First Report of Crown Rot Caused by Cylindrocladium pauciramosum on Scarlet Honey Myrtle in Italy

Scarlet honey myrtle (Melaleuca fulgens R. Br.), native to Australia, is an evergreen colorful shrub (Myrtaceae) and grown in Italy as an ornamental plant. During November 2008, a widespread disease was noticed on ~90% of 3,000 6-month-old M. fulgens cv. Red potted plants. Plants were obtained from cuttings and produced by a commercial nursery in Catania Province. Symptomatic plants showed a crown rot and longitudinal sections of tissues revealed a brown discoloration of the basal stem. As a consequence, leaves gradually became necrotic and abscised, followed by death of the entire plant. Root rots and leaf spots were not observed. M. gibbosa, M. ericifolia, M. thymifolia, and M. elliptica, cultivated in the same nursery, did not show disease symptoms. A Cylindrocladium sp. was consistently isolated from the crown and basal stem of symptomatic plants on potato dextrose agar (1). Ten Cylindrocladium isolates obtained from infected basal stems and crowns were selected and cultured for 8 days at 25°C on carnation leaf agar (CLA). Macroconidiophores consisted of a stipe, a penicillate arrangement, and a stipe extension terminating in an obpyriform to ellipsoidal vesicle (6 to 10 μm in diameter). Cylindrical conidia were rounded at both ends, straight, 1-septate, and 42 to 60 × 4 to 5 μm. All single-conidial isolates were mated with opposite tester strains of C. pauciramosum on CLA and produced fertile perithecia (3). Perithecia were solitary or in groups, orange to red-brown, subglobose to ovoid, and 270 to 400 μm high × 180 to 290 μm in diameter. Further confirmation of species was obtained by amplification and sequencing of the intergenic spacer (IGS) region of rDNA with the M13 forward (-20) and M13 reverse primers. On the basis of the complete IGS sequence, two primer sets (218F/218R and 106F/106R) were designed and successfully used in a nested-PCR protocol for the detection of C. pauciramosum from tissues of infected plants (2). On the basis of morphological characters, mating type, and molecular data, the isolates were identified as C. pauciramosum C.L. Schoch & Crous. One representative isolate (DISTEF-MFR2; CBS 124657) was deposited at Centraalbureau voor Schimmelcultures open fungi collection (Fungal Biodiversity Centre, Utrecht, the Netherlands). Pathogenicity tests were performed by adding sterile water to CLA cultures of C. pauciramosum from a single-conidial isolate and incorporating the resulting spore suspension (105 conidia per ml) on the soil surface of 20 3-month-old M. fulgens cv. Red potted plants. The same number of plants served as uninoculated controls. Following inoculation, plants were well irrigated and maintained in a growth chamber at 25 ± 1°C and 90 to 95% relative humidity. All inoculated plants developed crown rot symptoms identical to those observed in the nursery 2 months after inoculation. Control plants remained symptomless. C. pauciramosum was always reisolated from the infected plants and identified as previously described. C. pauciramosum was previously detected in Italy as being responsible for a leaf spot on M. hypericifolia (3). To our knowledge, this is the first record in the world of crown rot of scarlet honey myrtle caused by C. pauciramosum. References: (1) P. W. Crous. Taxonomy and Pathology of Cylindrocladium (Calonectria) and Allied Genera. The American Phytopathological Society, St. Paul MN, 2002. (2) F. Nigro et al. J. Plant Pathol. 88:S22, 2006. (3) G. Polizzi and P. W. Crous. Eur. J. Plant Pathol. 105:407, 1999.

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First Report of Leaf Spot Caused by Cylindrocladium pauciramosum on Dwarf Willow Myrtle in Italy

Plant Disease ◽

10.1094/pdis-94-2-0274c ◽

2010 ◽

Vol 94 (2) ◽

pp. 274-274 ◽

Cited By ~ 2

Author(s):

G. Polizzi ◽

D. Aiello ◽

G. Parlavecchio ◽

A. Vitale ◽

F. Nigro

Keyword(s):

