scholarly journals First Report of Crown and Stem Rot of Orchid (Orchis palustris) Caused by Sclerotinia minor

Plant Disease ◽  
2005 ◽  
Vol 89 (8) ◽  
pp. 913-913
Author(s):  
C. Eken ◽  
S. Ercişli ◽  
A. Eşitken ◽  
E. Demirci ◽  
G. Y. Yuen
Keyword(s):  
Potato Dextrose Agar ◽  
Stem Rot ◽  
Eastern Anatolia ◽  
Forage Production ◽  
Sclerotinia Minor ◽  
Transparent Plastic ◽  
First Report ◽  
Plastic Bags ◽  
White Mycelium ◽  
Plant Pathol

Orchis palustris Jacq. is a wild orchid native to wetlands in eastern Anatolia. During June of 2003, near Erzurum, Turkey, a decline of this orchid was observed in several meadows that had been irrigated for forage production. Stems were chlorotic, wilted, and collapsed. There was a soft, watery rot at the crowns and lower stems. White mycelium and black sclerotia formed on necrotic stem and crown tissues. The fungus was isolated from sclerotia on potato dextrose agar (PDA) and identified as Sclerotinia minor Jagger on the basis of small sclerotia (0.5 to 2.5 mm long) scattered throughout the colonies (2). Pathogenicity was confirmed by inoculating stems of 8-week-old plants with mycelial plugs from 5-day-old PDA cultures and enclosing inoculated plants in transparent plastic bags for 3 days. After 2 weeks, symptoms similar to those in the field were observed, and S. minor was reisolated from inoculated plants. Noninoculated control plants remained asymptomatic. The disease was previously observed on O. laxiflora Lam. in Turkey (1), but to our knowledge, this is the first report of S. minor infecting O. palustris References: (1) C. Eken et al. Plant Pathol. 52:802, 2003. (2) L.M. Kohn. Phytopathology 69:881, 1979.

scholarly journals First Report of Stem Rot and Wilt of Sunflower Caused by Sclerotinia minor in Spain

Plant Disease ◽  
2002 ◽  
Vol 86 (6) ◽  
pp. 697-697
Author(s):  
M. L. Molinero-Ruiz ◽  
J. M. Melero-Vara
Keyword(s):  
Helianthus Annuus ◽  
Root Rot ◽  
Mycelial Growth ◽  
Disease Incidence ◽  
Potato Dextrose Agar ◽  
Stem Rot ◽  
Sclerotinia Minor ◽  
Stem Base ◽  
First Report ◽  
White Mycelium

In 2001, sunflower (Helianthus annuus L.) plants with symptoms of stem and root rot and wilt were observed in Soria, Spain. Light brown, water-soaked lesions developed on the collar of infected plants and extended along the stem, affecting the pith and causing early and sudden wilt. White mycelium and sclerotia (0.5 to 2 mm long) formed in the pith of stems. The sclerotia were disinfested in NaClO (10% vol/vol) for 1 min, transferred to potato dextrose agar (PDA), and incubated at 20°C. The fungus consistently obtained was identified as Sclerotinia minor Jagger (1). Pathogenicity was confirmed in a greenhouse experiment (15 to 25°C, 13 h light). Seven-week-old plants of six genotypes of sunflower (‘Peredovik’, HA89, HA821, HA61, RHA274, and HA337) were inoculated by placing one PDA disk with active mycelial growth adjacent to each basal stem just below the soil line and covering it with peat/sand/silt (2:2:1, vol/vol). Six plants of each genotype were inoculated without wounding, and another six were inoculated immediately after stem base wounding with a scalpel; six wounded and uninoculated plants were used as controls. First symptoms (wilting) appeared 4 days after inoculation in all genotypes. Two weeks after inoculation, the percentage of dead plants ranged from 33 to 92% (depending on cultivar), white mycelium was observed at the base of affected plants, and sclerotia were present in the pith of diseased plants. There was no effect of plant wounding on disease incidence or severity, and the fungus was reisolated from inoculated plants. To our knowledge, this is the first report of S. minor in Spain. Reference: (1) L. M. Kohn. Mycotaxon IX 2:365, 1979.

