1.First Report of Black Spot Disease Caused by Alternaria alternata on Sweet Persimmon Fruits.
Jung Han LEE ; Jinwoo KIM ; Youn Sig KWAK
Mycobiology 2013;41(3):167-169
Black spot of sweet persimmon, caused by Alternaria alternata, occurred in an orchard in Gyeongnam province, Korea in 2012. The symptom was appearance of 0.5 to 4 cm black spots on the surface of fruit. The pathogen was isolated from flesh of disease lesions. The causal agent was identified as A. alternata by morphological characteristics and sequencers of the internal transcribed spacer (ITS) 1 and ITS4 regions of rRNA. Artificial inoculation of the pathogen resulted in development of disease symptoms and the re-isolated pathogen showed characteristics of A. alternata.
Alternaria*
;
Diospyros*
;
Fruit*
;
Korea
2.Erratum: Taxonomic Studies on Alternaria in Korea (1).
Hye Sun CHO ; Byung Ryun KIM ; Seung Hun YU
Mycobiology 2001;29(2):120-120
Page 31. The size of conidia of Alternatia brassicicola should be 20~80x8~25 microm instead of 20~120x8~30 microm.
Alternaria*
;
Korea*
;
Spores, Fungal
3.Occurrence of Alternaria cassiae in Seeds of Sickle Senna in Korea.
Ik Hwa HYUN ; Hye Sun CHO ; Seung Hun YU
Mycobiology 2001;29(2):104-106
Alternaria cassiae Jurair & Khan was recorded on seeds of sickle senna(Cassia tora L.). Seed infection ranged from 25~45% in two samples. Developing roots and shoots turn brown and died in case of severe infection. Detailed descriptions were given on the habit characters of the fungus and on the morphology of conidiophores and condia. This is the first report of A. cassiae on seeds of Cassia.
Alternaria*
;
Cassia*
;
Fungi
;
Korea*
4.Excellent appearance of Dao-di Ginseng Radix et Rhizoma and interaction mechanism between genetic and environmental factors: a review.
Hong-Hong JIAO ; Lu-Qi HUANG ; Yuan YUAN
China Journal of Chinese Materia Medica 2023;48(12):3125-3131
Dao-di medicinal materials produced in a specific environment always present excellent appearance and high quality. Because of the unique appearance, Ginseng Radix et Rhizoma is regarded as a paradigm in the research on excellent appearance. This paper systematically summarized the research progress in the genetic and environmental factors influencing the formation of the excellent appearance of Ginseng Radix et Rhizoma, aiming to provide reference for the quality improvement of Ginseng Radix et Rhizoma and the scientific connotation of Dao-di Chinese medicinal materials. The Ginseng Radix et Rhizoma with high quality generally has a robust and long rhizome, a large angle between branch roots, and the simultaneous presence of a robust basal part of rhizome, adventitious roots, rhizome bark with circular wrinkles, and fibrous roots with pearl points. The cultivated and wild Ginseng Radix et Rhizoma have significant differences in the appearance and no significant difference in the population genetic diversity. The differences in the appearance are associated with cell wall modification, transcriptional regulation of genes involved in plant hormone transduction, DNA methylation, and miRNA regulation. The rhizosphere soil microorganisms including Fusarium and Alternaria, as well as the endophytes Trichoderma hamatum and Nectria haematococca, may be the key microorganisms affecting the growth and development of Panax ginseng. Cultivation mode, variety, and root exudates may be the main factors influencing the stability of rhizosphere microbial community. Ginsenosides may be involved in the formation of the excellent appearance. However, most of the available studies focus on the partial or single factors in the formation of Dao-di medicinal materials, ignoring the relationship within the complex ecosystems, which limits the research on the formation mechanism of Dao-di medicinal materials. In the future, the experimental models for the research involving genetic and environmental factors should be established and mutant materials should be developed to clarify the internal relationship between factors and provide scientific support for the research on Dao-di medicinal materials.
Alternaria
;
Microbiota
;
Panax/genetics*
;
Rhizome
5.A Novel Alternaria Species Isolated from Peucedanum japonicum in Korea.