Leaf Spot ◽

Morphological Characteristics ◽

Intergenic Spacer ◽

First Record ◽

Morphological Characters ◽

Leaf Spot Disease ◽

Centraalbureau Voor ◽

Potted Plants ◽

Leaf Spots ◽

Plant Pathol

Dwarf willow myrtle (Agonis flexuosa (Willd.) Sweet) cv. Nana, an evergreen ornamental shrub belonging to the Myrtaceae, is grown in Italy as an ornamental potted plant. In November 2008, a widespread new leaf spot disease was noticed on ~80% of 5,000 6-month-old potted plants. Plants were obtained from cuttings and produced by a commercial nursery in Catania Province. Symptomatic leaves showed minute, reddish brown spots that enlarged (3 to 5 mm in diameter) and then darkened, presenting a necrotic center defined by a dark purple halo. Leaf spots were surface disinfested with 0.8% NaOCl and plated on potato dextrose agar. Twenty isolates of the fungus that was consistently isolated from the spots were selected and cultured for 8 days at 25°C on carnation leaf agar (CLA). Macroconidiophores consisted of a stipe, a penicillate arrangement of fertile branches, and stipe extension terminating in an obpyriform to ellipsoidal vesicle (6 to 10 μm in diameter). Cylindrical conidia were rounded at both ends, straight, one-septate, and ranged from 44 to 60 × 4 to 5 μm. The fungus was tentatively identified as Cylindrocladium pauciramosum based on these morphological characteristics (2). All single-conidium isolates were mated with tester strains of Calonectria pauciramosa C. L. Schoch & Crous, telomorph of C. pauciramosum, on CLA and produced fertile perithecia (4). Perithecia were solitary or in groups, orange to red-brown, subglobose to ovoid, and ranged from 280 to 400 μm long × 180 to 290 μm in diameter. Further confirmation of species was obtained by amplification and sequencing of the intergenic spacer (IGS) region of rDNA, using M13 Forward (-20) and M13 Reverse primers. On the basis of the complete IGS sequence, two primer sets (218F/218R and 106F/106R) were designed and successfully used in a nested-PCR protocol for the detection of C. pauciramosum from tissues of infected plants (3). On the basis of the combination of morphological characters, mating type, and molecular data, the isolates were identified as C. pauciramosum C.L. Schoch & Crous. One representative isolate (DISTEF-Af1) was deposited at Centraalbureau voor Schimmelcultures open fungi collection (Fungal Biodiversity Centre, Utrecht, the Netherlands; CBS 124659). Pathogenicity tests were performed by adding sterile water to CLA cultures of C. pauciramosum from a single-conidium isolate (DISTEF-Af1) and spraying the resulting spore suspension (105 conidia per ml) on the leaf surface of 20 6-month-old A. flexuosa cv. Nana potted plants. The same number of plants served as noninoculated controls. Following inoculation, plants were kept in plastic bags in a growth chamber at 25 ± 1°C. All inoculated plants developed circular, brown leaf spots identical to those observed in the nursery 5 to 7 days after inoculation. Control plants remained symptomless. C. pauciramosum was always reisolated from the infected plants and identified as previously described. Leaf spotting in seedlings of A. flexuosa was previously associated with infections by C. scoparium in Australia (1). To our knowledge, this is the first record in the world of leaf spots caused by C. pauciramosum on A. flexuosa. References: (1) A. L. Bertus. Agric. Gaz. N. S. W. 87:22, 1976. (2) P. W. Crous. Taxonomy and Pathology of Cylindrocladium (Calonectria) and Allied Genera. The American Phytopathological Society, St. Paul MN, 2002. (3) F. Nigro et al. J. Plant Pathol. 88:S22, 2006. (4) G. Polizzi and P. W. Crous. Eur. J. Plant Pathol. 105:407, 1999.

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Severe Outbreak of Crown Rot and Root Rot Caused by Cylindrocladium pauciramosum on Strawberry Tree in Italy

Plant Disease ◽

10.1094/pdis-93-8-0842b ◽

2009 ◽

Vol 93 (8) ◽

pp. 842-842 ◽

Cited By ~ 7

Author(s):

A. Vitale ◽

D. Aiello ◽

I. Castello ◽

M. A. Dimartino ◽

G. Parlavecchio ◽

...

