scholarly journals First Report of Cylindrocarpon liriodendri Causing Black Foot Disease of Grapevine in California

Plant Disease ◽  
2007 ◽  
Vol 91 (8) ◽  
pp. 1060-1060 ◽  
Author(s):  
E. Petit ◽  
W. D. Gubler
Keyword(s):  
South Africa ◽  
South African ◽  
Ribosomal Dna ◽  
Dna Sequences ◽  
Small Subunit ◽  
The South ◽  
First Report ◽  
Foot Disease ◽  
Black Foot ◽  
Black Foot Disease

Black foot disease is a recently identified but worsening problem in vineyards worldwide (2). Roots of symptomatic grapevines show black, sunken, necrotic lesions (2). In cross section, the base of the trunk appears necrotic and xylem vessels are plugged with black inclusions and tyloses (2). Aboveground, leaves of infected vines appear to be scorched, and the entire vine becomes stunted and frequently dies (2). In California, we previously identified two Cylindrocarpon species as causal agents of this disease: C. macrodidymum and C. destructans (2). In earlier molecular phylogenetic studies, tremendous variation in C. destructans from diverse hosts was found, indicating that this species might encompass more than one species (2). On the basis of analysis of sequences of three independent DNA regions, we concluded that the group of C. destructans isolated from grapevines in France, South Africa, and California have nearly identical sequences and form a well-supported sister clade divergent from the clade containing C. destructans found in numerous hosts (2). Further studies compared DNA sequences of C. destructans causing black foot in France, Portugal, and South Africa with an ex-type strain of C. liriodendri isolated from tulip poplar (Liriodendron tulipifera) (1). Because these species had identical sequences, C. destructans causing black foot in France, Portugal, and South Africa was renamed C. liriodendri (1). The objective of the current study was to clarify the taxonomy of C. destructans causing black foot in California. We compared C. liriodendri isolate CBS112602 from South Africa (1) with three C. destructans isolates (USME116, USST148, and USSO150) from California (2). We analyzed four sequences on three genomic regions: the internal transcribed spacer of ribosomal DNA, partial sequences of the beta tubulin gene, and the mitochondrial small subunit ribosomal DNA. We used sequences from the South African C. liriodendri isolate CBS112602 (AY997566, AY997586, AY997581, and AY997532) and sequences from Californian isolates of C. destructans (AY997568, AY997588, AY997534, AY997583, AY997569, AY997601, AY997547, AY997584, AY997570, AY997598, AY997544, and AY997585) previously deposited in GenBank (2). Sequences were aligned using Clustal X 1.8 (3). On the basis of visual inspection of each DNA region alignment, the South African C. liriodendri isolate was identical to Californian isolates of C. destructans. Thus, Californian isolates of C. destructans causing black foot (2) are renamed C. liriodendri. To our knowledge, this is the first report of C. liriodendri causing black foot disease of grapevine in California. References: (1) F. Halleen et al. Stud. Mycol. 55:227, 2006. (2) E. Petit and W. D. Gubler. Plant Dis. 89:1051, 2005. (3) J. D. Thompson et al. Nucleic Acids Res. 25:4876, 1997.

scholarly journals First Report of Leaf Rust of Blueberry Caused by Thekopsora minima on Vaccinium corymbosum in the Western Cape, South Africa

Plant Disease ◽  
2010 ◽  
Vol 94 (4) ◽  
pp. 478-478 ◽  
Author(s):  
L. Mostert ◽  
W. Bester ◽  
T. Jensen ◽  
S. Coertze ◽  
A. van Hoorn ◽  
...  
Keyword(s):  
South Africa ◽  
South African ◽  
Water Solution ◽  
Phylogenetic Analyses ◽  
The United States ◽  
Vaccinium Corymbosum ◽  
Tween 20 ◽  
Western Cape ◽  
The South ◽  
First Report

