Genetic Diversity and Pathogenicity of Botryosphaeriaceae Species Associated with Symptomatic Citrus Plants in Europe

This study represents the first survey studying the occurrence, genetic diversity, and pathogenicity of Botryosphaeriaceae species associated with symptomatic citrus species in citrus-production areas in five European countries. Based on morphological features and phylogenetic analyses of internal transcribed spacer (ITS) of nuclear ribosomal DNA (nrDNA), translation elongation factor 1-alpha (TEF1) and β-tubulin (TUB2) genes, nine species were identified as belonging to the genera Diplodia, Dothiorella, Lasiodiplodia, and Neofusicoccum. Isolates of Neofusicoccum parvum and Diplodia pseudoseriata were the most frequently detected, while Dothiorella viticola had the widest distribution, occurring in four of the five countries sampled. Representative isolates of the nine Botryosphaeriaceae species used in the pathogenicity tests caused similar symptoms to those observed in nature. Isolates assayed were all re-isolated, thereby fulfilling Koch’s postulates. Isolates of Diplodia pseudoseriata and Diplodia olivarum are recorded for the first time on citrus and all species found in our study, except N. parvum, are reported for the first time on citrus in Europe.

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Spegazzinia camelliae sp. nov. (Didymosphaeriaceae, Pleosprales), a new endophytic fungus from northern Thailand

Phytotaxa ◽

10.11646/phytotaxa.483.2.4 ◽

2021 ◽

Vol 483 (2) ◽

pp. 117-128

Author(s):

NAKARIN SUWANNARACH ◽

JATURONG KUMLA ◽

SAISAMORN LUMYONG

Keyword(s):

Phylogenetic Analyses ◽

Large Subunit ◽

Elongation Factor ◽

Small Subunit ◽

Internal Transcribed Spacers ◽

Nuclear Ribosomal Dna ◽

Full Description ◽

Translation Elongation ◽

Spine Length ◽

Elongation Factor 1 Alpha

A new endophytic ascomycete, described herein as Spegazzinia camelliae, was isolated from leaves of Camellia sinensis var. assamica collected from Nan Province, Thailand. This species is characterized by basauxic conidiophores and dark brown to blackish brown α and β conidia. It can be distinguished from previously described Spegazzinia species by the spine length of the α conidia and the size of the β conidia. Multi-gene phylogenetic analyses of the small subunit (SSU), large subunit (LSU) and internal transcribed spacers (ITS) of the nuclear ribosomal DNA (rDNA) and the translation elongation factor 1-alpha (tef1) genes also support S. camelliae is a distinct new species within Spegazzinia. A full description, color photographs, illustrations and a phylogenetic tree showing the position of S. camelliae are provided.

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Identification and Pathogenicity of Fungal Species Associated with Canker Diseases of Pistachio in California

Plant Disease ◽

10.1094/pdis-10-18-1717-re ◽

2019 ◽

Vol 103 (9) ◽

pp. 2397-2411 ◽

Cited By ~ 6

Author(s):

Mohamed T. Nouri ◽

Daniel P. Lawrence ◽

Leslie A. Holland ◽

David A. Doll ◽

Craig E. Kallsen ◽

...

Keyword(s):