Jian Xin DENG ; Hye Sun CHO ; Narayan Chandra PAUL ; Hyang Burm LEE ; Seung Hun YU
Mycobiology 2014;42(1):12-16
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.
Alternaria*
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Brassica
;
Classification
;
Fungi
;
Korea
6.Identification, biological characteristics, and fungicide screening of pathogen of black spot in Aconitum carmichaelii.
Jia ZHOU ; Tie-Lin WANG ; Yu-Huan MIAO ; Da-Hui LIU
China Journal of Chinese Materia Medica 2022;47(5):1215-1221
In Hezhang county, Guizhou province, black spot tends to occur to Aconitum carmichaelii in the hot rainy summer, with the incidence up to 50%-70%, seriously impacting the yield and quality of the medicinal material. Thus, this study aims to clarify the pathogen and the occurrence characteristics. To be specific, the pathogen was isolated and identified according to Koch's postulates and the pathogenicity and biological characteristics were determined. In addition, the sensitivity of the pathogen to four microbial fungicides, four botanical fungicides, and five chemical fungicides was determined with the mycelium growth rate method for the purpose of screening out optimal fungicides. The pathogen was identified as Alternaria alternate, as evidenced by the similar colony morphology and microscopic characteristics and 99.55%-100% similarity in sequences of rDNA-ITS, LSU, 18S, and TEF of the two. The optimum growth conditions for A. alternata were 28 ℃, pH 8, and continuous darkness. Bacillus subtilis had strong inhibitory effect on the pathogen, and the inhibition rate was more than 90% when the concentration was 1 mg·L~(-1). In addition, difenoconazole and quinoline copper can also control the pathogen, with median effective concentration(EC_(50)) of 2.92 and 9.02 mg·L~(-1), respectively. This study lays a theoretical basis for the field control of black spot in A. carmichaelii.
Aconitum
;
Alternaria
;
Fungicides, Industrial/pharmacology*
;
Mycelium
7.Identification and biological characterization of pathogen causing black spot of Pseudostellaria heterophylla in Fujian province.
Wu-Jun ZHANG ; Bao-Cai LIU ; Jing-Ying CHEN ; Ying-Zhen HUANG ; Yun-Qing ZHAO ; Jing-Rong CAI
China Journal of Chinese Materia Medica 2023;48(10):2732-2738
In Zherong county, Fujian province, the black spot of Pseudostellaria heterophylla often breaks out in the rainy season from April to June every year. As one of the main leaf diseases of P. heterophylla, black spot seriously affects the yield and quality of the medicinal material. To identify and characterize the pathogens causing black spot, we isolated the pathogens, identified them as a species of Alternaria according to Koch's postulates, and then tested their pathogenicity and biological characteristics. The results showed that the pathogens causing P. heterophylla black spot were A. gaisen, as evidenced by the similar colony morphology, spore characteristics, sporulation phenotype, and the same clade with A. gaisen on the phylogenetic tree(the maximum likelihood support rate of 100% and the Bayesian posterior probability of 1.00) built based on the tandem sequences of ITS, tef1, gapdh, endoPG, Alta1, OPA10-2, and KOG1077. The optimum conditions for mycelial growth of the pathogen were 25 ℃, pH 5-8, and 24 h dark culture. The lethal conditions for mycelia and spores were both treatment at 50 ℃ for 10 min. We reported for the first time the A. gaisen-caused black spot of P. heterophylla. The results could provide a theoretical basis for the diagnosis and control of P. heterophylla leaf spot diseases.
Bayes Theorem
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Phylogeny
;
Caryophyllaceae
;
Alternaria
;
Mycelium
8.Biological Control of Alternaria Fruit Rot of Chili by Trichoderma Species under Field Conditions.