Southern highbush blueberry plants (Vaccinium corymbosum interspecific hybrids) showing rust-like symptoms were observed in July 2006 in Porterville in the Western Cape (WC), South Africa. Diseased plants were also found in Villiersdorp and George in the WC in 2007. In 2008, symptoms were observed in George, and in 2009, in all the previous reported areas. Cvs. Bluecrisp, Emerald, Jewel, Sharpblue, and Star were infected. Reddish-to-brown spots appeared on the adaxial surface of leaves and developed into yellow-to-orange erumpent uredinia with pulverulent urediniospores. Uredinia were hypophyllous, dome shaped, 113 to 750 μm wide, and occasionally coalescing. Urediniospores were broadly obovate, sometimes ellipsoidal or pyriform, with yellowish orange content, and measured 19 to 27 × 12 to 20 μm (average 24 × 15 μm, n = 30). Spore walls were echinulate, hyaline, 1 to 1.5 μm thick, and with obscure germ pores. No telia or teliospores were observed. Voucher specimens were lodged in the South African National Fungus Collection in Pretoria (PREM 60245). The isolate was initially identified as Thekopsora minima P. Syd. & Syd., based primarily on the absence of conspicuous ostiolar cells characteristic of Naohidemyces spp. (3). Genomic DNA was extracted from urediniospores. Approximately 1,400 bp were amplified spanning the 5.8S, ITS2, and 28S large subunit of the ribosomal DNA (1). The sequence (GU355675) shared 96% (907 of 942 bp; GenBank AF522180) and 94% (1,014 of 1,047 bp; GenBank DQ354563) similarities in the 28S portion, respectively, to those of Naohidemyces vaccinii (Wint.) Sato, Katsuya et Y. Hiratsuka and Pucciniastrum geoppertianum (Kuehn) Kleb, two of the three known rust species of blueberry (2). Although no sequences of T. minima were available for direct comparison, phylogenetic analyses of the 28S region strongly supported the South African blueberry rust as congeneric with T. guttata (J. Schröt.) P. Syd. & Syd. (GenBank AF426231) and T. symphyti (Bubák) Berndt (GenBank AF26230) (data not shown). Four 6-month-old cv. Sharpblue plants were inoculated with a suspension (approximate final concentration of 1 × 105 spores per ml) of fresh urediniospores in a water solution with 0.05% Tween 20. After incubation at 20°C for 48 h under continuous fluorescent lighting, the plants were grown in a glasshouse (18/25°C night/day temperatures). Identical uredinia and symptoms developed approximately 3 weeks after inoculation on the inoculated plants, but not on two control plants of cv. Sharpblue sprayed with distilled water and kept at the same conditions. The alternate host hemlock (Tsuga spp.) is not endemic to South Africa and not sold as an ornamental plant according to a large conifer nursery. Hosts of T. minima include Gaylussacia baccata, G. frondosa, Lyonia neziki, Menziesia pilosa, Rhododendron canadense, R. canescens, R. lutescens R. ponticum, R. prunifolium, R. viscosum, V. angustifolium var. laevifolium, V. corumbosum, and V. erythrocarpon (3). Visual inspection of possible hosts in the gardens in close proximity of Vaccinium production areas did not show any rust symptoms. To our knowledge, this is the first report of T. minima on blueberries outside of Asia and the United States (2). References: (1) M. C. Aime. Mycoscience 47:112, 2006. (2) D. F. Farr and A. Y. Rossman. Fungal Databases. Systematic Botany and Mycology Laboratory. Online publication. USDA-ARS, 2009. (3) S. Sato et al. Trans. Mycol. Soc. Jpn. 34:47, 1993.

scholarly journals First Report of Maize streak virus Field Infection of Sugarcane in South Africa

Plant Disease ◽  
2008 ◽  
Vol 92 (6) ◽  
pp. 982-982 ◽  
Author(s):  
T. van Antwerpen ◽  
S. A. McFarlane ◽  
G. F. Buchanan ◽  
D. N. Shepherd ◽  
D. P. Martin ◽  
...  
Keyword(s):  
South Africa ◽  
South African ◽  
Southern Africa ◽  
Maize Streak Virus ◽  
Streak Virus ◽  
Yield Losses ◽  
The South ◽  
Sugarcane Cultivar ◽  
First Report ◽  
The Impact