Keyword(s):

Root Rot ◽

Soil Surface ◽

First Record ◽

Crown Rot ◽

Limiting Factor ◽

Centraalbureau Voor ◽

Potted Plants ◽

Leaf Spots ◽

Strawberry Tree ◽

Crown And Root Rot

From 2006 to 2009, a new disease was noticed in several commercial nurseries in Sicily (Italy) on ~13,000 potted plants of strawberry tree (Arbutus unedo L.) ranging from 3 months to 4 years old. Symptomatic plants showed a crown and root rot and internal brown discoloration of the basal stem. No leaf spots were detected. The percentage of symptomatic plants was variable in the different stocks (1 to 28%). A Cylindrocladium sp. was isolated consistently from symptomatic tissues on potato dextrose agar (PDA). Although many crown rots are caused by Phytophthora or Rhizoctonia spp., plating small pieces of diseased tissue from rotten roots and crowns onto corn meal agar or PDA yielded these pathogens sporadically. Twenty Cylindrocladium isolates obtained from infected basal stems, crowns, and roots were selected and subsequently cultured on carnation leaf agar (CLA). Macroconidiophores consisted of a stipe, a penicillate arrangement of fertile branches, and stipe extension terminating in an obpyriform-to-ellipsoidal vesicle (6 to 10 μm in diameter). Conidia cylindrical, straight, and 1-septate ranged from 40 to 60 × 4 to 5 μm. All single-conidial isolates were mated with tester strains DISTEF-G87 (MAT1-1) and DISTEF-G128 (MAT1-2) of Cylindrocladium pauciramosum (3) on CLA and produced fertile perithecia after 2 months. Perithecia were solitary or in groups, orange to red-brown, subglobose to ovoid, and ranged from 260 to 400 × 180 to 290 μm in diameter. On the basis of the combination of morphological and perithecial characters and mating type the isolates were identified as C. pauciramosum C.L. Schoch & Crous, teleomorph Calonectria pauciramosa C.L. Schoch & Crous (1,4). One representative isolate was deposited at Centraalbureau voor Schimmelcultures (CBS; No. 123918) open fungi collection. Pathogenicity tests were performed by adding sterile water to CLA cultures of C. pauciramosum from a single-conidial isolate and incorporating the resulting spore suspension (105 conidia per ml) on the soil surface of 20 3-month-old strawberry tree potted plants. The same number of plants served as a control. After inoculation, plants were maintained in a growth chamber at 25 ± 1°C and 90 to 95% relative humidity. All inoculated plants developed crown and root rot identical to one observed in the nursery 2 months after inoculation. Control plants remained symptomless. C. pauciramosum was always reisolated from infected plants. This fungus represents a serious threat for ornamental nurseries in Europe. Diseases related to infection of C. pauciramosum are different in relationship to the host tissues and the affected species. On strawberry tree, C. pauciramosum was previously detected in Italy as causal agent of leaf spots (2). To our knowledge, this is the first record of crown and root rot of strawberry tree caused by C. pauciramosum. In contrast with leaf spots, this report could indicate an important limiting factor for cultivation of strawberry tree potted plants in nurseries. The knowledge of the susceptibility of this host to crown and root rot caused by C. pauciramosum can help growers apply specific control strategies in nurseries. References: (1) P. W. Crous. Taxonomy and Pathology of Cylindrocladium (Calonectria) and Allied Genera. The American Phytopathological Society, St. Paul, MN, 2002. (2) G. Polizzi and V. Catara. Plant Dis. 85:803, 2001. (3) G. Polizzi and P. W. Crous. Eur. J. Plant Pathol. 105:407, 1999. (4) C. L. Schoch et al. Plant Dis. 85:941, 2001.

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First Record of Crown and Root Rot Caused by Cylindrocladium pauciramosum on California Lilac in Italy

Plant Disease ◽

10.1094/pd-90-1459b ◽

2006 ◽

Vol 90 (11) ◽

pp. 1459-1459 ◽

Cited By ~ 8

Author(s):

G. Polizzi ◽

A. Vitale ◽

D. Aiello ◽

G. Parlavecchio

Keyword(s):

