shrub that competes for nutrients and moisture with young conifers in low elevation, coastal British Columbia (BC). A survey was conducted on southern Vancouver Island, BC during the summer of 1999 to find fungal pathogens of salal that might serve as biocontrol organisms (3). Phoma exigua Desmaz. (isolate PFC2705) near Parksville, BC proved to be pathogenic on salal. Identification of PFC2705 at the Centraalbureau voor Schimmelcultures was based on morphology and ITS sequences (GenBank Accession No. AY927784). Pathogenicity was determined with 24 salal seedlings (3-month-old) by inoculating with mycelial suspensions (20% v/v) or conidial suspensions (1 × 106 conidia per ml in 0.5% potato dextrose broth). Inoculated seedlings were placed in plastic bags and incubated in a greenhouse (16 to 23°C with natural light). Plastic bags were removed after 2 days. Initial disease symptoms were observed 2 days after inoculation. Brown, sunken lesions appeared on the surface of young leaves and stems and extended quickly. All seedlings were killed within 14 days. Twelve control plants showed no disease symptoms. With diseased salal leaves incubated at 23°C with 12-h fluorescent light/dark and 100% relative humidity, pycnidia appeared on leaf surfaces within 5 days. Conidia were hyaline, ellipsoid, one-celled, sometimes two- to three-celled, 2.5 to 3.8 × 5 to 12.5 μm, with a rounded base; the colony was gray or dark gray on potato dextrose agar after 5 to 7 days. Reisolation from the inoculated diseased leaves produced a mycelial colony that shared the same growth and morphological characteristics as the initial isolate. Phyllosticta gaultheriae Ellis & Everh., a widely reported foliar pathogen of salal, is distinct morphologically from P. exigua (1). To our knowledge, this is the first report of P. exigua as a pathogen of salal in Canada (2). A voucher specimen has been deposited at the Pacific Forestry Center Herbarium (DAVFP No. 28735). References: (1) J. Bissett and S. J. Darbyshire. No. 275 in: Fungi Canadenses, 1984. (2) D. F. Farr et al. Fungi on Plants and Plant Products in the United States. The American Phytopathological Society. St. Paul. MN, 1989. (3) S. F. Shamoun et al. Can. J. Plant Pathol. 22:192, 2000.

scholarly journals First Report of Neopestalotiopsis clavispora Causing Root and Crown Rot on Strawberry in Italy

Plant Disease ◽  
2019 ◽  
Vol 103 (11) ◽  
pp. 2959-2959 ◽  
Author(s):  
G. Gilardi ◽  
F. Bergeretti ◽  
M. L. Gullino ◽  
A. Garibaldi
Keyword(s):  
Crown Rot ◽  
First Report ◽  
Root And Crown Rot

scholarly journals Fusarium Root and Crown Rot: A Disease of Container-Grown Hostas

Plant Disease ◽  
2000 ◽  
Vol 84 (9) ◽  
pp. 980-988 ◽  
Author(s):  
B. Wang ◽  
S. N. Jeffers
Keyword(s):  
South Carolina ◽  
Crown Rot ◽  
Undescribed Species ◽  
Fresh Weight ◽  
Fusarium Spp ◽  
Disease Symptoms ◽  
Leaf Yellowing ◽  
Oat Seeds ◽  
Root And Crown Rot ◽  
Fusarium Sp

A previously unreported disease was observed on 11 cultivars of container-grown hosta plants at five wholesale nurseries in South Carolina between 1997 and 1999. Symptoms included leaf yellowing, plant stunting, rotting of and vascular discoloration in roots, and necrosis in the crowns. Fusarium spp. consistently were isolated from symptomatic hosta plants. Four species were recovered: F. solani, F. oxysporum, F. proliferatum, and an undescribed species designated Fusarium sp.; F. solani and Fusarium sp. were recovered most frequently. To demonstrate pathogenicity, four methods were used to inoculate hosta plants with representative isolates of F. solani, F. oxysporum, and Fusarium sp. Two types of inoculum, colonized oat seeds and conidium suspensions, were used to inoculate wounded and nonwounded plants. Disease symptoms occurred consistently only on hosta plants inoculated by dipping wounded roots and crowns into suspensions of conidia. Symptoms were most severe on plants inoculated with Fusarium sp. and much less severe on plants inoculated with F. solani or F. oxysporum. Disease severity increased and fresh weight of inoculated plants decreased when the concentration of inoculum of Fusarium sp. was increased over the range of 1 × 103 to 1 × 107 conidia per ml. Isolates of Fusarium sp., F. solani, and F. oxysporum varied in virulence when Hosta ‘Francee’ plants were inoculated. This study demonstrated that Fusarium root and crown rot of container-grown hostas is caused primarily by Fusarium sp. but that it also can be caused by F. solani and F. oxysporum. Fusarium sp. appears to be taxonomically distinct from other species, and its identity currently is under investigation.

