First Report of Lasiodiplodia pseudotheobromae Causing Collar Rot of Peanut in Shandong Province, China

In August 2019, a collar rot of peanut was observed in several fields in Qingdao, Shandong province, China. Disease survey was conducted in several peanut fields. Less than 5% plants exhibited various symptoms, including brown or black stem rot, pod rot, leaf chlorotic, wilted, and even dead. Symptomatic stems were cut into small pieces, surface disinfested with 70% ethanol for 1 min, 1% NaClO for 2 minutes, rinsed three times with sterile water, and dried on sterile filter papers. Pieces then were plated on potato dextrose agar (PDA) media and incubated at 25°C in darkness. Fungal cultures were initially white, then turned gray, and eventually turned black, and aerial hyphae were dense, fluffy. Conidia were ellipsoidal, initially hyaline, unicellular, 14.3 to 21.1 × 8.7 to 13.2 µm (n = 50), and mature conidia showed dark brown, with a central septum, and longitudinal stripes. Molecular identification was performed by sequencing ITS with ITS1/ITS4 (White et al., 1990) and beta tubulin gene with Bt2a/Bt2b (Glass and Donaldson, 1995) of a representative isolate ZHX9. ITS and beta tubulin regions (OK427342 and OK489788) of ZHX9 obtained 99.62 and 100% similar to L. pseudotheobromae (KF766193 and EU673111), respectively. Phylogenetic analysis was done using Neighbor-Joining (NJ) analysis based on those gene sequences. The microorganism we have isolated was identified as L. pseudotheobromae based on molecular analysis and morphological characteristics. For pathogenicity assay, twelve ten-days-old peanut (Zhonghua No.12) seedlings were each inoculated with one mycelial plug (8 mm in diameter) by placing the inoculum on the base of the stem. Twelve plants were each inoculated with a plug of non-colonized PDA as controls. Plants were incubated in a growth chamber (30°C in the day and 25°C at night, a 12-h photoperiod and 80% RH). Necrotic lesions were observed on stems of all inoculated seedlings 5 days after inoculation, whereas control plants remained asymptomatic, and L. peudotheobromae was consistently re-isolated from symptomatic stem. In Asia, peanut collar rot caused by L. teudotheobromae has been reported in India, Indonesia, North Vietnam (Nguyen, et al., 2006) and China (Guo, et al., 2014), but collar rot caused by L. pseudotheobromae has not been reported. To our knowledge, this is the first report of L. peudotheobromae causing collar rot on peanut in China. These results will provide crucial information for studying on epidemiology and management of this disease.

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First Report of Chalara fraxinea on Common Ash in Italy

Plant Disease ◽

10.1094/pdis-94-1-0133a ◽

2010 ◽

Vol 94 (1) ◽

pp. 133-133 ◽

Cited By ~ 20

Author(s):

N. Ogris ◽

T. Hauptman ◽

D. Jurc ◽

V. Floreancig ◽

F. Marsich ◽

...

Keyword(s):