Prior to the introduction of highly resistant sugarcane varieties, Sugarcane streak virus (SSV) caused serious sugar yield losses in southern Africa. Recently, sugarcane plants with streak symptoms have been identified across South Africa. Unlike the characteristic fine stippling and streaking of SSV, the symptoms resembled the broader, elongated chlorotic lesions commonly observed in wild grasses infected with the related Maize streak virus (MSV). Importantly, these symptoms have been reported on a newly released South African sugarcane cultivar, N44 (resistant to SSV). Following a first report from southern KwaZulu-Natal, South Africa in February 2006, a survey in May 2007 identified numerous plants with identical symptoms in fields of cvs. N44, N27, and N36 across the entire South African sugarcane-growing region. Between 0.04 and 1.6% of the plants in infected fields had streak symptoms. Wild grass species with similar streaking symptoms were observed adjacent to one of these fields. Potted stalks collected from infected N44 plants germinated in a glasshouse exhibited streak symptoms within 10 days. Virus genomes were isolated and sequenced from a symptomatic N44 and Urochloa plantaginea plants collected from one of the surveyed fields (1). Phylogenetic analysis determined that while viruses from both plants closely resembled the South African maize-adapted MSV strain, MSV-A4 (>98.5% genome-wide sequence identity), they were only very distantly related to SSV (~65% identity; MSV-Sasri_S: EU152254; MSV-Sasri_G: EU152255). To our knowledge, this is the first confirmed report of maize-adapted MSV variants in sugarcane. In the 1980s, “MSV strains” were serologically identified in sugarcane plants exhibiting streak symptoms in Reunion and Mauritius, but these were not genetically characterized (2,3). There have been no subsequent reports on the impact of such MSV infections on sugarcane cultivation on these islands. Also, at least five MSV strains have now been described, only one of which, MSV-A, causes significant disease in maize and it is unknown which strain was responsible for sugarcane diseases on these islands in the 1980s (2,3). MSV-A infections could have serious implications for the South African sugar industry. Besides yield losses in infected plants due to stunting and reduced photosynthesis, the virus could be considerably more difficult to control than it is in maize because sugarcane is vegetatively propagated and individual plants remain within fields for years rather than months. Moreover, there is a large MSV-A reservoir in maize and other grasses everywhere sugarcane is grown in southern Africa. References: (1) B. E. Owor et al. J Virol. Methods 140:100, 2007. (2) M. S. Pinner and P. G. Markham. J. Gen. Virol. 71:1635, 1990. (3) M. S. Pinner et al. Plant Pathol. 37:74, 1998.

scholarly journals First Report of Ilyonectria robusta Causing Black Foot Disease of Grapevine in Spain

Plant Disease ◽  
2018 ◽  
Vol 102 (11) ◽  
pp. 2381-2381 ◽  
Author(s):  
M. P. Martínez-Diz ◽  
E. Díaz-Losada ◽  
J. Armengol ◽  
M. León ◽  
C. Berlanas ◽  
...  
Keyword(s):  
First Report ◽  
Foot Disease ◽  
Black Foot ◽  
Black Foot Disease

scholarly journals First Report of Campylocarpon fasciculare Causing Black Foot Disease of Grapevine in Turkey

Plant Disease ◽  
2014 ◽  
Vol 98 (9) ◽  
pp. 1277-1277 ◽  
Author(s):  
D. S. Akgül ◽  
N. G. Savaş ◽  
S. Önder ◽  
S. Özben ◽  
S. Kaymak
Keyword(s):  
Vitis Vinifera ◽  
Dna Sequences ◽  
Histone H3 ◽  
Conidial Suspension ◽  
Water Control ◽  
Western Turkey ◽  
Foot Disease ◽  
Black Foot ◽  
Black Foot Disease ◽  
Β Tubulin