scholarly journals First Report of Sclerotinia sclerotiorum on Coneflower

Plant Disease ◽  
1997 ◽  
Vol 81 (9) ◽  
pp. 1093-1093 ◽  
Author(s):  
K. F. Chang ◽  
R. J. Howard ◽  
R. G. Gaudiel ◽  
S. F. Hwang
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Echinacea Purpurea ◽  
Stem Rot ◽  
Perennial Herb ◽  
Sclerotinia Stem Rot ◽  
Transparent Plastic ◽  
Potato Dextrose Agar Medium ◽  
First Report ◽  
Plastic Bags ◽  
Stem Lesions

Purple coneflower (Echinacea purpurea (L.) Moench; Asteraceae), a perennial herb originating from North America, is used as a garden ornamental and is grown commercially for use in medicinal preparations as an immunostimulant. In October 1996, a previously undescribed stem rot disease was observed in a research plot of 6-month-old echinacea plants at Brooks. Seedlings had been raised in small rockwool cubes (2 × 2 × 5 cm3) in a greenhouse, then transplanted into the field in early June. By late August, dead and dying plants were observed throughout the stand. They had dark brown to black stem lesions above and at the soil level and dead leaves with bleached petiole lesions that extended ca. 15 cm above the axil. Diseased stems and petioles often disintegrated, leaving only fibrous tissues intact. Roots were rotted and black. Superficial white mycelium developed over the basal part of affected stems. Black, oblong to irregular-shaped sclerotia, 5.1 to 17.6 mm in size, formed externally on the crown areas after plant death. Sclerotinia sclerotiorum (Lib.) de Bary (1) was isolated from the diseased plants. Five isolates were selected to fulfill Koch's postulates with 3-month-old echinacea seedlings grown in 12-cm pots of soilless mix. Sclerotia from wilted, field-grown echinacea plants were transferred onto potato dextrose agar medium for 2 days at 20°C. Agar disks were cut with a 1-cm cork borer and two plugs containing sclerotial and mycelial tissues were inserted into the soilless mix 0.5 cm deep and 0.5 cm from the opposite sides of stems of test plants. Inoculated plants were enclosed in transparent plastic bags for 5 days and incubated in a growth chamber at 15/18°C (night/day) with a 12-h photoperiod. One to four lower leaves per plant wilted within 1 week after inoculation and aerial mycelia appeared on the petioles. Infected leaves quickly withered, dried, and dropped off the plant after the bags were removed. Plants often died 3 weeks after inoculation and S. sclerotiorum was reisolated from infected crown tissues. This disease was also found on 3-year-old plants of E. pallida (Nutt.) Nutt. var. angustifolia (DC.) Cronq. in Vernon, British Columbia, Canada, in May 1997. This is the first report of sclerotinia stem rot on Echinacea spp., a disease that could have a significant impact on the longevity and productivity of this crop in the field and greenhouse. Reference: (1) L. H. Purdy. Phytopathology 69:875, 1979.

scholarly journals First Report of Stem Blight Caused by Botrytis cinerea on Jasminum officinalis in Italy

Plant Disease ◽  
2008 ◽  
Vol 92 (12) ◽  
pp. 1708-1708
Author(s):  
D. Aiello ◽  
G. Parlavecchio ◽  
A. Vitale ◽  
G. Polizzi
Keyword(s):  
Botrytis Cinerea ◽  
Far East ◽  
Weather Conditions ◽  
Economic Loss ◽  
Transparent Plastic ◽  
Disease Symptoms ◽  
First Report ◽  
Stem Blight ◽  
Plastic Bags ◽  
Stem Lesions