Morphological Characteristics ◽

Aluminum Foil ◽

Malt Extract ◽

First Report ◽

Chalara Fraxinea ◽

Ash Trees ◽

Mycelial Plug ◽

Northeastern Italy ◽

Xylem Discoloration ◽

Branch Dieback

In many European countries, the anamorphic Chalara fraxinea Kowalski (teleomorph Hymenoscyphus albidus [Roberge ex Desm.] Phillips; 1–3) is responsible for a severe and rapidly spreading dieback of common ash (Fraxinus excelsior L.) since it was first reported in Poland. Recently, this disease was added to the EPPO Alert List and the NAPPO Phytosanitary Alert System. Symptomatic trees were observed in a 1.8-ha ash-maple forest in northeastern Italy (Fusine, UD; 46°30′N, 13°37′E; 782 m above sea level) along the Italo-Slovenian border in July 2009. Symptoms were found on approximately 10% of mature common ash and 70% of seedlings. Main symptoms were shoot, twig, and branch dieback, wilting, and bark cankers (1). Fungal fruiting bodies were not found on or near the canker surface. Furthermore, longitudinal and radial sections through the cankers revealed gray-to-brown xylem discoloration. One symptomatic 3-year-old plant was randomly selected and from the necrotic margin of one canker previously surface-sterilized with 3% sodium hypochlorite and rinsed, four 2-mm-wide chips were placed on malt extract agar (MEA) and incubated at 21 ± 1°C in the dark. Among a variety of microorganisms, after 19 days, slow-growing colonies (mean radius of 12 mm) appeared that were effuse, cottony, and often fulvous brown but sometimes dull white with occasional gray-to-dark gray patches. The purified isolate was then transferred to the same medium at 4 ± 1°C in the dark, and after 11 days, hyaline-to-dark gray phialides were observed producing numerous conidia in slimy droplets and sometimes in chains. Phialophores measured 8.6 to 21.0 (15.1) μm long (n = 20), 4.2 to 13.4 (8.8) × 3.6 to 5.5 (4.7) μm at the base, and 5.2 to 8.7 (6.5) × 2.5 to 3.1 (2.8) μm at the collarette; conidia measured 2.8 to 4.2 (3.4) × 1.9 to 2.5 (2.2) μm (n = 40); and first formed conidia measured 5.5 to 6.5 (5.9) × 1.8 to 2.5 (2.1) μm (n = 20). These morphological characteristics matched Kowalski's (1) description of C. fraxinea. In August of 2009, the fungal isolate was used to test pathogenicity with current year shoots of 25 6-year-old (150 to 210 cm high) asymptomatic common ash trees under quarantine conditions (Slovenian Forestry Institute's experimental plots). For every plant, the bark of the main shoot (10 to 13 mm in diameter) was wounded with a 6-mm-diameter cork borer. Twenty saplings were inoculated with one 6-mm-diameter mycelial plug obtained from the margin of a 26-day-old culture (MEA), while five saplings were inoculated with sterile MEA plugs. All wounds were sealed with Parafilm and aluminum foil. After 28 days, all plants inoculated with the C. fraxinea showed bark lesions (2 to 39 mm long, mean 7 mm) and wood discoloration (6 to 85 mm long, mean 22 mm) from which the pathogen was reisolated. These symptoms were absent from controls and the pathogen was never reisolated. To our knowledge, this is the first report of C. fraxinea in Italy. Investigations on its presence in all Fraxinus species naturally growing in the investigated area and in the nearest regions are in progress. The obtained isolate is preserved in both Padova and Ljubljana herbaria as CFIT01. References: (1) T. Kowalski. For. Pathol. 36:264, 2006. (2) T. Kowalski and O. Holdenrieder. For. Pathol. 39:1, 2009. (3) T. Kowalski and O. Holdenrieder. For. Pathol. 39:304, 2009.

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First report of the parasitic invasive weed field dodder (Cuscuta campestris) parasitizing the confamilial invasive weed common morning-glory (Ipomoea purpurea) in Shandong, China

Plant Disease ◽

10.1094/pdis-09-20-1934-pdn ◽

2020 ◽

Author(s):

Xiao-Jian Qu ◽

Shou-Jin Fan

Keyword(s):

South America ◽

Morphological Characteristics ◽

Shandong Province ◽

Morning Glory ◽

Molecular Evidence ◽

Accession Number ◽

Invasive Weed ◽

First Report ◽

Ipomoea Purpurea ◽

Cuscuta Campestris

Common morning-glory (Ipomoea purpurea (L.) Roth, Convolvulaceae), an annual herbaceous vine native to South America, was first recorded to be cultivated in China in 1890, and since then it has invaded all provinces of China. It was one of the 18 alien invasive species in China (MEE. 2014). As an invasive weed, it can readily invade dry lands, orchards, and nurseries and compete for sunlight by wrapping other plants. On 20 September 2019 and 18 July 2020, I. purpurea was found to be parasitized by a dodder species (also Convolvulaceae) in Lushan Mountain (36°21′N, 118°3′E, 569 m elevation), Shandong province, China (Fig. S1). Within and area of ca. 100 m2, dozens of individuals of common morning-glory were parasitized by the leafless stems of dodder. After removal of the haustrial connection of the dodder stem from the I. purpurea stem, brownish black lesions around uneven holes were visible on the I. purpurea stem, with broken haustoria clearly visible to our naked eye remaining in the I. purpurea stem (Fig. S1). Anatomical results showed that the haustoria of dodder penetrate I. purpurea stem and xylem elements connect the vascular systems of both the parasitic and host plant (Fig. S1). Based on morphological characteristics of stems, inflorescences, calyx, corolla, stamens, and capsules as described in Costea et al. (2006), this dodder was identified as Cuscuta campestris Yunck. (i.e., field dodder). Field dodder is readily distinguished from C. chinensis and C. australis in China by the capsules with persistent corollas enveloping 1/3 or less of its base and the spreading and inflexed corolla lobes with acute to acuminate apices. In order to further confirm the identity of the species, total genomic DNA was extracted and sequenced using genome-skimming method as described in Qu et al. (2019). An 831-bp region of 18S-ITS1-5.8S-ITS2-26S for the dodder studied was assembled, examined, and deposited in GenBank under accession number MN718805. The new sequence has 100% similarity with other available sequences of C. campestris (accession number: KT383104, KT383150, KY968857). Phylogenetic analysis also placed the new dodder accession with other accessions of C. campestris (Fig. S2a). In addition, the plastome sequence of the dodder studied was assembled (86,727 bp in length) and deposited in GenBank under accession number MN708214, and a BLAST analysis found that it was 99.98% similar to that of C. gronovii (accession number: AM711639). The plastome of C. gronovii was published by Funk et al. (2007). However, Costea et al. (2015) indicated that Funk et al. (2007) misidentified C. campestris as C. gronovii. Furthermore, our phylogenetic tree strongly supported the identification of the dodder studied as C. campestris (Fig. S2b). Therefore, the dodder on common morning-glory in Shandong province was finally identified as C. campestris according to morphological and molecular evidence. The specimen of C. campestris on I. purpurea was deposited at the herbarium of the College of Life Sciences, Shandong Normal University (voucher number: 092012B). Field dodder, the second most common dodder species in North America, is the most widespread Cuscuta weed in the world and has been found in Africa, Asia, Australia, Europe, and South America (Holm et al. 1997). To our knowledge, this is the first report of the parasitic invasive weed C. campestris parasitizing the invasive weed I. purpurea in Shandong of China. This is also the first report of Cuscuta species parasitizing confamilial Ipomoea species, which is especially noteworthy given that the genus Cuscuta is sister to the genus Ipomoea. This study provides a good model for exploring gene flow between species of closely related genera with different lifestyle. Another implication of this study is that customs and departments of inspection and quarantine need to quarantine the seeds or plants of both dodders and common morning-glories.

