• 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.

• Journal of Plant Biotechnology
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• v.33 no.1
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• pp.33-37
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• 2006

Bottle gourd (Lagenaria siceraria Standl.) has been used as a rootstock for the watermelon cultivation because of better growth ability at low temperature and avoidance from contamination of the soil disease. Since the genetic source for the elite rootstock is limited in nature, the genetic engineering method is inevitable to develop new lines especially to obtain the functionally important or multi-disease resistant bottle gourd. Recently, our lab has set up a successful system to transform the bottle gourd. in order to monitor the transformation process, GFP gene is used. Cotyledons of the inbred line 9005, 9006 and G5 were used to induce the shoot under the selection media with MS + 30 g/L sucrose + 3.0 mg/L BAP + 100 mg/L kanamycin + 500 mg/L cefotaxime + 0.5 mg/L $AgNO_3$, pH 5.8. The shoot was developed from the cut side of the explants after 3 weeks on the selection media. The shoot was incubated in the rooting media with 1/2 MS + 30 g/L sucrose + 0.1 mg/L IAA + 50 mg/L kanamycin + 500 mg/L cefotaxime, pH 5.8 and moved to pot for acclimation. Although the shoot development rate was depended on the genotype, the G5 was the best line to be transformed. Monitoring GFP expression from the young shoot under microscope could make the selection much easier to distinguish the transformed shoot from the non-transformed shoots.

• Journal of Practical Agriculture & Fisheries Research
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• v.20 no.2
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• pp.89-97
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• 2018

This study was conducted to elucidate the effect of after-ripening of gourd fruits before seed collection. Five varieties of commercial gourd varieties were cultivated and the fruits were picked after 24, 31, 50, and 70 days from pollination. For after-ripening treatments the fruits were placed for five days in a cool, air-circulated place while a number of fruits were placed for longer periods to 85 days including growing period, 24 + 62 days, 31 + 55 days, 50 + 35 days, and 70 + 15 days. The seeds collected from fruits harvested on 24^th day were not emerged at all, but the seeds from after-ripening treatment for 62 days showed 78% emergence or higher. The growth of seedlings showed the effects of after-ripening treatment of the fruits before seed collection; the seeds collected after ripening treatment showed better hypocotyl growth and larger embryo size than the non-treated seeds.

• Korean journal of applied entomology
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• v.20 no.4 s.49
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• pp.191-195
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• 1981

Cucurbits including pumpkin (Cucurbita pepo), gourd (Lagenariaa siceraria), cucumber (Cucumis sativus), melon(Cucumis melo) and watermelon(Cucurbita anguria) were diseased with mosaic symptoms. The causal virus was identified as watermelon mosaic virus(WMV). The WMV was transmitted by Myzus persicae Sulzer, and no seed borne virus was found. The virus caused large local lesions on the inoculated leaves of the Chenopodium amaranticolor and mosaic symptom on the upper leaves of Cucumis melo, Cucumis sativus, Lagenaria siceraria, Cucurbita anguria and Cucurbita pepo. There were no symptoms on the inoculated leaves of the Nicotiana tabacum var. Bright yellow, Nicotiana glutinosa, Vigna unguiculata. Petunia hybrida and Datura stramonium. Thermal inactivation point was $55\~65^{\circ}C$, dilution end point was $10^{-4}\;10^{-5}$ and longevity in vitro of the virus was $7\~8$ days. The virus showed positive reaction against watermelon mosaic virus antiserum in microprecipitin tests. The virus particles were flexuous rods in size of 750 nm.

• Korean journal of applied entomology
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• v.22 no.4 s.57
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• pp.307-313
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• 1983

Twenty-five species of fungi were deleted and identified from 27 kinds of the intercepted seeds from 5 countries. Eight species of fungi including Fusariun moniliforme were detected from the imported calabash seed (Lagenaria siceraria). These seeds were the most contaminated among the intercepted reeds tested. Six kinds of seeds including larch(Larix kaemferi) were disinfected with Vitathiram, Benlate-T and Captan. Rhynchosporium was detected from seeds treated with Vitathiram whereas Alternaria spp. were detected from seeds treated with Benlate T or Captan. Six genera of fungi were detected from the untreated seeds. In the case of germination, it seem that seed disinfectants do not have any damage on germination of seed.

• Journal of Life Science
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• v.12 no.6
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• pp.694-699
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• 2002

The present experiment was carried out to determine the effect of seed-coat softening by various chemicals, washing, chilling, and light treatment alone and in combination during desiccation of seeds on germination of gourd (Lagenaria siceraria Standl.) seeds. Potassium hydroxide, sodium hydroxide, acetone, acetonitrile, and acetamide were used as chemicals for the softening. Washing, prechilling, drying and light treatment of the softened seeds were done for a hour with tap water, for one or three weeks at 3$^{\circ}C$, 12 hr at 35$^{\circ}C$, and 14 hr a day at 3$0^{\circ}C$ with red light illumination or darkness, respectively. FR-yongjadaemok and FR-kunghap were used as test cultivars. Seed-coat softening with 10% acetone and acetonitrile for 1 hour enhanced and accelerated seed germination compared to the other chemicals and water imbibition. KOH treated for the softening was necessary to increase the germination rate of seeds for following chilling, but acetone did not influence their germinability regardless of chilling. Washing the softened seeds in tap water increased the germination rate in comparison with no-washing. During desiccation of the seeds sequentially treated with the softening, washing and chilling, red light treatment showed higher germination rate than dark one, suggesting that red light treatment are necessary during desiccation.