Common jasmine (Jasminum officinalis L.) is an evergreen shrub that is native to the Middle and Far East. It is widely grown in Europe as an ornamental plant and in southeastern France for fragrance for the perfume industry. In March of 2008, a previously undescribed disease was observed on potted (6-month- to 3-year-old) common jasmine plants growing in open fields in a nursery of eastern Sicily, Italy. More than 20% of the plants showed disease symptoms. Diseased plants had small to large, brown or black lesions on stem. The lesions expanded rapidly, girdled the stem and caused blight of entire branches, and occasionally killed the plant. Abundant conidia and mycelia were detected on the surface of dead and dying stems under cool and humid conditions, which resulted in a moldy gray appearance. Botrytis cinerea Pers.:Fr. (1) was consistently isolated from affected tissues disinfected for 1 min in 1% NaOCl, rinsed in sterile water, and plated on potato dextrose agar (PDA). Colonies were at first white then became gray after 6 to 7 days when spores differentiated. White sclerotia developed after 8 to 9 days and turned black with age. Size of the conidia produced on 1-month-old culture ranged from 5.0 to 9.5 × 6.5 to 12.5 μm on the basis of 50 spore measurements. Sclerotia were spherical or irregular and ranged from 1.0 to 2.5 × 0.9 to 2.9 mm (average 1.7 × 1.8 mm). Stems of eight 6-month-old common jasmine plants were lightly wounded with a sterile razor and inoculated with 3-mm-diameter plugs of PDA from 10-day-old mycelial cultures, eight similar plants were inoculated with mycelium without wounding, and an equal number of noninoculated plants inoculated with only PDA plugs served as control. After inoculation, plants were enclosed in transparent plastic bags at 20 ± 2°C for 5 days. Stem lesions identical to the ones observed in the nursery were detected on all wounded and on two nonwounded fungus-inoculated plants within 5 to 7 days. Control plants remained healthy. B. cinerea was reisolated from typical lesions. The unusually cool and humid weather conditions recorded in Sicily are supposed to be highly conducive of disease outbreak. Although B. cinerea does not usually kill the plants, under these environmental conditions this disease can cause significant economic loss to ornamental nurseries. To our knowledge, this is the first report of B. cinerea causing stem blight on J. officinalis. Reference: (1) M. B. Ellis. Dematiaceous Hyphomycetes. CAB, Kew, Surrey, England, 1971.

scholarly journals First Report of Stem and Crown Rot of Garbanzo Caused by Sclerotinia minor in the United States and by Sclerotinia sclerotiorum in Arizona

Plant Disease ◽  
2000 ◽  
Vol 84 (11) ◽  
pp. 1250-1250 ◽  
Author(s):  
M. E. Matheron ◽  
M. Porchas
Keyword(s):  
United States ◽  
Cicer Arietinum ◽  
Soil Surface ◽  
The United States ◽  
Crown Rot ◽  
Sclerotinia Minor ◽  
First Report ◽  
Initial Symptoms ◽  
Stem Necrosis ◽  
White Mycelium

