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Sweet potato is the 11th most important food crop in the world and an excellent source of nutrition. Postharvest diseases were monitored in sweet potato storage roots collected from the local markets in Korea during 2021. Several diseases including Fusarium surface and root rot, charcoal rot, dry rot, and soft rot were observed in the postharvest sweet potatoes. A total of 68 fungal isolates were obtained from the diseased samples, and the isolates were grouped into 8 different fungal colony types. Based on multilocus phylogeny and morphological analysis of 17 representative isolates, the isolates were identified as Fusarium oxysporum, F. ipomoeae, F. solani, Penicillium citrinum, P.&nbsp, rotoruae, Aspergillus&nbsp, wentii, Mucor&nbsp, variicolumellatus (Mu. circinelloides species complex), and Macrophomina phaseolina. F. oxysporum was the predominant pathogen as this is the most common pathogen of sweet potato storage roots causing the surface rot disease, and M. phaseolina caused the most severe disease among the pathogens. Dual culture antagonistic assays were evaluated using Trichoderma harzianum strains CMML20–26 and CMML20–27. The results revealed that the two strains showed strong antifungal activity in different ranges against all tested pathogens. This study provides an understanding of diverse postharvest diseases in sweet potatoes and suggests potential biocontrol agents to manage the diseases. In addition, this is the first report of sweet potato storage root rot diseases caused by A. wentii, and P. rotoruae worldwide.

During a survey of diseased plants on Wando Island, Korea from May to June 2020, a severe leaf spot disease was observed in the upper leaves of Japanese bay tree (Machilus thunbergii). Early symptoms were light blackish spots on the leaf surface and enlargement of older spots. Dry leaf spots surrounded with deep black margins were common throughout the plants. Symptomatic leaf samples were collected, and the causal pathogen was isolated on potato dextrose agar (PDA). Three fungal isolates (CMML20-1, CMML20-3, and CMML20-4) were cultured on PDA for morphological characterization at 25 °C in the darkness. Fungal colonies were circular, fast-growing, olivaceous to dark grey, and with abundant aerial mycelium. Sporulation was induced in 14 h-10 h light-dark conditions, and the conidia were single-celled, thin-walled with a smooth surface, ellipsoid with round apices, and measuring 17.5–20.5 (avg. 17.5) μm × 7.5–10.0 (7.9) μm. The morphological characteristics resembled those typical for Neofusicoccum parvum. Molecular identification was confirmed by partially sequencing the internal transcribed spacer (ITS) region and the translation elongation factor 1-α (EF1-α) genes. Pathogenicity tests were conducted on detached leaves and whole plants of M. thunbergii. High disease prevalence was observed, and Koch postulates were fulfilled. This is the first worldwide report of N. parvum causing leaf spots on Machilus thunbergii.

Fusarium wilt and Fusarium surface rot caused by Fusarium oxysporum Schltdl are the major diseases of sweetpotato (Ipomoea batatas) and was surveyed in different locations (Cheongju, Heanam, Iksan, Icheon, Kimje, Nonsan, Yeoungam, and Yeoju) in Korea from 2015 to 2017 in the field, after harvesting and in storehouse. The wilt incidence in the early stage represented 17.9%, 5.9%, and 8.3% in 2015, 2016, and 2017, respectively. Samples were collected, and the causal organism was isolated on potato dextrose agar (PDA). Ten pure cultures were stored at the Sweetpotato Research Laboratory, Bioenergy Crop Research Institute, Muan, Korea. Morphological analysis, along with molecular phylogeny of the sequences of internal-transcribed spacer (ITS) and elongation factor 1-&alpha, (EF-1&alpha, ) genes and their combined phylogenetic analysis, confirmed the isolates as the Fusarium oxysporum Schltdl. Pathogenicity tests were conducted on sweetpotato stems, and storage roots by artificially inoculation methods, and the most virulent isolate was selected as SPL18019. A rapid screening method on 21 selected varieties for resistant variety selection was applied on stems. The Pungwanmi was found resistant to Fusarium wilt, whereas Annobeni was the most susceptible. On the other hand, six varieties were used to test surface rot resistance, and Yulmi and Yesumi were resistant and susceptible, respectively, to Fusarium surface rot.

