• The Korean Journal of Mycology
• /
• v.47 no.4
• /
• pp.319-328
• /
• 2019

As an effort to explore fungal diversity, fungal survey was undertaken in 2018 in Jangheung, Korea. For the survey, medicinal plant leaves were sampled from Selaginella tamariscina, Serratula coronata ssp. insularis, Scutellaria baicalensis, Scrophularia buergeriana and subjected to fungal isolation. Four unrecorded fungal species, Paraboeremia selaginellae, Colletotrichum camelliae, Alternaria eichhorniae, and Phomopsis capsici were obtained from the survey. This study described their morphological characteristics including colony features formed on media, light microscopic images and molecular characteristics of nucleotide sequences of the ITS and 28S rDNA regions.

• Research in Plant Disease
• /
• v.9 no.3
• /
• pp.153-158
• /
• 2003

Mycological characteristics of Phomopsis citri isolates obtained from blighted twigs of citrus cultivation areas in Jeju island were all identified as Phomopsis citri known as the anamorph stage of Diaporthe citri. Pycnidia the isolates sized from 112.2 to 614.4${\mu}m$ (av. 328.8${\mu}m$) and shaped conical to lenticulata in black. Two types of phialospores, ${\alpha}$-and ${\beta}$-spores were observed from pycnidia. The ${\alpha}$-spores were hyaline, unicellula, fusiform to ellipsoidal and sized 4.7~8.7 1.9 ${\times}$ 3.5${\mu}m$ (av. 6.7 ${\times}$ 2.3 ${\mu}m$). The ${\beta}$-spores were hyaline, unicellula, filiform, curved and often strongly hooked and sized 13.2~27.1 ${\times}$ 0.8~1.6 ${\mu}m$ (av. 22.1 ${\times}$ 1.0 ${\mu}m$). All isolates grew well and produced abundant pycnidia and spore horns on PDA. In addition, all isolates showed strong pathogenicity to citrus fruit inducing melanose symptoms when artificially inoculated with the pycnidial spores.

• Research in Plant Disease
• /
• v.7 no.2
• /
• pp.107-111
• /
• 2001

Deterioration of pod and seed quality by pod and stem blight and purple blotch is a serious problem in the production of vegetable soybean. Major inoculum sources for the causal pathogens, Phomopsis spp. and Cercospora kikuchii, are soybean straw and debris. Phomopsis spp. have been known to be either limited for hyphal growth or latent in immature soybean tissues. In this experiment, cultural practices using these ecological traits of the pathogens were applied as a control measure. In plastic mulching, seed infection was remark ably reduced by drip irrigation as compared to overhead sprinkling, but not reduced in no mulching cultivation. Control value of plastic mulching was 28.0% for pod and stem blight and 29.3% for purple blotch, which was lower than that of benomyl application. By the first week in June, 78% of overwintered soybean straw examined contained matured alpha spores in pycnidia, acting as primary inoculum. Secondary inoculum of phomopsix spp. was observed abundantly throughout from mid June to September on fallen cotyledons from current crops and subsequently was found on petiole debris. Consequently, both plastic mulching and drip irrigation were effective to some extent for controlling pod and stem blight and purple blotch without significant reduction in soybean yield, and the cultural practices in combination with field sanitation resulted in removing more the secondary inoculum.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.54 no.1
• /
• pp.104-118
• /
• 2009