Root Rot ◽

First Record ◽

Selective Medium ◽

Crown Rot ◽

Stem Rot ◽

Single Spore ◽

Centraalbureau Voor ◽

Basal Stem Rot ◽

Plant Pathol ◽

Stem Lesions

California lilacs, or Ceanothus, are evergreen, drought tolerant, colorful ornamental shrubs belonging to the Rhamnaceae family. Ceanothus thyrsiflorus var. repens is the most common species grown in Italy. In October 2005, a severe wilting was noticed on approximately 3,000 potted, 6-month-old plants obtained from cuttings produced by a commercial nursery in Lecco Province (northern Italy). Wilting was always associated with root rot and brown discoloration at the base of the stem. No leaf spots or stem lesions were detected. A Cylindrocladium sp. was isolated consistently from crown, basal stems, and roots of symptomatic plants with potato dextrose agar. Although many crown rots are caused by Phytophthora spp., this pathogen was not found associated with rotten roots and crown plating small pieces of diseased root tissue and crowns onto selective medium. A random selection of five Cylindrocladium sp. isolates was obtained from the infected crown and basal stem. Subsequently, they were identified on carnation leaf agar (CLA) as Cylindrocladium pauciramosum C.L. Schoch & Crous on the basis of their obpyriform to broadly ellipsoidal terminal vesicles, conidiophore branching pattern, conidium, and perithecial morphology, as well as mating type with tester strains of C. pauciramosum selected isolates (1,4). All single-conidial isolates were mated with tester strains DISTEF-G87 (MAT1-1) and DISTEF-G128 (MAT1-2) of C. pauciramosum on CLA, which confirmed both mating types to be present. Two of the isolates were deposited at Fungal Biodiversity Centre, Centraalbureau voor Schimmelcultures (CBS-120145 and CBS-120146). Pathogenicity tests were performed by macerating CLA cultures of C. pauciramosum, obtained from a single-spore isolate and incorporating them on the soil surface of 20 8-month-old C. thyrsiflorus var. repens potted plants. The same number of plants was used as the control. Following inoculation, plants were well irrigated and kept in a growth chamber at 25 ± 1°C. All inoculated plants developed crown rot, basal stem rot, and root rot 25 days after inoculation. Uninoculated control plants remained healthy. C. pauciramosum was reisolated from the artificially inoculated plants. C. pauciramosum causes considerable damage to the ornamental industry in Italy, where projects have been carried out since the first record of the fungus in Europe (3). C. pauciramosum was previously detected on Ceanothus sp. in the United Kingdom (2), where foliar and stem lesions were described. To our knowledge, this is the first record of the pathogen on C. thyrsiflorus var. repens and the first report of wilting due to crown and basal stem rot. References: (1) P. W. Crous. Taxonomy and Pathology of Cylindrocladium (Calonectria) and Allied Genera. The American Phytopathological Society, St. Paul MN, 2002. (2) C. R. Lane et al. Plant Pathol. 55:582, 2006. (3) G. Polizzi and P. W. Crous. Eur. J. Plant Pathol. 105, 407, 1999. (4) C. L. Schoch et al. Plant Dis. 85:941, 2001.

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A new species of the genus Lucasioides Kwon, 1993 (Isopoda, Oniscidea, Agnaridae) from Siberia, Russia

Zootaxa ◽

10.11646/zootaxa.4903.1.9 ◽

2021 ◽

Vol 4903 (1) ◽

pp. 140-150

Author(s):

KONSTANTIN B. GONGALSKY ◽

PAVEL S. NEFEDIEV ◽

ILYA S. TURBANOV

Keyword(s):

Phylogenetic Analysis ◽

New Species ◽

First Record ◽

Morphological Characters ◽

Molecular Data ◽

Altai Mountains ◽

The Family ◽

Southwestern Siberia ◽

A New Species ◽

Preliminary Phylogenetic Analysis

A new species of the family Agnaridae, Lucasioides altaicus sp. nov., is described from the Altai Mountains, southwestern Siberia, based both on morphological characters and molecular data. This species is the first record of Lucasioides from Russia, whose location is the northernmost habitat of terrestrial isopods in indigenous habitats presently known to Eurasia. The diagnostic characters of the new species and a preliminary phylogenetic analysis within Agnaridae are provided.