Black rot disease was observed in sweet potato in Korea during a disease monitoring survey in 2017. The symptoms were black, small, circular, and slightly sunken lesions in the initial stages, leading to enlarged black spots and perithecia with long necks that appeared as dark bristles in the later stages. The causative agent was isolated on potato dextrose agar (PDA) and stored at the Sweet Potato Research Laboratory, Bioenergy Crop Research Institute, RDA, Muan (SPL17100 and SPL17101). The cultured organism produced cylindrical single-celled conidia after 5 days of incubation at 25 °C with a conidial size of 8.5–65.2 × 2.6–7.3 μm. Brownish, globose, and thick-walled aleuroconidia were produced with an 11.9–17.0 × 8.3–12.2 μm size. The perithecia were globose and dark brown with long thin necks tapering from the base to the apex. Morphologically, the fungus was identified as Ceratocystis fimbriata, which was well supported by the combined phylogenetic analysis of the sequences of the internal transcribed spacer (ITS), large subunit (LSU), and elongation factor 1-α (EF-1α) genes. Pathogenicity tests were conducted, and Koch’s postulates were confirmed.

A new species belonging to the genus Alternaria was isolated from the necrotic leaf spots of Brassica rapa subsp. pekinensis in Yuseong district, Daejeon, Korea. It is an occasional isolate, not an etiological agent, which is morphologically similar to A. broccoli-italicae, but differs in conidial size and conidiophore shape. Phylogenetic analysis using the sequence datasets of the internal transcribed spacer (ITS) region of the rDNA, glyceraldehyde-3-phosphate dehydrogenase (gpd), and plasma membrane ATPase genes showed that it is distantly related to A. broccoli-italicae and closely related to Alternaria species in the section Pseudoalternaria, which belonged to a clade basal to the section Infectoriae. Morphologically, the species is unique because it produces solitary conidia or conidial chains (two units), unlike the four members in the section Pseudoalternaria that produce conidia as short branched chains. It exhibits weak pathogenicity in the host plant. This report includes the description and illustration of A. brassicifolii as a new species.

Fusarium species are important post-harvest pathogens of sweet potato worldwide. A root rot disease was observed on sweet potato (Ipomoea batatas) at storage houses in different locations in South ...

Apios americana Medik, commonly known as American groundnut, is a leguminous perennial vine crop native to North America and is cultivated in Japan and Korea (Chu et al. 2019). Its tubers are edible and believed to be very nutritious, especially for women just after childbirth. The tubers also contain secondary metabolites, saponin and genistein, which is good for human health (Ichige et al. 2013). However, the storage of tubers at inappropriate temperatures and humidity levels can cause severe fungal infection, and adversely affect tuber quality. During March and April 2020, a white to pale-orange fungal mycelia were observed on stored American groundnut tubers, with 10 to 15% of seed tubers rotten. Infected tubers were collected, and fungal isolates were isolated on potato dextrose agar (PDA) using the single spore isolation method (Leslie and Summerell 2006). A pure culture (isolate JC20003) was obtained and stored at the Bioenergy Crop Research Institute, NICS, Muan, Republic of Korea. The fungus was cultured on PDA and V8 liquid media for 7 days at 25℃ to observe its morphological characteristics. The length and width of macroconidia ranged from 20.6 to 52.9 μm and 2.9 to 5.1 μm, respectively (n = 30). The microconidia were 8.5 to 14.9 μm and 2.3 to 4.2 μm in length and width, respectively (n = 30). Macroconidia were broadly falcate, strongly septate, 2 to 6 septations with dorsiventral curvature; chlamydospores were formed in chains; and microconidia were fusiform with 0 to 1 septation observed. Genomic DNA of the isolate was extracted using Solgent DNA extraction kit (Solgent, Daejeon, Korea), followed by PCR analysis using the internal transcribed spacer (ITS5/ITS4) and elongation factor (EF-1/EF2) genes (White et al. 1990; O'Donnel 2000). PCR products were sequenced and analyzed to confirm species identity (Yang et al. 2018). These sequences were deposited in GenBank (accession numbers MT703859/ITS and MT731939/EF). BLASTn search analysis showed 100% sequence similarity with Fusarium acuminatum (isolates N-51-1/ITS and WXWH24/EF). Based on morphological and molecular data analysis, the fungus was identified as F. acuminatum (Leslie and Summerell 2006; Marin et al. 2012). Pathogenicity tests were conducted on five tubers inoculated with 5 mm mycelial plugs with three replicates, while a non-mycelial plug served as the control. After 5 days of incubation in plastic containers at 25 °C with high humidity, typical symptoms developed. No symptoms were observed on the control tubers; F. acuminatum was re-isolated from artificially inoculated tubers to complete Koch's postulates. This is the first report on post-harvest tuber rot caused by F. acuminatum in Apios americana.