Most Ferdousi BEGUM ; M A RAHMAN ; M Firoz ALAM
Mycobiology 2010;38(2):113-117
Trichoderma strains were evaluated under field conditions to assay their efficacy in suppressing Alternaria fruit rot disease and promoting chili plant growth. The experiment was conducted at the Botanical Garden, Rajshahi University, Bangladesh from July 2006 to March 2007. Application of Trichoderma harzianum IMI 392432 significantly (p = 0.05) suppressed the disease compared to Alternaria tenuis (T2) treatment and improved both growth and yield. The treatment T4 (T. harzianum IMI-392432 + A. tenuis) was most effective in reducing disease percentage (72.27%) compared to A. tenuis (T1) treatment. The highest seed germination rate (85.56%) and the highest growth and yield (12.5 g/plant) was also recorded in the same treatment (T4), followed by T5 (T. harzianum IMI-392433 000000 + A. tenuis), T6 (T. harzianum IMI-392434 +A. tenuis), T2 (T. virens IMI-392430 + A. tenuis), and T3 (T. pseudokoningii IMI-392431 +A. tenuis) treatment, while single treatment with A. tenuis significantly decreased these values.
Alternaria
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Bangladesh
;
Fruit
;
Germination
;
Plants
;
Seeds
;
Trichoderma
9.Biological Control of Some Serious Weeds in Dakahlia District. II. Mycoherbicial Production and Physiological Host Responses.
Mycobiology 2002;30(2):96-101
Four pathogenic fungal isolates belonging to different genera including Alternaria, Fusarium and Curvularia were isolated from selected diseased weeds growing in the fields in Dakahalia district. The inoculum of these pathogenic fungi specific to weeds were cultured, standardized and formulated as alginate pellets containing mycelium plus culture filtrate. These mycoherbicides were evaluated for disease severity (DS). Maximum DS was obtained with the alginate pellets of mycelium filtrate Fusarium solani. Physiological changes of the treated weed were determined 5 and 10 days after treatments. As compared to the healthy weeds, all mycoherbicide formulations significantly decreased the amount of photosynthetic pigments and subsequently soluble and insoluble sugars in the infected weeds. The mycoherbicide formulation of F. solani had the greatest effect on lowering to the abovementioned amount in the leaves of Chenopodium murale. Generally, treatment of weed leaves with the specific mycoherbicide led to a highly significant increase in total phenol content when compared to the healthy control weed. C. murale infected with the mycoherbicide formulation of F. solani had higher levels of phenolic compounds than those other treated weeds particularly after 10 days of inoculation.
Alternaria
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Carbohydrates
;
Chenopodium
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Fungi
;
Fusarium
;
Mycelium
;
Phenol
10.Diversity and Bioactive Potential of Culturable Fungal Endophytes of Medicinal Shrub Berberis aristata DC.: A First Report.
Supriya SHARMA ; Suruchi GUPTA ; Manoj K DHAR ; Sanjana KAUL
Mycobiology 2018;46(4):370-381
Bioactive natural compounds, isolated from fungal endophytes, play a promising role in the search for novel drugs. They are an inspiring source for researchers due to their enormous structural diversity and complexity. During the present study fungal endophytes were isolated from a well-known medicinal shrub, Berberis aristata DC. and were explored for their antagonistic and antioxidant potential. B. aristata, an important medicinal shrub with remarkable pharmacological properties, is native to Northern Himalayan region. A total of 131 endophytic fungal isolates belonging to eighteen species and nine genera were obtained from three hundred and thirty surface sterilized segments of different tissues of B. aristata. The isolated fungi were classified on the basis of morphological and molecular analysis. Diversity and species richness was found to be higher in leaf tissues as compared to root and stem. Antibacterial activity demonstrated that the crude ethyl acetate extract of 80% isolates exhibited significant results against one or more bacterial pathogens. Ethyl acetate extract of Alternaria macrospora was found to have potential antibacterial activity. Significant antioxidant activity was also found in crude ethyl acetate extracts of Alternaria alternata and Aspergillus flavus. Similarly, antagonistic activity of the fungal endophytes revealed that all antagonists possessed inhibition potential against more than one fungal pathogen. This study is an important step towards tapping endophytic fungal diversity for bioactive metabolites which could be a step forward towards development of novel therapeutic agents.
Alternaria
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Aspergillus flavus
;
Berberis*
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Endophytes*
;
Fungi