Phylogenetic Analyses ◽

Schizophyllum Commune ◽

Elongation Factor ◽

Fungal Species ◽

Elongation Factor 1Α ◽

Translation Elongation ◽

Brown Discoloration ◽

Pathogenicity Tests ◽

Branch Dieback ◽

Translation Elongation Factor 1Α

A survey was conducted during 2015 and 2016 in pistachio orchards throughout the San Joaquin Valley of California to investigate the occurrence of canker diseases and identify the pathogens involved. Cankers and dieback symptoms were observed mainly in orchards aged >15 years. Symptoms of canker diseases included brown to dark brown discoloration of vascular tissues, wood necrosis, and branch dieback. In total, 58 fungal isolates were obtained from cankers and identified based on multilocus phylogenetic analyses (internal transcribed spacer, glyceraldehyde 3-phosphate dehydrogenase, β-tubulin, calmodulin, actin 1, and translation elongation factor 1α) representing 11 fungal species: Colletotrichum karstii, Cytospora californica, Cytospora joaquinensis, Cytospora parapistaciae, Cytospora pistaciae, Diaporthe ambigua, Didymella glomerata, Diplodia mutila, Neofusicoccum mediterraneum, Phaeoacremonium canadense, and Schizophyllum commune. Pathogenicity tests conducted in the main pistachio cultivars Kerman, Golden Hills, and Lost Hills using the mycelium-plug method indicated that all fungal species were pathogenic to Pistacia vera. All species tested caused cankers in pistachio branches, although virulence among species varied from high to moderate. Overall, N. mediterraneum and Cytospora spp. were the most widespread and virulent species associated with canker diseases of pistachio in California.

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Genetic Diversity and Aggressiveness of Fusarium spp. Isolated from Canola in Alberta, Canada

Plant Disease ◽

10.1094/pdis-01-13-0061-re ◽

2014 ◽

Vol 98 (6) ◽

pp. 727-738 ◽

Cited By ~ 11

Author(s):

Yongyan Chen ◽

Qixing Zhou ◽

Stephen E. Strelkov ◽

Sheau-Fang Hwang

Keyword(s):

Sequence Data ◽

Phylogenetic Analyses ◽

Geographic Origin ◽

Elongation Factor ◽

Morphological Characteristics ◽

Seedling Blight ◽

Fusarium Spp ◽

Translation Elongation ◽

Fusarium Seedling Blight ◽

Pathogenicity Tests

Canola (Brassica napus) is one of the most economically important oilseed crops in Canada. Fusarium seedling blight is a root disease with the potential to cause severe yield reductions in canola. Fusarium spp. are commonly isolated root pathogens from fields in Alberta. Fusarium infection can also cause root rot in adult plants. In this study, 128 isolates identified as Fusarium spp. were recovered from field soils in central Alberta and from the roots of diseased canola plants with typical Fusarium seedling blight symptoms. Six species of Fusarium were identified, with Fusarium acuminatum as the predominant species (57 of 128 isolates, 44.5%). Phylogenetic analyses based on the translation elongation factor 1-α and the internal transcribed spacer sequence data were used for evaluation of genetic variations, and also used for Fusarium spp. identification in combination with morphological characteristics and polymerase chain reaction-based analyses. Based on disease ratings in pathogenicity tests, six isolates of F. avenaceum showed high aggressiveness on canola. Also, the aggressiveness varied within all Fusarium spp. No correlation was observed between aggressiveness and the geographic origin of the isolates.

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Pestalotiopsis-Like Species Causing Gray Blight Disease on Camellia sinensis in China

Plant Disease ◽

10.1094/pdis-05-17-0642-re ◽

2018 ◽

Vol 102 (1) ◽

pp. 98-106 ◽

Cited By ~ 14

Author(s):

Yingjuan Chen ◽

Liang Zeng ◽

Na Shu ◽

Maoyuan Jiang ◽

Han Wang ◽

...

Keyword(s):