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First Report of Phytophthora cactorum Causing Root Rot of Processing Carrots (Daucus carota) in Michigan

Plant Disease ◽

10.1094/pdis-91-4-0459b ◽

2007 ◽

Vol 91 (4) ◽

pp. 459-459 ◽

Cited By ~ 1

Author(s):

C. Saude ◽

M. K. Hausbeck ◽

O. Hurtado-Gonzales ◽

C. Rippetoe ◽

K. H. Lamour

Keyword(s):

New York ◽

Tap Water ◽

Morphological Characteristics ◽

Soft Rot ◽

The United States ◽

Rubus Idaeus ◽

Phytophthora Cactorum ◽

Carrot Root ◽

First Report ◽

Mycelial Plug

In the fall of 2005, processing carrot fields in Mason, Newaygo, and Oceana counties, Michigan, were surveyed for Phytophthora spp. Carrot roots were sampled from areas of fields that exhibited patches of chlorotic, blighted, or wilted foliage. Dark brown, firm, water-soaked lesions occurred near the middle and crown areas of diseased carrot roots. In the advanced stages of disease, carrot root tissue readily collapsed and a soft rot developed while petioles turned black. The internal portions of the diseased carrot roots were brown and rubbery. Roots with these symptoms are not suitable for processing. Carrot roots were washed with tap water and the tissue excised from the edge of developing lesions and plated aseptically onto BARP-amended (25 ppm of benomyl, 100 ppm of ampicillin, 30 ppm of rifampicin, and 100 ppm of pentachloronitrobenzene) regular V8 juice agar. Plates were incubated at 23 to 25°C for 7 days. Phytophthora sp. was isolated from carrot root samples from all surveyed areas. Ten representative single-sporangium isolates cultured on dilute V8 juice agar were examined for morphological characteristics. The homothallic Phytophthora sp. isolates produced papillate, obpyriform, caducous sporangia (35.0 to 45.2 × 26.2 to 33.2 μm) with 1 to 3 μm long pedicels, plerotic oospores (27.0 to 32.0 μm in diameter) with paragynous antheridia, and primarily terminally produced chlamydospores that were 30.0 to 40.0 μm in diameter. Radial growth on V8 juice agar was observed at temperatures between 10 and 30°C with optimum growth at 25°C and no growth at 5 and 35°C. Pathogenicity of the 10 isolates was tested by inoculating three of each wounded and nonwounded carrot roots with a 7-mm mycelial plug from the edge of actively growing 5-day-old cultures. Inoculated carrot roots were incubated for 7 days in a moist chamber at 23 to 25°C. Symptoms developed 3 to 7 days after inoculation, with non-wounded roots exhibiting firm, dark brown, water-soaked lesions and wounded roots exhibiting soft rot with dark brown margins. The Phytophthora sp. was always isolated from the inoculated roots. Controls remained healthy and no pathogen was isolated from these roots. On the basis of the morphological and physiological characteristics, the Phytophthora sp. isolated was identified as Phytophthora cactorum ((Lebert & Cohn) J. Schrot.) (2). Identity of these isolates was confirmed by sequencing of the internal transcriber spacers (ITS). Amplified fragment length polymorphism (AFLP) profiles for 37 isolates were >83% similar, which is expected for conspecific isolates. The ITS sequences from six representative isolates were identical and shared 100% homology to P. cactorum (GenBank Accession No. AF266772) isolated from Rubus idaeus (1). The consensus ITS sequence was deposited in NCBI (Accession No. EF052680). P. cactorum was reported in New York on field and stored carrot roots in 1952 (3), but to our knowledge, this is the first report in Michigan. Finding of P. cactorum on carrot roots represents a new and significant threat to the Michigan processing carrot industry, which ranks fourth in the United States. References: (1) D. E. L. Cooke et al. Fungal Gen. Biol. 30:17, 2000. (2) D. C. Erwin and O. K. Ribeiro. Phytophthora Disease Worldwide. The American Phytopathological Society. St. Paul, MN, 1996. (3) W. E. Rader. N Y State (Cornell) Agr. Exp. Stn. Bull. 889:5, 1952.

