First Report of Artichoke Downy Mildew Caused by Bremia lactucae in Argentina

In 1999, downy mildew was detected on artichoke (Cynara scolymus L.) plants from La Plata, Buenos Aires Province. The disease was observed on various commercial varieties. Symptoms were angular interveinal chlorotic spots less than 3 cm in size. These infected areas, although not confluent, covered a wide surface and caused early death of the leaves. On the undersides of these lesions, white-grayish sporulation was abundant, consisting of sporangiophores with dichotomous branches, widened in their peaks with 2 to 7 terminal sterigmata. Sporangia were ellipsoidal, hyaline and 14 to 30 × 12 to 25 μm in size. Oospores were not observed in leaf tissues. The pathogen was identified as Bremia lactucae Regel (1). Pathogenicity was confirmed with the inoculation of healthy artichoke plants. They were incubated in a humidity chamber at 10 to 15°C, and after 16 days chlorotic spots and downy mildew colonies developed. The presence of B. lactucae was confirmed by macro- and microscopic observation and Koch's postulates were fulfilled. This is the first report of downy mildew on artichoke in Argentina. Because it is widespread in the most important artichoke-growing area in Argentina (2), downy mildew should be considered in the cultural and sanitary management of the crop. References: (1) P. Corda. Hypermedia Prot. Plantes, INRA, 1995. (2) A. Ricceti et al. Bol. Hortic. 4:4, 1996.

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New host and distribution expansion for Pterygodermatites (Multipectines) affinis

Helminthologia ◽

10.1515/helmin-2015-0076 ◽

2016 ◽

Vol 53 (1) ◽

pp. 81-86 ◽

Cited By ~ 1

Author(s):

N. P. Scioscia ◽

P. M. Beldomenico ◽

G. M. Denegri

Keyword(s):

Buenos Aires ◽

Buenos Aires Province ◽

New Host ◽

Fecal Samples ◽

First Report ◽

First Case ◽

Small Intestines

SummaryThe present study reports the first case of infection by Pterygodermatites affinis in Lycalopex gymnocercus, and the first report of this nematode in Argentina. Examining 80 foxes from Buenos Aires province, specimens of this species were recovered from 21.25 % of the small intestines and eggs were found in 7.5 % of the fecal samples.

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First Report of Bremia lactucae Causing Downy Mildew on Helichrysum bracteatum in Italy

Plant Disease ◽

10.1094/pdis.2003.87.3.315a ◽

2003 ◽

Vol 87 (3) ◽

pp. 315-315 ◽

Cited By ~ 1

Author(s):

A. Garibaldi ◽

A. Minuto ◽

G. Gilardi ◽

M. L. Gullino

Keyword(s):

Downy Mildew ◽

Morphological Characteristics ◽

The United States ◽

Northern Italy ◽

Plant Diseases ◽

Bremia Lactucae ◽

First Report ◽

Parasitic Fungi ◽

Commercial Farms ◽

Helichrysum Bracteatum

Helichrysum bracteatum, also known as strawflower, is commonly grown for the production of dried flowers and, more recently, as a potted plant. This latter cultivation system is becoming increasingly important on the Liguria Coast in northern Italy. During the spring of 2002, severe oubreaks of a previously unknown disease were observed in commercial farms in the area of Albenga (northern Italy) on several cultivars of H. bracteatum. Leaves of infected plants appeared curled and blistered; the infected portions of leaves turned chlorotic. On the lower leaf surface of chlorotic areas, a dense, whitish growth was evident. Infected leaves eventually wilted without dropping. Basal leaves with poor air circulation were the most severely affected. Certain cultivars of H. bracteatum (such as ‘Florabella Pink’) were most seriously affected, while others (‘Florabella Gold’ and ‘Florabella White’) had less disease. Microscopic observations revealed sporangiophores emerging from the stomata that were dichotomically branched, ending with 4 to 7 sterigmata. The sporangia were globose and measured 15.5 to 16.8 μm in diameter. The pathogen was identified as Bremia lactucae based on the morphological characteristics. Pathogenicity was confirmed by inoculating healthy H. bracteatum (100-day-old ‘Florabella Gold’) as well as Lactuca sativa (25-day-old ‘Salad bowl’) plants with a sporangial suspension (1 × 105 sporangia/ml). Five plants of H. bracteatum and 10 of lettuce were used as replicates. Noninoculated plants served as controls. Inoculated and uninoculated plants were maintained in a growth chamber at 20°C and 90 to 95% relative humidity. After 7 to 10 days, typical symptoms of downy mildew developed on H. bracteatum and lettuce plants artificially inoculated. Bremia lactucae was observed on infected leaves. Uninoculated plants did not show symptoms. To our knowledge, this is the first report of Bremia lactucae on H. bracteatum in Italy. B lactucae was previously reported as the causal agent of downy mildew on H. bracteatum in several countries including the United Kingdom (3), the United States (1), and Egypt (2). References: (1) S. A. Alfieri et al. Index of plant diseases in Florida. Bull No. 11, 1984. (2) H. Elarosi and M. W. Assawah. Rev. Plant Prot. Res., 39:583, 1959. (3) W. C. Moore. British Parasitic Fungi. Cambridge University Press, Cambridge, 1959.

