• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.933-938
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• 2005

To investigate pertinent packaging treatment of fresh-cut potatoes (Solanum tuberosum L.), potato cubes were subjected to passive, gas exchange, and vacuum packaging conditions. Low density polyethylene film (LDPE), polypropylene film (PP), anti-fogging film (AP), and perforated film (PF) were used as passive packaging treatments. Mixed gases of 5% $CO_2/5%\;O_2$ (MA1) and 10% $CO_2/5%\;O_2$ (MA2) were applied as gas exchange packaging. Packs filled with cubes were kept at $5^{\circ}C$, and changes in weight loss, surface color, vitamin C content and sensory quality of cubes were analyzed during storage. Respiration rate of cubes was 2.11 times higher than that of intact raw potatoes at $5^{\circ}C$. Gas concentrations in passive packaging was maintained at 1-2% $O_2$ and 4-14% $CO_2$ after 7 days. Gas levels changed depending on films used. Cubes packed in PP and MA2 showed lowest weight loss and browning during storage. Firmness of cubes was not affected by packaging treatment. Vitamin C content was highest in cubes packed with AF. Cubes packed in MA2 showed highest quality upto 10days storage, followed by those packed in PP and AF.

• Korean journal of applied entomology
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• v.43 no.2
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• pp.129-134
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• 2004

A simple and easy method was developed to monitor fungus gnats, Bradysia agrestis on sweet pepper in greenhouses. The larvae of B. agrestis were more attracted to potato discs than other sweetpotato, carrot, garlic, radish, and onion discs. The average numbers of B. agrestis found in each disc were 9.7 (potato), 6.0 (sweetpotato), 4.3 (carrot), 0.7 (garlic), 3.8 (radish), and 1.0 (onion). The number of larvae also increased by the size of disc surface and resulted in 2.1 larvae in 10${\times}$10${\times}$10 mm, 3.4 larvae in 20${\times}$20${\times}$10mm, and 3.9 larvae in 30${\times}$30${\times}$10 mm. The adults were more attracted to a yellow sticky trap (50.0 numbers) than a blue (18.0 numbers) or a white (3.7 numbers) traps. The optimal height for installing sticky trap in the greenhouse was determined as less than 50 cm from the rockwool bed based on the adults caught in the traps; 50.0 in less than 50 cm, 4.3 in 50-100 cm, and 2.0 in more than 100 cm height.

• Korean Journal of Plant Tissue Culture
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• v.27 no.1
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• pp.39-45
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• 2000

Two maize transposable elements, immobilized Ac (iAc) and Ds, have been introduced into the genome of a diploid potato clone (Solanum tuberosum Group Phureja clone 1.22). The iAc is a modified Ac that is supposed to be unable to transpose but is expected to trans-activate the transposition of a Ds that is unable to transpose by itself. When the leaf and stem explants of in vitro shoots of the clone 1.22 were inoculated with Agrobacterium tumefaciens strains harboring binary vectors containing the iAc and the Ds, calli were formed from the explants on media containing 50 mg/L of kanamycin, and shoots were regenerated from the calli. The regenerated shoots formed roots when cultured on media containing 100 mg/L of kanamycin, whereas untransformed shoots did not form roots on the same media. The PCR amplification of the DNA's from the transgenic plants confirmed that the iAc and the Ds elements were introduced into the potato genome of 1.22.

• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.358-365
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• 2006

To study simultaneous water and solute transport kinetics during soaking in concentrated solution, the influence of the concentration and molecular weight of the solute(polyethylene glycol(PEG) and NaCl) in the soaking solution and the temperature on the water loss and solute gain rates were observed by using a model vegetable tissue(potato). When potato slices$(4cm{\times}4cm{\times}0.1cm)$ soaked in 60% PEG solutions, the water loss rate of the early phase decreased with increasing of the molecular weight of PEG from 200 to 6,000, while the final water loss increased with increasing the molecular weight of PEG and it reached to 80%. The cell wall of potato tissue was permeable to NaCl and PEGs of which average molecular weight is smaller than 400 but it was not permeable to PEG 600 and larger molecules. PEG which has average molecular weight below 600 induced plasmolysis and those above 600 induced cytorrhysis. The water loss rate of potato sample soaked in smaller molecular weight PEG solution was faster than those soaked in higher molecular weight PEG solution before cytorrhysis happened. The water loss rate was reversed after cytorrhysis happened. The volume change of potato within the first 60 minutes was larger in low molecular PEG solution but the final ratio of decreasing volume was larger in high molecular PEG solutions. In PEG 200 solution, the potato tissue was slightly shrinked without shape change. However, in PEG 4,000 solution, volume of potato was reduced significantly and potato tissue was twisted.

• Korean Journal Plant Pathology
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• v.13 no.4
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• pp.205-209
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• 1997

Potato spindle tuber viroid(PSTVd) RNAs were isolated from PSTVd-inoculated potato cv. Superioc and carried out RT-RCR with reverse transcriptase and PSTVd specifie primer pair desigened to amplify the 356 nucleotides of PSTVd genome. As a result, 356 nucleotides PCR products were amplified from PSTVd-inoculated potato cv. Superior. The 356 nucleotides DNA fragment was indeed the PSTVd geneby sequencing analysis. PSTVd could be successfully detected from infected leaf and tuber tissue of potato by using RT-PCR technique. Especially PSTVd was more effectively detected when both downstream and upstream primer were used than only downstream primer was used in RT reaction.