Protecting food crops from viral pathogens is a significant challenge for agriculture. An integral approach to genome-editing, known as CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats and CRISPR associated protein 9), is used to produce virus-resistant cultivars. The CRISPR/Cas9 tool is an essential part of modern plant breeding due to its attractive features. Advances in plant breeding programs due to the incorporation of Cas9 have enabled the development of cultivars with heritable resistance to plant viruses. The resistance to viral DNA and RNA is generally provided using the Cas9 endonuclease and sgRNAs (single-guide RNAs) complex, targeting particular virus and host plant genomes by interrupting the viral cleavage or altering the plant host genome, thus reducing the replication ability of the virus. In this review, the CRISPR/Cas9 system and its application to staple food crops resistance against several destructive plant viruses are briefly described. We outline the key findings of recent Cas9 applications, including enhanced virus resistance, genetic mechanisms, research strategies, and challenges in economically important and globally cultivated food crop species. The research outcome of this emerging molecular technology can extend the development of agriculture and food security. We also describe the information gaps and address the unanswered concerns relating to plant viral resistance mediated by CRISPR/Cas9.

In this study, we aimed to characterize fungal samples from necrotic lesions on collar regions observed in different sweetpotato growing regions during 2015 and 2016 in Korea. Sclerotia appeared on...

Plant associated bacteria are promising alternatives to chemical fertilizers for plant growth and yield improvement in an eco-friendly manner. In this study, rice associated bacteria were isolated and assessed for mineral phosphate solubilization and indole-3-acetic acid (IAA) production activity in vitro. Six promising strains, which were tentatively identified as phylotaxon Pseudochrobactrum sp. (BRRh-1), Burkholderia sp. (BRRh-2), Burkholderia sp. (BRRh-3), Burkholderia sp. (BRRh-4), Pseudomonas aeruginosa (BRRh-5 and BRRh-6) based on their 16S rRNA gene phylogeny, exhibited significant phosphate solubilizing activity in National Botanical Research Institute phosphate growth medium, and BRRh-4 displayed the highest phosphate solubilizing activity, followed by BRRh-5. The pH of the culture broth declined, resulting in increase of growth rate of bacteria at pH 7, which might be due to organic acid secretion by the strains. In presence of L-tryptophan, five isolates synthesized IAA and the maximum IAA was produced by BRRh-2, followed by BRRh-1. Application of two most efficient phosphate solubilizing isolates BRRh-4 and BRRh-5 by root dipping (colonization) of seedling and spraying at the flowering stage significantly enhanced the growth and grain yield of rice variety BRRI dhan-29. Interestingly, application of both strains with 50% of recommended nitrogen, phosphorus and potassium fertilizers produced equivalent or higher grain yield of rice compared to the control grown with full recommended fertilizer doses, which suggests that these strains may have the potential to be used as bioinoculants for sustainable rice production.

During fungal diversity surveys of the order Eurotiales in Korea, two fungal strains, EML-DG33-1 and EML-NCP50, were isolated from samples of rat dung and fig tree leaf collected at a garden locate...

Phytophthora capsici is the most destructive peronosporomycete pathogen that causes damping-off and blight on many vegetable crops including pepper and cucurbits worldwide resulting in serious economic losses. This study was conducted to isolate and characterize novel beneficial bacteria from cropping field soils and evaluate their effects on several asexual life stages of P. capsici in vitro, and if these bacteria could suppress damping-off disease in vivo. Out of 30 bacterial isolates from this study, B-1, B-10 and B-17 significantly inhibited hyphal growth through induction of excessive branching, swelling, and cellular disintegration of P. capsici. These isolates were identified as Pseudomonas spp. through 16S rRNA gene sequencing. Live cells or culture supernatants of these antagonists also significantly suppressed formation of sporangia, release of zoospores and mycelial growth in liquid culture as revealed by dry weight of the pathogen. Interestingly, zoospores of P. capsici became immotile within a very short period of time after exposure to the 10-fold diluted culture supernatants of B-1, B-10 and B-17. However, at higher concentration of culture supernatants (5-fold diluted), part of the immotile zoospores lysed within 30–60 min. Cucumber plants grown from Pseudomonas treated seeds showed enhanced resistance to the damping-off disease caused by P. capsici compared with plants grown from non-treated seeds. Results from this study demonstrated that Pseudomonas spp. from native agro-ecological niche have great potential for controlling cucumber damping-off disease and may be used in integrated disease control to reduce reliance on synthetic chemicals.

