• Korean Journal of Organic Agriculture
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• v.23 no.2
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• pp.267-280
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• 2015

The study was conducted to evaluate effects of time and degree of defoliation on growth of 'Wonhwang' pear (Pyrus pyrifolia Nakai) trees managing with low pesticides as well as regrowth of cuttings in vitro. Treatments included degree of defoliation (20% and 60%) with time of defoliation (Early-Aug, End-Aug, and Early-Sep); Early-Aug (20%), Early-Aug (60%), End-Aug (20%), End-Aug (60%), Early-Sep (20%), Early-Sep (60%), and No defoliation. No defoliation and Early-Sep (20%) defoliation increased growth of water sprouts and new shoots, which were improved by delayed defoliation or 20% of defoliation. Total-C, total-N, B, and free sugar contents increased in No defoliation-shoots but decreased in End-Aug (60%)-shoots. Delayed defoliation increased total-C, total-N, and free sugar in shoots, with high contents of C, K, Ca, Mg, and B observed for 20% of defoliation-trees. Fruit yield and weight or fruit length increased in No defoliation, End-Aug (20%) defoliation, and Early-Sep (20%) defoliation, but reduced in End-Aug (60%). Fruit soluble solids content reduced in defoliation in August. Time of defoliation did not affect the fruit yield and fruit quality, while degree of defoliation influenced yield and fruit weight and length. Defoliation at End-Aug (60%) mostly increased the leakage rates of the stem cuttings at $-18^{\circ}C$ and $-21^{\circ}C$ in vitro and reduced the germination rates at $-24^{\circ}C$ and $-27^{\circ}C$. Under comparison of time and degree of defoliation, the Early-Sep defoliation increased germination rates of the stem cuttings at $-27^{\circ}C$ in vitro, and 60% of defoliation decreased the germination rates compared to the 20% of defoliation.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2001.11a
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• pp.123-128
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• 2001

건고추 재배에 있어서 여러 차례에 수확하는 관행의 방법을 단 한 차례에 수확(일시수확)하려면, 적과의 착과수를 증가시키고 착과시기를 집중할 수 있는 방법이 모색되어야 할 것이다. 그러기 위해서 고추가 유한화서이면서 일시에 적과로 성숙되는 특성을 가진 품종이 우선 개발되어야 하지만, 재배방법이나 약제처리에 의한 착과 및 착색을 조절하는 방법도 시도되어야 한다. (중략)

• Proceedings of the KAIS Fall Conference
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• 2003.06a
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• pp.337-339
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• 2003

본 연구에서는 여러 종류의 담체 중에서 Davison 952 실리카를 선택하여 실리카 표면의 하이드록시기의 양을 진공 열처리 방법을 사용하여 조절하였다. 표면 처리된 실리카를 사용하여 담지촉매를 제조한 후 폴리에틸렌(PE) 중합을 수행, 소성온도에 따른 실리카 표면의 하이드록시기 양의 변화와 담지되는 조촉매(MAO) 및 메탈로센 촉매의 양과의 상관관계를 조사하였고 실리카 표면처리와 중합 활성도 간의 상관관계를 고찰하였다. 폴리에틸렌(PE) 중합 결과 메탈로센 촉매가 가장 많이 담지된 200℃ 보다 400℃ 또는 600℃에서 메탈로센 당(g PE/mol Zr)활성도가 높았으며, 담체에 흡착된 MAO와 메탈로센의 비율이 400℃와 600℃에서 가장 크게 나타났다.

