• Korean Journal Plant Pathology
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• v.3 no.2
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• pp.114-119
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• 1987

Banana blast was frequently encountered in greenhouses of Jeju province during a local survey of plan diseases from 1985 to 1986. The disease incidence on banana was very severe up to $100\%$ in a greenhouse. The causal fungus was identified as Pyricularia angulata Hashioka based on mycological characteristics and Path genicity of the fungus. The symptom of blast produced on leaves of banana was circular to oval, dark brow spots with yellow margins which measured 1-10mm in diameter, and the symptom on fruits was circular to oval reddish brown or dark brown, depressed spots which measured up to 20mm in diameter. The symptoms were scattered not only on leaves and fruits of banana but. also on petioles, leaf sheaths, bunch stalks and crowns The pathogen was characterized that conidia were hyaline, 2 septated, ovate to pyriform with a small hilum solitary at ends of den tides of conidiophores, and measured $16.0-34.0\times7.0-12.0{\mu}m$ (average $22.5\times9.0{\mu}m$) and conidiophores were mostly 2 septated, occasionally 2 or 3 branched, denticulate at the tips, and measured $7.5-100.0\times3.0-5.0{\mu}m$(average $90.0\times4.0{\mu}m$). The optimum temperature range for mycelial growth of the fungus on PDA was $26-28^{\circ}C$. The result of pathogenicity tests revealed that P. angulata had pathogenicity only on banana. On the other hand Pyricularia grisea (Cke.) Sacc. isolated from Digitaria sanguinalis(L.) Scopo. was not pathogenic to banana. It was revealed that the leaves were the most susceptible to P. angulata among several parts of banana in inoculation tests. Thirty-day-old fruits of banana were more susceptible to the fungus than 60-day-old fruits, and bunch stalks were more susceptible than the fruits.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.55-55
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• 2019

Strawberry which is the genus Fragaria under family Rosaceae is one of the most important fruit plants for both fresh consumption and food processing in the temperate and subtropical countries. Propagation of strawberry is achieved either through runners or by in vitro micropropagation. Meristem tips, generally obtained from runners of virus-free plants, are commonly used to establish in vitro cultures, which are employed for mass propagation or as a source of plant material for regeneration and transformation experiments. This study was conducted to determine the optimal natural additives strength to improve sprouting shoot rate of apical meristem of strawberry 'Seolhyang'. Strawberry apical meristem at size (0.2 mm to 0.3 mm) with leaf primordials were cultured on the 1/3MS(Murashige & Skoog) medium supplemented with five natural additives such as coconut milk, maple sap, banana powder and peptone. The sprouting ratio and growth characteristics were evaluated after eight weeks after in vitro culture. Shoot ratio of 'Seolhyang' apical meristem was 72.9% in 1/3MS medium supplemented with maple sap. On the other hand, the low shoot ratio was observed 47.7% in 1/3MS medium supplemented with banana powder. Shoot length was different as natural additives but numbers of leaf was not significantiy different among the natural additives. As a result, the sprouting ratio and plant growth were enhanced effectively in 1/3MS medium with maple sap compared to the others.

• Journal of Plant Biotechnology
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• v.45 no.2
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• pp.140-145
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• 2018

Inducing genetic and morphological variation through conventional method is very difficult. Therefore, mutation induction through in vitro technology brings numerous advantages over the conventional breeding. Thus, the individual shoots (1 ~ 2 cm) were irradiated with gamma rays (10 ~ 70 Gy). The result revealed that the explants treated with higher doses (40, 50, 60, and 70 Gy) showed deleterious effects of ionizing radiation. The highest survival rate among ${\gamma}$ treated explants recorded was 71% in 10 Gy treatments while the lowest survivality was 15% in 70 Gy. Lethal dose 50% ($LD_{50}$) dose was found to be 33 Gy. In the in vitro condition, rooting reponse showed that increase in gamma irradiation dose resulted in the inhibition of root growth. Meanwhile, non-treated explants had the best rooting ability with the maximum number of root per explant (20) within a short period of time (6 days), with the highest root length of (15.1 cm). The longer period in rooting (12 days) and lowest number of root per explant (8) with shortest root length (10.1 cm) were recorded at 30 Gy treatment. The highest shoot length (13.6 cm) was observed at control treatment and the shortest shoot length (10.4 cm) was observed at 30 Gy. In the nursery, lowest leaf number (5) was observed at 30 Gy compared with other treatments. The highest chlorophyll content (49.8) was recorded at 10 Gy treated seedling. Irradiated explants with 10 Gy found to be superior over the control treatment and had positive effects in main growth parameters such as chlorophyll content.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2005.06a
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• pp.245-247
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• 2005