In the course of survey of endophytic fungi from Bangladesh pumpkin seeds in 2011~2012, two strains (CNU111042 and CNU111043) with similar colony characteristics were isolated and characterized by their morphology and by molecular phylogenetic analysis of the internal transcribed spacer, glyceraldehydes-3-phosphate dehydrogenase (gpd), and Alternaria allergen a1 (Alt a1) sequences. Phylogenetic analysis of all three sequences and their combined dataset revealed that the fungus formed a subclade within the A. alternata clade, matching A. burnsi and showing differences with its other closely related Alternaria species, such as A. longipes, A. tomato, and A. tomaticola. Long ellipsoid, obclavate or ovoid beakless conidia, shorter and thinner conidial size (16~60 [90] × 6.5~14 [~16] µm) distinguish this fungus from other related species. These isolates showed more transverse septation (2~11) and less longitudinal septation (0~3) than did other related species. Moreover, the isolate did not produce any diffusible pigment on media. Therefore, our results reveal that the newly recorded fungus from a new host, Cucurbita maxima, is Alternaria burnsii Uppal, Patel & Kamat.

The fungal endophyte EML-CM25 was isolated in Korea from surface sterilized Chinese maple leaf tissues. Internal transcribed spacer sequence analysis indicated that the isolate showed 99% sequence similarity with Paraconiothyrium brasiliense, a finding that was confirmed by morphological analyses. The fungal colonies did not express aerial hyphae. Conidiomata formation was observed in the fungus cultured on potato dextrose agar at 25 o C for 7 days. Visible scattered black dots consisting of pycnidia were present throughout the colony. This is the first record of P. brasiliense in Korea.

Alternaria from different Allium plants was characterized by multilocus sequence analysis. Based on sequences of the β-tubulin (BT2b), the Alternaria allergen a1 (Alt a1), and the RNA polymerase II second largest subunit (RPB2) genes and phylogenetic data analysis, isolates were divided into two groups. The two groups were identical to representative isolates of A. porri (EGS48-147) and A. vanuatuensis (EGS45-018). The conidial characteristics and pathogenicity of A. vanuatuensis also well supported the molecular characteristics. This is the first record of A. vanuatuensis E. G. Simmons & C. F. Hill from Korea and China.

In this study, we aimed to characterize fungal samples from necrotic lesions on collar regions observed in different sweetpotato growing regions during 2015 and 2016 in Korea. Sclerotia appeared on the root zone soil surface, and white dense mycelia were observed. At the later stages of infection, mother roots quickly rotted, and large areas of the plants were destroyed. The disease occurrence was monitored at 45 and 84 farms, and 11.8% and 6.8% of the land areas were found to be infected in 2015 and 2016, respectively. Fungi were isolated from disease samples, and 36 strains were preserved. Based on the cultural and morphological characteristics of colonies, the isolates resembled the reference strain of Sclerotium rolfsii. Representative strains were identified as S. rolfsii (teleomorph: Athelia rolfsii) based on phylogenetic analysis of the internal transcribed spacer and large subunit genes along with morphological observations. To test the pathogenicity, sweetpotato storage roots were inoculated with different S. rolfsii strains. ‘Yulmi’ variety displayed the highest disease incidence, whereas ‘Pungwonmi’ resulted in the least. These findings suggested that morphological characteristics and molecular phylogenetic analysis were useful for identification of S. rolfsii.

A fungal isolate EML-NCP01 was recovered from agricultural soil in Ulleung Island, Korea. Phylogenetic analysis of internal transcribed spacer and β-tubulin genes identified the isolate as the Penicillium species P. raphiae. Morphologically, the EML-NCP01 isolate was identical to the previous description of P. raphiae. The species presented here has not been reported in Korea.

We isolated and examined a new Alternaria sp., which causes leaf spots on Peucedanum japonicum in Korea, by using molecular and morphological methods. Phylogenetic analysis based on a combined internal transcribed spacer region analysis and two protein-coding genes (gpd and Alt a1) demonstrated that the causal fungus was most closely related to A. cinerariae and A. sonchi, and relevant to A. brassicae. However, conidial morphology indicated that it is a novel species within the genus Alternaria, and therefore we have assigned the fungus a new name in this study.

