• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.71-80
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• 2005

Effects of low temperature ($8^{\circ}C$) on the hydraulic conductivity of young roots of a chilling-sensitive (cucumber; Cucumis sativus L.) and a chilling-resistant (figleaf gourd; Cucurbita ficifolia Bouche) crop have been measured at the levels of whole root systems (root hydraulic conductivity, $Lp_r$) and of individual cortical cells (cell hydraulic conductivity, Lp). In figleaf gourd, there was a reduction only in hydrostatic $Lp_r$ but not in osmotic $Lp_r$ suggesting that the activity of water channels was not much affected by low root temperature (LRT)treatment in this species. Changes in cell Lp in response to chilling and recovery were similar asroot level, although they were more intense at the root level. Roots of figleaf gourd recovered better from LRT treatment than those of cucumber. In figleaf gourd, recovery (both at the root and cell level) often resulted in Lp and $Lp_r$ values which were even bigger than the original, i.e. there was an overshoot in hydraulic conductivity. These effects were larger forosmotic (representing the cell-to-cell passage of water) than for hydrostatic $Lp_r$. After a short term (1 d) exposure to $8\;^{\circ}C$ followed by 1 d at $20\;^{\circ}C$, hydrostatic $Lp_r$ of cucumber nearly recovered and that of figleaf gourd still remained higher due to the overshoot. On the contrary, osmotic $Lp_r$ and cell Lp in both species remained high by a factor of 3 as compared to the control, possibly due to an increased activity of water channels. After pre-conditioning of roots at LRT, increased hydraulic conductivitywas completely inhibited by $HgCl_2$ at both the root and cell levels. Different from figleaf gourd, recovery from chilling was not complete in cucumber after longer exposure to LRT. It is concluded that at LRT, both changes in the activity of aquaporins and alterations of root anatomy determine the water uptake in both species. To better understand the aquaporin function in plants under various stress conditions, we examined the transgenic Arabidopsisand tobacco plants that constitutively overexpress ArabidopsisPIP1;4 or PIP2;5 under various abiotic stress conditions. No significant differences in growth rates were found between the transgenic and wild-type plants under favorable growth conditions. By contrast, overexpression of PIP1;4 or PIP2;5 had a negative effect on seed germination and seedling growth under drought stress, whereas it had a positive effect under cold stress and no effect under salt stress. Measurement of water transport by cell pressure probe revealed that these observed phenotypes under different stress conditions were closely correlated with the ability of water transport by each aquaporin in the transgenic plants. Together, our results demonstrate that PIP-type aquaporins play roles in seed germination, seedling growth, and stress response of Arabidopsis and tobacco plants under various stress conditions, and emphasize the importance of a single aquaporin-mediated water transport in these cellular processes.

• Korean Journal of Environmental Agriculture
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• v.21 no.3
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• pp.202-207
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• 2002

To establish the seed treatment method of the gamma radiation for germination enhancement of bottle gourd(Lagenaria siceraria Standl.) and pumpkin(Cucurbita ficifolia Bouche), seeds were irradiated with the dose of 1$\sim$20 Gy of the gamma radiation. The germination rate in irradiated group was higher than that of the control, depending on seed condition. In the case of bottle gourd, the germination rate of 70$\sim$80% germinative seed was increased at 4$\sim$20 Gy irradiated groups. Especially, it was the highest at 4 Gy irradiated group. The germination rate of 80$\sim$90% germinative seed was the highest at 4 Gy irradiated group. The germination rate of 70$\sim$80% and 80$\sim$90% germinative seed at 4 days after sowing was increased 66% and 26% at 4 Gy irradiated group, respectively. In the case of pumpkin, the germination rate of 70$\sim$80% and 80$\sim$90% germinative seed was increased at 2 Gy and 8 Gy irradiated group, respectively. Effect of the low-dose gamma radiation on the early growth was enhanced depending on their germination enhancement. Especially, it was the highest at 2 Gy irradiated group of 70$\sim$80% germinative seed of pumpkin. Catalase activity of bottle gourd was increased at 4 Gy irradiated group. Catalase and peroxidase activity of pumpkin were increased at 2 Gy and 8 Gy irradiated group. These results suggest that the germination, early growth and physiological activity of bottle gourd and pumpkin seeds could be promoted by the low dose gamma radiation.