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First Report of Downy Mildew Caused by Pseudoperonospora cubensis on Chayote (Sechium edule) in Taiwan

Plant Disease ◽

10.1094/pdis-92-12-1706c ◽

2008 ◽

Vol 92 (12) ◽

pp. 1706-1706 ◽

Cited By ~ 11

Author(s):

Y. Ko ◽

C. Y. Chen ◽

C. W. Liu ◽

S. S. Chen ◽

S. Maruthasalam ◽

...

Keyword(s):

Downy Mildew ◽

Plant Diseases ◽

Pseudoperonospora Cubensis ◽

First Report ◽

Agricultural Improvement ◽

Republic Of China ◽

Sechium Edule ◽

Leaf Surfaces ◽

Leaf Tissues ◽

The Republic

Chayote (Sechium edule) is cultivated on more than 500 ha in Taiwan for its edible shoots and fruit. In August 2005 and later, 40 to 75% of the chayote plants cultivated in the Taichung District Agricultural Improvement Station in Puli developed pale yellow, irregular spots on the upper leaf surfaces with corresponding sporulation on the lower leaf surfaces. The lesions eventually became necrotic and spread over the entire leaf surface, leading to defoliation. Pseudoperonospora cubensis, which was previously reported as the cause of downy mildew on squash (Cucurbita moschata), muskmelon (Cucumis melo), cucumber (Cucumis sativus), and sponge gourd (Luffa cylindrica) in Taiwan, was identified (1). Sporangiophores were 182 to 410 μm long, 4.8 to 7.2 μm wide, and dichotomously branched. Sporangia were grayish, ovoid to ellipsoidal, 18.2 to 38.6 μm long, and 13.5 to 25.2 μm wide. Biflagellate zoospores were 9.5 to 12.6 μm in diameter. Pathogenicity tests were conducted four times with six 2-week-old plants in each trial. A sporangial suspension (1 × 105 spores per ml) prepared from infected leaves (5 to 6 weeks after infection) was sprayed on all leaves until runoff. The plants were then covered with polythene bags and incubated for 48 h at 18 ± 1°C in a growth chamber. Control plants were sprayed with sterile water. Characteristic symptoms developed on all inoculated plants after 20 days, while control plants remained symptomless. Microscopic observation of leaf tissues of symptomatic plants confirmed the presence of P. cubensis. To our knowledge, this is the first report of P. cubensis causing downy mildew on chayote in Taiwan. References: (1) S. T. Hsu et al. List of Plant Diseases in Taiwan. The Phytopathological Society of the Republic of China, 2002.

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Acute and chronic nervous signs in cattle associated with Phalaris angusta poisoning in Argentina

Pesquisa Veterinária Brasileira ◽

10.1590/s0100-736x2010000100010 ◽

2010 ◽

Vol 30 (1) ◽

pp. 63-66 ◽

Cited By ~ 3

Author(s):

Germán Cantón ◽

Carlos Campero ◽

Matías Villa ◽

Ernesto Odriozola

Keyword(s):

Axonal Degeneration ◽

Buenos Aires ◽

Clinical Findings ◽

Buenos Aires Province ◽

South American ◽

First Report ◽

Natural Grass ◽

Pigment Deposition ◽

Affected Calf ◽

Clinical Cases

Phalaris angusta is a South American natural grass that produces poisoning in sheep and cattle in Argentina and Brazil. Phalaris spp. can produce unrelated forms of poisoning in ruminants, acute and chronic syndromes. The objective of this paper was to describe an outbreak of acute and chronic Phalaris nervous syndrome in 53 of 980 fattening steers and heifers in a farm of Buenos Aires province. On September of 2006 the animals developed nervous signs and died after 3-5 days. The herd was removed to a phalarisfree pasture. Three months later (on December) 15 new clinical cases developed in the herd. Necropsy performed in one affected calf showed neither grossly nor microscopic changes. Microscopically, there were no major alterations in tissues. Nervous signs had been described in some field cases where neither pigment deposition nor axonal degeneration could be detected. Clinical findings displayed by affected cattle after consumption of Phalaris angusta pastures resemble those observed by other authors in Phalaris staggers. This is the first report in Argentina where both syndromes were seen in the same herd.