During fungal diversity surveys of the order Eurotiales in Korea, two fungal strains, EML-DG33-1 and EML-NCP50, were isolated from samples of rat dung and fig tree leaf collected at a garden located in Gwangju in 2014. To complete the National Species List of Korea, it is a prerequisite to verify whether many questionable species, which were previously recorded but not confirmed, indeed present in Korea. Herein, the isolates were confirmed as undescribed species, Paecilomyces variotii and Talaromyces amestolkiae based on the combination of morphological and phylogenetic analyses of multigenes including the rDNA internal transcribed spacer, β-tubulin, and RNA polymerase II subunit 2.

Sweetpotato, Ipomoea batatas L., contains substantial levels of protein, carbohydrates, vitamins, and minerals and is popular in tropical and subtropical countries in Asia (China, Korea, and Japan), the Pacific Islands, Latin America, and Africa. Sweetpotato foot and storage tuber rot caused by the fungus Plenodomus destruens Harter are significant threats to the production of sweetpotato worldwide (Loebenstein and Thottappilly 2009). This fungus can cause disease on seedlings, mature plants, and storage roots. Decay or rot begins at the attached end, preliminarily as slight sunken lesions that become larger with time. Storage tuber rot caused by P. destruens was first observed in China in 2014 (Gai et al. 2016). Outbreaks of storage tuber rot disease were frequently observed on sweetpotato storage roots in Korea from July to August in 2015 to 2018, and it was important to confirm the cause of the disease. We collected samples from storehouses and surface sterilized with 1% NaOCl for 5 min, washed three times with sterilized distilled water, cut into small pieces, placed onto potato dextrose agar (PDA), and isolated. The selected fungi were stored at the Sweetpotato Research Laboratory, Bioenergy Crop Research Institute, Rural Development Administration, Muan, Korea (isolates SPL15025, SPL18007, and SPL18008). The representative isolate SPL15025 was cultured for 14 days on PDA and kept at 25°C with a 12-h light/dark photoperiod for sporulation. Different sized conidiomata observed and single-celled oblong to ellipsoid conidia with rounded ends were produced, measuring 6.4 to 10.6 × 1.9 to 3.9 μm (average 8.2 × 2.8 μm). The internal transcribed spacer (ITS) and translation elongation factor 1-α (EF-1α) genes were sequenced and analyzed to confirm species identity. The rDNA-ITS region was amplified with primers ITS5 and ITS4 (White et al. 1990), and EF-1α was amplified with primers EF 1 and EF 2 (O’Donnell 2000). These sequences were deposited in GenBank (accession nos. MH465671 for ITS and MH560611 for EF-1α). BLASTn search analysis showed 99 to 100% sequence similarity with P. destruens references (accession nos. JX421687/ITS and KP990656/EF-1α). Based on the conidial characteristics and DNA sequence analysis, the fungus was identified as P. destruens (Gai et al. 2016). Pathogenicity assays were conducted on two local sweetpotato varieties (Annobeni and Yonghwangmi) using a 5-mm P. destruens plug, with three replications, and a blank PDA plug served as a control. After 3 weeks of incubation in plastic containers at 25°C with high humidity, typical symptoms were detected. No symptoms were observed on the control samples, and P. destruens was reisolated from the artificially inoculated storage roots. To the best of our knowledge, this is the first report of storage tuber rot of sweetpotato caused by P. destruens in Korea.

A total of 62 bacterial isolates were obtained from Gomsohang mud flat, Mohang mud flat, and Jeju Island, Republic of Korea. Among them, the isolate CNU114001 showed significant antagonistic activity against pathogenic fungi by dual culture method. The isolate CNU114001 was identified as Bacillus amyloliquefaciens by morphological observation and molecular data analysis, including 16SrDNA and gyraseA (gyrA) gene sequences. Antifungal substances of the isolate were extracted and purified by silica gel column chromatography, thin layer chromatography, and high performance liquid chromatography. The heat and UV ray stable compound was identified as iturin, a lipopeptide (LP). The isolate CNU114001 showed broad spectrum activity against 12 phytopathogenic fungi by dual culture method. The semi purified compound significantly inhibits the mycelial growth of pathogenic fungi (Alternaria panax, Botrytis cinera, Colletotrichum orbiculare, Penicillium digitatum, Pyricularia grisea and Sclerotinia sclerotiorum) at 200 ppm concentration. Spore germ tube elongation of Botrytis cinerea was inhibited by culture filtrate of the isolate. Crude antifungal substance showed antagonistic activity against cucumber scleotiorum rot in laboratory, and showed antagonistic activity against tomato gray mold, cucumber, and pumpkin powdery mildew in greenhouse condition.