In March 2000, plants began to die within two garbanzo (Cicer arietinum L.) fields about 48 km apart in southwestern Arizona. Initial symptoms included wilting of leaves and stem necrosis on individual branches, followed by entire plant necrosis and death. White mycelium was present on plant stems near the soil surface. In one field, small black irregularly shaped sclerotia (1 mm in diameter) were present on the infected stem surface along with the white mycelia, whereas in the other field the associated sclerotia were of similar shape but larger (5 to 6 mm in diameter). Isolation from diseased garbanzo stem tissue from the respective fields yielded Sclerotinia minor, which produced small sclerotia when cultured on potato-dextrose agar and S. sclerotiorum, which produced the typical larger sclerotia of this species. To fulfill Koch's postulates, healthy plants and associated soil from a garbanzo field with no evidence of infection by Sclerotinia were removed with a shovel and transferred into a series of 8-liter plastic pots. After transporting back to the laboratory, some of the plants were inoculated by wounding stems with a 5-mm-diameter cork borer, placing an agar disk containing either S. minor or S. sclerotiorum onto each wound, securing the agar disk to the stem with plastic tape, then incubating the plants at 25°C for 7 days. Control plants were treated similarly except that agar disks did not contain Sclerotinia. Stems inoculated with S. minor or S. sclerotiorum developed symptoms of wilt and necrosis, including the appearance of white mycelium and sclerotia on the stem surface, whereas control plants remained healthy. S. minor or S. sclerotiorum were recovered from garbanzo stems inoculated with the respective species of the pathogen. Sclerotinia leaf drop, which can be caused by S. minor or S. sclerotiorum on lettuce in Arizona, had been observed in both fields previously. Garbanzo fields in Arizona usually are watered by furrow irrigation. Disease was most severe in areas of the garbanzo fields that were heavily irrigated with resultant wetting of tops of plant beds. Proper management of irrigation water and avoidance of establishing a garbanzo planting in fields following lettuce could help reduce future losses from these pathogens. S. minor previously had been reported as a pathogen on Cicer arietinum from the island of Sardinia (2); however, this is apparently the first report of the pathogen on garbanzo other than in Sardinia. S. sclerotiorum has been reported as a pathogen on this host in several countries including the United States (California) (1) but not previously in the state of Arizona. References: (1) I. W. Buddenhagen, F. Workneh, and N. A. Bosque-Perez. Int. Chickpea Newsl. 19:9–10, 1988. (2) F. Marras. Rev. Appl. Mycol. 43:112, 1964.

scholarly journals Stem and Crown Rot of Chervil, Caused by Sclerotinia sclerotiorum, in California

Plant Disease ◽  
1999 ◽  
Vol 83 (12) ◽  
pp. 1177-1177 ◽  
Author(s):  
S. T. Koike
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Early Spring ◽  
Potato Dextrose Agar ◽  
Crown Rot ◽  
Apium Graveolens ◽  
Pathogenicity Tests ◽  
Related Plant ◽  
White Mycelium ◽  
Plant Pathol ◽  
Mist Chamber

Chervil (Anthriscus cerefolium) is a culinary herb grown commercially in California. In 1999, chervil plantings in shade houses in coastal California exhibited symptoms of a previously undescribed disease. Tan to gray lesions, surrounded by pinkish tissue, developed on crowns and lower sections of stems. Affected stems wilted, and plants eventually collapsed and rotted. More than 50% of the plants in the early spring planting were diseased. White mycelium and large, irregular, black sclerotia (3 to 6 mm diameter) were observed on infected stems and crowns. Isolations from symptomatic stems, mycelium, and sclerotia produced colonies of Sclerotinia sclerotiorum. Following previously described methods (2), pathogenicity was confirmed by culturing isolates on potato dextrose agar and allowing the fungus to colonize sterilized toothpicks placed on the surface of the agar. The pointed toothpick tips were inserted ≈3 mm deep in stems of potted chervil. Sterile toothpicks were inserted in control chervil plants. All plants were incubated in a mist chamber for 48 h and then kept in a greenhouse. Two other hosts of S. sclerotiorum, cauliflower (Brassica oleracea var. botrytis cv. White Rock) and celery (Apium graveolens cv. Conquistador)were inoculated in the same way. After 7 to 10 days, symptoms and mycelium similar to those originally observed developed on inoculated chervil plants, and S. sclerotiorum was reisolated. Plants left for 14 or more days supported sclerotia. Chervil inoculated with sterile, uncolonized toothpicks did not develop symptoms. Results were similar for cauliflower and celery plants. Pathogenicity tests were repeated, and the results were similar. A separate set of chervil was inoculated by placing sclerotia at the base of plants; these plants also developed disease but at a much lower incidence (<50%). This is the first report of Anthriscus cerefolium as a host of S. sclerotiorum. The related plant cow parsley (A. sylvestris) has been reported as a host of S. sclerotiorum in England (1). References: (1) M. J. Hims. Plant Pathol. 28:197, 1979. (2) S. T. Koike. Plant Dis. 81:1334, 1997.