• Proceedings of the Botanical Society of Korea Conference
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• 1999.04a
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• pp.10-10
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• 1999

• Nutritional Sciences
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• v.6 no.3
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• pp.148-154
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• 2003

Although various raw plant materials have been demonstrated to exert anti-obesity effects to a greater or lesser extent in both humans and animals when they are used to supplement the diet, it has not been shown extensively that they influence adipocyte cell differentiation involving lipid metabolic gene expressions. Using a well-established 3T3-L1 preadipocyte differentiation system, we decided to look into molecular and cellular event occurring during adipocyte differentiation when raw plant materials aye included in the process, in an effort to demonstrate the potential use of a screening system to define the functions of traditionally well-known materials. To these ends, the effects of ethanol (EtOH) or EtOH/distilled water (DW) extracts of Wax Gourd were examined using cytochemical and molecular analyses to determine whether components of the extracts modulate adipocyte differentiation of 3T3-Ll preadipocytes in vitro. The cytochemical results demonstrated that EtOH or EtOH/DW extracts did not affect lipid accumulation and cell proliferation, although the degree of lipid accumulation was influenced slightly depending on the extract. EtOH extract was highly effective in apoptotic induction during differentiation of 3T3-Ll preadipocytes (p<0.05). Reverse transcription-polymerase chain reaction (RT-PCR) analysis of lipoprotein lipase (LPL), Uncoupling protein (Ucp) 2, 3 and 4 also showed that while LPL expression was not influenced, Ucp2, 3 and 4 were up regulated in the EtOH extract-treated group and down regulated in the EtOH/DW extract-treated group. These changes in gene expressions suggest that the components in different fractions of Wax Gourd extracts may modulate lipid metabolism by either direct or indirect action. Taking these results together, it was concluded that molecular and cellular analyses of adipocyte differentiation involving lipid metabolic genes should facilitate understanding of cellular events occurring during adipocyte differentiation. Furthermore, the experimental scheme and analytical methods used in this study should provide a screening system for the functional study of raw plant materials in obesity research.

• The Korean Journal of Pesticide Science
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• v.2 no.2
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• pp.108-112
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• 1998

This studies were conducted to investigate the effects of hexaconazole on growth of watermelon(Citrullus lanatus Schrad) and ethylene evolution from gourd(Lagenaria siceraria Standl). While foliar application of hexaconazole exhibited inhibition effect, little or no inhibition was found in the plants treated with soil drench application. The plant height and number of internode in watermelon were significantly inhibited at 7 days after treatment(DAT), but no significant difference was found at 42 DAT. No significant difference was found in site of female flower setting when treated with hexaconazole. The length of branch was significantly inhibited at the 2nd or the 3rd internode. It was suggested that the inhibition of stem elongation was related with application timing of the chemical. Hexaconazole increased ethylene evolution more effectively at earlier stage of gourd, but after 5 DAT ethylene evolution was decreased.

• The Korean Journal of Food And Nutrition
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• v.22 no.1
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• pp.20-28
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• 2009

According to traditional oriental medicine, only non-coagulated native deer blood is said to be effective, and coagulated deer blood is ineffective. Thus, a drying and tablet-producing method for deer blood was developed to maintain its physiological and therapeutic activity, and so that after drying, it can be redissolved and protected from coagulation. Proteases such as trypsin, pepsin, chymotrypsin, and aminopeptidase were added to the deer blood indicating that it coagulated in an hour, as shown by the reference. Wax gourd extract, which is high in protease, was added to the blood resulting in anticoagulation for 31 hours. Also, additions of 1% EDTA, 0.38% sodium citrate, 0.16% calcium oxalate, 1.2% ethanol, and 0.006% heparin to the deer blood resulted in anticoagulation for 1 hour, 4 hours, 2 hours, 1 hour, and 31 hours, respectively. In an experiment using 0.19% sodium citrate plus 1% wax gourd extract, and 0.006% heparin plus 1% wax gourd extract, anticoagulation was maintained for up to 72 hours. However, since heparin can not be used in food, the deer blood tablet was made with the addition of 0.19% sodium citrate and 1% wax gourd extract, followed by freeze drying. The dissolution rate for the tablet manufactured in this manner was 96.7%. And the dissolution rates for spray-dried deer blood, vacuum-dried deer blood, and marketed deer blood tablets were 85%, 81%, and 25.5%, respectively. The composition of the tablet produced from the freeze-dried deer blood was 56.4% protein, 18.7% lactose, 1.2% amino acids, 1.0% glucose, 0.7% lipids, 180 mg/100 g of iron, 13 mg/100 g of potassium, 39.1 mg/100 g of calcium, 480 mg/100 g of sodium, 368 mg/100 g of chloride, each.