Soil-borne fungal diseases have become an important problem in grapevine nurseries of the Aegean region (western Turkey) in recent years. Reduced vigor, black vascular streaking in basal ends, blackish-sunken necrotic root lesions, and young vine death were observed in 15 grapevine nurseries of Manisa city in May 2011 and 2012. To determine the causal agents, symptomatic young grapevine (Vitis vinifera cv. Sultana 7) plants (grafted on 1103 Paulsen) were collected from nurseries (8 to 10 plants from each). Symptomatic basal end tissues were surface disinfested with 95% ethanol and flame sterilized. The internal tissues were plated onto potato dextrose agar amended with tetracycline (0.01%). Campylocarpon-like fungi were isolated (with 37.9% isolation frequency) from only one nursery (corresponding to 6.7% of all surveyed nurseries). Fungal colonies were incubated for 21 days in the dark to induce sporulation. Fungal colonies produced cottony aerial mycelium and turned chocolate-brown to dark brown on PDA. Abundant macroconidia were observed at branched conidiophores on long and cylindrical phialides. Microconidia were not observed. Macroconidia were generally 2 to 4 septate, cylindrical and slightly curved, with the following dimensions: 2 septate: 33.5 to 40.7 × 6.1 to 7.6 μm (mean: 35.9 × 6.8 μm), 3 septate: 36.2 to 43.4 × 6.6 to 8.3 μm (mean: 37.3 × 7.6 μm), and 4 septate: 48.9 to 53.5 × 7.6 to 8.3 μm (mean: 50.7 × 8.0 μm). Fifty macroconidia were measured. Morphologically, the isolates resembled the published description of Campylocarpon fasciculare Schroers, Halleen & Crous (2,4). For molecular identification, fungal DNA was extracted from mycelium and ribosomal DNA fragments (ITS1, 5.8S ITS2 rDNA), β-tubulin, and histone H3 genes, amplified with ITS 4-5, Bt 2a-2b, and H3 1a-1b primers (3,5), and sequenced. Sequences were compared with those deposited in GenBank. The isolate (MBAi45CL) showed 99% similarity with Campylocarpon fasciculare isolates AY677303 (ITS), AY377225 (β-tubulin), and JF735502 (histone H3). The DNA sequences were deposited into GenBank under accessions KJ573392, KJ573393, and KJ573394 for ITS, β-tubulin, and Histone H3 genes, respectively. To fulfill Koch's postulates, pathogenicity tests were conducted under greenhouse conditions on own-rooted grapevines (Vitis vinifera) cv. Sultana 7. Plants were removed from the rooting bench and the roots were slightly trimmed and submerged in a 107 ml–1 conidial suspension of the isolate for 60 min (5). After inoculation, the rooted cuttings were planted in 1-liter bags containing a mixture of soil, peat, and sand (2:1:1, v/v/v), and maintained in the greenhouse (24°C. 16/8-h day/night, 75% RH). Ten plants were inoculated with the isolate and five plants were submerged in sterile distilled water (control). After 4 months, young vines were examined for vascular discoloration, reduced root biomass, blackish lesions, and recovery of fungal isolates. The experiment was repeated twice. Blackish-brown discoloration of xylem vessels and necrosis in the basal ends was visible in the inoculated plants but not in the control plants. The pathogen was successfully re-isolated from 69.1% of the inoculated plants. This report is important for the new studies aiming at black foot disease control in Turkey viticulture. References: (1) A. Cabral et al. Phytopathol. Mediterr. 51:340, 2012. (2) P. Chaverri et al. Stud. Mycol. 68:67, 2011. (3) N. L. Glass and G. C. Donaldson. Appl. Environ. Microbiol. 61:1323, 1995. (4) F. Halleen et al. Stud. Mycol. 50:431, 2004. (5) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990.

scholarly journals First Report of Ilyonectria robusta Associated with Black Foot Disease of Grapevine in the United States