A new species of Stemphylium causing leaf and flower blight of Platycodon grandiflorus in Korea was determined on the basis of phylogenetic analysis and morphology. Phylogenetic analyses of internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (gpd), translation elongation factor 1 alpha (EF-1α) and a combined dataset revealed that the fungus placed in a subclade distinct from the closely related Stemphylium species (S. lycopersici, S. xanthosomatis and S. subglobuliferum). The fungus morphologically differs from them by producing larger conidia and no brown pigment secreted on potato dextrose agar (PDA). Hence, the pathogenic fungus is proposed as Stemphylium platycodontis sp. nov.

Two isolates of monoverticillate Penicillium species were collected from a grape and schisandra fruit in Korea. Multigene phylogenetic analyses with the nuclear ribosomal internal transcribed spacer (ITS) region and genes encoding β-tubulin (benA) and calmodulin (cmd), as well as morphological analyses revealed that the two isolates are members of the P. sclerotiorum complex in Penicillium subgenus Aspergilloides, but different from species of the P. sclerotiorum complex. The isolates are closely related to P. cainii, P. jacksonii, and P. viticola in terms of their multigene phylogeny, but their colony and conidiophore morphologies differ from those of closely related species. The name P. daejeonium is proposed for this unclassified new species belonging to the P. sclerotiorum complex in subgenus Aspergilloides.

Twenty Penicillium isolates were recovered during the investigation of fungal community in the soil samples collected from Wando (Jeonnam Province, Korea). Among them, one species was identified and described as P. cainii based on phylogentic analysis of internal transcribed spacer and β-tubulin (BT2) genes and morphological characteristics. This is a first report of P. cainii in Korea.

Powdery mildew symptoms were observed on the upper surface of leaves of Cynanchum auriculatum in Eumseong, Korea in October 2015. Microscopic observations and molecular characteristics determined this fungus as Podosphaera sp., which is reported for the first time on Cynanchum auriculatum.

Adlay seed samples were collected from 3 adlay growing regions (Yeoncheon, Jeonnam and Eumseong regions) in Korea during 2012. Among all the samples collected, 400 seeds were tested for fungal occurrence by standard blotter and test tube agar methods and different taxonomic groups of fungal genera were detected. The most predominant fungal genera encountered were Fusarium, Phoma, Alternaria, Cladosporium, Curvularia, Cochliobolus and Leptosphaerulina. The occurrence of Fusarium species were 45.6% and based on the combined sequences of two protein coding genes, EF-1a, Beta-tubulin and phylogenetic analysis, 10 species were characterized as F. incarnatum (11.67%), F. kyushense (10.33%), F. fujikuroi (8.67%), F. concentricum (6.00%), F. asiaticum (5.67%), F. graminearum (1.67%), F. miscanthi (0.67%), F. polyphialidiom (0.33%), F. armeniacum (0.33%) and F. thapsinum (0.33%). The ability of these isolates to produce mycotoxins fumonisin (FUM) and zeralenone (ZEN) were tested by ELISA quantitative analysis method. The result revealed that fumonisin (FUM) was produced only by F. fujikuroi and zeralenone (ZEN) by F. asiaticum & F. graminearum. Mycotoxigenic species were then examined for their morphological characteristics to confirm their identity. Morphological observations of the species correlated well with their molecular identification and confirmed as F. asiaticum, F. fujikuroi and F. graminearum.

