• Korean journal of applied entomology
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• v.36 no.2
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• pp.145-149
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• 1997

Occurrence pattern of major insect pests on 7 recommended potato cultivars in Korea was investigated from sowing to harvesting time at Kangneung and Daegwallyung experiment fields in 1996. Green peach aphid (Mym persicae Sulzer), potato aphid (Macrosiphum euphorbiae Thomas) and beet armyworm (Spodoptera enigua Hubner) were the major insect pests on potato leaves, and wireworm (Selatosomus puncticollis Mot.) was the major pest on tubers. There was a slight difference of average number of aphids per 50 leaves among cultivars; ranged from 22.7 on cv. Dejima to 46.3 on cv. Superior. Numbers of leaves damaged by beet armyworm larvae on cv. Shepody and cv. Jopung were 11.0 and 14.3, and these cultivars are thought to be resistant against the larvae infestation. However, degree of damage on cv. Dejima and cv. Namsuh was higher 10 times than cv. Shepody and cv. Jopung. In wireworm, the percentage of damaged tubers on cv. Irish Cobbler was lowest of 8.1%, and followed by cv. Superior, cv. Dejima, cv. Jopung, and cv. Atlantic. Whereas, those on cv. Namsuh and cv. Shepody were significantly high of 50.0% and 46.8%.

• Korean Journal of Medicinal Crop Science
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• v.2 no.1
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• pp.14-19
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• 1994

Elephant food(Amorphophallus konjac K.) have been utilized its tubers in workedmaterials for a health and diet food. The author supposed that it was increased the area of cultivation and demand. This experiments were conducted to select the proper covering material during winter in order to increase yield of tubers and decrease input by 2 year's continuous cultivation, also to verified ability of seed germination and to measured efficiency of photosynthesis of plant. The proper covering materials for wintering were rice straw and rice hull. These materials were covered at 5 cm thick and at field was promoted according to emergence appearing after winter. The yields were 5,790kg /10a at 4,730kg /10a, respectively. Yield increase was 120% and 80% than that of control. The seeds collected at August 22 were germinated about 84 percent, and it was not necessary to treatment of low temperature or germination-accelerated chemicals. The widest leaf area was ranged $1,218-1,438cm^2$ at October 20 and was varied. The efficiency of photosynthesis was highest at 65-95 days after leaf emergence. The line of broad leaf and high photosynthetic efficiency per unit area was greater compare with yield. Therefore, it was supposed that these characteristics will use a marker for selection for high-yielding lines.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.4
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• pp.367-372
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• 2017

This work was conducted to identify sweet potato [(Ipomoea batatas (L.) Lam.)] cultivars showing high yield and processing suitability in the Jeonbuk region of Korea. Shoot-slips (30 cm in length) of 14 cultivars were planted with a planting density of $75{\times}25cm$ on May 30, and cultivated with black film mulching. Vine elongation at 30 days after planting was significantly increased (> 90 cm) in 'Dahomi' and 'Sinhwangmi', and was excellent (> 250 cm) 120 days after planting in 'Sinhwangmi', 'Shinyulmi', 'Daeyumi', 'Jinhongmi', and 'Yeonhwangmi'. The branch number per plant showed a dramatic increase in 'Shinzami' 30 and 120 days after planting. The leaf number per plant showed the highest increase in 'Shinzami' 30 days and in 'Sinhwangmi' 120 days after planting. Total weight, mean weight, and number of marketable tubers per plant were significantly higher 150 days after planting than that 120 days after planting. Marketable tuber yield at 120 days was high, over 2.5 ton/10a in 'Daeyumi', 'Dahomi', and 'Jeonmi', and was considerably increased, from 3.2 ton/10a to 3.5 ton/10a, 150 days after planting. Total weight of marketable tubers per plant and marketable tuber yield 120 and 150 days after planting had significant positive correlations with vine length and number of nodes 30 days after planting. Starch value was significantly higher 150 days after planting than that 120 days after planting. 'Daeyumi' and 'Jeonmi' had good growth vigor, high yield, and high starch content; 'Dahomi' also exhibited beneficial traits such as good growth vigor, high yield, and bright orange-colored flesh.