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First Report of Downy Mildew Caused by a Peronospora Species on Sweet Basil (Ocimum basilicum) in Massachusetts

Plant Disease ◽

10.1094/pdis-93-3-0318b ◽

2009 ◽

Vol 93 (3) ◽

pp. 318-318 ◽

Cited By ~ 7

Author(s):

R. L. Wick ◽

N. J. Brazee

Keyword(s):

South Africa ◽

Downy Mildew ◽

Pcr Amplification ◽

Infected Leaf ◽

Its2 Region ◽

Academic Press ◽

First Report ◽

Sweet Basil ◽

Foliar Blight ◽

Leaf Tissues

In September of 2008, downy mildew was discovered to be causing a serious foliar blight of sweet basil at several farms and greenhouses in Massachusetts. Infected leaves had chlorotic vein-bounded patches and diffuse chlorosis, and a characteristic gray, fuzzy growth was on the abaxial surface. Microscopic observations revealed branched sporangiophores that measured 187.5 to 325 μm (average 285 μm) long. Sporangia measured 22.5 to 30 × 20 to 22.5 μm (average 26.7 × 20.9 μm). No oospores were found. Sporangium measurements are comparable to unnamed Peronospora species reported previously on basil from Italy, Switzerland, and South Africa (1,2). Sequence analyses were conducted on five isolates of ‘Nufar’ basil by extracting DNA from a sporangial suspension washed from leaves and infected leaf tissues using the Qiagen DNeasy plant tissue kit (Qiagen, Valencia, CA). PCR amplification of the ITS1, 5.8S, and ITS2 region was performed using primers ITS6 and ITS4 (3). The sequences of the five isolates were identical. BLAST analyses of the sequences revealed a 99% similarity to the unnamed Peronospora species on sweet basil in Europe and South Africa (1,2). To our knowledge, this is the first report of a Peronospora species on sweet basil in Massachusetts. References: (1) L. Belbahri et al. Mycol. Res. 109:1276, 2005. (2) A. McLeod et al. Plant Dis. 90:1115, 2006. (3) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.

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First Report of Foliar Infection of Cabbage by Phytophthora drechsleri in Argentina

Plant Disease ◽

10.1094/pdis-04-12-0342-pdn ◽

2012 ◽

Vol 96 (12) ◽

pp. 1830-1830

Author(s):

M. J. Iribarren ◽

B. A. González ◽

M. L. Velez ◽

A. Greslebin ◽

M. Steciow

Keyword(s):