This study was carried out to classify Korean soybean varieties base on maturity group (MG) and to find character relationships according to planting date for high quality soybean seed production adapted to early season cultivation environment of Miryang. Results of maturity grouping of Korean soybean varieties showed that Keunol (3 cultivars), belonged to Group 0; Seonnok and Danmi in Group II, Shinrok in Group III, Seonyu (17 cultivars), in Group IV, Taekwang (44 cultivars) in Group V, Daewon (25 cultivars) in Group VI, and Kwangdu and Keumdu in Group VII. Agronomic characteristics of 100 soybean varieties were compared based on MG, cultivation year and seeding date. Soybean varieties belonging to the MG $VI{\sim}VII$ showed longer days to flowering and growth period, high lodging density and higher yield. Seed quality analysis revealed that as maturity was delayed, seed weight becomes heavier while seed cracks become abundant. In addition, occurrence of purple seed and phomopsis were higher in MG $0{\sim}III$. Protein content was higher in MG $0{\sim}III$, and isoflavone content was higher as maturity was delayed. On the other hand, lipid content was generally similar across MGs. Correlation analysis of major agronomic characters showed positive relationships between days to flowering and growth days, seed weight and lodging in MG $IV{\sim}V$, seed crack and growth days in MG $0{\sim}III$, seed crack and days to flowering in MG $IV{\sim}V$ and MG $VI{\sim}VII$, seed crack and lodging in MG $IV{\sim}V$ and MG $VI{\sim}VII$, seed crack and seed weight in MG $IV{\sim}V$ and MG $VI{\sim}VII$, purple seed and growth days in MG $IV{\sim}V$, purple seed and seed weight in MG $VI{\sim}VII$, phomopsis and growth days in MG $IV{\sim}V$ and MG $VI{\sim}VII$, and phomopsis and purple seed in MG $IV{\sim}V$ and MG $VI{\sim}VII$. In contrast, a negative relationship was observed between seed weight and lodging in MG $0{\sim}III$. Correlating yield and major characters revealed negative relationships between days to flowering and growth days in MG $0{\sim}III$ and MG $IV{\sim}V$, whereas positive relationships were obtained on MG $VI{\sim}VII$ seeded on April 30. Lodging, seed weight and seed crack were all negatively correlated with yield in the MG $IV{\sim}V$ and MG $VI{\sim}VII$. Soybean cultivars identified as adaptable to early season planting for production of high quality soy curd and fermented soybean paste were Seonyu, Kwangdu, and Soho while those suited for the manufacture of soybean sprouts were Sobaeknanul, Kwangan, Sowon, and Bosuk. Geomjeong 2 chosen as best for mixing with rice.

• The Plant Pathology Journal
• /
• v.31 no.3
• /
• pp.290-298
• /
• 2015

Starting in 2012, severe diebacks usually accompanied by abundant gum exudation have occurred on yuzu trees in Goheung-gun, Jeonnam Province, where severely affected trees were occasionally killed. On-farm surveys were conducted at 30 randomly-selected orchards located at Pungyang-myeon, Goheung-gun, and the resulting disease incidences were 18.5% and 39.6% for dieback and gumming symptoms, respectively. Black spots on branches and leaves also appeared on infected trees showing a typical dieback symptom. Morphological and molecular identifications of the isolated fungal organisms from lesions on the symptomatic leaves and branches revealed that they are identical to Phomopsis citri, known to cause gummosis. In order to find the reason for this sudden epidemic, we investigated the weather conditions that are exclusively distinct from previous years, hypothesizing that certain weather extremes might have caused the severe induction of pre-existing disease for yuzu. There were two extreme temperature drops beyond the yuzu's cold hardiness limit right after an abnormally-warm-temperature-rise during the winter of 2011-12, which could cause severe frost damage resulting in mechanical injuries and physiological weakness to the affected trees. Furthermore, there was an increased frequency of strong wind events, seven times in 2012 compared to only a few times in the previous years, that could also lead to extensive injuries on branches. In conclusion, we estimated that the possible damages by severe frost and frequent strong wind events during 2012 could cause the yuzu trees to be vulnerable to subsequent fungal infection by providing physical entries and increasing plant susceptibility to infections.

• The Plant Pathology Journal
• /
• v.28 no.1
• /
• pp.55-59
• /
• 2012

Northern stem canker caused by $Diaporthe$ $phaseolorum$ var. $caulivora$ ($Dpc$) has become a serious disease in soybean. The objectives of this study were to survey the existence of $Dpc$ on soybean in Korea, and to examine the potential pathogenicity of $Dpc$ in seed decay. One such isolate, SSLP-4, isolated from a field-grown plant of the Korean soybean cultivar Danbaekkong, was identified as $Dpc$, based on its morphological and molecular characteristics by sequences of internal transcribed spacer (ITS), translation elongation factor (TEF) 1-${\alpha}$ and ${\beta}$-tubulin regions, as well as pathogenic analyses. Moreover, morphological and molecular analyses revealed that isolate SSLP-4 was nearly identical to $Dpc$ strains from the United States. Pathogenicity tests on hypocotyls of soybean seedlings and detached leaves resulted in typical symptoms of soybean northern stem canker and inoculation on plants at R5-R7 stage caused seed decay. All results suggest that the $Dpc$ strain SSLP-4 can cause both stem canker and seed decay on soybean. Thus, the SSLP-4 isolate has the potential to contribute greatly to understanding of host plant resistance mechanisms, both at vegetative and reproductive growth stages in soybean.

