1.Tobacco Growth Promotion by the Entomopathogenic Fungus, Isaria javanica pf185
Yong Seong LEE ; Young Cheol KIM
Mycobiology 2019;47(1):126-133
Isaria javanica pf185 is an important entomopathogenic fungus with potential for use as an agricultural biocontrol agent. However, the effect of I. javanica pf185 on plant growth is unknown. Enhanced tobacco growth was observed when tobacco roots were exposed to spores, cultures, and fungal cell-free culture supernatants of this fungus. Tobacco seedlings were also exposed to the volatiles of I. javanica pf185 in vitro using I-plates in which the plant and fungus were growing in separate compartments connected only by air space. The length and weight of seedlings, content of leaf chlorophyll, and number of root branches were significantly increased by the fungal volatiles. Heptane, 3-hexanone, 2,4-dimethylhexane, and 2-nonanone were detected, by solid-phase micro-extraction and gas chromatography-mass spectrophotometry, as the key volatile compounds produced by I. javanica pf185. These findings illustrate that I. javanica pf185 can be used to promote plant growth, and also as a biocontrol agent of insect and plant diseases. Further studies are necessary to elucidate the mechanisms by which I. javanica pf185 promotes plant growth.
Chlorophyll
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Fungi
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In Vitro Techniques
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Insects
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Plant Diseases
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Plants
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Seedlings
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Spectrophotometry
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Spores
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Tobacco
2.A New Record and Characterization of Asparagus Purple Spot Caused by Stemphylium vesicarium in Korea
Joon Hee HAN ; Jong Hwan SHIN ; Teng FU ; Kyoung Su KIM
Mycobiology 2019;47(1):120-125
In 2017, small, elliptical, brownish purple spots on spears and ferns of asparagus were found in fields of Gangwon-do. The isolated fungal species was identified as an ascomycete Stemphylium vesicarium based on morphological characteristics and molecular phylogenic analyses including nucleotide sequences of the internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and cytochrome b (cytb). A pathogenicity test revealed that S. vesicarium was the causal agent of purple spot disease on asparagus. The occurrence of purple spots caused by S. vesicarium on asparagus is the first report in Korea.
Ascomycota
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Base Sequence
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Cytochromes b
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Ferns
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Gangwon-do
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Korea
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Oxidoreductases
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Virulence
3.Anti-Melanogenic Effect from Submerged Mycelial Cultures of Ganoderma weberianum
Ying Jang LAI ; Kai Di HSU ; Tzu Jung HUANG ; Chang Wei HSIEH ; Yu Hin CHAN ; Kuan Chen CHENG
Mycobiology 2019;47(1):112-119
Compounds from Lingzhi has been demonstrated the ability for inhibiting tyrosinase (a key enzyme in melanogenesis) activity. In this study, we investigated the anti-melanogenic activity from the submerged mycelial culture of Ganoderma weberianum and elucidated the skin lightening mechanism by B16-F10 murine melanoma cells. From the cellular context, several fractionated mycelium samples exhibited anti-melanogenic activity by reducing more than 40% extracellular melanin content of B16-F10 melanoma cells. In particular, the fractionated chloroform extract (CF-F3) inhibited both secreted and intracellular melanin with the lowest dosage (25 ppm). Further analysis demonstrated that CF-F3 inhibited cellular tyrosinase activity without altering its protein expression. Taken together, our study has demonstrated that the chemical extracts from submerged mycelial culture of G. weberianum have the potential to serve as an alternative anti-melanogenic agent.
Chloroform
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Ganoderma
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Melanins
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Melanoma
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Monophenol Monooxygenase
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Mycelium
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Reishi
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Skin
4.Efficacy of Diphenyleneiodonium Chloride (DPIC) Against Diverse Plant Pathogens
Boknam JUNG ; Taiying LI ; Sungyeon JI ; Jungkwan LEE
Mycobiology 2019;47(1):105-111
Many of the fungicides and antibiotics currently available against plant pathogens are of limited use due to the emergence of resistant strains. In this study, we examined the effects of diphenyleneiodonium chloride (DPIC), an inhibitor of the superoxide producing enzyme NADPH oxidase, against fungal and bacterial plant pathogens. We found that DPIC inhibits fungal spore germination and bacterial cell proliferation. In addition, we demonstrated the potent antibacterial activity of DPIC using rice heads infected with the bacterial pathogen Burkholderia glumae which causes bacterial panicle blight (BPB). We found that treatment with DPIC reduced BPB when applied during the initial flowering stage of the rice heads. These results suggest that DPIC could serve as a new and useful antimicrobial agent in agriculture.