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First Report of Gliocephalotrichum bacillisporum Causing Fruit Rot of Rambutan (Nephelium lappaceum) in Malaysia

Plant Disease ◽

10.1094/pdis-09-12-0831-pdn ◽

2013 ◽

Vol 97 (8) ◽

pp. 1110-1110

Author(s):

M. A. Intan Sakinah ◽

Z. Latiffah

Keyword(s):

Morphological Characteristics ◽

Culture Collection ◽

Fruit Rot ◽

Tropical Fruit ◽

First Report ◽

Surface Sterilization ◽

Nephelium Lappaceum ◽

Its Regions ◽

Mycelial Plug ◽

Β Tubulin

Rambutan (Nephelium lappaceum L.) is among the tropical fruit grown in Malaysia and the demand for export rose in 2011. A fruit rot was observed between August and December 2011 from several areas in the states of Pulau Pinang and Perak, Malaysia. The symptoms initially appeared as light brown, water-soaked lesions that developed first in the pericarp and pulp, later enlarging and becoming dark brown. Greyish brown mycelia were observed on infected areas that turned yellowish at later stages of infection. Gliocephalotrichum bacillisporum was isolated from infected fruit by surface sterilization techniques. Conidia were mass-transferred onto potato dexstrose agar (PDA) plates and incubated at 27 ± 1°C. Tissue pieces (5 × 5 mm) excised from the margins between infected and healthy areas were then surface sterilized in 1% sodium hypochlorite for 3 to 5 min before being rinsed with distilled water, plated on PDA, and incubated at 27 ± 1°C for 7 days. Ten isolates of G. bacillisporum were obtained. Colonies on PDA were initially white before turning yellow with a feathery appearance. Microscopic characteristics on carnation leaf agar (CLA) consisted of hyaline conidia that were slightly ellipsoid to bacilliform with rounded apex ranging from 6.0 to 8.5 μm long and 2.0 to 2.5 μm wide. Conidiophores (70 to 130 μm long) were mostly single arising from large hypha approximately 13 to 16 μm. The conidiogenous structures were mostly quadriverticillate with dense, short, penicillate branches. The phialides were cylindrical and finger-like. Chlamydospores were present singly, in groups of 2 to 4, or in occasionally branched short chains and were brown in color with thick walls ranging from 11 to 13 μm. The cultural and morphological characteristics of G. bacillisporum isolates in the present study were very similar to previously published descriptions (1) except the conidiophores formed without sterile stipe extensions. All the G. bacillisporum isolates were deposited in culture collection at the Plant Pathology Lab, University Sains Malaysia, Penang. Molecular identification was accomplished from the ITS regions using ITS1 and ITS2 primers, and the β-tubulin gene using Bt2a and Bt2b primers (2). BLAST results from the ITS regions showed a 98 to 99% similarity with sequences of G. bacillisporum isolates reported in GenBank. Accession numbers of G. bacillisporum ITS regions: JX484850, JX484852, JX484853, JX484856, JX484858, JX484860, JX484862, JX484866, JX484867, and JX484868. The identity of G. bacillisporum isolates infecting rambutan was further confirmed by β-tubulin sequences (KC683909, KC683911, KC683912, KC683916, KC683919, KC683920, KC683923, KC683926, and KC683927), which showed 92 to 95% similarity with sequences of G. bacillisporum. Pathogenicity tests were also performed using mycelial plug (5 mm) and sprayed conidial suspensions (20 μl suspension of 106 conidia/ml) prepared from 7-day-old cultures. Inoculated fruits were incubated at 27 ± 1°C and after 10 days, similar rotting symptoms appeared on the fruit surface. The pathogen was reisolated from fruit rot lesions, thus fulfilling Koch's postulates, and tests were repeated twice. To our knowledge, this is the first report of G. bacillisporum causing fruit rot of rambutan (N. lappaceum L.) in Malaysia. References: (1) C. Decock et al. Mycologia 98:488, 2006. (2) N. L. Glass and G. C. Donaldson. Appl. Environ Microbiol. 61:1323, 1995.