• The Korean Journal of Mycology
• /
• v.44 no.4
• /
• pp.252-258
• /
• 2016

In this study, endophytic fungi were isolated from the leaves of five species of woody plants in Jeju, Korea, namely Chamaecyparis obtusa, Cryptomeria japonica, Torreya nucifera, Ilex crenata, and Camellia japonica. The isolated fungal endophytes were identified based on their morphological and molecular characteristics including a sequence analysis of the internal transcribed spacer and 26S regions of rDNA and ${\beta}$-tubulin genes. Ten species of fungal endophytes have not been previously reported in Korea, namely Mycosphaerella aleuritidis, Neofusicoccum eucalyptorum, Neofusicoccum parvum, Phyllosticta citrichinensis, Phyllosticta cryptomeriae, Phomopsis cotoneastri, Sphaerulina rhododendricola, Guignardia mangiferae, Lophodermium jiangnanense, and Lophodermium minus.

• Food Science and Preservation
• /
• v.9 no.2
• /
• pp.131-136
• /
• 2002

Quality changes of satsuma mandarin (Citrus unshiu Marc. var. miyagawa) during storage by storage warehouse were investigated. Citrus were treated with 2000-folds diluted iminoctadime-triacetate solution and 1.5% chitosan with 0.5% CaCl$_2$ solution, and were at 30$\^{C}$ for 24 hr before storage. The citrus of about 12kg/26L plastic container were stored at room temperature, and at 4$\^{C}$ with 87% relative humidity. Decay ratio of citrus with precise temperature and humidity control were lower than the others during storage. Penicillium italicum Monilia candida Alternara citri, Mucor hiemalis, Phomopsis citri Botrytis cinerea, Phoma citricarpa Clomererella cingulata, Penicillium digitatum were identified as putrefactive microorganisms in citrus storage. Weight loss, moisture content of peel and flesh were decreased slowly during storage. 24% of original acid content were decreased at room temperature on 120 days storage, compared to 15∼18% loss on cold storage. Total sugar of citrus was decreased rapidly after 90 days, and vitamin C content were also decreased rapidly after 60 days during storage.

• Korean Journal of Food Science and Technology
• /
• v.28 no.6
• /
• pp.1142-1145
• /
• 1996

Long term-storage of citrus oranges after harvest has been hindered mainly by molds The goal of this research was to collect and identify those molds, which would help find a way to extend shelf-life after harvest. During the period of 1994 to 1995, fourteen different strains were isolated and purified from putrefied fruit (Citrus unshiu var.) that was stored at room temperature under open air. The storage disease was caused by the following molds: Penicillium italicum, 25.8%, Monilia candida, 19.8%; Alternaria citri, 18.1%; Mucor hiemalis, 11.0%; Phomopsis citri, 6.6%; Botrytis cinerea. 5.5%; Phoma citricarpa, 3.8%; Glomerella cingulata, 3.8%; P. digitatum, 1.1%; other molds, 4.5%; Most of the strains showed pectinolytic activity and putrefaction. These citrus fruit-putrefying molds will be used as target strains for the control of microorganisms during post-harvest storage.

• Journal of Microbiology and Biotechnology
• /
• v.31 no.4
• /
• pp.493-500
• /
• 2021

Endophytic fungi are symbiotically related to plants and spend most of their life cycle within them. In nature, they have a crucial role in plant micro-ecosystem. They are harnessed for their bioactive compounds to counter human health problems and diseases. Endophytic Diaporthe sp. is a widely distributed fungal genus that has garnered much interest within the scientific community. A substantial number of secondary metabolites have been detected from Diaporthe sp. inhabited in various plants. As such, this minireview highlights the potential of Diaporthe sp. as a rich source of bioactive compounds by emphasizing on their diverse chemical entities and potent biological properties. The bioactive compounds produced are of significant importance to act as new lead compounds for drug discovery and development.