scholarly journals First Report of a Bionectria sp. Associated with a Stem Rot of Cardon Cactus (Pachycereus pringlei) in Baja California Sur, Mexico

Plant Disease ◽  
2012 ◽  
Vol 96 (2) ◽  
pp. 292-292 ◽  
Author(s):  
R. J. Holguín-Peña ◽  
L. G. Hernández-Montiel ◽  
H. Latisnere ◽  
E. O. Rueda-Puente
Keyword(s):  
Gulf Of California ◽  
Baja California ◽  
Morphological Characteristics ◽  
Potato Dextrose Agar ◽  
Control Measures ◽  
World Heritage Site ◽  
Stem Rot ◽  
Baja California Sur ◽  
First Report ◽  
Pachycereus Pringlei

Giant cardon (Pachycereus pringlei ((S.Watson) Britton & Rose) is the most common cactus in northwestern Mexico and is endemic to the Baja California Peninsula and Sonora Desert. A large part of the peninsula (El Vizcaino Biosphere Reserve and Gulf of California) now consists of protected areas and is classified as a World Heritage site by UNESCO ( http://whc.unesco.org/en/list/1182 ). Cardon cactus is an important ecological resource for indigenous people and is used as feed for range cattle. Since 2000, in the central and southern part of the State of Baja California Sur, an apical stem rot has spread to ~17% of the natural cardon population around San Pedro (23°29′N, 110°12′W), La Paz (24°08′N, 110°18′W), and El Comitán (24°05′N, 110°21′W). Affected cacti display necrosis of apical branches, dry rot, cracks in the stem and branches, bronzing of mature spines surrounding the affected area, and reddish brown gummy exudate. Thirty samples from the edges of symptomatic lesions were surface disinfected for 2 min in 0.8% (wt/vol) NaOCl and ethanol (70%), rinsed in sterile, distilled water, and grown on potato dextrose agar at 27°C. A cottony, brownish fungus was consistently isolated from affected tissues. Koch's postulates were performed in pots of 10 cm in diameter with 5-year-old cacti inoculated (9-day-old mycelia) and incubated (15 days) at room temperature (26°C). The rough, dry, brownish, circular lesions that appeared were the same as those observed in the field. Healthy cacti inoculated with potato dextrose agar plugs were symptomless. The fungus was always reisolated from infected cacti and morphological examinations (2) were performed: one-septate, olive-green, smooth, ellipsoidal conidium and two-celled ascospores (15 to 20 × 5 to 7 μm) were present. Also present were conidial masses from monomorphic, penicillate conidiophores in sporodochia. Cottony and white-to-light yellow PDA colonies were observed. Genomic DNA was extracted from lyophilized hyphae using the method described by O'Donnell (1) or with a DNeasy Plant Mini Kit (Qiagen, Hilden, Germany). The internal transcribed spacer (ITS) regions 1 and 2 of the 5.8, 18, and 28S ribosomal RNA genes were amplified with the primer pairs ITS1 and ITS4 (3). The expected amplicon of 571 bp was sequenced and compared with fungal sequences available from the GenBank-EMBL database using the BlastN and CLUSTAL programs (MegAlign, DNASTAR, Madison, WI). The closest nucleotide similarity had 99% identity with a Bionectria sp. (GenBank Accession No. HM849058.1). To our knowledge, on the basis of morphological characteristics, DNA comparisons, and pathogenicity tests, this is the first report of a Bionectria sp. causing an apical stem rot disease in cardon cacti in Mexico. Since there are no control measures in Mexico there is a permanent risk that the disease will spread to healthy areas. References: (1) K. O'Donell et al. Mycologia 92:919, 2000. (2) H. J. Schroers. Stud. Mycol. 46:1, 2001. (3) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.

scholarly journals First Report of Stem Rot in Canola Caused by Sclerotinia minor in Western Australia