Buenos Aires ◽

Tap Water ◽

Its Region ◽

Buenos Aires Province ◽

Data Set ◽

First Report ◽

Morphological Studies ◽

Mycelial Plug ◽

Phytophthora Drechsleri ◽

Maximum Temperatures

Cabbage (Brassica oleracea var. capitata L.) is a popular crop grown along the northeast horticultural belt of Buenos Aires Province, Argentina. In the summer of 2010, fields in this region remained flooded for long periods due to frequent and intense precipitation (560 mm from January to March). Commercial cabbage crops in the cities of Luján and General Rodríguez developed patches of diseased plants that were stunted and wilted. Affected plants had necrotic areas in the crowns and roots. Symptoms expanded to the upper stems, leaving vascular tissues exposed. During April 2010, samples from 2 fields were brought to the laboratory where the stems were washed thoroughly and disinfected with a 1% bleach solution for 2 minutes. Small pieces (5 mm in diameter) were removed from the lesion edge, plated on V8 agar (V8A) plates, and incubated at 24°C in the dark for 5 days. Four isolates were transferred to V8A using hyphal tips. Morphological studies were performed on the V8A cultures as well as plates flooded with tap water. Sporangia were obpyriform, nonpapillate, persistent, and variable in size, averaging 44 × 28 μm. Each isolate belonged to the A1 mating type when paired with P. capsici tester isolates, CBS 370.72 and CBS 111.334 (Fungal Biodiversity Centre, CBS, Utrecht, the Netherlands). The isolates produced amphigynous antheridia, and chlamydospores were present but scarce. Maximum temperatures for growth (37°C) were also performed. Edited sequences of the internal transcribed spacer (ITS) region of the rDNA (GenBank Accession Nos. JQ653300, JQ653301, JQ653302, and JQ653303) were compared with Phytophthora sequences available in GenBank using the BLASTN search utility (1) and aligned to the data set of Cooke et al. (2). Sequences of the four isolates (strains 2: R-cai-cuello-col-3, 3: R-cai-cuello-col-18, 4: R-AN-col-1A and 5: R-AN-col-1B) matched 100% with GenBank sequences of P. drechsleri (100% coverage, 100% identity and no gaps). Based on these results, the four Argentinian cabbage isolates were identified as P. drechsleri (3). Pathogenicity tests were completed using three detached heads of mature cabbage plants (B. oleracea var. capitata) for each isolate. A 5-mm colonized mycelial plug of the appropriate isolate was placed on the main vein of the outermost leaves. For the control treatments, three heads were inoculated with non-colonized V8A plugs. The inoculated and control heads of cabbage were incubated in plastic boxes wrapped in black nylon bags at 24°C for 4 days. Broccoli (B. oleracea var. italica) and cauliflower (B. oleracea var. botrytis) were also tested following the same procedure. All heads of cabbage, broccoli, and cauliflower developed necrotic lesions 2 to 4 cm in diameter and a dark grey color. Control heads of each plant remained green. P. dreschleri was consistently reisolated as described above from the inoculated heads, but not from the control heads. To our knowledge, this is the first report of cabbage as a host for P. dreschleri in Argentina. Frezzi (4) reported this species as a pathogen of Chrysanthemum cinerariefolium, Celosia plumosa, Schinus molle, and Solanum lycopersicum in Argentina in 1950. References: (1) S. S. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) D. E. L. Cooke et al. Fungal Gen. Biol. 30:17, 2000. (3) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Society Press, St. Paul, MN, 1996. (4) M. J. Frezzi. Rev. Invest. Agric. Buenos Aires 4:49, 1950.

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First Report of Powdery Mildew on Heath Aster Caused by Erysiphe cichoracearum in Argentina

Plant Disease ◽

10.1094/pdis.2000.84.9.1044a ◽

2000 ◽

Vol 84 (9) ◽

pp. 1044-1044

Author(s):

S. Wolcan ◽

L. Ronco

Keyword(s):

Powdery Mildew ◽

Buenos Aires ◽

Morphological Characteristics ◽

Buenos Aires Province ◽

Abaxial Surface ◽

Basal Ring ◽

First Report ◽

Erysiphe Cichoracearum ◽

Aster Ericoides ◽

Germ Tubes

In 1995, powdery mildew was observed on commercial greenhousegrown Aster ericoides L. from La Plata, Buenos Aires Province. The disease affected about 95% of the growers. Mildew first appeared as white circular patches on the adaxial surface of leaves. As disease progressed, the abaxial surface of leaves, petioles, stems, and calyces were covered by cottony masses of mycelium and conidia, and basal leaves later wilted and died. Young plants (4 to 5 leaves) through flowering plants were affected. Conidia were ovoid-cylindrical, often slightly constricted at the ends, and were produced in chains on unbranched conidiophores. Conidia lacked fibrosin bodies and ranged from 30 to 41 μm × 10 to 19 μm. Long unbranched germ tubes were formed from the ends of conidia. The morphological characteristics of the fungus fit those described for Erysiphe cichoracearum DC (1). In addition, the perfect stage was found on older tissues. Subglobose, dark brown cleistothecia (105 to 210 μm in diameter) with a basal ring of myceloid appendages were observed. Cleistothecia contained multiple ellipsoid asci (48 to 69 μm × 30 to 37 μm) with two hyaline, one-celled, ellipsoid ascospores (22 to 26 μm × 11 to 15 μm). Pathogenicity was tested by pressing diseased leaves onto healthy leaves of aster cv. Sunset and incubating plants in humidity chambers for 48 h. The powdery mildew that developed was morphologically identical to the original isolate. This is the first report of E. cichoracearum on heath aster in Argentina. Reference: (1) H. J. Boesewinkel. Bot. Rev. 46:167, 1980.

