• Korean Journal of Weed Science
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• v.6 no.2
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• pp.174-190
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• 1986

A series of laboratory and greenhouse experiments were conducted to find out the possibility of tissue culture and cell culture methods as a tool to study herbicidal behaviour and herbicide tolerance screening from 1985 to 1986 at the Yeongnam Crop Experiment Station. For dehulled-rice culture, pure agar medium was the most appropriate in rice growth campared to other media used for plant tissue culture method. All the media but the pure agar medium resulted in growth retardance by approximately 50% and this effect was more pronounced to root growth than shoot growth. Herbicidal phytotoxicity was enhanced under light condition for butachlor, 2.4-D, and propanil while this effect was reversed for DPX F-5384 and CGA 142464, respectively. And also, herbicides of butachlor, chlornitrofen, oxadiazon, and BAS-514 resulted in more phytotoxic effect when shoot and root of rice were exposed to herbicide than root exposure only while other used herbicides exhibited no significant difference between two exposure regimes. Similar response was obtained from Echinochloa crusgalli even though the degree of growth retardance was much greater. Particularly, butachlor, 2.4-D, chlornitrofen, oxadiaxon, pyrazolate and BAS-514 totally inhibited chlorophyll biosynthesis even at the single contact of root. Apparent cultivar differences to herbicide were observed at the young seedling culture method and dehulled rice cultivars were more tolerant in DPX F-5384, NC-311, pyrazolate and pyrazoxyfen, respectively. For derant than other types or rice cultivar in butachlor, pretilachlor, perfluidone and oxadiazon while Tongil-type rice cultivars were more tolerant in DPXF-5384, NC-311, Pyrazolate and Pyrazoxyfen, respectively. For dehulled rice culture, on the other hand, Japonica-type rice cultivar was less tolerant to herbicides of butachlor, propanil, chlornitrofen and oxadiazon that was reversed trend to young seedling culture test. Cultivar differences were also exhibited within same cultivar type. In general, relatively higher tolerant cultivars were Milyang 42, Cheongcheongbyeo, Samgangbyeo, Chilseoungbyeo for Tongil-type, Somjinbyeo for Japonica-type and IR50 for Indica-type, respectively. The response of callus growth showed similar to dehulled rice culture method in all herbicides regardless of property variables. However, concentration response was much sensitive in callus response. The concentration ranges of $10^{-9}M-10^(-8)M$ were appropriate to distinguish the difference between herbicides for E. crusgalli callus growth. Among used herbicides, BAS-514 was the most effective to E. crusgalli callus growth. Based on the above results, tissue culture method could be successfully used as a tool for studying herbicidal behaviour and tolerance screening to herbicide.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.283-290
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• 2014

This experiment had been conducted to determine optimal culture conditions for the growth and cut flowers of Calla (Zantedeschia 'Black Magic' 'Golden Affair') in highlands. Tubers of calla 'Black Magic' was treated with 0, 100, and $200mg{\cdot}L^{-1}$ concentration of $GA_3$. ABA content in tubers and roots were twice higher ($20-25pmol{\cdot}mL^{-1}$) in control than in $GA_3$ treated tubers and roots. ABA contents in tubers was not consistent but ABA contents in roots increased with increasing $GA_3$ concentration. However ABA is in inverse proportion to GA. It was mean that GA of high contents was ABA of low contents. Calla 'Golden Affair' was treated with different mulching materials (Control, black PE, Reflective film, Rice hull) and $GA_3$ concentrations (0, 50, 100 and $200mg{\cdot}L^{-1}$). It was largest in the length of flower at mulching of reflective film, Rice hull and it was greatest in the number of cut flowers at the treated with $200mg{\cdot}L^{-1}$ $GA_3$, Therefore the proper condition was at $200mg{\cdot}L^{-1}$ $GA_3$ with reflective film mulching.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.3
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• pp.257-262
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• 1981

Field experiment with 0, 100, 200, 400, and 800 kg-N/ha-year application levels was carried out to study the nitrogen response in the early stage of orchardgrass pasture establishment at College Fann, SNU, in 1979 and 1980. Both the highest dry matter yield and maximum percent of N recovery were obtained at the same level of 200 kg-N/ha in the year of seeding. but those of the next year were obtained at 400 kg-N/ha level. Leaf area indices (LAI) and net assimilation rates (NAR) during each regrowth periods as well as total nitrogen contents of forage at each cutting time increased with applied N in both years. The maximum crop growth rate (CGR) over two years was estimated to be obtained when LAI reached to about 5. The accumulation of NO_3 -N in forage started from 400kgㆍN/ha application in 1980. and exceeded the safe level for ruminants at the level of 800 kg-N/ha.