Plant Disease ◽  
2013 ◽  
Vol 97 (12) ◽  
pp. 1660-1660 ◽  
Author(s):  
R. Khangura ◽  
W. J. MacLeod
Keyword(s):  
Western Australia ◽  
Management Strategies ◽  
Fungal Growth ◽  
Stem Rot ◽  
Correct Identification ◽  
Pathogenicity Test ◽  
Sclerotinia Minor ◽  
Brassica Napus L ◽  
First Report ◽  
South Wales

Canola (Brassica napus L.) is a significant oilseed break crop in Western Australia. In late October 2012, canola plants (cv. Jackpot) showing typical symptoms of stem rot with bleached appearance and fluffy white fungal growth on the infected tissues were observed in an experimental plot at Katanning, Western Australia. Severely affected plants were lodged with partially filled pods and shriveled seeds. Small, irregular sclerotia (<2 mm) were found inside the plants and were more concentrated in the root and basal stem than in the upper stem regions. Ten sclerotia from three symptomatic plants were surface sterilized with 1.25% NaOCl for 1 minute, rinsed twice in sterile distilled water and plated on potato dextrose agar (PDA) supplemented with 10 mg liter–1 Aureomycin. Plates were incubated under a black light at 22 ± 2°C. Sclerotinia minor Jagger was consistently isolated as identified by colony morphology, abundant sclerotia on PDA, and size of sclerotia <2 mm (3). A pathogenicity test was conducted on six 7-week-old canola plants cv. Tawriffic. Mycelial plugs (5 mm diameter) were excised from the margins of actively growing 3-day-old cultures and attached on to the 2nd and the 4th internodes of the main stem with Parafilm. Three plants inoculated with agar plugs without mycelium served as controls. Following inoculation, the plants were kept in a misting chamber for 48 h and then transferred to a growth room at 18 ± 2°C with a 12-h photoperiod. Typical lesions of stem rot similar to those observed in the field were noticed 3 days after inoculation. Within a week, all the inoculated plants were completely girdled by the lesions with stems breaking off and collapsing at the point of inoculation. Small sclerotia formed within lesions on the outside of the diseased stems. S. minor was reisolated from the stems of symptomatic plants, fulfilling Koch's postulates. No symptoms developed on the control plants. S. minor has previously been reported on host plants other than canola in Western Australia (4), canola petals in New South Wales, Australia (2), and also on canola stems in Argentina (1). To our knowledge, this is the first report of occurrence of S. minor on canola in Western Australia. Although S. sclerotiorum is the predominant species causing stem rot in canola in Western Australia, S. minor has the potential to cause significant yield losses under favorable environmental conditions. Correct identification and monitoring a shift in pathogens is essential for implementing effective management strategies and breeding resistant varieties. References: (1) S. A. Gaetán et al. Plant Dis. 92:172, 2008. (2) T. Hind-Lanoiselet et al. Aust Plant Pathol. 30:289, 2001. (3) L. M. Kohn. Phytopathology 69:881, 1979. (4) R. Shivas. J. Royal. Soc. Western Australia 72:1, 1989.

scholarly journals First Report of Stem Rot of Sunflower Broomrape (Orobanche cumana) Caused by Sclerotinia minor Jagger in Inner Mongolia, China

Plant Disease ◽  
2018 ◽  
Vol 102 (3) ◽  
pp. 683-683 ◽  
Author(s):  
J. Zhang ◽  
R. Jia ◽  
Y. Zhang ◽  
M. Li ◽  
H. Zhou ◽  
...  
Keyword(s):  
Inner Mongolia ◽  
Stem Rot ◽  
Sclerotinia Minor ◽  
First Report ◽  
Orobanche Cumana ◽  
Sunflower Broomrape

scholarly journals First Report of Leaf Spot Caused by Phoma dictamnicola on Dictamnus dasycarpus in Korea