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First Report of Leaf Spot of Weigela florida Caused by Epicoccum layuense in China

Plant Disease ◽

10.1094/pdis-07-20-1498-pdn ◽

2021 ◽

Author(s):

Yue Tian ◽

Yingying Zhang ◽

Chaodong Qiu ◽

Zhenyu Liu

Keyword(s):

Leaf Spot ◽

Large Subunit ◽

Morphological Characteristics ◽

Likelihood Method ◽

Pathogenicity Test ◽

Distilled Water ◽

Beta Tubulin ◽

First Report ◽

Leaf Spots ◽

Weigela Florida

Weigela florida (Bunge) A. DC. is a dense, rounded, deciduous shrub commonly planted in landscapes. It is also used in Chinese medicine to treat sore throat, erysipelas, cold, and fever (Zheng et al. 2019). In May 2019, leaf spots were observed on approximately 50% of W. florida plants grown in the Wisdom Plaza Park of Anhui Agricultural University in Hefei, Anhui Province, China. Leaf spots begun as small light brown and irregular lesions, enlarged, turned reddish brown, coalesced to form large blighted areas, and eventually covered the entire leaf surface. Five pieces of tissues were removed from the lesion margins of each diseased leaf (five leaves from five different plants), chopped into several 3-4 mm2 pieces, disinfected with 1.5% NaOCl for 2 min, rinsed 3 times with sterile distilled water for 1 min, plated onto Potato Dextrose Agar (PDA) medium containing 50 μg/ml of ampicillin and kanamycin, and incubated at 25°C with a 12-hour photoperiod for 5 days. One segment of the fungal growth from the growing edge of the colony was transferred onto a fresh PDA plate for purification and incubated under the same conditions for another 5 days. The colony morphology of one representative isolate (AAU0519) was characterized by a pale orange cushion in the center surrounded by irregular pink margin, diffusing red orange pigments into the PDA medium. Isolate AAU0519 was cultured on PDA medium for 7 days at 25°C in the dark to induce sporulation. The produced conidia were globose, subglobose to pyriform, golden brown to brown, and with a diameter of 7.7 - 23.8 μm. Both cultural and morphological characteristics suggested that isolate AAU0519 was an Epicoccum species, according to the description by Chen et al. 2017. Amplification and sequencing of the internal transcribed spacer (ITS), beta-tubulin, and 28S large subunit ribosomal RNA (LSU) gene fragments from the extracted genomic DNA of AAU0519 were performed using primer sets ITS1/ITS4 (White et al. 1990), Bt2a/Bt2b (Glass and Donaldson 1995), and LSU1Fd/LR5 (Crous et al. 2009; Vilgalys and Hester 1990), respectively. A phylogenetic tree was constructed by the maximum-likelihood method with 1,000 bootstrapping replications based on the concatenated ITS, beta-tubulin, and LSU sequences from isolate AAU0519 and representative strains of 22 species of the genus Epicoccum (Chen et al. 2017). Isolate AAU0519 clustered with ex-holotype CGMCC 3.18362 of Epicoccum layuense Qian Chen, Crous & L. Cai (Chen et al. 2017). All obtained sequences were deposited into GenBank under accession numbers MK983497 (ITS), MN328723 (beta-tubulin), and MN328724 (LSU). A pathogenicity test was conducted on leaves of five 3-year-old W. florida cultivar “Red Prince” planted in the field (five leaves for each treatment and control per plant) by spraying 30 ml of a spore suspension (106 spores/ml) of isolate AAU0519 as treatment or sterilized distilled water as control. Before the inoculation, the leaves were disinfected with 70% ethanol. After inoculation, the leaves were wrapped with a plastic bag to keep high relative humidity. The average air temperature was about 28°C during the period of pathogenicity test. The experiment was repeated once. Ten days after inoculation, the fungal-inoculated leaves developed light brown lesions resembling those of naturally infected leaves, control leaves did not develop any symptoms. E. layuense was recovered from leaf lesions and its identity was confirmed by morphological and sequence analyses as described above. To our knowledge, E. layuense has been previously reported as a pathogen of Perilla sp. (Chen et al. 2017), oat (Avena sativa) (Chen et al. 2019), and tea (Camellia sinensis) plants (Chen et al. 2020), but this is the first report of E. layuense causing leaf spot on W. florida in China. This pathogen could pose a threat to the ornamental value of W. florida plants. Thus, it is necessary to adopt effective management strategies against leaf spot on W. florida.