• Korean journal of food and cookery science
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• v.20 no.1
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• pp.76-80
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• 2004

The potato tubers of Solanum tuberosum L. contain potato glycoalkaloids (PGA), a class of naturally occurring toxicants. The primary constituents of this class of compounds in potatoes are $\alpha$-chaconine and $\alpha$-solanine. The purpose of this study was to examine the effects of various cooking methods on the PGA contents in the common Korean potato Irish Cobbler variety and those in commercially produced potato products consumed in Korea. After cooking, most potatoes showed big decreases in their PGA contents compared to the uncooked samples, with the exception of baked potatoes, which maintained 90.86％ of their PGA contents. The PGA levels in boiled and blanched potatoes were reduced by 91.68 and 84.17％, respectively. However, the levels in samples boiled in 1％ salted water were only reduced by 52.10％. Potatoes fried and sauteed in oil had their PGA contents reduced to 49.42 and 49.51％ of their original levels. The reductions in the relative PGA contents by cooking method were in the order boiling〉blanching〉boiling with 1％ NaCl〉steaming〉sauteing〉frying〉microwaving〉baking. The highest remaining PGA content of the potato products in Korea was in potato chips, at 69.57mg/100g, but made with imported potatoes.

• Journal of Radiation Industry
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• v.7 no.1
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• pp.29-35
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• 2013

Microbiological populations and the sterility of commercial powdered products treated with gamma irradiation at 0~10 kGy were investigated before using them as ingredients for a non-cooked Saengsik product. We evaluated a total of 14 powdered products: 8 powdered cereals, 3 powdered tubers, and 3 powdered leafy vegetables. The total numbers of bacterial populations in non-irradiated powdered cereals, tubers, and leafy vegetables were 2.7~6.9, 5.6~6.0, and $5.3{\sim}6.8\;log\; CFU{\cdot}g^{-1}$, respectively. Moreover, coliform bacteria were not indicated in adlay, millet, germinated brown rice, soybean, and mulberry leaves powder within detection limit ($2.0\;log\; CFU{\cdot}g^{-1}$). The number of Bacillus cereus exceeded $3.0\;log\; CFU{\cdot}g^{-1}$ (the maximum limit for Saengsik products) in all samples, excluding perilla seeds, buckwheat, barley, oat, potato, and Jerusalem artichoke powder. However, a dose of 6 kGy of gamma irradiation reduced the microbiological populations in all samples, and all the powdered products met the microbial requirements for Saengsik products. Futhermore, it was confirmed that all microorganisms in the 9 powdered products, except fermented brown rice, sweet potatoes, and 3 leafy vegetables, were sterilized by 10 kGy of gamma irradiation.

• Korean Journal of Organic Agriculture
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• v.29 no.4
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• pp.561-574
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• 2021

This study was conducted to evaluate the control efficacy of the organic farming materials (OFMs) on tuber rot of Gastrodia elata caused by Fusarium spp. The antifungal activities in vitro as well as the suppressive effect of 15 OFMs on the spore germination and germ tube growth by inoculating spore suspension on immature tubers in vivo were investigated. 7 OFMs inhibited the mycelial growth of Fusarium spp. and 7 of them were microbial agents. In the screening using immature tubers, 3 OFMs were very effective with control efficacy value of 70%. Among them, sulfur provided suppressive effect on both mycelial growth and spore germination against tuber rot of G. elata. Finally, 3 OFMs were selected to test the protective and curative effects, and all chosen OFMs significantly suppressed disease incidence when applied in the preventive action, in comparison with the curative action. Especially, sulfur and Bacillus subtilis gave excellent protective control efficacy with control values of 93.2% and 86.9%, respectively, whereas its curative control effect was relatively low (73.3%, 60.2%). On the other hand, the preventive and curative effects of citronella + paraffin oil + ethyl alcohol were 73.3% and 67.0%, respectively. This study suggests that tuber rot of G. elata can be controlled by some OFMs in the rain shelter greenhouse under continuous cultivation condition and protective treatment is more important and efficient.