Plant Disease ◽  
2014 ◽  
Vol 98 (10) ◽  
pp. 1443-1443
Author(s):  
J. H. Park ◽  
S. E. Cho ◽  
C. K. Lee ◽  
S. H. Lee ◽  
H. D. Shin
Keyword(s):  
Leaf Spot ◽  
Its Region ◽  
Molecular Data ◽  
Culture Collection ◽  
Morphological Identification ◽  
Conidial Suspension ◽  
Aesthetic Value ◽  
Transparent Plastic ◽  
First Report ◽  
Plastic Bags

Dictamnus dasycarpus Turcz, known as densefruit pittany, is a perennial herbal plant belonging to the Rutaceae. In Oriental medicine, this plant is used for treatment of various ailments (4). Since the white and purple striped flowers and glossy leaves are of aesthetic value, the plant is popular in gardens throughout Korea. In July 2012, a leaf spot was observed on hundreds of D. dasycarpus with nearly 100% incidence in a garden in Gapyeong County, Korea. Lesions on leaves reaching up to 20 mm in diameter were circular to irregular, brown to dark brown, then becoming zonate with age, and finally fading to grayish brown in the center with a reddish brown margin. The disease caused premature defoliation and reduced plant vigor as well as aesthetic value. In June 2014, the same symptoms were found on D. dasycarpus in a nursery in Jinju City, Korea. Representative samples were deposited in the Korea University Herbarium (KUS). Pycnidia on lesions were epiphyllous, immersed or semi-immersed in host tissue, light brown to olive brown, and 90 to 210 μm in diameter. Ostioles were 15 to 30 μm wide and surrounded by a ring of darker cells. Conidia were hyaline, smooth, ellipsoidal to nearly reniform, straight to mildly curved, aseptate or rarely medianly 1-septate with age, 5.5 to 9.6 × 1.8 to 3.6 μm, and contained small oil drops. These characteristics were consistent with the previous descriptions of Phoma dictamnicola Boerema, Gruyter & Noordel. (1,2). A monoconidial isolate was cultured on potato dextrose agar plates and deposited in the Korea Agricultural Culture Collection (Accession No. KACC46948). Morphological identification of the fungus was confirmed by molecular data. Genomic DNA was extracted using a DNeasy Plant Mini Kit (Qiagen Inc., Valencia, CA). The internal transcribed spacer (ITS) region of rDNA was amplified using the ITS1/ITS4 primers and sequenced. The resulting sequence of 505 bp was deposited in GenBank (Accession No. KM047023). A BLAST search showed that the ITS sequence shared >99% similarity with that of P. dictamnicola (GU237877). For the pathogenicity tests, inoculum was prepared by harvesting conidia from 30-day-old cultures of KACC46948 and a conidial suspension (2 × 106 conidia/ml) was sprayed onto leaves of five healthy seedlings. Five seedlings were sprayed with sterile distilled water, serving as controls. The plants were covered with transparent plastic bags for 48 h in a 25°C glasshouse with a 12-h photoperiod. After 10 days, typical leaf spot symptoms started to develop on the leaves of the inoculated plants. The fungus, P. dictamnicola, was re-isolated from those lesions, confirming Koch's postulates. No symptoms were observed on control plants. Previously, Phoma leaf spot on Dictamnus spp. has been reported in the Netherlands and North America (3) and recently in China (1). To our knowledge, this is the first report of leaf spot on D. dasycarpus caused by P. dictamnicola in Korea. Our observations suggest that low humidity with good ventilation as well as removal of infected leaves and plant debris might be main strategies for preventing this disease. References: (1) Q. Bai et al. Plant Dis. 95:771, 2011. (2) G. H. Boerema et al. Phoma Identification Manual: Differentiation of Specific and Infra-Specific Taxa in Culture. CABI Publishing. Wallingford, UK, 2004. (3) D. F. Farr and A. Y. Rossman. Fungal Databases. Syst. Mycol. Microbiol. Lab., Online publication, USDA ARS, Retrieved June 19, 2014. (4) J. L. Yang et al. Planta Med. 77:271, 2011.

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