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First Report of Resistance to Metalaxyl in Downy Mildew of Sunflower Caused by Plasmopara halstedii in Spain

Plant Disease ◽

10.1094/pdis.2003.87.6.749c ◽

2003 ◽

Vol 87 (6) ◽

pp. 749-749 ◽

Cited By ~ 6

Author(s):

M. L. Molinero-Ruiz ◽

J. M. Melero-Vara ◽

T. J. Gulya ◽

J. Dominguez

Keyword(s):

Downy Mildew ◽

Plant Disease ◽

Disease Incidence ◽

Aqueous Suspension ◽

Plasmopara Halstedii ◽

First Report ◽

Metalaxyl Resistance ◽

Entire Plant ◽

Humidity Chamber ◽

Plant Pathol

Fifty-two isolates of Plasmopara halstedii Farl. Berl. & de Toni (causal agent of sunflower downy mildew) collected from sunflower (Helianthus annuus L.) in Spain from 1994 to 2000 were evaluated for metalaxyl resistance. The pathogen was identified on the basis of the morphology of the sporangiophores and zoosporangia recovered on the underside of the leaves (2). Metalaxyl (Apron 20% LS) at 2.0 g a.i./kg of seed (labeled European rate) was applied as seed dressing to the susceptible sunflower ‘Peredovik’. There were two replications of 40 plants, and the test was repeated three times. Inoculum (sporangia bearing zoospores) was produced on artificially inoculated plants. Seed were germinated in a humidity chamber at 28°C for 24 to 48 h. When the radicle was 0.5 to 1.0 cm long, untreated and treated seedlings were inoculated by dipping the entire plant in an aqueous suspension of 6.0 × 104 sporangia per ml for 4 h, planted in a sand/perlite mixture (2:3 vol/vol), and grown at 16 to 21°C with a 12-h photoperiod. Plants were incubated for 24 to 48 h at 100% relative humidity and 15°C in the dark to enhance sporulation. After 12 days, disease incidence (DI) of inoculated plants was determined as a percentage of plants displaying sporulation of the fungus on the cotyledons and/or true leaves (3). DI was 95 to 100% for the untreated seedlings, but mildew did not develop on seedlings treated with metalaxyl for 51 of the isolates. The remaining isolate caused symptoms on 67% of the treated plants. This isolate was tested in another experiment in which ‘Peredovik’ seed was treated with metalaxyl at 0, 0.5, 2.0, 3.5, and 5 g a.i./kg of seed. There were four replications of 12 seedlings per treatment, and seedlings were inoculated as described previously. DI in the untreated control was 77%, which was not significantly different from the DI for seed treated with metalaxyl at 0.5, 2.0, and 3.5 g a.i./kg of seed (97, 73, and 96%, respectively). DI for seed treated with metalaxyl at 5.0 g a.i./kg of seed was 37%, which was significantly lower than the other treatments. Although resistance of P. halstedii to metalaxyl has been reported in France (1), to our knowledge, this is the first report of resistance of sunflower downy mildew to metalaxyl in Spain. References: (1) J. M. Albourie et al. Eur. J. Plant Pathol. 104:235, 1998. (2) G. Hall, Mycopathologia 106:205, 1989. (3) M.L. Molinero-Ruiz et al. Plant Disease 86:736, 2002.

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First report of Trichinella spiralis from the white-eared (Didelphis albiventris) and the thick-tailed opossum (Lutreolina crassicaudata) in central Argentina

Helminthologia ◽

10.2478/s11687-014-0229-4 ◽

2014 ◽

Vol 51 (3) ◽

pp. 198-202 ◽

Cited By ~ 2

Author(s):

R. Castaño Zubieta ◽

M. Ruiz ◽

G. Morici ◽

R. Lovera ◽

M. Fernández ◽

...

Keyword(s):

Buenos Aires ◽

Trichinella Spiralis ◽

Enzymatic Digestion ◽

Animal Origin ◽

Buenos Aires Province ◽

First Report ◽

Domestic Cycle ◽

Undercooked Meat ◽

Didelphis Albiventris ◽

Lutreolina Crassicaudata

AbstractTrichinellosis is a zoonotic disease caused by nematodes of the genus Trichinella. Humans, who are the final hosts, acquire the infection by eating raw or undercooked meat of different animal origin. Trichinella spiralis is an encapsulated species that infects mammals and is widely distributed in different continents. In Argentina, this parasite has been reported in the domestic cycle that includes pigs and synanthropic hosts (mainly rats and some carnivores). This is the first report of T. spiralis in the opossums Didelphis albiventris and Lutreolina crassicaudata in Argentina, and the first report in opossums in South America. In this survey, Trichinella larvae were detected by enzymatic digestion in three D. albiventris and one L. crassicaudata captured on pig and dairy farms located in the northeast of Buenos Aires province. The microscopic examination of the 32 larvae isolated presented the diagnostic characteristic of the genus Trichinella. Two larvae isolated from two D. albiventris and one from L. crassicaudata were identified as T. spiralis by nested multiplex PCR and confirmed by sequencing. Further research to determine the burdens of T. spiralis in opossums may contribute to a better understanding of the risk of T. spiralis transmission to the synanthropic populations.