• Food Science and Preservation
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• v.12 no.6
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• pp.552-557
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• 2005

Effect of pre- and post-mild heat treatment on quality of fresh-cut potatoes was investigated with the focus on surface color, firmness, phenolics, vitamin C and sensory characteristics. As the pre-heat treatment before cutting of potatoes, dried hot air (DH) and hot water (WH) treatment were conducted at $45^{\circ}C$ for 60 min, respectively. As a post-heat (CH) treatments, potato cubes were dipped into water of $55^{\circ}C$ for 45 seconds after cutting. The potato cubes were packed in 15 cm x 20 cm LDPE pouches $30^{\mu}m$ thick and then stored at $5{\pm}1^{\circ}C$. The respiration rate of fresh-cut potatoes was decreased by mild heat treatment Especially, the rate of cubes treated with DH was decreased by $20\%$ compared to that of the non-heat treated. L value of cubes treated with DH showed higher value than that of others. Firmness and free phenolics had no significant difference between the treatments. The fresh-cut potatoes prepared with non-heat treatment showed higher vitamin C content than that of the heat treated. In sensory visual color, CH treated cubes marked the best quality. Conclusively, mild heat treatment, especially CH treatment, showed positive effect on browning inhibition and quality enhancement of fresh-cut potatoes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.6
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• pp.432-436
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• 2002

This study was conducted in 2001 to determine the influence of seed-piece size (SPS) and number (SPN) per mini-tuber produced by hydroponics on growth and yield of potato (Solanum tuberosum L.). Treatments consisted of the combination of six SPS (3, 5, 7, 9, 11, 13g/seed-piece) and four SPN (whole tuber, and two, three, and four pieces/tuber). Percentage sprout emergence at transplanting was higher for seed pieces weighing 7 to 13 g (83.0 to 85.4%) and for three and four pieces per tuber (85.4 and 84.8%). As SPS were increased from 3 to 9 g/piece, total yields markedly increased from 2,052 to 2,924 kg/10a and seed tuber (31 to 250 g) yield from 1,589 to 2,428kg/10a with no further increase with SPS. As SPN was increased from one to three/ tuber, total yields increased from 1,918 to 2,982 kg/10a and seed tuber yields from 1,422 to 2,579 kg/10a with no further increase with SPN. Average tuber weight increased with SPS (46.3 to 71.5 g/tuber) and SPN (56.5 to 64.9 g/tuber).

• Korean Journal of Agricultural Science
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• v.20 no.2
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• pp.133-144
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• 1993

Calli were induced on microtuber disks of potato(S.tuberosum) infected with three binary vectors transconjugated with C58, A281 and LBA 4404 of Agrobacterium tumefaciens and pBI121. The frequency inducing callus was the highest by infection of C121 carrying pC58 and pBI121, and shoots were differentiated on the calli without any hormonal application. Transformed calli were selected by their resistance to kanamycin and identified by GUS activity. The frequency of callus formation by infection of binary vector strain was affected according to the hormonal application.

• Korean Journal of Plant Tissue Culture
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• v.25 no.6
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• pp.477-485
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• 1998

To underatand in vitro regulation of differentiation, the effects of growth regulators and nitrogen source on metabolism of cell wall polysaccharides in suspension culture of kidney bean (Phaseolus vulgaris L.) were investigated. The suspension cells (cell clusters) were directly induced from the epicotyl segments of the seedlings, which were cultivated in MS medium supplemented with 1.0mg/L of 2,4-D and 0.5 mg/L of kinetin. When compared with cell wall sugar contents of the epicotyl segments, the cellulose content of the suspension-cultured cells decreased; while the pectin and hemicellulose content increased; suggesting increases of rhamnogalacturonan I and arabinogalactan IIduring the dedifferentiation, respectively, The effects of growth regulators(2,4-D, 1.0mg/L and kinetin, 0.5mg/L) and nitrogen source (potasium nitrate, 19.0mg/L and ammonium nitrate, 16.5 g/L) in the medium on the proliferation and the turnover of the cell wall polysaccharides were investigated for 30 days. In the medium with growth regulators and without nitrogen source, the proliferation rate was extremely high (16 folds). Growth regulators and nitrogen source increased the pectin content. Analysis of neutral sugar composition of pectin fraction showed that nitrogen source enhanced rhamnose level remarkably, suggesting that rhamnogalacturonan I was the one most likely synthesized. In hemicellulose fraction, growth regulators reduced arabinose level, suggesting that arabinogalactan II was degraded. And nitrogen source reduced galactose level, suggesting that xyloglucan was also degraded.

• Journal of Plant Biology
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• v.25 no.2
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• pp.65-72
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• 1982

The oxygen consumption of fresh and aged slices of potato tuber was 40.6 and 168.0 ,$0_2$ $\mu$l/g fr $wt{\cdot}h$, respectively. After initial burst of oxygen consumption within 2 minutes(i.e., 40% for fresh and 12% for aged slices) in the treatmentof $50{\mu}M$ alantolactone, gradual decrease of respiration rate was observed during 3 hours of incubation. In case of the aged slices the initial burst of oxygen consumption was not observed by salicylhydroxamic acid (SHAM) or KCN. The combined effect of SHAM and alantolactone showed increase of 12%, while SHAM and KCN combination showed 60% decrease. In addition, the lipophilicity of cell membrane of onion inner epidermis was increased by lantolactone treatment. The results suggest that the primary effect of alantolactone on the cellular respiration may be associated with an alteration of lipophilic phase of cell membrane and a consequent increase of electron flow throuh the cytochrome system.