• Korean Journal of Medicinal Crop Science
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• v.7 no.4
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• pp.257-262
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• 1999

We investigated the biological activities on ethanol extracts of R. glutinosa and R. glutinosa Preparata. The result of anti-mutagenicity suggested that the ethanol extract of R. glutinosa Preparata showed stronger activity than that of R. glutinosa ethanol extract. All of the ethanol extracts showed over 50% growth inhibition of several cancer cell lines. Especially, 61% of the cell growth of Hep3B was inhibited by adding 1g/ l of ethanol extract of R. glutinosa Preparata. In hypoglycemic activities and controlling blood pressure, 63.69% of ${\alpha}-glucosidase$ and 56.58% of ACE activities were inhibited by adding 1g/ l of ethanol extract of R. glutinosa Preparata. In general, the ethanol extract of R. glutinosa Preparata showed higher biological activities than those of R. glutinosa.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.1
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• pp.55-58
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• 1999

Plant water status during growth is directly and indirectly associated with seed yield. The objective of the present study was to determine the genotypic differences in leaf water characteristics at an early growth stage of soybean [Glycine max (L.) Merrill] plants through the pressure-bomb technique. Measurements of water potential as well as relative water content (RWC) were made at the third leaf from the fully-expanded top leaf of eight different soybean genotypes grown for 31 to 35 days after field emergence. On the basis of the modified exponential model, pressure-volume (PV) curves were fitted well ($R^2$=0.92＊＊ to 0.99＊＊ for the curvi-linear region and R=0.67＊＊ to 0.96＊＊ for the linear region), indicating that a segmented model using PROC NLIN of SAS could be used effectively to estimate the leaf water characteristics. The regression analysis for the pressure-volume (PV) curve revealed genotypic variation in the solute potential at saturation (Ψ$_{s,sat}$ :-10.7 to -14.8 bar), solute potential at incipient plasmolysis (Ψ$_{s,ip}$ : -14.3 to -18.3 bar), RWC at incipient plasmolysis (RW $C_{ip}$ : 83.3 to 91.7%), high integrated turgor pressure from saturation to plasmolysis ( $_1$$^{b}$ : 0.39 to 0.81), and maximum volumetric modulus of elasticity ($\varepsilon$$_{max}$ : 150 to 445 bar).).

• Korean Journal of Weed Science
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• v.4 no.1
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• pp.62-68
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• 1984

This experiment was conducted to find out the possibility for reducing herbicidal dose of the recommended herbicides in combining with the plant growth regulator "chlorflurenol" at the Yeongnam Crop Experiment Station, from 1981 to 1982. Chlorflurenol itself exhibited weed suppression effect against Monochoria raginalis Presl., Rotala indica Koehne, Cyperus difformis L., Lindernia procrembens Philcox, etc. and its effect increased as the concentrations of chlorflurenol increased from 100 to 1,000 ㎖/㏊. Combination of chlorflurenol with butachlor or thiobencarb, showing synergistic effect, reduced their recommended herbicidal rates by 50 to 75%, showing 90% of weed control rate, stic but combined treatment between chlorflurenol and bentazon showed an antagonistic effect since bentazon had poor control ability to Echinochloa crusgalli Beauv. An application of chlorflurenol showed no significant effect on rice growth, in terms of dry weight, but it resulted in the decrease in the ratio of leaf blade to other non-photosynthetic organ.

• Korean Journal of Medicinal Crop Science
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• v.7 no.3
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• pp.218-228
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• 1999

This study was conducted to obtain the information on dry matter productivity in Angelica gigas Nakai for establishing the cultivation method. Cultivation methods such as direct seeding on Mar. 31, Apr. 15 and Apr. 30, and transplanting of $8^{\frac{1}{2}}$, 9, 12 months old seedling were investigated. There were similar tendencies in changes of agronomic characters for all cultivation methods. Dry weight started to increase from 120 DAS. Direct seedling showed vigorous growth for aerial part, whereas transplanting showed better underground part. The quadratic polynomial was suitable to dry weight of root after 120 DAS (or DAT) .Short growing time had higher RGR and NAR independent of cultivation method but Direct seeding on Mar. 31 and transplanting of 9 months old seedling had the highest CGRs. LAI was positively correlated with CGR, and CGR had the highest value as $6.74\g/m^2/day$ when LAI was 1.97. RGR and NAR increased as mean temperature was increased and showed the highest value around . The highest net production of leaf and petiole was obtained at 20 and$23^{\circ}C$, respectively.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.92-92
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• 2022

