• The Korean Journal of Ecology
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• v.26 no.4
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• pp.189-197
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• 2003

Properties of seed production in Corydalis, spring ephemeral, group were studied during two years at Namhansansung area. Corydalis´ flower was out in the early April and its seed dispersed in the early May. The period of total seed production was 30 days. The decrease rate of sex organs was the highest between deflowering time and early fruiting time. The numbers of flower and seed per plant were in the range of 1∼13 and 0∼76, respectively. And the number of seed per fruit was from zero to twenty. In a plant, seed production was the most (11.8 seeds) in the lowest fruit and conspicuously decreased along the upward fruit. In the same plant, seed production was various by each year. The plants of small tuber size produced more seeds and those of large tuber size produced fewer seeds in the next year than this year. In the early growth season, the flowering plants/total plants rate increased in proportion to plant size (tuber volume), the rate of the smallest size class (<100 ㎣) was in the range of 5.0%(1999)∼5.4%(2000), those over the 600 ㎣ size classes were 100%. The number of flower per plant at the same size class were higher in 2000 than in 1999. Especially, at the size class of 900 ㎣≤, the numbers of flower per plant were 13.2 in 2000 and 6.5 in 1999. In the late growth season, the flowering plants/total plants rates were 13.3%in the smallest size class (<100 ㎣)and 100% over the 500 ㎣ size classes. Therefore, the flowering plants/total plants rates along the size classes were higher in the late growth season than in the early one. The bumer of fruit or seed per plant increased in proportion to the volume and dry weight of tuber, there was not significant and varied along each plant in the same size class. The number of fruit or seed per plant conspicuously increased in proportion to the leaf area. Therefore, it was thought that seed production was related to photosynthetic ability during growth season.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.4
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• pp.327-332
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• 2010

This study was conducted to overcome the deliciousness by sex reversal in hemp plants. When female plants grown under long day length condition were transferred to short day length condition in 3th and 6th leaf stage, a few male flowers were formed and the gap of flowering days between sex reversed male and normal female flowers were around 10 days and 3 days, respectively. Although the flowering amounts were small, this short gaps of flowering days were enough for artificial pollination. When female plants grown under long day length condition were transferred to short day length condition just after treatment of silver nitrate in the vegetative stage, a great amount of male flower was formed and the gap of flowering days between sex reversed male and normal female flowers were only 1 to 3 days. The increased sex reversed male flowers and induced short gap of flowering days were adequate for natural wind pollination. When female seeds were cultivated, seed yield was 141 kg/10a, while it was 96 kg/10a when normal seeds cultivated.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.3
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• pp.67-74
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• 1979

Peanut was cultured with varying planting density and sowing date with and without vinyl-film mulching. Vinyl-film mulching raised soil temperature 4.6$^{\circ}C$ higher than the non-mulched during April and early May, but later-on the soil temperature was similar between the two treatments. The ripening and slender grain ratio increased with closer spacing and earlier sowing. Compared with ordinary cultural practices of May 10th sowing without mulching the peanut yield increased by 9% by mulching sown May 10th, and by 49% by mulching and early sowing April 20th.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.65-65
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• 2020

우리나라의 잇꽃 재배는 2010년 39ha 수준이 재배되다가 2014년에는 76ha 까지 확대되었으나 점차 감소하는 추세를 보이고 있으며 2018년에는 55ha가 재배되고 있는 것으로 보고되었고 주산지는 전라남도와 경상북도로 알려져 있다. 잇꽃(Carthamus tinctorius L.)은 국화과에 속하는 두해살이 초본 식물로 한자명은 홍화(紅花), 영명으로는 Safflower를 사용하고 있다. 우리나라에서 잇꽃 이용은 잇꽃 종실을 위주로 이용되고 있으나 일본의 경우 잇꽃의 경관적 가치를 활용하여 산형현(山形縣)에서는 홍화축제가 매년 개최되고 있으며, 미국 등에서는 잇꽃의 저온 압착유가 기능성 건강식품류로 판매되고 있다. 본 연구는 차광 조건에 따른 잇꽃의 개화특성 및 종자의 지방산 조성을 조사하여 일조시수가 짧은 준고랭지에서 잇꽃의 적응성을 평가하기 위해 수행되었다. 차광조건별로 개화기의 엽면적을 조사한 결과 30% 차광조건에서 9041.0mm²로 무차광에 비해 높아지는 양상을 보였고 50% 이상의 차광에서는 유의하게 낮아지는 경향을 나타냈다. 식물체의 초장은 50% 차광에서 낮아지는 양상이었으며, 주경의 착엽수는 30%와 70% 차광조건에서 18.3매/주 이상으로 증가되는 경향을 보였다. 화서별 착화수에서는 1차 화경 및 2차 화경 모두에서 30% 차광조건에서 착화수가 높은 경향을 나타냈으며 70% 차광조건에서는 2차화경 착화수가 유의하게 낮아지는 경향을 보였다. 차광 조건별로 잇꽃의 개화단계를 비교한 결과 동일한 조사시기에 무차광에서는 개화 3단계의 만개기까지 도달한 비율이 51.6%로 높았으나 50% 이상 차광에서는 11.1%로 낮아 개화가 지연되는 결과를 보였다. 차광조건에 따른 종자의 100립중은 무차광에서 4.9g의로 유의하게 높았으며 차광 비율이 높아질수록 낮아지는 양상이었고 단윔녀적당 종자 수량에서도 무차광이 201.1kg/10a를 보인 반면70% 차광에서는 86.6kg/10a의 낮은 수량을 보였다. 잇꽃 종자의지방산 조성에서 조지방 함량은 18.1~18.6% 범위로 차광조건에 따른 유의한 차이는 없었으며 palmitic acid의 함량은 무차광에서 5.35%로 높았으나, oleic acid의 함량은 30% 차광조건에서 10.2%로 무차광에 비해 높아지는 양상을 나타냈으며 linoleic acid는 50% 차광조건에서 83.6%로 가장 높은 비율을 보였다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.3
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• pp.256-261
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• 1994

