• Journal of Plant Biotechnology
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• v.40 no.2
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• pp.72-78
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• 2013

To establish an efficient protocol for plant regeneration of Brassica juncea L. Czern, the effects of explant types, explant ages and cytokinins on shoot regeneration were examined in this study. Shoot regeneration was markedly affected by the explant types used in the following order: cotyledon with petiole> hypocotyl> leaf with petiole> cotyledon> leaf. Five-day-old seedlings of cotyledon with petiole explants showed the maximum shoot regeneration frequency. Of the six cytokinins-6-${\gamma}$-${\gamma}$-Dimethylallylamino-purine (2-ip), 6-${\gamma}$-${\gamma}$-Dimethylallylamino-purine riboside (2-ip riboside), 6-Benzyl amino-purine (BAP), Thidiazuron (TDZ), Zeatin, Zeatin riboside-TDZ ($8{\mu}M$) was found to be the best cytokinin for shoot regeneration with the highest shoot induction frequency (80%) from cotyledon with petiole after 4 weeks. All the regenerated plantlets were developed well and they produced morphologically normal flowers.

• Current Research on Agriculture and Life Sciences
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• v.20
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• pp.99-105
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• 2002

To develop good soybean varieties for sprouts. 285 indigenous lines and 16 recommending varieties were evaluated by the sprout and agronomic characteristics. The range of whole length, hypocotyl length, root length, and yield rate of sprouts was 9.5~23.0cm, 5.9~15.1cm, 3.2~9.2cm, and 121~695%, respectively. Yield rate of sprouts was the highest, 409%, in the lines of mixed seed coat color. At the same time, it was reversely proportional to seed weight : the smaller the seed weight, the higher the yield rate as in all other reports. The number of roots was significantly fewer in the lines of the black and the green seed coat color than others. Based on whole length, rate of root length, and yield rate of sprouts, many indigenous lines were evaluated much better than recommending varieties. In the hypocotyl color of sprouts, the brightness was higher in improved variety than indigenous lines but vice versa in redness and yellowness in general.

• 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 CROP SCIENCE
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• v.37 no.1
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• pp.93-103
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• 1992

Experiments were conducted in the research field of the Wheat and Barley Research Institute with three barley cultivars, Olbori, Kangbori and Suwon 18, which showed different growth characteristics. The highest rates of daily dry matter accumulation in grains were 1.03 1.94 mg / grain / day in early and optimum sowings and 0.88 1.88 mg / grain / day in late sowings, which occurred around 20～30 days after heading in early and optimum sowings and 15～20 days after heading in late sowings. Grains reached their maximum weight by 40 days after heading in early and optimum sowings and 35 days after heading in late sowings. Total sugar content in grains followed a pattern of linear increase immediately after heading, but it started to decrease around 20 days after heading. On the other hand, starch content continued to increase until maturity. The contents of both components were high in the order of ＆apos;Olbori＆apos; ＆gt; ＆apos;Kangbori＆apos; ＆gt; ＆apos;Suwon 18＆apos;, but they did not respond in a regular pattern to different sowings. 1,000 grain weight showed highly significant positive correlation(r=0.767$^{**}$) with the duration of grain growth, but it had negative correlations with the average (r=-0.548$^{**}$) or the sum (r=-0.595$^{**}$) of post-anthesis daily mean temperature.ature.

• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.233-239
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• 2007

This study was carried out to investigate the distribution of ${\alpha}-glucosidase$ inhibitor (AGI) activity and to evaluate horticultural characteristics of pepper (Capsicum spp.). AGI activities of pepper fruits and leaves were different from 1.0 to 20.5 times and 1.0 to 5.9 times, respectively. Weight, length and width of evaluated pepper fruit were distributed from 0.5 to 56.0 g, 0.8 to 15.4 cm and 0.5 to 6.3 cm per fruit respectively. Stem colors before transplanting varied from green to violet. Length and width of leaf were distributed from 3.1 to 5.0 cm and 2.1 to 3.0 cm. Immature fruit color was almost green and mature fruit color was almost red. In horticultural characteristics of selected pepper lines with high AGI activity, the fruit position was downward position. The immature fruit color was green in all lines except one and the mature fruit color was red in all lines. Fruit weight and fruit length of selected pepper lines with high AGI activity were distributed from 5.9 to 41.1 g and 5.9 to 17.0 cm and leaf width and leaf length were distributed from 5.8 to 29.7 cm and 3.9 to 8.7 cm, respectively. The AGI activities of pepper is widely variable between leaf and fruit. According to this result, it suggested the possibility of developing a new pepper line with high AGI activity.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.399-405
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• 2020

