• Korean journal of applied entomology
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• v.39 no.3
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• pp.193-197
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• 2000

Wolbachia, vertically transmitted bacterial endosymbionts, is known to induce cytoplasmic incompatibility (CI), parthenogenesis, or feminization in some insect species. The Wolbachia found to exist symbiotically as a non-virulent form in Drosophila melanogaster, however popcorn is a lethal strain of Wolbachia, which causes tissue degeneration and early death of its adult host. Popcorn-infected flies showed the delayed duration of an egg and larvae, and their pupal period and life span reduced. The oviposition and egg-hatching rate of popcorn-infected flies were decreased 15% and 80%, respectiv~ly, compared to those of the normal Wolbachia-infected flies. The pupation and emergence rates of popcorn-infected flies were 67% and 65%, respectively. When popcorn-infected flies were crossed with Wolba-chia-infected flies, and vice versa, both crosses resulted in a significant reduction in egg production, egg¬hatching, pupation, and emergence rate, and their progeny revealed the popcorn syndrome. When popcorn-infected male flies were crossed with uninfected females, popcorn was not detected in their progeny. Popcorn also maternally transmitted in flies, but it did not induce CI and affected on its host life cycle as a virulence.

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.1
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• pp.36-40
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• 2016

Mulberry fruits also have tremendous potential for providing various valuable industrial products of very high economic value for human beings. Nevertheless, through global warming, the popcorn disease caused by sclerotia forming fungi reduces the productivity of mulberry fruits in worldwide. So, in this study, we investigated damage ratio of mulberry popcorn disease in mulberry fruit production farm (Buan, Jeongueb, Sangju, Gochang in Korea). In Jeonbuk Buan, popcorn disease rate was the highest about 30%, on the other hand, in case of Gyungbuk Sangju and Jeonbuk Gochang, not damage. Also, we investigated about popcorn disease prevention by various of chemical treatment methods.

• Research in Plant Disease
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• v.25 no.4
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• pp.173-178
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• 2019

From our field investigation from 2017 to 2018, five diseases and four insect pests have been identified as the primary biotic stressors of fruit-producing mulberry, which include popcorn disease and mulberry sucker, respectively. In this study, we examined the relative control effects of selected agro-chemicals against the popcorn disease and mulberry sucker. Our systemic treatment methods to simultaneously control the popcorn disease and the mulberry sucker indicated that an integrated control method showed a superior result with the control efficacy of 89.3%, while a conventional control method resulted in 66.7%. As a result, we concluded that it is much efficient to control both disease and insect pest in mid-April while sequentially applying chemicals only for the popcorn disease from February. By considering the ecological aspects of the popcorn disease and mulberry sucker, this systemic treatment will be able to reduce the labor of growers required for the control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.489-494
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• 1998

For the purpose of improving the qualities of popcorn, potato, frozen hotdog and steamed egg, the effects of food height(0mm: HO, 5mm: H5, 10mm, 15mm: H15) for microwave cooking on physicochemical properties were investigated. In popcorn, weight loss was decreased as height increased while volume of popcorn was increased, which indicated that popcorn was poped very well as height increased. H10 showed the highest taste score in sensory evaluation. In potato, degree of gelatinization was increased as hight increased. H10 showed the highest overall acceptance score. In frozen hotdog, hardness of hotdog was decreased as hight increased and H15 showed the lowest hardness score (408.8g). In steamed egg, H5 showed the highest temperature and H10 showed the highest overall acceptance score. Physicochemical properties of food were changed by heating height of microwave heating.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.91-91
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• 2022