Plant Disease ◽  
2019 ◽  
Vol 103 (7) ◽  
pp. 1788-1788
Author(s):  
R. Guggenheim ◽  
A. Oropeza ◽  
S. Keith ◽  
R. Maggard ◽  
J. W. Woodhall
Keyword(s):  
United States ◽  
The United States ◽  
First Report ◽  
Foot Disease ◽  
Black Foot ◽  
Black Foot Disease

scholarly journals First Report of Black Foot Disease of Grapevine Caused by Cylindrocarpon macrodidymum in Chile

Plant Disease ◽  
2007 ◽  
Vol 91 (4) ◽  
pp. 470-470 ◽  
Author(s):  
J. Auger ◽  
M. Esterio ◽  
I. Pérez
Keyword(s):  
Vascular Tissue ◽  
Disease Incidence ◽  
Phylogenetic Analyses ◽  
Abnormal Development ◽  
Vitis Vinifera L ◽  
First Report ◽  
Vascular Elements ◽  
Foot Disease ◽  
Black Foot ◽  
Black Foot Disease

Black foot disease, caused by Cylindrocarpon macrodidymum Halleen, Schroers & Crous, is reported damaging table and wine grapes (Vitis vinifera L.) for the first time in Chile. During the summer of 2006, 2- to 5-year-old grapevines showed reduced vigor, shortened internodes, and drying and dying shoots along with abnormal development of roots with growth parallel to the soil surface, necrotic root crowns, and development of secondary roots. Internal necrosis extended from the bark to the pith in diseased parts of the plants. Other symptoms included black discoloration of the wood, gum inclusions in xylem vessels, black streaks in the vascular tissue, and reduction in root biomass, with sunken, necrotic root lesions. Eighteen Cylindrocarpon isolates were collected from roots, vascular elements, and pith tissue of grapevines cultivars (Flame Seedless, Red Globe, Thompson Seedless, Merlot, Carmenere, and Cabernet Sauvignon) from 12 locations in Chile. The isolates were identified on the basis of morphological features. All isolates produced micro- and macroconidia (one to three septa) and chlamydospores in short and intercalary chains (1,4), and by internal transcribed spacer (ITS1-5,8S-ITS4) rDNA and β -tubulin (BT1, and BT2) partial sequences, identical to those of C. macrodidymum (isolate USS074, GenBank Accession No. AY 997558 and isolate USSO150, GenBank Accession No. AY 997598) (2). Phylogenetic analyses placed these isolates in a clade closely related, but clearly distinct from other clades, to C. destructans and C. liriodendri (2,3). Pathogenicity tests were completed by drench inoculation onto 50 6-month-old rooted cuttings of ‘Red Globe’ with 25 ml of conidia suspension (106 conidia ml-1) obtained from four isolates. Ten control cuttings of ‘Red Globe’ were inoculated with an equal volume of sterile distilled water. The plants were incubated for 4 months in a controlled environment facility at 24°C. All isolates tested were pathogenic. In addition, they caused significant root rot (t-test of disease incidence, P = 0.0048) and no significant level of variation was detected between different isolates. C. macrodidymum was reisolated from the region of brown streaking in all the inoculated cuttings and was not isolated from the water-treated controls. To our knowledge, this is the first report of C. macrodidymum causing black foot disease on grapevine in Chile. References: (1) C. D. Booth. Mycol. Pap. (CMI) 104:1, 1966. (2) F. Halleen et al. Stud. Mycol. 50:431, 2004. (3) F. R. Mantiri et al. Can. J. Bot. 79:334, 2001. (4) E. Petit and W. D. Gubler. Plant Dis. 89:1051, 2005.

scholarly journals First Report of Cylindrocarpon macrodidymum Associated with Black Foot Diseases of Grapevine in Turkey

Plant Disease ◽  
2012 ◽  
Vol 96 (5) ◽  
pp. 762-762 ◽  
Author(s):  
S. Özben ◽  
F. Demirci ◽  
K. Değirmenci ◽  
S. Uzunok
Keyword(s):  
Vascular Tissue ◽  
Morphological Characteristics ◽  
First Report ◽  
Foot Diseases ◽  
Vascular Elements ◽  
Pathogenicity Tests ◽  
Foot Disease ◽  
Water Plants ◽  
Black Foot ◽  
Black Foot Disease