scholarly journals First Report of Fusarium Wilt of Canary Island Date Palm Caused by Fusarium oxysporum f. sp. canariensis in Louisiana

Plant Disease ◽  
2011 ◽  
Vol 95 (9) ◽  
pp. 1192-1192 ◽  
Author(s):  
R. Singh ◽  
A. Castro ◽  
D. M. Ferrin ◽  
R. S. Harris ◽  
B. Olson
Keyword(s):  
South Carolina ◽  
Fusarium Oxysporum ◽  
New Orleans ◽  
Fusarium Wilt ◽  
Canary Island ◽  
Date Palm ◽  
Distilled Water ◽  
Date Palms ◽  
First Report ◽  
Vascular Discoloration

Canary Island date palm (Phoenix canariensis Hort. Ex Chabaud) is a signature palm planted in New Orleans, LA. Currently, the city has approximately 1,000 mature Canary Island date palms. During the fall of 2009, 153 palms were inspected with 27 palms exhibiting typical symptoms of Fusarium wilt. Symptoms included one-sided death and a reddish brown streak on the rachis of affected fronds and death of the leaflets. Longitudinal sections of affected fronds showed vascular discoloration. Severely infected palms were completely dead. Small pieces of diseased tissue from five palms were surface sterilized with sodium hypochlorite (0.6%) for 2 to 3 min, then rinsed in sterile distilled water, blotted dry, and plated on potato dextrose agar (PDA). Fungal colonies on PDA produced a purple pigment, and both macro- and microconidia that are typical of Fusarium oxysporum were observed under a light microscope. A single-spore culture of isolate PDC-4701 was obtained. DNA from this isolate was extracted with a DNeasy Plant Mini kit (Qiagen Inc., Valencia, CA) and primers ef1 and ef2 were used to amplify and sequence the translation elongation factor 1-α gene (2). NCBI BLAST analysis of the 616-bp sequence resulted in 100% identity with F. oxysporum f. sp. canariensis isolates PLM-385B from Texas and PLM-511A from South Carolina (GenBank Accession Nos. HM 591538 and HM 591537, respectively). Isolate PDC-4701, grown on PDA for 2 weeks, was used to inoculate 10 9-month-old P. canariensis seedlings. An 18-gauge needle was used to inject 15 ml of a 107 conidia/ml suspension into the stem near the soil line. Each seedling was inoculated at two locations and covered with Parafilm at the inoculation sites. Ten control seedlings were injected with sterile distilled water in the same manner. Inoculated and control seedlings were maintained in a greenhouse at 28 ± 2°C. Leaves of all 10 inoculated seedlings started to wilt 3 months after inoculation. Internal vascular discoloration was observed and the pathogen was reisolated from the symptomatic seedlings. No symptoms developed on any of the 10 control seedlings. On the basis of morphology and DNA sequence data, this pathogen is identified as F. oxysporum f. sp. canariensis. Fusarium wilt of Canary Island date palm has been previously reported from California, Florida, Nevada, Texas, and South Carolina (1). To our knowledge, this is the first report of Fusarium wilt of Canary Island date palm caused by F. oxysporum f. sp. canariensis in Louisiana, extending its geographic range. The disease may adversely affect the tradition of planting Canary Island date palms in New Orleans. The sequence of isolate PDC-4701 has been submitted to the NCBI database (GenBank Accession No. JF826442) and a culture specimen has been deposited in the Fusarium Research Center culture collection (Accession No. O-2602) at the Pennsylvania State University, University Park, PA. References: (1) M. L. Elliott et al. Plant Dis. 95:356, 2011. (2) D. M. Geiser et al. Eur. J. Plant Pathol. 110:473, 2004.

scholarly journals First Report of Phytophthora citrophthora on Penstemon barbatus in Italy