• Research in Plant Disease
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• v.10 no.1
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• pp.53-57
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• 2004

Cucumber green mottle mosaic virus (CGMMV) was a major pathogen of watermelon and had affected seriously to watermelon production in Korea. Rapid and sensitive detection method of CGMMV associated with bottle gourd (Lagenafia siceraria) seeds was developed by using RT-PCR in this study. A pair of primeri Wmfl and Wmrl, specific for CGMMV was designed from coat protein gene sequences of CGMMV-W and used for amplifying 420 bp product in RT-PCR. To simplify the virus extraction procedure and reduce an inhibitor from the extract for the RT-PCR, some methods using ethanol precipitation, double filtration, polyethylene glycol precipitation and phenol/chloroform/isoamyl alcohol extraction procedure were compared and the phenol/chloroform/isoamyl alcohol extraction procedure was selected by its enhanced sensitivity. This detection method using the selected extraction step and the primers for RT-PCR could reliably detect an infected level of one CGMMV-infested seed in 1,000 seeds. This rapid and sensitive RT-PCR assay provides auseful tool for the specific detection of CGMMV in bottle gourd seed samples containing high levels of back-ground inhibitors.

• Horticultural Science & Technology
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• v.17 no.6
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• pp.747-749
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• 1999

Various methods for seed treatments have been devised to improve the rate and uniformity of seed germination of gourd (Lagenaria siceraria Standl.). Hydropriming and priming, the imbibition of seeds in distilled water and osmotic solutions respectively, are useful techniques for early establishment of uniform seedlings. In this study, the optimum conditions for hydropriming and priming were determined in gourd (Lagenaria siceraria Standl.) seeds. Effect of hydropriming was compared with those of osmotic priming. Seeds, hydroprimed or primed with 50 mM solution of $KH_2PO_4$ and $KNO_3$ at $30^{\circ}C$ for 2 days, showed shorter $T_{50}$ (number of days to 50% of the final germination percentage) and MDG (mean number of days to germination) than those unprimed. The relative effectiveness of hydropriming and priming in improving the germinability of gourd seeds was more evident when germinated at $20^{\circ}C$ than at $25^{\circ}C$ and $35^{\circ}C$.

• Research in Plant Disease
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• v.18 no.1
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• pp.54-56
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• 2012

Sclerotium rot of sponge gourd occurred at the experimental field of Gyeongsangnam-do Agricultural Research and Extension Services in August 2010. The infected fruits showed water-soaked and rot symptoms. White mycelial mats spread over lesions, and then sclerotia were formed on fruit and near soil line. The sclerotia were globoid in shape, 1-3 mm in size and white to brown in color. The optimum temperature for mycelial growth and sclerotia formation on PDA was $30^{\circ}C$ and the hyphal width was 4-8 ${\mu}m$. The typical clamp connections were observed in the hyphae of the fungus grown on PDA. On the basis of mycological characteristics, ITS rDNA sequence analysis, and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report of sclerotium rot on sponge gourd caused by S. rolfsii in Korea.

• Plant Biotechnology Reports
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• v.4 no.2
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• pp.101-107
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• 2010

An efficient plant regeneration system has been developed for figleaf gourd (Cucurbita ficifolia Bouch$\'{e}$), which is exclusively used as a rootstock for cucumber. The protocol is based on results obtained from a series of culture experiments involving different parts of the cotyledons and various media. The culture of cotyledon explants was critical for the enhancement of shoot regeneration frequency. The lower parts of the cotyledon excised at the plumule base were found to display a markedly enhanced production of adventitious shoots compared to other cotyledon regions. Culture in silver nitrate-supplemented Murashige and Skoog (MS) medium was not beneficial for shoot regeneration and suppressed root regeneration. Efficient shoot regeneration was obtained on MS medium containing 1.0 $mg\;l^{-1}$ zeatin and 0.1 $mg\;l^{-1}$ indole-3-acetic acid. Regenerated shoots successfully elongated and rooted in medium containing 0.1 $mg\;l^{-1}$ 1-naphthalene-acetic acid after 10-15 days of subculturing. The plantlets were satisfactorily acclimatized in a greenhouse and grew into normal plants without any morphological alterations.