In preparation for the ever-changing climate and unification of North Korea and South Korea, it is necessary to increase the grain self-sufficiency rate by selecting crops with good utilization in high-altitude regions. The principle is to sow pastures at the end of August. However, sowing occurs in spring because the sowing period is missed when the weather is bad or when the workforce is insufficient. Sometimes when the grassland is completely devastated, it is frequently sowed in spring. In addition, North Korea consists of a high-altitude regions, and has been devastated in a general mountainous region. As a result, the landscape is not good and it is vulnerable to natural disasters such as landslides. Therefore, to prevent this, pasture must be sowed in the high-altitude regions. The goal of this study was to evaluate and compare yield and feed value of pasture species and varieties by spring sowing in high-latitude regions. The study was conducted in Pyeongchang, Gangwon-do, which is 700m height above sea level. The pasture species and varieties was sown on April 24, 2022. Each treatment was carried out by sowing 30 kg/ha, the experiment field size was 1 m²(1m×1m), and randomized block design with tri-repeat. The total of 14 varieties was used in the study, 6 varieties of Orchardgrass (OG), 6 varieties of Tall fescue (TF) and 2 varieties of Perennial ryegrass (PRG). The grassland composition fertilization using (N:P₂O₅:K₂O at 80:200:70 kg/ha) was conducted and management fertilizer was N:P₂O₅:K₂O at 210:150:180 kg/ha. The first harvest was June 26,2022 and the second harvest was on August 16, 2022. For statistical analysis of the data, an Analysis of Variance (ANOVA) was performed using the R3.6.3 software program, and all data was subjected to analysis using Duncan's multiple range test. Significance was set at the 5% level. The dry matter yield at the first harvest was the highest in PRG, and second harvest was the highest in TF (p < 0.05). Overall, PRG showed a trend of gradually decreasing growth, OG and TF showed a trend of gradually improving growth. This showed that PRG was considerably weaker to summer depression than other pasture species. Comparing the total dry matter yield, TF was the highest (4,565.45 kg/ha), but there was no significance difference with PRG (4,487.24 kg/ha) (p < 0.05). In addition, comparing the total TDN (total digestible nutrient) yield, TF was the highest (3147.33 kg/ha), second in PRG (2975.67 kg/ha) and third in OG (2052.33 kg/ha). Since this result is the data of the second harvests, if the result is derived by the end of next year, it will be provided as basic data for selection of pasture species and varieties suitable for spring seeding in high-altitude regions.

• Korean Journal of Medicinal Crop Science
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• v.4 no.2
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• pp.157-162
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• 1996

Experiments were conducted from 1994 to 1995 to understand the effects of the labor-saving seeding and planting density on growth and root yield of Astragalus membranaceus. The drilling seeder reduced seeding time than the hand seeding; It takes 3. 5hrs/l0a to seed by drilling seeder while 33. 0hrs/l0a by hand seeding, which labor reducing rate was 89. 4 %. Emergence rate in the drilling seeder was increased 17% than in the hand seeding, so the root yield were increased 23% to 136. lkg/l0a in using drilling seeder compared to 110. 3kg in hand seeding. On the effect of planting density on the growth characteristics plant height was long in dense planting and stem diameter was thick in spacious planting. Root diameter and dry root weight root per plant were decreased in dense planting and root yield was highest in optimum planting densities $(6\;row\;(15cm)\;{\times}\;10cm)$ in the harvest of 1 year old plants in Astragalus membranaceus. The gross profit were increased 23% to 1,933 thousand won per l0a in the drilling seeder compared to 1,566 thousand won in the hand seeding, also the managing costs were reduced 18% to 406 thousand won per l0a in the drilling seeder than 494 thousand won per l0a in the hand seeding.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1445-1450
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• 2012

A study was conducted to evaluate effects of alfalfa meal on growth performance and gastrointestinal tract development of growing layer ducks to provide evidence for application of alfalfa meal in the duck industry. Two hundred and fifty-six healthy Shaoxing 7-wk old growing layer ducks were selected and randomly allocated to 1 of 4 dietary treatments based on corn and soybean meal and containing 0, 3, 6, and 9% of alfalfa meal for 8 wks. Each treatment consisted of 4 replicates of 16 ducks each. Briefly, birds were raised in separate compartments, and each compartment consisted of three parts: indoor floor house, adjacent open area and a connecting water area. The results showed: i) Growing ducks fed alfalfa meal diet were not significantly different in average daily gain, feed intake and gain-to-feed ratio from those fed no alfalfa diet (p>0.05). ii) Alfalfa meal increased the ratio crop, gizzard to live weight, caecum to live weight, the caecum index of growing ducks (p<0.05). iii) Villus height in duodenum and jejunum of growing ducks increased significantly with the increase of alfalfa meal levels (p<0.05). Crypt depth in duodenum and jejunum of growing ducks decreased significantly with the increase of alfalfa meal levels (p<0.05). This experiment showed that feeding of alfalfa meal to growing layer ducks could improve gastrointestinal tract growth and small intestinal morphology without effect on performance. This experiment provides evidence that alfalfa meal is a very valuable feedstuff for growing layer ducks.