• Journal of Mushroom
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• v.9 no.2
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• pp.69-73
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• 2011

We have researched on methods which can reduce fruit-body malformations of king oyster mushroom(Pleurotus eryngii). We collected many pathogens from diseased fruit-body or malformated fruit-body and identified with chemicobiological test and microscope. The factors of fruit-body malformations and increment of contamination during the pin-heading induction time were researched with ventilation amounts in growing room. When the pathogens having high pathogenicity were inoculated in spawn running bottle and at pin-heading induction time, symptom appeared or not appeared in according to air ventilation amounts in growing room. During the pin-heading induction time, humidity degree in growing room have kept of high level and air ventilation amounts were so little that fruit-body malformations ratio was high. But, even though pathogens were inoculated at the surface of bottle factitiously, if air ventilation amounts were enough, fruit-body malformation ratio was low.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.518-524
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• 2015

The objective of this research was to investigate the influence of various depths of expanded rice hull (ERH) medium and fixation dates of runner plantlets of 'Seolhyang' strawberry on the growths in nursery field and in plastic house soil after transplanting. The five treatments in medium depths (30, 50, 70, 90, and 110 mm) and four treatments in fixation dates (1st and 15th July and 1st and 15th August) were tested. The growths of runner plantlets were investigated before transplanting to plastic house soil. The early growth and inflorescence rates of crops after transplant to plastic house soil were also investigated. The plant height and fresh weight of runner plantlets were the highest in the medium depths of 50, 70, and 90 mm. The medium depth of 30 mm had higher numbers of first roots, but lower root fresh weight compared to those of 70, 90, and 110 mm. The treatment of 30 mm in medium depth showed poorer growth in all indexes except root length and root weight compared to those of 70, 90, and 110 mm. The runner plantlets fixed on July 1 and July 15 showed good root growth and the weights of ERH adhered to form root balls were 18.3 g and 13.9 g, respectively. The detached amount of ERH was less than 40% in the two treatments when root balls were shaken by a vibratory sieve shaker. The plant growth at 45 days after transplanting to plastic house soil were not significantly different when the runner plantlets were fixed in the period from July 1 to Aug. 1. The inflorescence rates of the first cluster were 93 to 100% when runner plantlets were fixed in the period from July 1 to Aug. 1. By contrast the runner plantlets fixed on the Aug. 15 had a 67% in florescence rate for the first cluster. These results indicate that optimum depth of ERH medium was 7 cm and the ranges of optimum fixation dates are from July 20 to 25.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.232-237
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• 2003

Benzyladenopuyine (BA) commonly used for soybean sprout production is of high price. The study was carried out to determine the effect of BA treatment time during seed imbibition on growth and development of soybean sprouts and to analyse its treatment cost. The soybean seeds of 4 cultivars were soaked in 4 ppm BA solution during the first 5.5 hour imbibition (EFHI), the second 5.5 hour imbibition (SFHI) immediately after 0.5 hour aeration, or whole 11.0 hour imbibition (WFHI) intervened by aeration. On the 6th day after culture, the soybean sprouts were classified into 4 categories on the base of hypocotyl length; ＞ 7cm, 4 to 7cm, ＜ 4 cm and not germinated, and their morphological characters, fresh and dry weights were measured. Water absorption of the seeds was sharply reduced after it was almost done for the first 5.5 hours. The percentage of sprouts with hypocotyls of longer than 4cm was higher in FFHI treatment than in the other two ones. Regardless of BA imbibition time and periods, the lateral roots were not observed. WFHI treatment showed shorter hypocotyl and root lengths but thicker hypocotyl and hook diameters than FFHI and SFHI treatments. All component fresh and dry weights except cotyledon fresh weight were nearly same. Treatment cost of BA was the lowest in SFHI treatment. It is concluded that BA treatment during SFHI is the best time because its treatment time did not affect sprout growth but its treatment cost.

• Journal of Bio-Environment Control
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• v.12 no.4
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• pp.173-179
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• 2003