• Korean Journal of Agricultural and Forest Meteorology
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• v.26 no.2
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• pp.103-113
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• 2024

The effect of harvesting time on the growth, marketable tuber yield, and tuber quality of spring potato (Solanum tuberosum L. cv. Dami) were analyzed in the southern paddy fields in order to determine the optimal harvesting time. At 30-50 days after flowering, the total and marketable tuber yields of spring potato reached their maxima and commercial tuber rate was also high. External defects such as tuber malformation or crack did not occur until 40 days after flowering, but after that, secondary growth such as shooting appeared. Among the nutrient compositions of tubers, carbohydrate content accounted for more than 60% of tuber dry weight without significant difference among harvesting times until 50 days after flowering. The crude protein content decreased slightly as the harvesting time was delayed. However, the mineral nutrient content of tubers decreased with delaying harvesting time and was lowest at 30-40 days after flowering. Therefore, the optimal harvesting time of spring potato was judged to be 30-40 days after flowering, when marketable tuber size and quality were great as less affected by high temperature or waterlogging under natural environmental conditions.

• Natural Product Sciences
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• v.11 no.3
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• pp.123-126
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• 2005

Gastrodia elata Blume (Chunma) belongs to Orchidaceae, which is a perennial parasitic herbaceous plant and grows in the woods of the central provinces of China, Korea and Japan. Recently, the constituents of the tubers of this plant have been investigated by researchers who have revealed the presence of phenolic compounds including gastrodin as a major constituent, together with 4-hydroxybenzaldehyde, 4-hydroxybenzyl alcohol, parishin, 4,4-dihydroxybenzyl sulfoxide, vanillin, vanillyl alcohol, beta-sitosterol, organic acids and polysaccharides, etc. In this study, we used ultrasonicator and two kinds of enzymes for enhancement of extraction yield. We also used electronic nose for the aroma pattern analysis of Chunma extracts. The concentrations of glucose and functional constituents (gastrodin, vanillin, 4-hydroxybenzaldehyde and 4-hydroxybenzyl alcohol) were measured by biochemistry analyzer and HPLC, respectively. Therefore, we showed that the yield of extraction was increased and discomfortable odor was reduced.

• Korean journal of applied entomology
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• v.19 no.3 s.44
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• pp.135-140
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• 1980

Out of 12 seed samples of Sesamum indicum L. tested, Macrophomina phaseolina (Tassi.) Goid was detected in 7 samples for the first time in Korea. Detailed descriptions of the habit character and pycnidial and pycnospore morphology of this fungus were described. Pycnidia of this fungus were not formed on agar media but they were formed on Water Agar Leaf Media under fluorescent light. M. phaseolina caused heavy reduction in seed germination and seedling stand of sesame and produced charcoal rot symptom on potato tubers. It was also detected from over wintered plant debris and diseased seedlings in the field.

• Journal of Forest and Environmental Science
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• v.24 no.2
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• pp.79-88
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• 2008

Twenty-eight of 44 Indian Ceropegia species are endemic and their survival is threatened. As a step towards conservation, we implied in vitro methods for the sustainable propagule production in C. hirsuta, C. lawii, C. maccannii, C. oculata and C. sahyadrica. Effects of explant, growth regulators, sucrose and photoperiod were studied. High frequency microtuber production was achieved with the seedling-apical buds, grown on MS medium containing 4-6 mg $1^{-1}$ BAP, 3-8% (w/v) sucrose, under continuous illumination. Each microtuber, when subcultured proliferated to form a cluster of secondary microtubers. Every primary and secondary microtuber bore at least one shoot-bud and a root primordium. Each tuber (formed with any of the significantly effective treatments) weighed more than 500 mg, enough to plant directly in non-sterilized soils. Microtubers could be produced and proliferated round the year. Proliferation could be solely attributed to in vitro procedures as these plants bear solitary tubers in vivo. Microtubers could be sprouted in vitro to prepare ready to pot plantlets. As, this novel method succeeded for all five species, though they belong to different eco-physiological backgrounds, we recommend its implementation in the conservation programs for a broader range of Ceropegia species, supported by other integrated strategies.