• Korean Journal of Plant Resources
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• v.18 no.1
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• pp.161-168
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• 2005

Tuber yield and content of general component and diosgenin which is a main bioactive property were investigated in order to determine the growth characteristics of round typed yam(Dioscorea opposita L.) and the potential of artificial culture at Suwon, Korea. Tubers of round yam were initiated to form at 60 days after planting and then enlargement of tubers lasted by 160 days after planting. Compared to short typed yam(108g), tuber weight of round yam was higher(127g) on the basis of dry weight at 200 days after planting. In comparison of general component between round yam and short yam, protein of round yam$(3.62\%)$ was higher than short yam$(2.10\%)$. Water content in round yam$(64.5\%)$ was lower in short yam$(79.4\%)$, indicating a higher dry weight ratio of round yam. Hardness of round yam was 2787.6 while short yam showed about two times higher hardness(4946.9). Lightness was higher in round yam(77.4). In tuber extracts analysis, diosgenin content was respectively $3.32\%$ in round yam and $2.61\%$ in short yam.

• Journal of Practical Agriculture & Fisheries Research
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• v.6 no.1
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• pp.50-62
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• 2004

Tuber yield and content of general component and diosgenin which is a main bioactive property were investigated in order to determine the growth characteristics of round typed yam(Dioscorea opposita L.) and the potential of artificial culture at Suwon, Korea. Tubers of round yam was initiated to form at 60 days after planting and then enlargement of tubers lasted by 160 days after planting. Compared to short typed yam(108g), tuber weight of round yam was higher(127g) on the basis of dry weight at 200 days after planting. In comparison of general component between round yam and short yam, protein of round yam(3.62%) was higher than short yam(2.10%). Water content in round yam(64.5%) was lower in short yam(79.4%), indicating a higher dry weight ratio of round yam. Hardness of round yam was 2787.6 while short yam showed about two times higher hardness(4946.9). Lightness was higher in round yam(77.4). In tuber extracts analysis, diosgenin content was respectively 3.32% in round yam and 2.61% in short yam.

• Korean Journal of Weed Science
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• v.14 no.1
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• pp.49-55
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• 1994

A study was conducted to determine the effect of depth of burial, soil temperature and/or moisture on tuber sprouting of E, kuroguwai. Tubers were evenly distributed in the upper 30cm of soil. Tuber weight increased as depth of tuber formed increased. No dormancy in newly formed tubers was found, whereas mature tubers were dormant. When new tubers were subjected both to continuous $5^{\circ}C$ and to gradual decreasing temperatures regimes ranged from 20 to $1^{\circ}C$ for 30 days, the tubers remained non-dormant. Viability of tubers was reduced when buried at 5cm depth in dry and moist soil conditions, but no reduction was obtained when buried at 25cm depth, regardless of soil moisture conditions employed. Percent sprouting of tubers buried at 25cm depth increased with increasing duration of burial in three soil moisture conditions studied, wherease in dry and moist conditions percent sprouting of tubers buried at 25cm depth increased by 60-day burial and thereafter decreased. In submerged condition, tuber sprouting was greater when buried at 5cm depth than when buried at 25cm depth, and increased as duration of burial increased at the both depths.

• Journal of Bio-Environment Control
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• v.11 no.4
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• pp.193-198
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• 2002

Growth and tuber development of ‘Black Magic’calla lily as affected by the rain shelter with 50％ shading and the tuber size were investigated. Tubers of five grades in size were cultivated in the rain shelter or in the open field (control). Days to emergence of shoots in the rain shelter was accelerated by 4.2 days as compared to the open field. Emergence ratio was higher as the tuber was larger, tubers grown in the rain shelter showed the significance in the growth characteristics as compared to the control. There were no significant differences in the number of flowers per tuber between the rain shelter and the open field. Flower quality was 12.2 cm longer than that in the open field. flowering characteristics was improved with the increasing tuber size. Low infection of soft rot disease of 3∼22％ was found in the rain shelter as compared to the that of 19∼83％ in the open field. Thus tubers produced under the rain shelter showed improved quality, Even if the small tubers with diameters of 0.5∼1.0 cm were cultivated in the rain shelter, the weight and diameters of tuber harvested after approximately 7 months were 50.2 g and 5.7 cm, respectively.

• BMB Reports
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• v.29 no.2
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• pp.163-168
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• 1996

Glycosylated polyphenol oxidase was purified from potato tuber using ammonium sulfate fractionation, Sephadex G-100, and concanavalin A Sepharose column chromatography. Two or three types of polyphenol oxidase were separated on concanavalin A Sepharose. Type I and II polyphenol oxidases did not bind to concanavalin A Sepharose. Type I seemed to be an aggregated form of polyphenol oxidase. Type III polyphenol oxidase, which is presumed to be glycosylated because it was bound to concanavalin A Sepharose and eluted with $\alpha$-D-methyl glucopyranoside, was further purified by chromatography on Econo-Pac Q and Superose 12. Glycosylated polyphenol oxidase was purified 130-fold from the dissolved ammonium sulfate pellet resulting in about $6\;{\mu}g$ of the enzyme from 100 g of potato tuber periderm. The molecular weight of the glycosylated enzyme determined by SDS-polyacrylamide gel electrophoresis was about 64,000. Optimum temperature and pH of both II and type III potato polyphenol oxidases were $20^{\circ}C$ and pH 7.0, respectively. Glycosylated form of polyphenol oxidase (type III) preferred catechol to catechin as a substrate, whereas type II enzyme showed the reverse substrate preference.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.2
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• pp.125-129
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• 2001