Popcorn grains are consumed around 10,000 tons per year, in South Korea. It is consumed in amusement parks, movie theaters and snacks. The size of the popcorn processed market in Korea is estimated to be 3.6 billon won per year. So, the popcorn grain market has good prospects. On the other hand, domestic grain is at the level of 1 %, which is less domestic production than the size of the market. Maize Research Institute has developed domestic varieties in order to increase the use of domestically produced grains. The Oyrunpopcorn variety which was commonly distributed is a preferred cultivar because it has a good popping rate compared to imported grains. In addition, 'G-Popcom', 'Oyrun #2' and 'Kichan Popcorn' were developed, which diversified the choice of the farmers. Yield per unit area is important to improve farmers' income. At present, domestic grain production is traded at 5,000 won/kg, so if the yield improves, a high farmer^ income is expected. Therefore, this study compared the growth characteristics and yield according to the appropriate sowing time and plant density to improve the yield of domestically grown popcorn. We used 'Oryunpopcorn', for this research. Agronomic characteristics were compared by sowing times April 23, May 22 and June 22. The 100 seeds weight were 15.9g, 17.7g and 15.0g, respectively. Kernel weight planted in May 22 is the highest value. Yield per 10a were 414kg, 434kg and 296kg, respectively. It shows the yield planted in May 22 was higher than other trials. Therefore, the sowing time to increase the kernel weight and yield is appropriate for planting in mid-May. The number of plants in planting density trial was 5,700 plants, 4,700 plants and 4,000 plants in 10a area. Plant height at each trial were 221 cm, 214cm and 218cm, respectively. It was the highest height in 5,700 plants trials. The 100 kernel weight were 14.8g, 15.9g and 16.5g, respectively. Low planting density trial indicated high kernel weight. Yield per 10a was 415kg, 357kg and 314kg, respectively. It was higher at high density trial than other experimental plots. Therefore, appropriate sowing time was in mid-May and planting density was 5,700 plants/10a in order to increase the yield of popcorn in South Korea. This study will be useful for farmer's income to use the domestic cultivars.

• Korean Journal of Medicinal Crop Science
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• v.28 no.6
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• pp.435-444
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• 2020

Background: As the Positive List System (PLS) is implemented in broad application to agricultural products, attention to the correct use of pesticides is also needed in the production of mulberry leaves and fruit. In this regard, three types of pesticides against mulberry popcorn disease were applied 2 - 3 times both in the field and greenhouses to prepare safety standards. Residual pesticide analysis was conducted on mulberry fruits and leaves. Methods and results: Three pesticieds, thiophanate-methyl, thiophanate-methyl·triflumizole and fluopyram registered as PLS pesticides for mulberry popcorn disease, were sprayed in the Wanju and in Buan regions, after which residual pesticide analysis was conducted using high-performance liquid chromatography (HPLC). As three pesticieds were either undetected or below the permissible level in mulberry fruit, demonstrating that they were suitable for safe spraying. However, 5.6 mg/kg of thiophanate-methyl was detected in the greenhouse after three application, which was slightly above maximum residue limit (MRL). Furthermore the level of thiophanate-methyl·triflumizole was higher than 0.2 mg/kg ("Gwasang No. 2" variety, spraying twice) or similar to 0.09 mg/kg ("Daesim" variety, spraying thrice) the permissible level (0.1T mg/kg) as the thiophanate-methyl was detected in mulberry leaves in the greenhouse. Conclusions: The spraying frequency for controlling mulberry popcorn disease in greenhouses should be limited to two times or less, especially when mulberry leaves are treated with thiophanate-methyl·triflumizole careful consideration is required if the leaves are to be used as food materials.

• Nutrition Research and Practice
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• v.6 no.5
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• pp.381-388
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• 2012

The objective of this study was to determine protein quality and hematological properties of infant diets formulated from local food materials. The food materials were obtained locally, fermented, and milled into flour. The flours were mixed as 70% popcorn and 30% African locust bean (FPA), 70% popcorn and 30% bambara groundnut (FPB), and 70% popcorn, 20% bambara groundnut, and 10% African locust bean (FPAB). Proximate analysis, protein quality, hematological properties, and anthropometric measurements of the animals fed with the formulations were investigated. The protein contents of the formulated diets were significantly higher than that of Cerelac (a commercial preparation) ($15.75{\pm}0.01g$/100 g) and ogi (traditional complementary food) ($6.52{\pm}0.31g$/100 g). The energy value of FPAB ($464.94{\pm}1.22\;kcal$) was higher than those of FPA ($441.41{\pm}3.05\;kcal$) and FPB ($441.48{\pm}3.05\;kcal$). The biological value (BV) of FPAB (60.20%) was the highest followed by FPB (44.24%) and FPA (41.15%); however, BV of the diets was higher than that of ogi (10.03%) but lower than that of Cerelac (70.43%). Net protein utilization (NPU) of the formulations was 41.16-60.20%, whereas true protein digestibility was 41.05-60.05%. Metabolizable energy (232.98 kcal) and digestible energy (83.69 kcal) of FPAB were the highest, whereas that of FPA had the lowest values. The protein digestibility values corrected for amino acid score of the diets (0.22-0.44) were lower than that of Cerelac (0.52), but higher than that of ogi (0.21). The growth patterns and hematological properties (packed cell volume, red blood cells, hemoglobin, mean corpuscular hemoglobin concentration, mean corpuscular hemoglobin, and mean corpuscular volume) of the formulated diets were higher than those of ogi, but lower than those of Cerelac. In conclusion, we established that the FPAB food sample was rated best in terms of protein quality over the other formulated diets. Therefore, a FPAB blend may be used as a substitute for ogi.