Plant Disease ◽  
2006 ◽  
Vol 90 (9) ◽  
pp. 1260-1260 ◽  
Author(s):  
A. Garibaldi ◽  
D. Bertetti ◽  
D. Minerdi ◽  
M. L. Gullino
Keyword(s):  
Its Region ◽  
The United States ◽  
Phytophthora Species ◽  
Crown Rot ◽  
Pathogenicity Test ◽  
Phytophthora Citrophthora ◽  
First Report ◽  
Blastn Analysis ◽  
Root And Crown Rot ◽  
Pathogenicity Tests

Penstemon barbatus (Cav.) Roth (synonym Chelone barbata), used in parks and gardens and sometimes grown in pots, is a plant belonging to the Scrophulariaceae family. During the summers of 2004 and 2005, symptoms of a root rot were observed in some private gardens located in Biella Province (northern Italy). The first symptoms resulted in stunting, leaf discoloration followed by wilt, root and crown rot, and eventually, plant death. The diseased tissue was disinfested for 1 min in 1% NaOCl and plated on a semiselective medium for Oomycetes (4). The microorganism consistently isolated from infected tissues, grown on V8 agar at 22°C, produced hyphae with a diameter ranging from 4.7 to 5.2 μm. Sporangia were papillate, hyaline, measuring 43.3 to 54.4 × 26.7 to 27.7 μm (average 47.8 × 27.4 μm). The papilla measured from 8.8 to 10.9 μm. These characteristics were indicative of a Phytophthora species. The ITS region (internal transcribed spacer) of rDNA was amplified using primers ITS4/ITS6 (3) and sequenced. BLASTn analysis (1) of the 800 bp obtained showed a 100% homology with Phytophthora citrophthora (R. & E. Sm.) Leonian. The nucleotide sequence has been assigned GenBank Accession No. DQ384611. For pathogenicity tests, the inoculum of P. citrophthora was prepared by growing the pathogen on autoclaved wheat and hemp kernels (2:1) at 25°C for 20 days. Healthy plants of P. barbatus cv. Nano Rondo, 6 months old, were grown in 3-liter pots (one plant per pot) using a steam disinfested substrate (peat/pomix/pine bark/clay 5:2:2:1) in which 200 g of kernels per liter of substrate were mixed. Noninoculated plants served as control treatments. Three replicates were used. Plants were maintained at 15 to 20°C in a glasshouse. The first symptoms, similar to those observed in the gardens, developed 21 days after inoculation, and P. citrophthora was consistently reisolated from infected plants. Noninoculated plants remained healthy. The pathogenicity test was carried out twice with similar results. A nonspecified root and crown rot of Penstemon spp. has been reported in the United States. (2). To our knowledge, this is the first report of P. citrophthora on P. barbatus in Italy as well as in Europe. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997 (2) F. E. Brooks and D. M. Ferrin. Plant Dis. 79:212, 1995. (3) D. E. L. Cooke and J. M. Duncan. Mycol. Res. 101:667, 1997. (4) H. Masago et al. Phytopathology 67:425, 1977.

scholarly journals First Report of Stem Blight Caused by Botrytis cinerea on Jasminum officinalis in Italy

Plant Disease ◽  
2008 ◽  
Vol 92 (12) ◽  
pp. 1708-1708
Author(s):  
D. Aiello ◽  
G. Parlavecchio ◽  
A. Vitale ◽  
G. Polizzi
Keyword(s):  
Botrytis Cinerea ◽  
Far East ◽  
Weather Conditions ◽  
Economic Loss ◽  
Transparent Plastic ◽  
Disease Symptoms ◽  
First Report ◽  
Stem Blight ◽  
Plastic Bags ◽  
Stem Lesions