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First Report of Black Spot of Acanthus ilicifolius Caused by Fusarium solani in China

Plant Disease ◽

10.1094/pdis-04-14-0432-pdn ◽

2014 ◽

Vol 98 (10) ◽

pp. 1438-1438 ◽

Cited By ~ 1

Author(s):

H.-R. Su ◽

H. He ◽

Q.-Z. Huang ◽

N.-H. Lu ◽

Y.-B. Zhang

Keyword(s):

Fusarium Solani ◽

Morphological Characteristics ◽

Black Spot ◽

Morphological Observation ◽

Molecular Characteristics ◽

Beta Tubulin ◽

First Report ◽

Acanthus Ilicifolius ◽

Black Spots ◽

Initial Symptoms

Acanthus ilicifolius (family Acanthaceae) grows mainly in tropical coastal areas and is an important medicinal plant that can be used to treat asthma, rheumatism, etc. In July 2013, symptoms of black spots on the leaves of A. ilicifolius were observed in the Mangrove Conservation Area of Shenzhen Futian (22°32′ N, 114°03′ E) and Leizhou peninsula (20°12′~21°35′ N, 109°30′~110°55′ E), Guangdong Province, China. Initial symptoms of the disease were a small, dark brown spots (4 to 5 × 4 to 6 mm) surrounded by a yellow halo (1 to 2 mm in diameter), that would later extend to round or irregular black spots. Leaves eventually turned chlorotic and plants defoliated. Tissues from symptomatic leaves were excised, surface sterilized with 75% ethanol solution (v/v) for 20 s, soaked in 0.1% HgCl2 solution for 45 s, rinsed three times in sterile water, cut into small pieces (2 to 3 mm), plated on potato dextrose agar (PDA), and incubated 3 to 5 days at 28°C without light. Four isolates named from LSL-1 to LSL-4 with different morphological characteristics were obtained. To fulfill Koch's postulates, wounded and non-wounded leaves were inoculated. Fresh wounds were made with a sterile needle on detached leaves and on living plants. Mycelial plugs of each isolate were applied and covered with a piece of wet cotton to maintain moisture. For the control, the healthy leaves were inoculated with PDA plugs. All treatments were incubated at room temperature. Black spots were observed on the wounded leaves inoculated with isolate LSL-1 after 3 days, while the other three isolates and the control remained symptomless, and the pathogen similar to LSL-1 was re-isolated from the diseased leaves. Non-wounded leaves didn't become infected. The pathogenic test was repeated three times with the same conditions, and it was confirmed that LSL-1 was the pathogen causing the black spot of A. ilicifolius. Identification of the pathogen was conducted using morphological and molecular characteristics. Hyphal tips of LSL-1 were transferred to PDA medium in petri dishes for morphological observation. Two types of conidia were observed. The macroconidia were cylindrical to slightly curved, falciform shaped, with two to four septa, and measured 39 to 45 × 4.7 to 5.0 μm. The microconidia were oval to kidney shaped, single celled, 8 to 10 × 2.5 to 3.5 μm. Chlamydospores were also observed, produced singly or in pairs. Based on morphology (1,4), the isolate was tentatively identified as Fusarium solani. For molecular identification, the internal transcribed spacer (ITS) of ribosomal DNA, beta-tubulin gene, and translation elongation factor 1-alpha (EF-1α) gene was amplified using the ITS1/ITS4 (5), ITS4/ITS5 (5), T1/T2 (2) and EF1/EF2 (3) primer pairs. The gene sequences were deposited in GenBank (KJ720639 for the ITS1/ITS4 region, KF826493 for the ITS4/ITS5 region, KJ720638 for the beta-tubulin, and KF826492 for EF-1α region) and showed 99% identity to the F. solani strains (AY633746 for ITS1/ITS4 region, AM412637 for ITS4/ITS5 region, KF255996 for beta-tubulin region, DQ246859 for EF-1α region). According to these results, the pathogen of black spot of A. ilicifolius was identified as F. solani. To the best of our knowledge, this is the first report of F. solani causing black spot of A. ilicifolius in China. References: (1) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell, Ames, IA, 2006. (2) K. O'Donnell and E. Cigelnik. Mol. Phylogenet. Evol. 7:103, 1997. (3) K. O'Donnell et al. Proc. Natl. Acad. Sci. USA. 95:2044, 1998. (4) B. A. Pérez et al. Plant Dis. 91:1053, 2007. (5) A. W. Zhang et al. Plant Dis. 81:1143, 1997.