• Journal of Food Hygiene and Safety
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• v.34 no.5
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• pp.438-446
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• 2019

In this study, the nutrients of a total of 4 species of popcorn, Oryun Popcorn, Oryun Popcorn 2, G-Popcorn and Gichan Popcorn, cultivated in Gangwon-do, were analyzed and compared. The contents of these products, including their general ingredients, inorganic substances, fatty acids, reducing sugar and starch, were analyzed. The moisture, crude ash and crude fat content of the dried popcorn species were 11.54-12.54%, 0.97-1.45% and 2.48-2.62%, respectively. The crude protein content was 9.68-11.75%. As for inorganic substances, the potassium and phosphorus content were the highest. Potassium was 228.25-310.46 mg/100g and was the highest in Oryun Popcorn, and the content of phosphorus was 276.04-310.00 mg/100g. As for fatty acids, 11 types were detected. The content of linoleic acid accounted for 52.89-55.76% of the total fatty acid content showing the highest amount followed by oleic acid (24.31-26.65%) and palmitic acid (14.20-15.92%). As for amino acids, total 16 types of amino acids were detected by specie, with glutamic acid making up 17.70-18.52% of total amino acids, the highest, followed by leucine (12.30-12.54%) and proline (10.34-10.92%) in that order. The creducing sugar content by specie was 4.68-5.13% and starch content was 42.14-46.14%.

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.2
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• pp.41-49
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• 2016

We bred a mulberry cultivar named Shimgang, through local adaptability test, which is under registration as a new cultivar for fruit production. Local adaptability test had been carried out at four local places(Suwon, Chuncheon, Buan and Jinju) for five years from 2011. This variety 'Shimgang' belongs to Morus Microphylla Buckl. selected from seedlings imported from USA. Shimgang was resistant to popcorn disease and high yielding variety in fruit productivity by 111% compared to control cultivar 'Shimheung(Morus alba L.)' for three years. Although fruits of 'Shimgang' was smaller in size and lower in sugar content of mulberry fruits, it showed stronger resistance than that of 'Shimheung'. It is adaptable to every where except the places where cold and late frost damage happen frequently.

• Research in Plant Disease
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• v.19 no.4
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• pp.308-312
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• 2013

The popcorn disease caused by sclerotia forming fungi reduces the productivity of mulberry fruits in world wide. In Korea, only two species (Ciboria shiraiana and Scleromitrula shiraiana) have been reported as the major causal organisms and their morphological features are also largely unknown. Hereby, we report the first identification of another species (i.e. Ciboria carunculoides) in Korea and detailed features of their anamorphic stage. Fungi dominantly associated with sclerotia were purely isolated from infected mulberry fruits under the microscope. PCR-amplified DNA encoding 5.8S rRNA displayed 100% similarity to Ciboria carunculoides. The anamorphic features exhibited the absence of true mycelia. Instead, very short, aseptated, branched conidiophores were directly emerged from sclerotia. Phialides were usually three in number from each conidiophore, ampuliform to navicular in shape, slightly curved and tapering towards the apex. Conidia were produced from phialides and mostly found as one celled, pear shaped, not hyaline with smooth to uneven surface walled. Diversely modified features in phialides formed pseudo-mycelial structures around the host tissue. Combined all, current study is the first report of C. carunculoides isolated in Korea and the foremost detailed description of its anamorph stage.