Camellia Sinensis ◽

Phylogenetic Analyses ◽

Elongation Factor ◽

Tea Plant ◽

Translation Elongation ◽

Phylogenetic Grouping ◽

Pathogenicity Tests ◽

High Bootstrap ◽

Blight Disease ◽

Elongation Factor 1

Gray blight of tea, caused by several Pestalotiopsis-like species, is one of the most destructive foliar diseases in tea cultivation yet the characteristics of these pathogens have not been confirmed until now. With morphological and multigene phylogenetic analyses, we have identified the gray blight fungi as Pseudopestalotiopsis camelliae-sinensis, Neopestalotiopsis clavispora, and Pestalotiopsis camelliae. Phylogenetic analyses derived from the combined internal transcribed spacer, β-tubulin, and translation elongation factor 1-α gene regions successfully resolved most of the Pestalotiopsis-like species used in this study with high bootstrap supports and revealed three major clusters representing these three species. Differences in colony appearance and conidia morphology (shape, size, septation, color and length of median cells, and length and number of apical and basal appendages) were consistent with the phylogenetic grouping. Pathogenicity tests validated that all three species isolated from tea leaves were causal agents of gray blight disease on tea plant (Camellia sinensis). This is the first description of the characteristics of the three species Pseudopestalotiopsis camelliae-sinensis, N. clavispora, and Pestalotiopsis camelliae as causal agents of tea gray blight disease in China.

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Neofusicoccum batangarum Causing Dieback of Mango (Mangifera indica) in Florida

Agriculture ◽

10.3390/agriculture11090853 ◽

2021 ◽

Vol 11 (9) ◽

pp. 853

Author(s):

Alina S. Puig ◽

Mike C. Winterstein

Keyword(s):

Mangifera Indica ◽

Elongation Factor ◽

Molecular Data ◽

Translation Elongation ◽

Causal Organism ◽

Rdna Its ◽

Wide Range ◽

Pathogenicity Tests ◽

Production Areas ◽

Negative Controls

Mango (Mangifera indica) is an economically significant crop, and is affected by dieback in nearly all commercial production areas. Due to the wide range of organisms previously associated with these disease symptoms in Florida, isolations and pathogenicity tests were carried out to determine the causal organism. The pathogen was identified as Neofusicoccum batangarum based on genetic sequences from three loci (internal transcribed spacer of the rDNA (ITS), β-tubulin (BT), and translation elongation factor 1-α (EF)), recommended for members of the Botryosphaeriaceae family. Possible infection routes were determined by inoculating wounded and unwounded stems with N. batangarum. Trees wounded prior to pathogen inoculation developed larger lesions (5.85 cm ± 1.51) than unwounded trees (0.51 cm ± 0.48), p < 0.0003. In addition, lesions only developed at a small number of inoculation sites in the absence of wounds (14.3%), compared to 93% when stems were wounded. No necrosis was observed in the negative controls. This study provides molecular data on N. batangarum, and evidence of its role causing mango dieback in Florida.

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New species of Nectria and Thyronectria from Xinjiang, China

Phytotaxa ◽

10.11646/phytotaxa.433.4.1 ◽

2020 ◽

Vol 433 (4) ◽

pp. 253-264

Author(s):

RONG MA ◽

SHENG-NAN LI ◽

YING ZHAO ◽

MIN WANG ◽

THEMIS J. MICHAILIDES ◽

...

Keyword(s):

Ribosomal Rna ◽

Sequence Data ◽

Phylogenetic Analyses ◽

Elongation Factor ◽

Translation Elongation Factor ◽

Translation Elongation ◽

Elongation Factor 1 Alpha ◽

Alpha Actin ◽

First Time ◽

Elongation Factor 1

Nectria berberidis sp. nov. and Thyronectria berberidicola sp. nov. isolated from Berberis heteropoda in Xinjiang Uygur Autonomous Region, China, are described and illustrated. Nectria berberidis is characterized by clavate asci (50–87 × 8–12 μm) with ellipsoidal to fusiform, 1-septate ascospores. Thyronectria berberidicola is characterized by clavate asci (117–25.9 × 63.7–117.9 μm) with ellipsoidal to fusiform ascospores that have 5–8 transverse septa and 1(–2) longitudinal septum. Ascospores bud to produce hyaline, bacillar ascoconidia. Phylogenetic analyses based on alpha-actin (ACT), the internal transcribed spacer (ITS), the large nuclear ribosomal RNA subunit (LSU), translation elongation factor 1-alpha (TEF1) and the β-tubulin (TUB) sequence data revealed that isolates of N. berberidis and T. berberidicola form a distinct clade within Nectria and Thyronectria, respectively. In addition, Nectria nigrescens is reported for the first time in China.