Agriculture
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Anti-Bacterial Agents
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Burkholderia
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Cell Proliferation
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Flowers
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Germination
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Head
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NADPH Oxidase
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Plants
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Spores, Fungal
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Superoxides
5.Development of a Novel Spawn (Block Spawn) of an Edible Mushroom, Pleurotus ostreatus, in Liquid Culture and its Cultivation Evaluation
Wei Rui ZHANG ; Sheng Rong LIU ; Yun Bo KUANG ; Shi Zhong ZHENG
Mycobiology 2019;47(1):97-104
Mushroom cultivation has gained increased attention in recent years. Currently, only four types of spawn, including sawdust spawn, grain spawn, liquid spawn, and stick spawn, are commonly available for mushroom cultivation. This limited spawn diversity has led to difficulty in selecting suitable inoculum materials in some cultivation. In this study, three small blocks of lignocellulosic agro-wastes and one block of a synthetic matrix were prepared as support for growing Pleurotus ostreatus in liquid medium. Mycelium-adsorbed blocks were then evaluated for their potential as block spawn for fructification. Our results indicated that the edible fungus was adsorbed and abundantly grew internally and externally on loofah sponge and synthetic polyurethane foam (PUF) supports and also has the ability to attach and grow on the surface of sugarcane bagasse and corncob supports. The mycelia of P. ostreatus adhered on corncob exhibited the highest metabolic activity, while those on the PUF showed the least activity. Mycelial extension rates of block spawns made of agro-waste materials were comparable to that of sawdust spawn, but the block spawn of PUF showed a significantly lower rate. No significant differences in cropping time and yield were observed among cultivations between experimental block spawns and sawdust spawns. Moreover, the corncob block spawn maintained its fruiting potential during an examined period of 6-month storage. The developed block spawn could be practically applied in mushroom cultivation.
Agaricales
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Fruit
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Fungi
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Luffa
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Pleurotus
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Polyurethanes
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Porifera
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Saccharum
6.Control of Anthracnose and Gray Mold in Pepper Plants Using Culture Extract of White-Rot Fungus and Active Compound Schizostatin
Swarnalee DUTTA ; E Eum WOO ; Sang Mi YU ; Rajalingam NAGENDRAN ; Bong Sik YUN ; Yong Hoon LEE
Mycobiology 2019;47(1):87-96
Fungi produce various secondary metabolites that have beneficial and harmful effects on other organisms. Those bioactive metabolites have been explored as potential medicinal and antimicrobial resources. However, the activities of the culture filtrate (CF) and metabolites of white-rot fungus (Schizophyllum commune) have been underexplored. In this study, we assayed the antimicrobial activities of CF obtained from white-rot fungus against various plant pathogens and evaluated its efficacy for controlling anthracnose and gray mold in pepper plants. The CF inhibited the mycelial growth of various fungal plant pathogens, but not of bacterial pathogens. Diluted concentrations of CF significantly suppressed the severity of anthracnose and gray mold in pepper fruits. Furthermore, the incidence of anthracnose in field conditions was reduced by treatment with a 12.5% dilution of CF. The active compound responsible for the antifungal and disease control activity was identified and verified as schizostatin. Our results indicate that the CF of white-rot fungus can be used as an eco-friendly natural product against fungal plant pathogens. Moreover, the compound, schizostatin could be used as a biochemical resource or precursor for development as a pesticide. To the best of our knowledge, this is the first report on the control of plant diseases using CF and active compound from white-rot fungus. We discussed the controversial antagonistic activity of schizostatin and believe that the CF of white-rot fungus or its active compound, schizostatin, could be used as a biochemical pesticide against fungal diseases such as anthracnose and gray mold in many vegetables.
Agaricales
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Fruit
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Fungi
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Incidence
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Plant Diseases
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Plants
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Vegetables
7.Genetic Diversity of the Pear Scab Fungus Venturia nashicola in Korea
Eu Ddeum CHOI ; Gyoung Hee KIM ; Sook Young PARK ; Jang Hoon SONG ; Young Sun LEE ; Jae Sung JUNG ; Young Jin KOH
Mycobiology 2019;47(1):76-86
Scab disease caused by Venturia nashicola is of agroeconomic importance in cultivation of Asian pear. However, little is known about the degree of genetic diversity in the populations of this pathogen. In this study, we collected 55 isolates from pear scab lesions in 13 major cultivation areas in Korea and examined the diversity using sequences of internal transcribed spacer (ITS) region, β-tubulin (TUB2), and translation elongation factor-1α (TEF-1α) genes as molecular markers. Despite a low level of overall sequence variation, we found three distinctive subgroups from phylogenetic analysis of combined ITS, TUB2, and TEF-1α sequences. Among the three subgroups, subgroup 1 (60% of isolates collected) was predominant compared to subgroup 2 (23.6%) or subgroup 3 (16.4%) and was distributed throughout Korea. To understand the genetic diversity among the subgroups, RAPD analysis was performed. The isolates yielded highly diverse amplicon patterns and none of the defined subgroups within the dendrogram were supported by bootstrap values greater than 30%. Moreover, there is no significant correlation between the geographical distribution and the subgroups defined by molecular phylogeny. Our data suggest a low level of genetic diversification among the populations of V. nashicola in Korea.