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First Report of a Root and Crown Rot Disease of Myrtle in California Caused by Cylindrocladium pauciramosum

Plant Disease ◽

10.1094/pdis.2001.85.4.448c ◽

2001 ◽

Vol 85 (4) ◽

pp. 448-448 ◽

Cited By ~ 3

Author(s):

S. T. Koike ◽

P. W. Crous

Keyword(s):

Species Complex ◽

The United States ◽

Crown Rot ◽

Conidial Suspension ◽

First Report ◽

Potted Plants ◽

Crown Tissue ◽

Root And Crown Rot ◽

Plant Pathol ◽

Rot Disease

Myrtle (Myrtus communis) is a woody, evergreen plant used in California as a landscape shrub or potted plant. In 2000, a new root and crown disease was found in commercial nursery myrtle being grown as potted plants. Roots were necrotic and crown tissue was brown. Affected plants became gray-green in color, withered, and died. A Cylindrocladium sp. was consistently isolated from roots, crowns, and lower stems of symptomatic plants. Isolates were characterized by having penicillate conidiophores terminating in obpyriform to broadly ellipsoidal vesicles. Conidia were hyaline, 1-septate, straight with rounded ends, (50-) 53 to 56 (-58) × (3.5-) 4 to 6 μm, placing it in the Cylindrocladium candelabrum Viégas species complex. Single-conidial isolates (STE-U 4012 to 4018) produced perithecia with viable progeny of Calonectria pauciramosa C.L. Schoch & Crous when mated on carnation leaf agar with tester strains of Cylindrocladium pauciramosum C.L. Schoch & Crous (2). Matings with tester strains of all other species in this complex proved unsuccessful. Only one mating type of C. pauciramosum has thus far been found in the United States. Pathogenicity of representative isolates was confirmed by applying 5 ml of a conidial suspension (1.0 × 106 conidia/ml) to the crowns of potted, 5-month-old, rooted mytle cuttings that were subsequently maintained in a greenhouse (23 to 25°C). After 4 weeks, plant crowns and roots developed symptoms similar to those observed in the nursery, and plants later wilted and died. C. pauciramosum was re-isolated from all plants. Control plants, which were treated with water, did not develop any symptoms. The tests were repeated and the results were similar. This is the first report of C. pauciramosum as a pathogen of myrtle in California. The disease has been reported on myrtle in Europe (1). References: (1) G. Polizzi and P. W. Crous. Eur. J. Plant Pathol. 105:407, 1999. (2) C. L. Schoch et al. Mycologia 91:286, 1999.

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A new species of the genus Kodaianellissus Wang, Bourgoin & Zhang (Hemiptera: Issidae) with morphological and molecular data

Zootaxa ◽

10.11646/zootaxa.4731.2.6 ◽

2020 ◽

Vol 4731 (2) ◽

pp. 270-274

Author(s):

KAMRAN SOHAIL ◽

WEIJIAN HUANG ◽

YALIN ZHANG

Keyword(s):

New Species ◽

Molecular Analysis ◽

Male Genitalia ◽

First Record ◽

Morphological Characters ◽

Molecular Data ◽

Morphological And Molecular Data ◽

A New Species

Kodaianellissus gibbusis sp. nov. is described from Rawlakot, Azad Jammu & Kashmir (Pakistan), which is first record of the genus Kodaianellissus Wang, Bourgoin & Zhang, 2017 from the country. Morphological characters including male genitalia structure are described and illustrated. A checklist and key to all species of Kodaianellissus are provided. A molecular analysis with morphological characters indicates its placement into the Kodaianellissus.

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Multivariate ratio analysis and DNA markers reveal a new Australian species and three synonymies in eucalypt-gall-associated Megastigmus (Hymenoptera: Megastigmidae)

Bulletin of Entomological Research ◽

10.1017/s000748532000022x ◽

2020 ◽

Vol 110 (6) ◽

pp. 709-724 ◽

Cited By ~ 2

Author(s):

Ngoc Hoan Le ◽

Helen F. Nahrung ◽

Jess A. T. Morgan ◽

Simon A. Lawson

Keyword(s):