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First Report of Fusarium solani Causing Root Rot of Olive in Southeastern Argentina

Plant Disease ◽

10.1094/pdis-02-11-0095 ◽

2011 ◽

Vol 95 (11) ◽

pp. 1476-1476 ◽

Cited By ~ 1

Author(s):

B. A. Perez ◽

O. M. Farinon ◽

M. F. Berretta

Keyword(s):

Fusarium Solani ◽

Root Rot ◽

Buenos Aires ◽

Average Length ◽

Fusarium Species ◽

Morphological Identification ◽

Buenos Aires Province ◽

Blue Color ◽

First Report ◽

Olive Trees

In Argentina, olive (Olea europaea L.) is cultivated in the mountainous, warm, arid northwest (Andes range), where Fusarium solani (blue sporodochia) is frequently found to be causing death of nursery and young field plants (1). Recently, olive orchards were established more than 1,600 km to the southeast (Pampas) in a plain with a temperate and humid climate and in the arid Patagonia, both influenced by the Atlantic Ocean. This area includes part of Buenos Aires and Rio Negro provinces. In March 2008, 10-year-old ‘Barnea’ olive trees with high incidence of root rot, dried leaves, dead branches, and dead plants were observed in the Coronel Dorrego District of Buenos Aires Province, where oat, barley or other cereals are planted between rows of olive trees. Planting material originated from olive nurseries located in Mendoza Province, 1,200 km from Coronel Dorrego. Diseased roots were disinfected in 2% NaOCl and 70% ethanol, cut into small pieces, plated onto rose bengal-glycerin-urea medium, and incubated at 20°C with a 12-h photopheriod. A fungus was purified through successive transfers of hyphal tips from the margin of a sparsely growing colony onto 2% water agar (2). Colonies grown on Spezieller Nährstoffarmer agar (3) and carnation leaf-piece agar were used for morphological identification, and those on grown on potato dextrose agar were used for evaluation of pigmentation and colony growth rate. Sporodochium color, cream, was typical of F. solani (Mart.) Sacc. This isolate was deposited in the IMYZA Microbial Collection as INTA-IMC 73. Mycelium was cultured in liquid Czapek-Dox medium supplemented with sucrose, peptone, yeast extract, sodium nitrate, and vitamins for 4 days and fungal DNA was obtained with a DNA extraction kit. Primers ITS1 and ITS4 were used to amplify the internal transcribed spacer (ITS) region of ribosomal genes. The purified PCR product was sequenced and the DNA sequence compared with GenBank records. The sequence shared 100% identity with 27 entries for F. solani and 97% identity with F. solani obtained from olive in Nepal (4), corresponding to EU912432 and EU912433. The nucleotide sequence was registered in GenBank as JF299258. Pathogenicity was confirmed on ‘Manzanilla’ plants at the eight-leaf stage. Pieces of water agar with mycelium were applied to small wounds at the stem base and on roots of 10 plants and were covered with cotton soaked in sterile distilled water. Plants were incubated at 20°C and a 14-h photoperiod. On control plants, water agar pieces without mycelium were applied to the wounds. After 33 days, inoculated plants showed dark brown lesions (average length 1.4 cm) and leaf chlorosis. Two plants showed wilting with leaves remaining attached to branches. F. solani was reisolated from roots and stem bases of inoculated plants. Controls remained asymptomatic. To our knowledge, this is the first report of F. solani occurring on olive in the temperate part of the Pampas of Argentina where cereals, which are susceptible to Fusarium species, are grown with olive trees. Sporodochium color (cream) of these isolates differed from the blue color of previously reported isolates of F. solani on olive in northwestern Argentina (1). References: (1) S. Babbitt et al. Plant Dis. 86:326, 2002. (2) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell Publishing, Ames, IA, 2006. (3) H. I. Nirenberg. Releases Fed. Biol. Res. Center Agric. For. (Berlin-Dahlem) 169:1, 1976. (4) A. M. Vettraino et al. Plant Dis. 23:200, 2009.

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