Asian Continental Ancestry Group
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Fungi
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Genetic Variation
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Humans
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Korea
;
Phylogeny
;
Pyrus
8.Alternaria yunnanensis sp. nov., a New Alternaria Species Causing Foliage Spot of Rubber Tree in China
Zhi Ying CAI ; Yi Xian LIU ; Yu Ping SHI ; Li Ming DAI ; Lan Lan LI ; Hong Jun MU ; Mei Lin LV ; Xiao Yong LIU
Mycobiology 2019;47(1):66-75
A new species of Alternaria causing leaf spots on the rubber tree (Hevea brasiliensis) in Yunnan, China, was isolated, examined, and illustrated. Morphologically, it belongs to the section Porri of Alternaria, which produces relatively large conidia and a simple or branched, filamentous long beak. It is, however, characterized by conidiophores gradually enlarging near the apex into a clavate conidiogenous cell and long ellipsoid to obclavate, smooth-walled conidia with a long filamentous beak. Molecular phylogenetic analyses based on ITS rDNA, GAPDH, and TEF1-alpha sequences demonstrate that the phytopathogen falls in the clade of the section Porri, being most closely related to A. sidae, A. sennae, A. deseriticola, A. cyamopsidis, A. rostellata, A. nitrimali, A. crassa, and A. thunbergiae.
Acanthaceae
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Accidental Falls
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Alternaria
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Animals
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Ascomycota
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Beak
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China
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Classification
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DNA, Ribosomal
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Hevea
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Rubber
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Spores, Fungal
9.An Enzymolysis-Assisted Agrobacterium tumefaciens-Mediated Transformation Method for the Yeast-Like Cells of Tremella fuciformis
Yuanyuan WANG ; Danyun XU ; Xueyan SUN ; Lisheng ZHENG ; Liguo CHEN ; Aimin MA
Mycobiology 2019;47(1):59-65
Agrobacterium tumefaciens-mediated transformation (ATMT), as a simple and versatile method, achieves successful transformation in the yeast-like cells (YLCs) of Tremella fuciformis with lower efficiency. Establishment of a more efficient transformation system of YLCs is important for functional genomics research and biotechnological application. In this study, an enzymolysis-assisted ATMT method was developed. The degradation degree of YLCs depends on the concentration and digestion time of Lywallzyme. Lower concentration (≤0.1%) of Lywallzyme was capable of formation of limited wounds on the surface of YLCs and has less influence on their growth. In addition, there is no significant difference of YLCs growth among groups treated with 0.1% Lywallzyme for different time. The binary vector pGEH under the control of T. fuciformis glyceraldehyde-3-phosphate dehydrogenase gene (gpd) promoter was utilized to transform the enzymolytic wounded YLCs with different concentrations and digestion time. The results of PCR, Southern blot, quantitative real-time PCR (qRT-PCR) and fluorescence microscopy revealed that the T-DNA was integrated into the YLCs genome, suggesting an efficient enzymolysis-assisted ATMT method of YLCs was established. The highest transformation frequency reached 1200 transformants per 106 YLCs by 0.05% (w/v) Lywallzyme digestion for 15 min, and the transformants were genetically stable. Compared with the mechanical wounding methods, enzymolytic wounding is thought to be a tender, safer and more effective method.
Agrobacterium
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Blotting, Southern
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Digestion
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Genome
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Genomics
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Methods
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Microscopy, Fluorescence
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Oxidoreductases
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Polymerase Chain Reaction
;
Real-Time Polymerase Chain Reaction
;
Wounds and Injuries
10.Fungal Diversity and Enzyme Activity Associated with the Macroalgae, Agarum clathratum
Seobihn LEE ; Myung Soo PARK ; Hanbyul LEE ; Jae Jin KIM ; John A EIMES ; Young Woon LIM
Mycobiology 2019;47(1):50-58
Agarum clathratum, a brown macroalgae species, has recently become a serious environmental problem on the coasts of Korea. In an effort to solve this problem, fungal diversity associated with decaying A. clathratum was investigated and related β-glucosidase and endoglucanase activities were described. A total of 233 fungal strains were isolated from A. clathratum at 15 sites and identified 89 species based on morphology and a multigene analysis using the internal transcribed spacer region (ITS) and protein-coding genes including actin (act), β-tubulin (benA), calmodulin (CaM), and translation elongation factor (tef1). Acremonium, Corollospora, and Penicillium were the dominant genera, and Acremonium fuci and Corollospora gracilis were the dominant species. Fifty-one species exhibited cellulase activity, with A. fuci, Alfaria terrestris, Hypoxylon perforatum, P. madriti, and Pleosporales sp. Five showing the highest enzyme activities. Further enzyme quantification confirmed that these species had higher cellulase activity than P. crysogenum, a fungal species described in previous studies. This study lays the groundwork for bioremediation using fungi to remove decaying seaweed from populated areas and provides important background for potential industrial applications of environmentally friendly processes.
Acremonium
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Actins
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Biodegradation, Environmental
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Calmodulin
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Cellulase
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Fungi
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Korea
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Penicillium
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Peptide Elongation Factors
;
Seaweed