• Journal of Life Science
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• v.11 no.2
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• pp.166-172
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• 2001

Various types of the seeding of bottle gourd widely used as a rootstock of watermelon has been required to satisfy the farmers need. The study was done to determine the effect of light quality of blue, red and far-red lights treated with light emitting diodes on growth and morphology of bottle goured seeding and chlorophyll content of its cotyledons. The lights were treated in the growth chamber for 7 days to the seeding elapsed 8 days after sowing under natural condition, and 64 hole trays with commercial bedsoil. Plant height, length and diameter of hypocotyl, leaf area of cotyledon and first true leaf, its leaf length, number of true leaves, fraction and total dry weight were measured. Red light shortened and slenderized the hypocotyl, which lengthened by far-red light and thickened by blue light. Plant height was declined in order of far-red light treatment, blue and red lights mainly due to difference of hypocotyl length, Area and length of the first true leaf became smaller and shorter under far-red light than under the other lights. However, blue light increased leaf area of cotyledons. Two cultivars cv. Yongjadaemok and cv. Kunghap had different response to the light treatments in total seedling dry weight(dw); far-red and red light treatments showed the greatest and the least dw of hypocotyl, respectively, while blue and red lights did the greatest dw of the other organs. Among the ratio of each organ dw to total dw, those of hypocotyl and true leaves were different between the light treatments; the highest ratio of hypocotyl dw to total dw was observed in far-red light treatment but the lowest was in red light treatment. Those of the true leaves were the lowest in far-red light and similar response in blue or red light treatment. Chlorophyll content of cotyledons was decreased in order of red light treatment, blue and far-red lights, meaning that short period light treatment may influence photosynthesis of seeding and afterward its growth.

• Journal of Biosystems Engineering
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• v.26 no.4
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• pp.379-384
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• 2001

To enhance the smooth graft-taking of grafted seedlings, the excessive evapotranspiration from grafted seedlings just after grafting should be avoided. A measurement system of the evapotranspiration rate of grafted seedling under artificial lighting was set up to investigate the effect of physical environment on the evapotranspiration and graft-taking characteristics of grafted seedlings quantitatively. The evapotranspiration rate of grafted seedlings affected by relative humidity and light intensity were analyzed using the measurement system. The hypocotyl of watermelons (Citrullus vulgaris cv. Sweetdew, Hungnong Seed Co.) was slantly cut and then inserted into a hole on the stem of rootstock (Lagenaria siceraria cv. FR-King, Hungnong Seed Co.). Grafted seedlings were healed and joined for 5 days under cool-white fluorescent lamps (FL20SEX-d/18, Keumho Electric Co.) with photoperiod of 12h$.$d$\^$-1/ except dark period for one day after grafting in a closed graft-taking enhancement system developed by Kim(2000). The evapotranspiration rate and graft-taking of grafted seedling at air temperature of 23$\^{C}$ and air current speed of 0.1m$.$s$\^$-1/ was highly affected by relative humidity. But light intensity showed higher effect on the stem length of scion than relative humidity. In conclusion, it was suggested that relative humidity should be controlled at higher than 90% with photosynthetic photon flux of 50$\mu$mol$.$m$^2$$.$s$\^$-1/ to increase the survival of grafted seedlings and to produce healthy seedlings.

• Journal of Life Science
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• v.13 no.2
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• pp.137-142
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• 2003

The present experiment was done to determine the effect of priming, $GA_3$ and prechilling treatment alone and in their combination on germination of gourd (Lagenaria siceraria Standl.) seeds. Priming using $KNO_3$ and $GA_3$ were treated with different concentrations and periods whereas prechilling was done at only different periods. FR-yongjadaemok and FR-kunghap were used as test cultivars and their daily germination rates were measured at treatment levels. The best germination rate of each treatment was shown in a week prechilling at $3^{\circ}C$, a day priming with 100 mM $KNO_3$ and a day treatment with 0.01 mM $GA_3$ although the prechilling had the highest rate among them. The rate of priming treated after the prechilling was continuously decreased with its longer treatment periods and was less than no-priming. In addition, the rate of $GA_3$ treatment after the prechilling was not affected by its concentrations and treatment periods. Priming and $GA_3$ treatments before the prechilling, however, showed similar germiabilities between their treatment levels including no-treatment. The results mean that sequential order of available presowing treatments is important to enhancing the rate.

• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.351-358
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• 2016

This study investigated the effect of different relative humidity (RH) regimes on graft healing of grafted seedlings of watermelon (Citrullus vulgaris Schrad.). Two watermelon cultivars ('Speed' and 'Sambok Honey') were grafted onto the 'RS-Dongjanggun' bottle gourd rootstock (Lagenaria siceraria Stanld.) and the grafted seedlings were maintained under one of three relative humidity regimes, 95-96% [1.1-0.8 (day) or $0.8-0.6(night)\;g{\cdot}m^{-3}$ vapor pressure deficit (VPD)], 97-98% [ 0.7-0.4 (day) or $0.5-0.3(night)\;g{\cdot}m^{-3}$ (VPD)], or 99-100% [0.3-0.0 (day) or $0.2-0.0(night)\;g{\cdot}m^{-3}$ (VPD)] according to the Mollier diagram based on the air temperature of $25^{\circ}C\;day/18^{\circ}C\;night$ with 16 h photoperiod per day. Among the RH treatments, 97-98% significantly increased plant height and fresh weight of the rootstock and scion of the 'Speed' and it also enhanced the graft union connection of both cultivars after two days of grafting. However, plant height and thickness of the scion of 'Sambok Honey' was increased by the 99-100% RH treatment. Furthermore, both cultivars grown in the 95-96 and 97-98% RH treatments consisted of lower levels of endogenous $H_2O_2$ and less activities of antioxidant enzymes which illustrated the occurrence of less oxidative stress. Hence, the results of this study identified the optimal RH level for the graft healing of watermelon seedlings.