Recently, it is difficult to produce uniform scions and rootstocks with high quality in a greenhouse due to weather extremes. The closed transplant production system is useful for producing scions and rootstocks with desirable morphological characteristics by environment control regardless of weather outside. In this study, we investigated transpiration rates and growth of cucumber and tomato scions and rootstocks grown under different light intensity conditions for precise irrigation control in a closed transplant production system. Hanging system to measure continuously the weight of plug tray consisting of seedlings and substrate with load-cell was installed in each growing bed. Using this system, we confirmed initial wilting point of cucumber and tomato seedlings, and conducted subirrigation when moisture content of substrate was not below 50%. The irrigation time of cucumber scions and rootstocks were 7 and 6 days after sowing, respectively. In tomato scions and rootstocks grown under PPF (photosynthetic photon flux) 300 μmol·m^-2·s^-1, the irrigation time were 5, 8, 11, and 13 days after sowing. Increasing light intensity increased transpiration rates and differences of transpiration rates by light intensity was higher in tomato seedlings. The growth of cucumber and tomato seedlings was promoted by increasing light intensity, especially, hypocotyl elongation and stem thickening was affected by light intensity. Cumulative transpiration rate of plug tray in cucumber and tomato seedlings was increased by increasing light intensity, and daily transpiration rate per seedling was regressed by 1st-order linear equation with high correlation coefficient. Estimation of transpiration rates by weighing continuously plug tray of vegetable seedlings can be useful to control more accurately irrigation schedule in a closed transplant production system.

• Korean Journal of Weed Science
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• v.9 no.2
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• pp.97-102
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• 1989

1. IAA showed no significant growth of root primordia and then lateral root emerged at 2 days after IAA treatment. BA treatment, however, strongly inhibited the formation of root primordia and a few lateral roots, if any, emerged about 5 days after treatment. 2. Treatment of BA and Indol-B on the water retaining ability sampled 1, 3, 5 days after chemical treatment was apparent on the soybean sprouts sampled 5 days after treatment while the difference among the treatments was negligible when sampled 1 and 3 days after treatment. 3. BA stimulated ABA content in the hypocotyl while inhibited ABA content in the root of soybean sprouts. ABA may relate with water retaining ability. 4. Soaking the soybean seeds to several seed disinfectant chemical solution had no effect on the growth and elongation of soybean sprouts. 5. It can be recommended that container of soybean sprouts should be shut tight during growing period except irrigation because the ethylene accumulation in the container may stimulate hypocotyl swelling and inhibit length of soybean sprouts.

• Korean Journal of Agricultural Science
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• v.14 no.1
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• pp.26-37
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• 1987

This studies were conducted to investigate pathgenicity and host range of Colletotrichum dematium isolated from anthracnose of pepper, and phytoxicity of its culture filtrate and the partially purified toxin. The results obtained were as follows. 1. Investigation on the host range of C. dematium has revealed that pepper as well as soybean, tomato, spinach, and beet were highly susceptible, egg plant and water melon were moderately susceptible and stone leek was slightly suceptible, but no symptoms were produced on carrot, tabacco, cucumber and melon. 2. The culture filtrates of C. dematium in Czapeck dox liquid media were toxic to leaves of pepper and caused necrosis and wilting of the plant. The toxicity of culture filtrates was most active at 15 days after fungal growth in Czapeck dox liquid media and the toxin productivity in still culture was higher than that in shaking culture. 3. The partially purified toxic substance was isolated from the culture filtrates by the acetone precipitation method. When cuttings of various pepper cultivars were placed in the toxin solutions, suceptible cultivars and resistant cultivars were equally toxic and showed necrosis and wilting of the leaves. 4. Several other plants such as soybean, tomato and carrot were also affected with the toxin solution by shoot cutting bioassay and showed veinal necrosis, leaf spots and wilting of the shoots. 5. The acetone precipitation toxin affected seed germination of pepper, cucumber, sesame and egg plant and inhibited the growth of root and hypocotyl of the seedlings.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.285-293
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• 2018