This study was established to control the overgrowth of cucumber and tomato plug seedlings by controlling of irradiation timings light intensities of red (R) light. Compared with the control, end-of-day (EOD) timing of R irradiation significantly reduced the seeding heights by 21.3% and 14.2% in cucumber and tomato, respectively. In addition, both plant seedlings treated with R light at EOD timing had the thickest stem diameter. Tomato seedlings treated with R light at EOD showed th highest chlorophyll content and the smallest leaf size. Dry weights of above ground plant tissue in both plant seedlings were significantly reduced by EOD R light treatment. And both plant seedlings treated with EOD treatment had the lowest T/R ratio, and the highest compactness rates. The increased intensities of R light resulted in the shorter plant heights in cucumber and tomato plant seedlings. It also reduced the length of hypocotyls and internodes and the size of leaves in the both seedlings. Elevated R light intensities tended to increase the stem diameter and chlorophyll contents. Dry weights of above ground plant tissue and roots in both plant seedlings were reduced by the elevated R irradiation. Cucumber seedlings treated with 2 and 8 $mol{\cdot}m^{-2}{\cdot}s^{-1}$ and tomato seedlings treated with 8 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ had significantly lower T/R ratio the other treatments tested.

• Korean Journal of Weed Science
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• v.9 no.1
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• pp.34-38
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• 1989

This study was conducted to investigate the tuberization time and the control method for Eleocharis kuroguwai Ohwi. The control methods were compared the shoot cutting and bentazon treatment for E. kuroguwai with untreatment. The initial tuberization time of E. kuroguwai, when E. kuroguwai was planted and without rice planted, was about August 18th and 10th, respectively. When the shoot of E. kuroguwai was cut, the regrowth vigour scarcely revived for the cutting on September 12. The least tuberization of E. kuroguwai, when E. kuroguwai was just planted and planted with rice plant, were on August 28 and August 3 to the top cutting of E. kuroguwai, respectively. Bentazon treatments from July 19 to August 3 hardly induced tuberization of E. kuroguwai, while as the delay of bentazon treatment time the tuberization of E. kurguwai was little by little increased.

• The Korean Journal of Pharmacology
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• v.25 no.1
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• pp.93-99
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• 1989

In our previous studies, it was found that activities of maternal peripheral lymphocytes and thymocytes were depressed during the implantation period in rats and rabbits. This study was therefore attempted to clarify further this immunosuppression locally by determining lymphocyte response in lymph nodes draining the uterus (DLN) and to elucidate the mechanism by which prostaglandin E (PGE) modulates immune response during the implantation process in rats. As compared with non-pregnant rats, the response of DLN lymphocytes to concanavalin A (Con A) was depressed during the implantation period in 100% of rats studied. The activity of DLN lymphocytes depressed on day 8 of pregnancy was, however, restored partially by the treatment of indomethacin (ID), indicating that prostaglandin (PG) might be one of factors responsible for immunomodulation during the process of implantation. DLN lymphocyte activity in non-pregnant rats was suppressed if PGE was pre-treated prior to Con A and this suppression was partially restored by the treatment of ID. Furthermore, DLN lymphocytes pre-treated with PGE produced PGE in vitro and this PGE production was blocked by the treatment of ID, suggesting that PGE induced PGE-producing cells. However, the pretreatment of estradiol, progesterone, and hCG at doses enough to suppress lymphocyte activity was ineffective in inducing PGE-producing cells. From these results, it is suggested that PGE induces PGE-producing suppressor cells, thereby increasing PGE concentration and PGE in turn depresses maternal local immune response as well as systemic immune response during the implantation period in rats.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.1
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• pp.71-80
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• 2004

This study was conducted to investigate the effects of the type and application season of animal manure (AM) on herbage productivity, efficiency of nitrogen utilization in mixed grassland. Main plots were the types of AM, such as cattle feedrot manure (CFM), swine manure fermented with sawdust (SMFWS) and cattle slurry (CS). Subplots were the seasons of AM application. such as application in autumn or in spring as single dressing. and application in autumn and spring as a 50:50 split dressing. The results obtained where summarized as follows ; 1. Herbage productivity and nutritive value were hardly influenced by type and application season of AM. 2. Nitrogen efficiency of CFM and CS was lower than that of SMFWS. 3. Organic matter (OM) content in the soil was not significantly different by the type and application season of AM. OM content among AM treatments was the highest with CFM and the lowest with CS. 4. Nitrogen content of the soil was hardly influenced by the type and application season of AM and not affected by the interaction between the type and application season of AM.