Common jasmine (Jasminum officinalis L.) is an evergreen shrub that is native to the Middle and Far East. It is widely grown in Europe as an ornamental plant and in southeastern France for fragrance for the perfume industry. In March of 2008, a previously undescribed disease was observed on potted (6-month- to 3-year-old) common jasmine plants growing in open fields in a nursery of eastern Sicily, Italy. More than 20% of the plants showed disease symptoms. Diseased plants had small to large, brown or black lesions on stem. The lesions expanded rapidly, girdled the stem and caused blight of entire branches, and occasionally killed the plant. Abundant conidia and mycelia were detected on the surface of dead and dying stems under cool and humid conditions, which resulted in a moldy gray appearance. Botrytis cinerea Pers.:Fr. (1) was consistently isolated from affected tissues disinfected for 1 min in 1% NaOCl, rinsed in sterile water, and plated on potato dextrose agar (PDA). Colonies were at first white then became gray after 6 to 7 days when spores differentiated. White sclerotia developed after 8 to 9 days and turned black with age. Size of the conidia produced on 1-month-old culture ranged from 5.0 to 9.5 × 6.5 to 12.5 μm on the basis of 50 spore measurements. Sclerotia were spherical or irregular and ranged from 1.0 to 2.5 × 0.9 to 2.9 mm (average 1.7 × 1.8 mm). Stems of eight 6-month-old common jasmine plants were lightly wounded with a sterile razor and inoculated with 3-mm-diameter plugs of PDA from 10-day-old mycelial cultures, eight similar plants were inoculated with mycelium without wounding, and an equal number of noninoculated plants inoculated with only PDA plugs served as control. After inoculation, plants were enclosed in transparent plastic bags at 20 ± 2°C for 5 days. Stem lesions identical to the ones observed in the nursery were detected on all wounded and on two nonwounded fungus-inoculated plants within 5 to 7 days. Control plants remained healthy. B. cinerea was reisolated from typical lesions. The unusually cool and humid weather conditions recorded in Sicily are supposed to be highly conducive of disease outbreak. Although B. cinerea does not usually kill the plants, under these environmental conditions this disease can cause significant economic loss to ornamental nurseries. To our knowledge, this is the first report of B. cinerea causing stem blight on J. officinalis. Reference: (1) M. B. Ellis. Dematiaceous Hyphomycetes. CAB, Kew, Surrey, England, 1971.

scholarly journals First Report of Fusarium Wilt of Cilantro Caused by Fusarium oxysporum in California

Plant Disease ◽  
2005 ◽  
Vol 89 (10) ◽  
pp. 1130-1130 ◽  
Author(s):  
S. T. Koike ◽  
T. R. Gordon
Keyword(s):  
Fusarium Oxysporum ◽  
Fusarium Wilt ◽  
Vascular Tissue ◽  
Fusarium Species ◽  
Wilt Disease ◽  
Apium Graveolens ◽  
Peat Moss ◽  
State University ◽  
First Report ◽  
Vascular Discoloration

Cilantro, or coriander (Coriandrum sativum), is a leafy vegetable in the Apiaceae and is grown commercially in California primarily for use as a fresh herb. During 2002 and 2003 in coastal California (Santa Barbara County), commercial cilantro fields showed symptoms of a wilt disease. Affected plants grew poorly and were stunted. Lower foliage turned yellow with reddish tinges, and plants wilted during warmer times of the day. The main stem, crown, and taproot exhibited vascular discoloration that was reddish to light brown. As disease progressed, plants eventually died. For both years, the disease distribution was limited to isolated small patches (each patch measuring less than 1 m2 in area). A fungus was consistently isolated from symptomatic vascular tissue in crowns and taproots. On the basis of colony and conidial morphology, the isolates were identified as Fusarium oxysporum (2). No other fungi or bacteria were recovered from these plants. To test pathogenicity, suspensions containing 1 × 106 conidia/ml were prepared for five isolates. The roots of 30-day-old cilantro plants of four cultivars (30 plants each of Festival, Leisure, Santo, and LSO 14) were clipped and then soaked in the suspensions for 20 min. The roots of 30 plants of each cultivar were soaked in water as a control. Plants were repotted into new redwood bark + peat moss rooting medium and maintained in a greenhouse setting at 24 to 26°C. After 1 month, 95% or more of the inoculated plants showed yellowing and vascular discoloration symptoms similar to those seen in the field. F. oxysporum was reisolated from all inoculated plants. The four cilantro cultivars did not show differences in disease severity. Control plants showed no symptoms, and the fungus was not recovered from these plants. The experiment was repeated and the results were the same. Experiments also were conducted to determine if cilantro isolates could cause disease in celery (Apium graveolens var. dulce). Celery transplants and cilantro seedlings were prepared and inoculated as described above. However, after 2 months, celery plants did not show any disease symptoms, while the cilantro developed wilt symptoms and eventually died. A Fusarium wilt disease has been reported on coriander in Argentina and India where the pathogen was named F. oxysporum f. sp. coriandrii (1,3). To our knowledge, this is the first report of Fusarium wilt of cilantro in California. References: (1) M. Madia et al. Fitopatologia 34:155, 1999. (2) P. E. Nelson et al. Fusarium species: An Illustrated Manual for Identification. Pennsylvania State University Press, University Park, 1983. (3) U. S. Srivastava. Indian Phytopathol. 22:406, 1969.

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