A cellulolytic fungus isolated from Agave plantation in northeastern Thailand was identified as Acrophialophora nainiana. The fungus was capable of growing at pH between 3 - 7 and 25 - 45 $^{\circ}C$, with the optimum conditions at pH 5.0 and 40 $^{\circ}C$. The wild isolate produced cellulases, comprising of exoglucanase (0.019 U/mg protein), endoglucanase (0.366 U/mg protein), and ${\beta}$-glucosidase (0.001 U/mg protein). Mutations with UV and NTG produced the UV 10-2 mutant with cellulases activities including exoglucanase (0.093 U/mg protein), endoglucanase (0.585 U/mg protein), and ${\beta}$-glucosidase (0.013 U/mg protein). Purification of the enzymes with ultrafiltration, ammonium sulfate precipitation, and ion-exchange chromatography yielded the maximal cellulase specific activities of 2.736 U/mg protein (exoglucanase), 0.235 U/mg protein (endoglucanase), and 0.008 U/mg protein (${\beta}$-glucosidase). The mutant's cellulases were the most active at pH 5.0 and 60 $^{\circ}C$. Ion-exchange chromatography revealed that A. nainiana UV 10-2 cellulases were comprised of two peaks with one peak showing the single endoglucanase activity while the other peak showed a mixture of the three enzyme activities. Production of A. nainiana UV 10-2 cellulases using banana leaf stalk as the sole carbon source gave comparable yields to that of the pure ${\alpha}$-cellulose. The enzymes were used in the simultaneous saccharification and fermentation (SSF) of plant residue (Coix aquatica) along with Kluveromyces marxianus to produce ethanol. Moreover, when the enzymes were used in the bioscouring process of fabric, the desiravle traits of textile processing including immediate water absorbency, increased in whiteness and reduction of yellowness of the treated fabric were observed.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.408-412
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• 1998

In order to illustrate the role of conidia of Mycosphaerella nawae as a secondary inoculum in nature, pseudothecial development on persimmon leaves was investigated microscopically. The fungal ascospores have been believed as the primary or only inoculum source in nature, however, pseudothecia were readily formed on persimmon leaves infected naturally and artificially by conidia. The pseudothecia of M. nawae were found to form in the tissues of infected leaves while the leaves were still hanging on the trees. The size of pseudothecia were approximately 51.0~122.4$\times$51.0~112.2 ${\mu}{\textrm}{m}$ (82.8 $\times$72.5 ${\mu}{\textrm}{m}$in average), the shapes were spherical, ovoid or occidental pear type. The sizes of asci were approximately 30.6~61.2$\times$8.2~10.2 ${\mu}{\textrm}{m}$(46.6$\times$9.4 ${\mu}{\textrm}{m}$ in average) and the shapes were cylinder or banana. The ascospores were mostly spindle type, and the sizes were 10.2~12.2$\times$3.1~4.1 ${\mu}{\textrm}{m}$ (11.4$\times$3.2 ${\mu}{\textrm}{m}$ in average)-like. The pseudothecial formation was initiated before defoliation and morphological characteristics of the pseudothecia, ascus and ascospores on the infected leaves were fully illustrated in this study. Results indicated that conidia of M. nawae induce circular leaf spot of persimmon as much as ascospores, and might play an important role of the disease epidemics in nature.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.1
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• pp.55-63
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• 1999

This research was conducted to estimate waste rates of 69 food items after pre-preparation and amounts of food wastes disposed and it's reduction effect by education in some institutional foodservices for reduction of the food wastes. The result are as follows: 1. The waste rates were 55.40% for sweet corn, 5.73% for potatoes, 19.14% for sweet potatoes, and 33.47% for chestnuts. 2. The waste rates of fruits were 0.21-49.36%. Food items with over 40% waste rate were banana, watermelon, and pineapple. 3. The waste rates of vegetables were 1.14-52.90%. The number of foods with under 10% waste rate were 14 items(red pepper, green pepper, chard, and so on), 10-20% was 9 items(perilla leaf, chinese cabbage, ginger root, and so on), 20-30% was 5 items(root of chinese bellflower, garlic, radish-leaves, burdock, welsh onion-large type), 30-40% was 3 items(shepherd's purse, head lettuce, kale) and over 40% was 3 items(water dropwort, crown daisy, mallow). 4. The waste rates were 24.30% in chicken, 9.53-13.79% in eggs, and 9.30-55.32% in fishes. The waste rates of vegetables and fishes were higher than those of other food groups. 5. There were significantly different in amount of food wastes disposed (g/person/day) to institutional foodservices (hospital＞industrial institution＞ Korean restaurant＞elementary school). The amount of food wastes disposed, especially amount in pre-preparation phase, after education for reduction of food wastes was significantly reduced. Since these study results show significant deviations in food waste rates and education effect, there should be more studies for standard waste rates of each food and systematic education method for reduction of food wastes.