Grape (Vitis vinifera) is widely planted and is an economically important crop in Turkey for domestic consumption and export. Black foot disease, caused by Cylindrocarpon macrodidymum Halleen, Schroers & Crous, is a recently identified but worsening problem in vineyards worldwide (3,4). Symptomatic grapevines show reduced vigor, shortened internodes, small leaves with interveinal chlorosis, and necrosis frequently leading to the death of the plants (1). Roots of symptomatic grapevines exhibit black, sunken, necrotic lesions with a reduction in root biomass. Pith of affected vines is discolored (4). During the summers of 2009 and 2010, a survey was carried out in 63 vineyards (4 to 15 years old) in six locations of Ankara Province. We collected 44 samples from roots and crowns of grapevines exhibiting black foot symptoms. In cross section, extensive necrosis at the base of the trunk and brown-black spots in xylem vessels were observed, resembling those previously reported for black foot disease (2,4). Isolations were made from roots, vascular elements, and pith tissue. In this study, 26 isolates were identified as C. macrodidymum on the basis of morphological characteristics. Isolates identified as C. macrodidymum had a dark orange-brown colony color and abundant aerial mycelia when grown on potato dextrose agar. Isolates produced ellipsoid or ovoid microconidia. The macroconidia were one to three septate, straight, and cylindrical. One-septate macroconidia were 24 to 32 × 5 to 7 μm; three-septate macroconidia were 26 to 40 × 5 to 6 μm. Chlamydospores developed in short, intercalary chains. Conidiophores were simple or complex and sporodochial. Isolate identities were confirmed by sequence analysis of the ribosomal DNA internal transcribed spacer (GenBank Accession No. HM245331) with primers ITS1 and ITS4 (4). Isolates had 99% genetic identity with other isolates of C. macrodidymum present in GenBank. In pathogenicity tests, one representative isolate was used to inoculate five grapevine plants. Tests were completed by drench inoculation onto 3-month-old rooted cuttings of cv. Sultana with 25 ml of a conidia suspension (106 conidia ml–1). Controls were inoculated with an equal volume of sterile distilled water. Plants were incubated for 4 months in a controlled environment facility at 25°C. After 3 to 4 months, inoculations resulted in reduction of root mass, and C. macrodidymum was reisolated from regions of brown streaking in wood and discolored vascular tissue in all inoculated plants, fulfilling Koch's postulates. Control plants were asymptomatic and C. macrodidymum was not recovered from control plants. To our knowledge, this is the first report of the presence of C. macrodidymum causing black foot disease on grapevine in Turkey. References: (1) S. Alaniz et al. Plant Dis. 93:821, 2009. (2) F. Hallen et al. Stud. Mycol. 50:431, 2004. (3) F. Halleen et al. Phytopathol. Mediterr. 45:S55, 2006. (4) E. Petit and W. D. Gubler. Plant Dis. 89:1051, 2005.

scholarly journals First Report of “Cylindrocarpon” pauciseptatum Associated with Black Foot Disease of Grapevine in Brazil

Plant Disease ◽  
2014 ◽  
Vol 98 (4) ◽  
pp. 567-567 ◽  
Author(s):  
R. F. dos Santos ◽  
E. Blume ◽  
M. F. B. Muniz ◽  
S. M. Steckling ◽  
G. W. Burtet ◽  
...  
Keyword(s):  
Histone H3 ◽  
Vascular Lesions ◽  
Conidial Suspension ◽  
First Report ◽  
Rdna Its ◽  
Foot Disease ◽  
Histone H3 Gene ◽  
Black Foot ◽  
Black Foot Disease ◽  
Β Tubulin