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Identification and Detection of Fusarium striatum as a New Record of Pathogen to Greenhouse Tomato in Northeastern America

Plant Disease ◽

10.1094/pdis-08-13-0844-re ◽

2014 ◽

Vol 98 (3) ◽

pp. 292-298 ◽

Cited By ~ 4

Author(s):

Lauriane M. Moine ◽

Caroline Labbé ◽

Gerry Louis-Seize ◽

Keith A. Seifert ◽

Richard R. Bélanger

Keyword(s):

Elongation Factor ◽

Translation Elongation ◽

Disease Symptoms ◽

Tomato Plants ◽

Greenhouse Tomato ◽

Pathogenicity Tests ◽

Fusarium Sp ◽

Polymerase Chain ◽

First Time ◽

Partial Translation

Recently, a new disease was reported on greenhouse tomato plants in both Quebec, Canada and Maine, United States. Symptomatic plants bore brown lesions at graft points and pruning sites, resulting in expanding cankers with clearly delineated margins. Diseased plants eventually wilted and died within a few weeks following the appearance of the first symptoms. The symptoms are reminiscent of infection by Fusarium oxysporum f. sp. radicis-lycopersici, with the notable difference of a discoloration of the pith area rather than the vascular tissues. A homothallic Fusarium sp. was consistently recovered from these lesions. Sequencing of the internal transcribed spacer and the partial translation elongation factor 1-α gene identified the species as F. striatum. Pathogenicity tests with F. striatum isolates from diseased tissues reproduced disease symptoms in tomato similar to those observed on tomato plants in the greenhouses. Specific detection of F. striatum from mycelia and diseased and disease-free plant tissues was achieved by developing a polymerase chain reaction-based test. These results establish, for the first time, that the species F. striatum is the cause of crown and stem rot affecting tomato in North America. In addition F. striatum was detected from all sampled tissues of plants delivered by the nursery common to both growers, suggesting that the transplants would be the source of the inoculum.

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Dieback of Euonymus alatus (Celastraceae) Caused by Cytospora haidianensis sp. nov. in China

Forests ◽

10.3390/f11050524 ◽

2020 ◽

Vol 11 (5) ◽

pp. 524 ◽

Cited By ~ 1

Author(s):

Xian Zhou ◽

Meng Pan ◽

Haoyu Li ◽

Chengming Tian ◽

Xinlei Fan

Keyword(s):

Rna Polymerase Ii ◽

Phylogenetic Analyses ◽

Economic Value ◽

Carbon Sources ◽

Elongation Factor ◽

Causal Agent ◽

Optimum Growth ◽

Translation Elongation ◽

Euonymus Alatus ◽

Pathogenicity Tests

Euonymus alatus (Celastraceae) is widely cultivated in China for its economic value and landscape benefits. Euonymus alatus dieback occurs due to members of Cytospora and has become one of the most severe diseases affecting its cultivation in China. In this study, we examined the causal agent of bough dieback on campuses of University Road, Beijing, China. Among the strains, three were morphologically consistent with Cytospora, showing hyaline and allantoid conidia. Based on phylogenetic analyses of the concatenated actin (ACT), internal transcribed spacer (ITS), RNA polymerase II second largest subunit (RPB2), translation elongation factor 1-alpha (TEF1-α) and beta-tubulin (TUB2) gene sequences, along with morphological and physiological features, we propose C. haidianensis as a novel species. It was confirmed as a causal agent of dieback of E. alatus by pathogenicity tests. Mycelial growth of Cytospora haidianensis occurred at pH values ranging from 3.0 to 11.0, with optimum growth at 8.3, and at temperatures from 5 to 35 °C, with optimum growth at 19.8 °C. We also tested the growth of C. haidianensis in the presence of six carbon sources. Sucrose, maltose and glucose were highly efficient and xylose was the least. The ability of C. haidianensis to grow at 19.8 °C may help to explain its occurrence causing dieback of E. alatus in Beijing during the autumn season.