• Journal of Plant Biology
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• v.3 no.2
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• pp.29-34
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• 1960

From the view point of phytopathological anatomy, the author has tried to study the effect of the shoot cluster disease virus on the internal structure of vascular tissues of chinese date tree (Ziziphus jujuba var. inermis Rehd.) comparing healthy checks and diseased plants. The materials were collected at the several sites, Kumgock-Ri, Masuc-Ri, Kyungi-Do, and near the campus of Korea University and around the area of Chongam-Dong, Seoul City, from August 15th to September 5th 1959. The leaf materials of healthy and diseased plants are fixed and aspirated in two kinds of killing solutions, formalin-acetic acid alcohol solution and Craf III solution. Sections were cut at 5-10$\mu$ thickness and stained with the double staining reagents of safranin and fast green. In this experiment the author has observed that there are marked structural changes in the infected plants in contrast of healthy checks. As figures 3-7 show that the following characteric changes have taken place on infected plants: 1) the arrangement of irregularly developed sieve elements in phloem, 2) the degeneration of phloem elements, 3) the irregular arrangement of epidermis in mid-vein, 4) more necrosis is observed among the parenchymatous cells, 5) abundant accumulatin of starch grains in parenchymatous cells, . In contrast to the above irregularities caused by the virus disease, the healthy checks appear normal structures as shown in figures 1 and 2. In adding to the all features noted above, the author could also observe an interesting feature that the xylem elements in mid-vein vascular bundle tissues are considerably disorganized to show the unspecialized vessel elements, the irregularly arranged xylem elements. However, this kind of irregularities which occur in xylem under the virus infection has not been reported previously. The features noted on the internal structure of vascular bundle under the condition of infection by the shoot cluster disease on chinese date trees appear to be more or less closely similar to the symptoms of the bunchy-top of banana and the yellow dwarf disease of barley in respect to the fact that whether phloem necrosis takes place as a primary symptom or a secondary symptom. In all these disease, primary histological changes of hypoplasia and hypertrophy are preceeded by the necrosis of phloem.

• Korean journal of applied entomology
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• v.33 no.2
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• pp.60-65
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• 1994

This study was carried out to investigate the ecology of Nesodiprion japonlcus (Mmm,m) damaging many conifers The results obtained were as follows: Nesod~prion japonicus (Maun) emerged two times for a year and their body was black m both sexes. A female (10.1t 1 2 mm) adult was larger than a male (9.9t 0.8 mm) one in the body size. The size of antenna as plumose of female was different from that of male. Life span of adults was 3 or 4 days, those emergence rate was 92% and sex ratio of female to male was 6: 4. Adults 1a1d only an egg in the leaf and the region of the leaf aviposited turned brown. Duration of egg was 14.35 1 2 days, egg was In the shape of banana and red~sh-yellow,a nd its sire was 2.4+ 0.2 mm long. Duration of larvae was 30.35 2.1 days and its slze 20.15 2.2 mm, body was green with grey~sh shipes on the dorsal and lateral aspect, the tip of front and hind was yellow and head was brown with a dark-p~gmented area. Mature larva turned into light green and get lost a dark-pigmented area of head. The firstly-emerged larva made cocoons on the base of leaves and the secondawemerged larva among fallen leaves Duration of prepupa was 14.3f 2.0 days and their size 10.15 2.3 mm Duration of pupa was 12.2+ 1.3 days and its size 10.lt0.2mm.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1335-1339
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• 2010

A total of 550 samples were analysed for nitrate contents using HPLC-UV. Nitrate contents of leaf vegetables were higher than those of root vegetables and fruit vegetables. The average nitrate content of the radish leaves (4875.8 mg/kg) was the highest, followed by marsh mallow (4711.7 mg/kg), crown daisy (4546.9 mg/kg) and vitamins (4239.5 mg/kg). The nitrate content in fruits of strawberry and banana averaged at 24.0 mg/kg and 438.5 mg/kg, respectively. Nitrate was not detected in other fruits. In fruiting vegetables nitrate contents were less than 1000 mg/kg. In onion, lotus root and radish, nitrate contents were 253.7mg/kg, 352.4mg/kg and 2849.0 mg/kg, respectively, with no detection in garlic. Nitrate contents in mushrooms were less than 100 mg/kg.

• Analytical Science and Technology
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• v.19 no.5
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• pp.415-421
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• 2006

The following concentrations of some PAHs were investigated; [benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, benzo(g,h,i)perylene, indeno (1,2,3-c,d)pyrene] in vegetables(n=160) and fruits(n=50). The food samples were purchased at the local markets in Seoul, Chuncheon, Daejeon, Kwangju and Pusan. The samples were radish, onion, bean sprouts, welsh onion, chinese cabbage, spinach, young pumpkin, garlic, cucumber, carrot, lettuce, sesame leaf, tangerine, persimmon, apple, pear and banana. The methodology involved ultrasonic extraction with dichloromethane, clean-up on Sep-Pak florisil cartridges and determination by HPLC/FLD (High Performance Liquid Chromatography/Fluorescence Detector). Overall method recoveries for 8 PAHs spiked into these products ranged from 95 to 102%. The mean level of the following PAHs were determined; benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, benzo(g,h,i)perylene and indeno(1,2,3-c,d)pyrene in vegetables and fruits was N.D., 0.014 ng/g, 0.031 ng/g, 0.016 ng/g, 0.019 ng/g, 0.091 ng/g, 0.016 ng/g and N.D., respectively.