Since 1999, the decline of American grapevines (Vitis labrusca L.) has been common in Rio Grande do Sul, Brazil (1). In August 2012, V. labrusca with black foot symptoms were collected in vineyards in the Serra Gaúcha Region. Symptomatic plants had low vigor, vascular lesions, delayed budding, and decline and death of vines. Symptomatic roots had necrotic lesions and reduced biomass. Fungal isolations were made from necrotic root and crown fragments (own-rooted cultivar) on potato dextrose agar (PDA) medium amended with 0.5 g L–1 streptomycin sulfate. Putative colonies of “Cylindrocarpon” pauciseptatum Schroers & Crous were obtained from single macroconidia isolations. Two isolates were used to confirm the identity of isolated colonies: Cy12UFSM and Cy13UFSM. After incubation in the dark for 10 days at 20°C, the isolated mycelial colonies, which were cottony white to felty in texture, became dark orange to brown. Both isolates produced chlamydospores in chains at 40 days. Chlamydospores of Cy12UFSM and Cy13UFSM were 9 to 12 μm and 5 to 11.5 μm in diameter. Sporodochia formation on carnation leaf agar (CLA) medium was observed after 30 days. To encourage development of conidia, the isolates were grown on spezieller nährstoffarmer agar (SNA) medium for five weeks at 20°C with addition of two pieces of 1 cm2 filter paper. Microconidia of Cy12UFSM were 4 to 8.5 × 3.5 to 5 μm and those of Cy13UFSM were 3.5 to 7.5 × 3 to 5 μm. Macroconida were predominantly 3-septate (Cy12UFSM was 36 to 45 × 7.5 to 9 μm and Cy13UFSM was 30 to 38 × 7.5 to 8 μm), but 1-, 2- septate macroconidia were observed. The sizes of the three spore types and colony morphology for our isolates were similar to those described by Schroers et al. (3) for “C.” pauciseptatum. To further confirm the identity of Cy12UFSM and Cy13UFSM, multi-gene DNA sequence analysis (rDNA-ITS, β-tubulin, and histone H3) was conducted using primer pairs ITS1 and ITS4 (4), Bt2a and Bt2b, and H3-1a and H3-1b (2), which amplify the ITS1-5.8S rRNA-ITS2 genes, part of the β-tubulin gene, and the histone H3 gene, respectively. Sequences of these three regions had 99, 99, and 97% similarity with references sequences of “C.” pauciseptatum (isolate Cy238; accessions ITS [JF735307]; β-tubulin [JF735435], and histone H3 [JF735582], respectively). To evaluate pathogenicity, 4-month-old rooted cuttings of V. labrusca cv. Bordô were inoculated with two isolates by immersing them in a conidial suspension (106 conidia ml–1) for 60 min. Ten single-vine replicates were used for each isolate, and 10 water-inoculated vines were included as controls. Thirty days after inoculation, vines were re-inoculated with 40 ml of a 106 conidia ml–1 suspension to ensure root infection. After 4 months, the inoculated plants had reduced root mass relative to controls (39.18% for Cy12UFSM and 18.27% for Cy13UFSM). Inoculated plants also had root and crown necrosis, vascular lesions, shoot decline, and vine mortality (60 and 80% mortality for Cy12UFSM and Cy13UFSM, respectively). All water-inoculated control plants remained symptomless. The fungi Cy12UFSM and Cy13UFSM were re-isolated from infected woody tissues, confirming Koch's postulates. To our knowledge, this is the first report of “C.” pauciseptatum associated with black foot disease of grapevine in Brazil, which may potentially impact the sustainability of grapevine nurseries and vineyard productivity. References: (1) L. R. Garrido et al. Fitopatol. Brasil. 29:548, 2004. (2) N. L. Glass et al. Appl. Environ. Microbiol. 61:1323, 1995. (3) H. J. Schoers et al. Mycol. Res. 112:82, 2008. (4) T. J. White et al. Amplification Pages 315-322 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990.

scholarly journals First Report of Campylocarpon fasciculare Causing Black Foot Disease of Grapevine in Spain