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First Report of White Mold Caused by Sclerotinia sclerotiorum on Sweet Basil in Turkey

Plant Disease ◽

10.1094/pdis-92-10-1471c ◽

2008 ◽

Vol 92 (10) ◽

pp. 1471-1471 ◽

Cited By ~ 1

Author(s):

F. M. Tok

Keyword(s):

Sclerotinia Sclerotiorum ◽

Morphological Characteristics ◽

The United States ◽

Ocimum Basilicum ◽

Pathogenicity Test ◽

Distilled Water ◽

First Report ◽

Sweet Basil ◽

Pathogenicity Tests ◽

Filter Papers

In February of 2008, wilt and collapse of sweet basil (Ocimum basilicum L.) was observed on approximately 20% of the plants in a commercial greenhouse in Demre, Antalya, Turkey. Crown and stems of infected plants were necrotic; leaves turned brown and wilted. Profuse, white mycelia and occasionally black sclerotia were found inside and outside of affected stems. Sclerotinia sclerotiorum (Lib). de Bary, identified based on morphological characteristics was isolated from sclerotia and symptomatic stems on potato dextrose agar amended with tetracycline. To conduct pathogenicity tests, sclerotia produced on carrot discs were surface disinfested in 70% ethanol and dried on sterilized filter papers. Ten sclerotia were placed in 9-cm-diameter glass petri plates containing 15 ml of sterilized distilled water. Plates were wrapped with Parafilm and incubated at 4°C for 5 to 6 weeks in the dark. Plates were then incubated at 15°C in 12 h of dark and 12 h of light. Apothecia developed after 2 weeks. Ascospores were harvested from apothecia with distilled water by crushing and shaking the apothecia in centrifuge tubes. Thirty basil plants sprayed with ascospores (106 spores per ml) were maintained in a growth chamber at 22°C and 90% humidity. After 2 weeks, necrotic leaves and stems were observed on all inoculated plants. S. sclerotiorum was recovered from symptomatic tissues. No symptoms developed on the 30 basil plants sprayed with sterile distilled water. The pathogenicity test was repeated with similar results. S. sclerotiorum on basil has been reported in Canada (4), the United States, (2,3), and Italy (1). To our knowledge, this is the first report of S. sclerotiorum on basil in Turkey. References: (1) A. Garibaldi et al. Plant Dis. 81:124, 1997. (2) G. E. Holcomb and M. J. Reed. Plant Dis. 78:924, 1994. (3) S. T. Koike. Plant Dis. 84:1342, 2000. (4) T. C. Paulitz. Plant Dis. 81:229, 1997.

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First Report of Neofusicoccum australe Associated with Botryosphaeria Canker of Grapevine in Chile

Plant Disease ◽

10.1094/pdis-07-12-0652-pdn ◽

2013 ◽

Vol 97 (1) ◽

pp. 143-143 ◽

Cited By ~ 9

Author(s):

X. Besoain ◽

C. Torres ◽

G. A. Díaz ◽

B. A. Latorre

Keyword(s):