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Early Season Symptoms on Stem, Inflorescences and Flowers of Grapevine Associated with Botryosphaeriaceae Species

Plants ◽

10.3390/plants9111427 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1427

Author(s):

Pedro Reis ◽

Ana Gaspar ◽

Artur Alves ◽

Florence Fontaine ◽

Inês Lourenço ◽

...

Keyword(s):

Elongation Factor ◽

Translation Elongation ◽

Early Season ◽

Grapevine Trunk Diseases ◽

Leaf Chlorosis ◽

Central Regions ◽

Botryosphaeria Dieback ◽

Trunk Diseases ◽

Pathogenicity Tests ◽

Botryosphaeriaceae Species

Botryosphaeria dieback caused by several Botryosphaeriaceae species is one of the most important grapevine trunk diseases affecting vineyards worldwide. These fungi cause wedge-shaped perennial cankers and black streaking of the wood and have also been associated with intervein leaf chlorosis, dried or mummified berries, and eventually, the death of the plant. Early season symptoms may sometimes be disregarded by growers, being mistaken with symptoms from other diseases such as downy mildew or botrytis rot. Currently, few studies are available to determine what species may be causing these early season symptoms in grapevines. During the 2018 season, during the flowering period, grapevine samples showing necrosis on green shoots, dried inflorescences, and flowers, were collected in vineyards throughout the central regions of Portugal. Isolations were performed from symptomatic organs, and twenty-three isolates of Botryosphaeriaceae were selected. An analysis of the ITS and part of the translation elongation factor 1-α sequences was performed, revealing that the two main species apparently responsible for these symptoms were Diplodia seriata and Neofusicoccum parvum. In pathogenicity tests conducted on 1-year-old plants grown under controlled conditions in a greenhouse and on field-grown clusters, symptoms were reproduced, confirming the pathogenic behavior of the selection of isolates.

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Multigene Phylogeny and Morphology Reveal Three Novel Species and a Novel Record of Agaricus From Northern Thailand

Frontiers in Microbiology ◽

10.3389/fmicb.2021.650513 ◽

2021 ◽

Vol 12 ◽

Author(s):

Chanyawat Jaichaliaw ◽

Jaturong Kumla ◽

Santhiti Vadthanarat ◽

Nakarin Suwannarach ◽

Saisamorn Lumyong

Keyword(s):

Phylogenetic Trees ◽

Large Subunit ◽

Elongation Factor ◽

Morphological Characteristics ◽

Internal Transcribed Spacers ◽

Nuclear Ribosomal Dna ◽

Translation Elongation ◽

Northern Thailand ◽

Three New Species ◽

First Time

Agaricus is a saprophytic mushroom genus widely distributed throughout the world. In this study, a survey of the Agaricus species carried out around Chiang Mai University in northern Thailand from 2018 to 2019 yielded 12 collections. Morphological characteristics and phylogenic analyses based on the internal transcribed spacers (ITS) and a fragment of the large subunit (LSU) of the nuclear ribosomal DNA (rDNA), and a fragment of the translation elongation factor 1-alpha (tef1) genes were investigated. The results revealed that these collections belong to six species including Agaricus erectosquamosus, Agaricus pallidobrunneus, Agaricus subrufescens, and three new species. Agaricus thailandensis sp. nov. was found to belong to Agaricus sect. Minores, which is placed in Agaricus subg. Minores. Aagricus pseudoerectosquamosus sp. nov. was placed in Agaricus sect. Brunneopicti within Agaricus subg. Pseudochitonia. Furthermore, Agaricus lannaensis remains an incertae sedis in Agaricus subg. Pseudochitonia. Additionally, this study was proposed that A. pallidobrunneus was discovered in Thailand for the first time. Full descriptions, color photographs, illustrations, and phylogenetic trees are provided.

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