Plant Disease ◽  
2011 ◽  
Vol 95 (8) ◽  
pp. 1028-1028
Author(s):  
S. Alaniz ◽  
C. Agustí-Brisach ◽  
D. Gramaje ◽  
M. I. Aguilar ◽  
A. Pérez-Sierra ◽  
...  
Keyword(s):  
Tap Water ◽  
Peat Moss ◽  
Vitis Vinifera L ◽  
Sodium Hypochlorite Solution ◽  
Distilled Water ◽  
Internal Transcribed Spacer Region ◽  
First Report ◽  
Foot Disease ◽  
Black Foot ◽  
Black Foot Disease

In May 2008, symptoms of black foot disease were observed on 8-year-old grapevines (Vitis vinifera L.) cv. Garnacha in Albuñol (Granada Province, southern Spain). Affected plants showed delayed budding with low vigor. Roots showed black discoloration and necrosis of wood tissues. Root fragments were cut, washed under running tap water, surface sterilized for 1 min in a 1.5% sodium hypochlorite solution, and washed twice with sterile distilled water. Small pieces of discolored or necrotic tissues were plated onto potato dextrose agar (PDA) supplemented with 0.5 g liter–1 of streptomycin sulfate. Plates were incubated at 25°C in the dark for 10 days and all colonies were transferred to PDA. A Cylindrocarpon-like fungus was consistently isolated from necrotic root tissues. Single conidial isolates were obtained and grown on PDA and Spezieller Nährstoffarmer Agar (SNA) and incubated at 25°C for 10 days in darkness. On PDA, the isolates developed white, thick, and cottony to felty abundant mycelium. On SNA, all isolates produced slightly to moderately curved one-septate (22.5-) 25.6 (-27.5) × (5-) 5.63 (-6.25) μm, two-septate (30-) 36.1 (-45) × (6.25-) 7.08 (-7.5) μm, three-septate (37.5-) 47.9 (-52.5) × (6.25-) 7.5 (-8.75) μm, four-septate (47.5-) 53.3 (-62.5) × (7.5-) 7.89 (-8.75) μm, and five-septate (52.5-) 61.8 (-67.5) × (7.5-) 8 (-8.75) μm macroconidia. Microconidia were not observed. DNA sequence of the rDNA internal transcribed spacer region (ITS) was obtained for isolate Cf-270 and deposited in GenBank (Accession No. HQ441249). This sequence showed high similarity (99%) to the sequence of Campylocarpon fasciculare Schroers, Halleen & Crous (GenBank Accession No. AY677303), in agreement with morphological features (1). Pathogenicity tests were conducted with inoculum produced on wheat (Triticum aestivum L.) seeds that were soaked for 12 h in flasks filled with distilled water. Each flask contained 300 ml of seeds that were subsequently autoclaved three times after excess water was drained. Two fungal disks of a 2-week-old culture of C. fasciculare (isolate Cf-270) grown on PDA were placed aseptically in each flask. The flasks were incubated at 25°C for 4 weeks and shaken once a week to avoid clustering of inoculum. Plastic pots (220 cm3) were filled with a mixture of sterilized peat moss and 10 g of inoculum per pot. One-month-old grapevine seedlings were planted individually in each pot and placed in a greenhouse at 25 to 30°C in a completely randomized design. Control plants were inoculated with sterile uninoculated seeds. Six replicates (each one in individual pots) were used, with an equal number of control plants. The experiment was repeated. Symptoms developed on all plants 20 days after inoculation and consisted in reduced vigor, interveinal chlorosis and necrosis of the leaves, necrotic root lesions with a reduction in root biomass, and plant death. The fungus was reisolated from the roots of affected seedlings and identified as C. fasciculare, completing Koch's postulates. No symptoms were observed on the control plants. Black foot disease of grapevines can be caused by different species of Cylindrocarpon and Campylocarpon. C. fasciculare was first reported in South Africa in 2004 (1). To our knowledge, this is the first report of C. fasciculare causing black foot disease of grapevine in Spain as well as other countries in Europe. Reference: (1) F. Halleen et al. Stud. Mycol. 50:431, 2004.

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