Species Delimitation ◽

Size Variation ◽

First Record ◽

Morphological Characters ◽

Molecular Data ◽

Species Discrimination ◽

Ratio Analysis ◽

Body Parts ◽

Diagnostic Characters ◽

Taxonomic Decision

AbstractThe genus Megastigmus Dalman, 1820 (Hymenoptera: Megastigmidae) contains potential biocontrol agents of the invasive eucalypt galling chalcid Leptocybe spp. (Hymenoptera: Eulophidae), with several species reported in various parts of the world. Species discrimination is challenging due to intraspecific morphological variation, difficulty in measuring sizes of body parts, and the lack of information regarding the global distribution of parasitic Megastigmus. We used two species commonly associated with Leptocybe in its native range to review taxonomic methods and determine the most reliable morphological characters in species delimitation. We examined size variation of body characters, and conducted species discrimination using multivariate ratio analysis, mitochondrial Cytochrome c oxidase subunit 1 (COI) and nuclear 28S rDNA (28S) sequences. Morphological traits were effective in species delimitation yet revealed high variation in several characters employed in current keys. Knowledge generated on morphology and DNA justified the description of a new species, M. manonae, sp. n., the first record of M. pretorianensis in Australia, and revised diagnostic characters for M. zvimendeli. Based on these diagnostic characters and molecular data, we synonymize three species (M. judikingae, syn. n., from Australia, M. sichuanensis, syn. n., from China and M. icipeensis, syn. n., from Kenya) with M. zvimendeli. Our findings highlight the importance of molecular markers in assisting taxonomic decision-making and the need for coordinated work in identifying Megastigmus associated with Leptocybe spp.

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First record of the genus Parasitorhabditis Fuchs, 1937 (Rhabditida, Nematoda) from Iran with notes on morphological and molecular characters of the Iranian population of P. obtusa (Fuchs, 1915) Chitwood & Chitwood, 1950

Zootaxa ◽

10.11646/zootaxa.4353.3.13 ◽

2017 ◽

Vol 4353 (3) ◽

pp. 591

Author(s):

AHMAD VALIZADEH ◽

SHILA GOLDASTEH ◽

ZAHRA RAFIEI-KARAHROODI ◽

MAJID PEDRAM

Keyword(s):

Bark Beetles ◽

Nematode Species ◽

First Record ◽

Morphological Characters ◽

Molecular Data ◽

The Body ◽

Bayesian Posterior Probability ◽

Molecular Phylogenetic ◽

Morphological And Molecular Data ◽

Mediterranean Pine

Parasitorhabditis obtusa is reported from Iran for the first time. The studied population is characterised with its morphological and molecular data. Morphological characters of the recovered population is in agreement with the currently available data of the species. In molecular phylogenetic studies using partial sequences of 28S rDNA D2/D3 fragment, the species formed a clade with two other isolates of the species with maximal Bayesian posterior probability (1.00) and maximum likelihood bootstrap values (100). The species was in association with bark samples of dead coniferous trees having galleries of bark beetles. It was also recovered from inside of the body of the Mediterranean pine beetle, Orthotomicus erosus, representing a new insect host for this nematode species.

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Phylogeny of the Proteaceae based on atpB and atpB-rbcL intergenic spacer region sequences

Australian Systematic Botany ◽

10.1071/sb98027 ◽

1998 ◽

Vol 11 (4) ◽

pp. 301 ◽

Cited By ~ 73

Author(s):

Sara B. Hoot ◽

Andrew W. Douglas

Keyword(s):

Chromosome Doubling ◽

Intergenic Spacer ◽

Sister Group ◽

Morphological Characters ◽

Molecular Data ◽

Homogeneity Test ◽

Nucleotide Substitutions ◽

Data Set ◽

Intergenic Spacer Region ◽

Pollen Presentation

Parsimony analyses were conducted for 46 genera representing all subfamilies and tribes within Proteaceae using two chloroplast sequences: the gene atpB and the noncoding spacer region between atpB and rbcL. The spacer region was more variable than atpB and provided insertion and deletion data as well as nucleotide substitutions. The atpB and spacer region data sets were highly congruent (as indicated by the partition homogeneity test) and were analysed separately and combined. Both unweighted and weighted character states (3 : 1 correction for transition bias) for the atpB data resulted in very similar strict consensus trees. In addition, the large subfamilies Proteoideae and Grevilleoideae were analysed separately, using appropriate outgroups determined by the analyses with complete sampling. The results from the combination of data were better resolved and supported than the results from each separate data set, although the Grevilleoideae were highly unresolved in all analyses. Most subfamilies in the Proteaceae were essentially monophyletic, but most tribes and subtribes were not. Bellendena is weakly supported as the sister group to all remaining members of the Proteaceae. Monotypic Eidotheoideae is well supported as a member of Proteoideae. Carnarvonioideae and Sphalmioideae are strongly supported as closely allied to the Grevilleoideae, but their positions in relation to this subfamily are unresolved. Other unusual alliances supported by our molecular data are: Isopogon–Adenanthos–Leucadendron–Protea, Petrophile–Aulax, Cardwellia–Euplassa–Gevuina, and Opisthiolepis–Buckinghamia–Grevillea. The tree resulting from the combined data showed limited congruence with morphological characters (flower pairs, stylar pollen presentation, and ovule number). Congruence with chromosome number was minimal, but our tree does support previous hypotheses of multiple aneuploidy and chromosome doubling events. The African and South American genera included in our analysis are dispersed among various clades with taxa from Australia and Asia, suggesting a former Gondwanian distribution for Proteaceae.