Eight vermiculite-based root media prepared with addition of complete fertilizer (2 g/L; N-$P_2$$O_5$-$K_2$O, 10-10-14) for potatoes (Solanum tuberosum L.) and a commercial root medium were evaluated in 2000 to develop the root media suitable for potato plug seedling production. The eight media consisted of various ratios of vermiculite, perlite, peatmoss, and compost. In addition, four rates (0, 1, 2, or 4 g/L) of the complex fertilizer for potato were added to a root medium (70% vermiculite, 10% perlite, 10% peat moss, and 10% compost by volume) to determine the optimum addition rate of the complex fertilizer for plug seedlings. Compost addition to the media increased plant height, the number of leaves per plant, and top and root fresh weight of 15-day old plug seedlings. The seedlings raised in root media containing compost produced significantly higher total tuber yield. Addition of the complex fertilizer to root media enhanced seedling growth and increased the number of tubers per plant and tuber yields. The results suggest that root media containing 50% vermiculite, 0 to 20% peat moss, 10% perlite, 20 to 40% compost, and 2 g/L complex fertilizer for potato appear suitable for potato plug seedling production.

• Korean Journal of Plant Resources
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• v.12 no.2
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• pp.120-124
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• 1999

This experiment was carried out to get basic information on growth characteristics in the cultivation of Saururus Chinensis Baill. The results obtained were summarized as the follows. Growth of shoot was highest at 165 days after planting, percentage of dry matter and leaf area index(LAI) were highest 29% and 4.04 at 165 days after planting. Growth of root tuber was increased until 165 days after planting, after diminished. Dry matter weight of root tuber was highest of 961g/m$^2$ at 180 days after planting and percentage of dry matter was highest of 26% at 150 days after planting, after was stabilized. CGR, RGR, and NAR were higher at 150 days afterplanting. After 165 days after planting, increment of CGR and RGR diminished and NAR decreased.

• Journal of Practical Agriculture & Fisheries Research
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• v.5 no.1
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• pp.20-27
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• 2003

This experiment was carried out to develop an acclimatization system of tissue cultured seedling in Zantedeschia spp. There was not different in percentage of leaf emergence by the media compost of acclimatization but tuber was enlarged in sand(50%)+peatmoss(50%) treatment after 6 months growth. The optimum time for the acclimatizantion of Zantedeschia spp. was from the 20th of March to 20th of April. During this time, rate of acclimatization reached over 90 percentage. However on the 20th of august, acclimatization was low to 64-70.4 percentage. Size of tuber was enlarged in planting on the 20th of March. The weight of tuber was better in 10×10cm density of planting than others.

• Korean Journal of Plant Resources
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• v.10 no.1
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• pp.58-63
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• 1997

The experiment was done to clarify the effect of keeping material and storage temperature on weight and quality of Chinese yam (Dioscorea opposita) tuber. After the yam tubers were placed into the plastic boxes filled with different keeping materials [polyethylene (PE) film, hull, soil, sand, vermiculite], they were stored under different storage temperature(room, cold) from Oct. 15 to Mar. 15 when all the characters related to the tubers were measured. Soil or PE film as keeping materials was the lowest sound tuber rate when stored at room or cold temperature, respectively, while vermiculite was the highest in both storage temperature. When PE film and vermiculite in both storage temperatures were used as keeping materials, tuber weight were less reduced than the others. Brightness of chromaticity and moisture content were lower in room temperature storage than in cold temperature storage although the characteristics related to marketability were not affected by storage temperature. PE film had greater brightness and value 'a' of chromaticity but lower its 'b' value in the latter temperature than in the former temperature. Vermiculite, however, did the reverse result in comparison with PE film.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.2
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• pp.74-87
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• 2016

Potato phenology, growth, and yield are projected to be highly affected by global warming in the future. The objective of this study was to examine the responses of potato growth and yield to environmental elements like temperature, solar radiation, and daylength. Planting date experiments under open field condition were conducted using three cultivars differing in maturity group (Irish Cobbler and Superior as early; Atlantic as mid-late maturing) at eight different planting dates. In addition, elevated temperature experiment was conducted in four plastic houses controlled to target temperatures of ambient temperature (AT), $AT+1.5^{\circ}C$, $AT+3^{\circ}C$, and $AT+5^{\circ}C$ using cv. Superior. Tuber initiation onset was found to be hastened curve-linearly with increasing temperature, showing optimum temperature around $22-24^{\circ}C$, while delayed by longer photoperiod and lower solar radiation in Superior and Atlantic. In the planting date experiments where the average temperature is near optimal and solar radiation, rainfall, pest, and disease are not limiting factor for tuber yield, the most important determinant was growth duration, which is limited by the beginning of rainy season in summer and frost in the late fall. Yield tended to increase along with delayed tuber initiation. Within the optimum temperature range ($17^{\circ}-22^{\circ}C$), larger diurnal range of temperature increased the tuber yield. In an elevated temperature treatment of $AT+5.0^{\circ}C$, plants failed to form tubers as affected by high temperature, low irradiance, and long daylength. Tuber number at early growth stage was reduced by higher temperature, resulting in the decrease of assimilates allocated to tuber and the reduction of average tuber weight. Stem growth was enhanced by elevated temperature at the expense of tuber growth. Consequently, tuber yield decreased with elevated temperature above ambient and drop to almost nil at $AT+5.0^{\circ}C$.