Aerial Mycelium ◽

Pcr Primers ◽

Cabernet Sauvignon ◽

Beta Tubulin ◽

First Report ◽

Trunk Disease ◽

Tubulin Subunit ◽

Mycelial Plug ◽

Trunk Diseases ◽

Pathogenicity Tests

A survey of trunk diseases was conducted in 2010 in vineyards (n = 14) in central Chile (latitude 33°51′ to 36°30′), specifically of Vitis vinifera ‘Cabernet Sauvignon,’ which is the main wine-grape cultivar (38,806 ha) in Chile. The following symptoms of trunk disease were observed in 5- to 19-year-old grapevines: short internodes, dead spurs, dead cordons (arms), and shoot dieback. Upon cutting into cordons and trunks of symptomatic vines, brown, V-shaped cankers of hard consistency were observed. A total of 56 wood cankers were collected, and small pieces of symptomatic wood (approximately 4 mm in diameter) taken from the canker margin were surface disinfected (75% ethanol, 30 s) and placed on acidified PDA (0.5 ml of 96% lactic acid per liter; APDA), which was incubated for 4 to 7 days at 24°C. Colonies, tentatively identified as a species within the Botryosphaeriaceae based on the presence of whitish-to-gray aerial mycelium and exhibiting rapid growth (4 to 5 cm colony diameter in 48 h), were hyphal-tip purified to APDA for identification. Colonies produced globose, black pycnidia with unicellular, hyaline, ellipsoidal, densely granulate, externally smooth, and thin-walled conidia of 17.0 ± 0.7 ± 6.7 ± 0.4 μm (n = 20). A yellow pigmentation was observed at the center of 48-h colonies on APDA. Morphologically, these isolates were identified as Neofusicoccum australe (Slippers, Crous & M.J. Wingfield) Crous, Slippers & A.J.L. Phillips (2,3). BLASTn searches of the ITS rDNA region, amplified with PCR primers ITS4/ITS5 (532 bp), and a 400-bp section of the beta-tubulin subunit 2 gene amplified with primers Bt2a and Bt2b of N. australe (GenBank Accession No. JX290091 and JX679868, respectively) revealed 99% similarity with the ITS and beta-tubulin sequences of N. australe reference strains EF638778 and HQ392761, respectively. Pathogenicity tests were conducted using N. australe isolate Vid1559 on 2-year-old Cabernet Sauvignon plants (n = 4), which were inoculated by wounding the woody stem with a scalpel approximately 1 cm below the most basal bud, placing an 8-mm mycelial plug taken from a 7-day culture into the wound, and then sealing the wound with Parafilm. Non-inoculated controls (n = 4) were ‘mock’ inoculated with sterile agar plugs. After 3 months under field conditions, during spring and summer, the woody stems were examined for vascular discoloration (VD), characteristic of a wood canker. Inoculated plants had stems with light-brown, necrotic VD with a mean length of 15.2 cm, measured from the inoculation point. No VD was observed on the controls. N. australe was reisolated from 100% of the inoculated plants, completing Koch's postulates. Of 14 vineyards surveyed, 8% were infected with N. australe. N. australe is known as a trunk pathogen of grape (4), and other species of Botryosphaeriaceae have been associated with grapevine trunk disease in Chile (1). To our knowledge, this is the first report of N. australe causing Botryosphaeria canker of grape in Chile, where the pathogen is previously reported on blueberry (2). References: (1) G. A. Díaz et al. Plant Dis. 95:1032, 2011. (2) J. G. Espinoza et al. Plant Dis. 92:1407, 2008. (3) Slippers et al. Mycologia 96:1030, 2004. (4) J. R. Úrbez-Torres Phytopathol. Mediterr. 50:S5, 2011.

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First report of Athelia rolfsii causing collar rot of Phalaenopsis orchid in Taiwan

Journal of Plant Pathology ◽

10.1007/s42161-021-00785-6 ◽

2021 ◽

Author(s):

Shih-Ya Chiu ◽

Yi-Ru Lai ◽

Wen-Shi Tsai ◽

Chien-Jui Huang

Keyword(s):

Collar Rot ◽

First Report ◽

Athelia Rolfsii

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Mineralogical Characterization and Firing Temperature Delineation on Minoan Pottery, Focusing on the Application of Micro-Raman Spectroscopy

Heritage ◽

10.3390/heritage2030163 ◽

2019 ◽

Vol 2 (3) ◽

pp. 2652-2664 ◽

Cited By ~ 2

Author(s):

E. Grammatikakis ◽

Kyriakidis ◽

D. Demadis ◽

Cabeza Diaz ◽

Leon-Reina

Keyword(s):

Bronze Age ◽

Firing Temperature ◽

Raw Materials ◽

Morphological Characteristics ◽

Ceramic Technology ◽

Phase Identification ◽

Mineralogical Characterization ◽

Analytical Protocol ◽

Crucial Information ◽

Analytical Tools

Ceramic objects in whole or in fragments usually account for the majority of findings in an archaeological excavation. Thus, through examination of the values these items bear, it is possible to extract important information regarding raw materials provenance and ceramic technology. For this purpose, either traditional examination protocols could be followed, focusing on the macroscopic/morphological characteristics of the ancient object, or more sophisticated physicochemical techniques are employed. Nevertheless, there are cases where, due to the uniqueness and the significance of an object of archaeological value, sampling is impossible. Then, the available analytical tools are extremely limited, especially when molecular information and mineral phase identification is required. In this context, the results acquired from a multiphase clay ceramic dated on Early Neopalatioal period ΜΜΙΙΙΑLMIA (1750 B.C.E.–1490 B.C.E.), from the Minoan Bronze Age site at Philioremos (Crete, Greece) through the application of Raman confocal spectroscopy, a nondestructive/ noninvasive method are reported. The spectroscopic results are confirmed through the application of Xray microdiffraction and scanning electron microscopy coupled with energy dispersive Xray spectrometry. Moreover, it is demonstrated how it is made possible through the application of microRaman (μRaman) spectroscopy to examine and collect crucial information from very small inclusions in the ceramic fabric. The aim of this approach is to develop an analytical protocol based on μRaman spectroscopy, for extracting firing temperature information from other ceramic finds (figurines) where due to their uniqueness sampling and analyses through other techniques is not possible. This information can lead to dating but also to firing kiln technology extrapolations that are very significant in archaeology.

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