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First Report of Aspergillus Vine Canker on Table Grapes Caused by Aspergillus niger in Europe

Plant Disease ◽

10.1094/pdis-92-10-1471b ◽

2008 ◽

Vol 92 (10) ◽

pp. 1471-1471 ◽

Cited By ~ 3

Author(s):

A. Vitale ◽

I. Castello ◽

G. Polizzi

Keyword(s):

Aspergillus Niger ◽

Shoot Growth ◽

Disease Incidence ◽

First Record ◽

Control Treatment ◽

Branch Points ◽

Centraalbureau Voor ◽

Potted Plants ◽

Table Grapes ◽

Bunch Rot

In March of 2003, vine cankers and lesions were first observed on vigorous 1-year-old cv. Black Rose vines (Vitis vinifera) in a vineyard in southeastern Sicily, Italy. Since then, the same symptoms have been observed every year up to 2007 throughout the most important table grape production areas of Italy on cvs. Black Rose, Redglobe, and Italia. The disease epidemic has increased during the last 2 years, with incidence of cankered vines as much as 12.5%, and with two to three canker lesions per infected vine. On affected vines, most cankers were found at branch points and on the stems of young shoots grafted in the field. The infections seem to start from growth cracks on rapidly growing 1-year-old shoots or through wounds caused by the removal of lateral shoots. First symptoms usually appeared in late July or August as reddish pinhead-size drops of sap exuded from the infection site on the surface. By October to November, trunks of affected vines were girdled by the canker and prematurely displayed bright fall colors. The trunk appeared slightly larger and spongy where the canker occurred. Internally, cankered tissues were discolored and dead, and black powdery spores were abundant and sometimes visible on the surface. Callous tissue was often associated with the canker. Canker length was variable (average of approximately 8 cm) and either affected a small portion of the shoot's cross section or girdled it completely. Cultures of the fungus isolated from canker lesions or from the black spores within the lesions consistently yielded colonies typical of Aspergillus niger van Tiegh (3) when cultured on potato dextrose agar (PDA) supplemented with 100 μg/ml of chloramphenicol. Pathogenicity tests were carried out on potted plants of cvs. Black Rose, Redglobe, and Italia grown in a greenhouse by inoculating six vigorous, young grapevines of each cultivar. Inoculations were made by placing 8-mm-diameter mycelial plugs taken from actively growing cultures of A. niger on a cut made by removal of a lateral shoot with a sterile razor. Inoculated sites were sealed with Parafilm to prevent dehydration of the inoculum. For a control treatment, an equal number of grapevines was inoculated with only a PDA plug. Three months later, all inoculated grapevines exhibited symptoms similar to those observed in the commercial vineyards while control vines remained symptomless. A. niger was always reisolated on PDA media from all infected vines. A. niger is reported to cause bunch rot complex of grape (1,2) and was previously reported in California causing Aspergillus vine canker (4). Since disease incidence and severity can increase year after year on vines grafted in the field, it is recommended that all cankers be removed by cutting back the vines in the fall. In the following March to April, growers could revisit the affected vines, evaluate shoot growth, and vines with weak shoot growth should be cut back below the canker. Subsequently, the vine can be retrained using a shoot originating from below the canker. To our knowledge, this is the first record of Aspergillus vine canker caused by A. niger on table grapes in Europe. References: (1) W. B. Hewitt. Compendium of Grape Diseases. R. C. Pearson and A. C. Gohen, eds. The American Phytopathological Society, St. Paul, MN, 1994. (2) W. R. Jarvis and J. A. Traquair. Plant Dis. 68:718, 1984. (3) M. A. Klich. Identification of Common Aspergillus Species. Centraalbureau voor Schimmelcultures, Utrecht, The Netherlands, 2002. (4) T. J. Michailides. Plant Dis. 86:75, 2002.

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