This study aimed to evaluate the effect of height suppression of cucumber and tomato plug seedlings as affected by mechanical stimulus using brushing as environment-friendly method. Cucumber (Cucumis sativus L. 'Joeunbaekdadagi') and tomato (Solanum lycopersicum L. 'Mini Chal') seeds were sown in 40-cell plug trays ($54{\times}27.5{\times}5cm$) filled with growing medium on Oct. 9, 2017. The cultivation environment in a venlo-type glasshouse was maintained as cultivation temperature range of $15-25^{\circ}C$ and the relative humidity of $50{\pm}10%$. Nontreatment and diniconazole ($7.5mg{\cdot}L^{-1}$) application at 15 days after sowing were used as the control. In addition, brushing treatments in cucumber and tomato were applied interval of 2, 4 or 6 hrs for 15 and 20 days, respectively. Plant height, hypocotyl length, and internode length were inhibited for cucumber and tomato in the diniconazole treatment than in the control. The leaf size was reduced, both cucumber and tomato, while the SPAD increased under the diniconazole treatment. However, stem diameter of cucumber was the thickest in the 2 hrs brushing interval treatment. Fresh weights of shoot and root were the significantly lowest in the diniconazole treatment. Application of brushing improved seedlings quality by promoting dry weights of shoot and root, and compactness of tomato seedlings. The chlorophyll fluorescence of tomato seedlings drastically decreased with 2 hrs treatment, indicating that mechanical stress by brushing treatment. The relative growth rate of tomato seedlings was significantly lower in the diniconazole treatment, but cucumber seedlings were not significantly different in all treatments. As a results, height suppression of cucumber and tomato seedlings was best achievement in the diniconazole treatment by the chemical as growth regulator. In an environment-friendly point of view, however, it is considered that 2 hrs brushing interval treatment can be the applicability for replacing the chemical methods in plug seedling growth of cucumber and tomato.

• The Journal of Natural Sciences
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• v.4
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• pp.143-159
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• 1991

In order to investigate the micropropagation of Pelargonium, 2 cultivars of P. peltatum 'Pouletta' and P. zonale 'Pinto Red' were cultured in vitro on the MS basal medium supplemented with various concentrations of growth regulators. It attempted to study the induction of callus and the differentiation of organs from leaf disc, petiole segments, stem segments. hypocotyle segments and flower stalk segments. The results are summarized as follows; A. As for the initiation of callus, stem explant was proved to be the most suitable one among various explants of P. zonale 'Pinto Red'. The medium was supplemented with 1.0mg/1 BAP and 1.0mg/1 NAA. As NAA concentration increased, callus formation was enhanced, but higher concentration of NAA inhibited callus fromation. Leaf and hypocotyle explants showed less callus formation than stem and petiole explants. B. In P. zonale 'Pinto Red' petiole culture, the condition of cullus culture such as hormone concentration resulted in affecting shoots differentiation. The best result of shoots formation from the callus reculture were obtained from the combination of 0.5-1.0mg/1 BAP and 0.1-1.0mg/1 NAA when the callus was cultured in 1.0mg/1 BAP and 0.05mg/1 NAA. When the callus was cultured in medium without BAP, the shoot was not differentiated in subculture regardless to BAP and NAA concentration. and only callus was formed. C. Poly-phenol substance was observed in MS medium supplemented without PVP, in which callus was not formed from the leaf of P. peltatum 'Rouletta'. Polyphenol substance was not observed in MS medium supplemented with PVP, in which callus formation was increased. D. The callus formation of P. peltatum 'Rouletta' showed the stem explant being best result. The best result particularly in the stem explant among others. The optimal hormonal concentration was 0.1mg/1 NAA and 5.0mg/1 BAP. The shoot formation was observed at 0.05mg/1 NAA and 1.0mg/1 BAP, 0.1mg/1 NAA and 5.0mg/1 BAP. The shoot was malformed and the tissue recultured turned necrotic.