To investigate the effects of topping method on the yield and major agronomic traits of three varieties differed in plant type of Hibiscus manihot the experiments were carried out Mokpo Branch Station of Crop Experiment Station, in 1993. Fresh weight of root, dry weight of culm, dry weight of capsule and dry matter ratio on root were highest in the long culmed variety, and at the plots with topping of growing point in main culm and branches(Treatment No.3). Considering from the above results, optimum topping method seemed to be topping of growing point in main culm and branches in the long culmed variety.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.1
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• pp.55-59
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• 1993

Essential oil components and contents were investigated at different growth stages and organs of Schizonepeta tenuifolia Briquet. The content of essential oil different by growth stages and organs and the amount of essential oil at leaf was higher than any other organ. The content of essential oil at leaf and spica were increased by long growth period. The d-menthone and l-pulegone were maj or components of essential oil and contain 51-76% of total essential oil at leaf and spica. In the early stage leaf. l-pulegone was major component of essential oil but d-menthone was major components in the late stage leaf.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.379-383
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• 2008

Oviposition preference of the bean bug, Riptortus clavatus to sites on a plant and within a field, to plants at different developmental stages, and to different leguminous germplasms was observed. The insect layed its eggs mainly on the back surface of leaf in the upper half of plant in both observation from oviposition cage and soybean field. The egg number in fields were observed at a statistically-same rate in marginal and inside area, and at a median value of one egg per leaf in oviposited leaves. Full seed stage of soybean hardly affected oviposition preference of the insect. A statistically-significant difference in oviposition to different leguminous germplasms was observed.

• Korean Journal of Medicinal Crop Science
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• v.13 no.4
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• pp.186-189
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• 2005

Plant flowering should be mainly affected by temperature and daylength. The study was carried out to measure the effect of temperature during winter on growth and floret flowering of Orostachys japonicus grown under 2 hour night break. Temperature was controlled above $10^{\circ}C$ and $20^{\circ}C$ as heating boilers were run below them to compare the natural temperature. Night-break treatment was done on August 25 and afterward samples were taken every 4 weeks to check growth, morphological and flowering related characters. Plant height, inflorescence length, number of leaves including bracts and stem diameter were increased in heating temperatures of > $10^{\circ}C$ compared to natural temperature although similar in the two heating ones. Leaves and bracts, florets, stem, root, shoot and total dry weights showed the same response as the above morphological and flowering related characters. Florets were more formed but less flowered with higher temperatures. Anthesis rates of individual plant were 100% in natural temperature, 25% in > $10^{\circ}C$ heating temperature but none in > $20^{\circ}C$ heating temperature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.5
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• pp.431-436
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• 1994

The objective of experiment was to investigate the effects of sowing dates on forage yield and growth characteristics of rye in paddy field cultivation in midwest region of Korea. The field experiment treated with 5 levels of sowing dates was carried out at Yesan from october 1990 to june 1991. The field emergence rate and winter survival rate were decreased with delay in sowing dates by the days from sowing to emergence were took a long period of time. The crop growth rate were increased with early in sowing date. The fresh and dry weight of rye were increased with early in sowing date, but there was no significant differences between sowing date from Oct. 5 to Oct. 25. The highest fresh yield was obtained at flowering stage and the highest dry yield was obtained at milky stage. The ratio of leaf blade and leaf sheath in rye plant were decreased with earlier sowing date and delayed harvest, but the ratio of stem and inflorescence was vice versa.

• Korean Journal of Plant Tissue Culture
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• v.21 no.4
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• pp.233-237
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• 1994

Plant regeneration system via somatic embryogenesis in leaf explant cultures of Gentiana scabra var. buergeri has been established. Leaf segments formed calli when cultured on MS medium supplemented with 0.5 mg/L 2,4-D and 2 mg/L BAP After transferred to SH medium supplemented with 0.5 mg/L 2,4-D, 2 mg/L CPA and 0.5 mg/L kinetin, the callus became embryogenic. The embryogenic callus was subcultured every 3 to 4 weeks. Upon transfer onto SH basal medium the embryogenic callus gave rise to numerous somatic embryos, which subsequently developed into plantlets. The regenerated plants were potted in an artificial soil with mixture (peatmoss : pearlite : vermiculite : 2 : 1 : 1) and transplanted to the soil after kept under a high humidity for two weeks. A total of 78 plants out of 105 regenerated plants survived in the soil. Phenotypic variations in height, number of stems and the flowering time were observed in tile regenerated plants. Cytogenetical analyses showed no chromosomal variation.