Adlay seed samples were collected from 3 adlay growing regions (Yeoncheon, Jeonnam and Eumseong regions) in Korea during 2012. Among all the samples collected, 400 seeds were tested for fungal occurrence by standard blotter and test tube agar methods and different taxonomic groups of fungal genera were detected. The most predominant fungal genera encountered were Fusarium, Phoma, Alternaria, Cladosporium, Curvularia, Cochliobolus and Leptosphaerulina. The occurrence of Fusarium species were 45.6% and based on the combined sequences of two protein coding genes, EF-1a, Beta-tubulin and phylogenetic analysis, 10 species were characterized as F. incarnatum (11.67%), F. kyushense (10.33%), F. fujikuroi (8.67%), F. concentricum (6.00%), F. asiaticum (5.67%), F. graminearum (1.67%), F. miscanthi (0.67%), F. polyphialidiom (0.33%), F. armeniacum (0.33%) and F. thapsinum (0.33%). The ability of these isolates to produce mycotoxins fumonisin (FUM) and zeralenone (ZEN) were tested by ELISA quantitative analysis method. The result revealed that fumonisin (FUM) was produced only by F. fujikuroi and zeralenone (ZEN) by F. asiaticum & F. graminearum. Mycotoxigenic species were then examined for their morphological characteristics to confirm their identity. Morphological observations of the species correlated well with their molecular identification and confirmed as F. asiaticum, F. fujikuroi and F. graminearum.

Alternaria blight on araliaceous plants is a common disease caused by Alternaria panax Whetzel and occurs worldwide. Genetic diversity among 58 isolates of A. panax from different araliaceous hosts in Korea was determined by amplified fragment length polymorphism (AFLP) analysis. Selected isolates from genetic groups (determined by AFLP analysis) were examined based on the results of phylogenetic analyses of eight genes (Alt a1, BT1, BT2, EF-1α, gpd, H3, ITS, and RPB2), morphological characteristics, and pathogenicity tests. Isolates were divided into two distinct genetic groups (A and B) by AFLP analysis and based on the results of sequence analyses of the BT1, BT2, gpd, and RPB2 genes. Isolates from ginseng plants (Panax ginseng and P. quinquefolius) fell into group B, whereas isolates from the other araliaceous plants clustered in group A. Morphologically, although some overlap was observed among isolates in the two groups, isolates in group B had longer and narrower conidia, distinct sporulation patterns at 15 °C, and did not secrete pigment into PDA media. Pathogenicity tests revealed that isolates in groups A and B only induced severe disease symptoms on leaves of their hosts, such as isolates in group A on Aralia elata, Aralia continentalis, and in group B on Panax ginseng. The results indicate that the two genetic groups of Alternaria from araliaceous plants should be considered as two different species, and we propose that group A is a candidate of new Alternaria species distinguished from A. panax.

A species of Heterobasidion was encountered during a diversity study of endophytic fungi from healthy root tissues of chili pepper (Capsicum annuum L.) in Korea. The fungal species (CNU081069) was identified as Heterobasidion araucariae based on phylogenetic analyses of the internal transcribed spacer and translation elongation factor gene sequences. Morphological descriptions of the endophytic isolate matched well with the previous references and supported the molecular identification. The fungus Heterobasidion araucariae CNU081069 is new to Korea.

This study investigated the distribution of endophytic fungi obtained from the surface sterilized tissues of leaves, stems and roots of chili pepper (Capsicum annuum L.) plants in seedling, flowering and fruiting stages in Korea and their antifungal activity. A total of 481 isolates were recovered and were identified using molecular techniques. Based on rDNA ITS gene sequence and phylogenetic analysis, 21 fungal genera were characterized, belonging to 16 Ascomycota and 5 Basidiomycota. Penicillium in seedling stage, Fusarium in flowering stage, Colletotrichum followed by Fusarium, Alternaria and Xylaria in fruiting stage was predominant and Alternaria, Cladosporium and Fusarium were common in all growth stages. Among 481 endophytes 90 phenotypes were evaluated for the antimicrobial activity against three major pathogens (Phytophthora capsici, Colletotrichum acutatum and Fusarium oxysporum) of chili pepper. Among them 16 isolates inhibited the growth of at least one test microorganisms. Three strains showed a broad spectrum antifungal activity and displayed strong inhibition against chili pepper pathogenic fungi.

Species of Phoma and its allies were isolated during a survey on the diversity of endophytic fungi associated with pine trees in Korea. Based on the phylogenetic analyses of internal transcribed spacer and β-tubulin gene sequences, two Phoma-like species from the needles of Pinus koraiensis were identified as Peyronellaea calorpreferens and P. glomerata. They were also morphologically identified based on the previous descriptions. Here, we report P. calorpreferens and P. glomerata being present in Korea as endophytic fungi in Pinus koraiensis.