• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.4
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• pp.511-520
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• 2014

Kenaf (Hibiscus cannabinus L.) was recognized as a potential source of forage. To reduce the production cost, we should insure large cultivation area. The one of the best candidate places to expand the useful kenaf production was 'Saemangeum' reclaimed land. To confirm the possibility of kenaf growth in reclaimed land, we seeding and cultivated the kenaf in 'Saemangeum'. The germination percentage of kenaf on 5.0 dS/m soil salinity was 18%. It is less 66% than that of 4.0 dS/m soil salinity and at 6.0 dS/m, the germination percentage of kenaf was under 10%. The growth and development of kenaf in reclaimed land grew worse with increasing soil salinity. The stem diameter which the most important factor that decide the value and yield of product was upper 2.6 cm when soil salinity maintained under 4.0 dS/m, but if soil salinity marked over 4.0 dS/m, the stem diameter of kenaf was drop under 2.0 cm and it deteriorate the number of leaves per plant by 20~46%. The necrosis on older tip and marginal leaves were noted approximately first month after seeding which was correlated directly with the salinity levels of reclaimed soil. Reduction of total yield was coincide with increasing levels of EC. If soil salinity over 5.0 dS/m, the amount of decreased by soil salinity was 51% than that of non-reclaimed region. The allowable soil salinity level of which could be maintained within 20% reduction rate was 4.2 dS/m. Consequently kenaf can be grown successfully with moderately saline soil condition. However, salt levels in excess of 4.2 dS/m severely have restricted plant growth and development and will result in significant yield reduction.

• Journal of Bio-Environment Control
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• v.18 no.4
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• pp.502-507
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• 2009

This study was conducted to establish the minimum harvesting time of 'Campbell Early' grape with girdling of 8 years old vines by the investigation of fruit quality. Girdling was performed as 5~7mm width at 1.0m height with a Y-trellis system on July 5th at Gimcheon, Gyeongbuk province. Skin color, soluble solids contents, sugar content, organic acid, and titratable acidity were analyzed every seven days period after the girdling. From 14 days after the girdling, pericarp color changed quickly as compared to the control, and also decreased b value and increased a value of Hunter L were observed. The content of organic acids decreased quickly as 0.85% as compared to the control's one, 1.10%. Sugar-acid ratio increased rapidly from the 21days as 15.1 against 10.8 of the control at harvesting time. After 14days, sugar content was abruptly increased such as fructose and glucose, that is 7days faster than the control. In harvesting time, their contents were high as $64.5mg{\cdot}g^{-1}FW$ and $61.0mg{\cdot}g^{-1}FW$ as compared to $56.1mg{\cdot}g^{-1}FW$ and $53.7mg{\cdot}g^{-1}FW$ of the control respectively. Among the content of organic acids, malic acid decreased quickly than the control's one in coloring time. The content of tartaric acid was obviously lower as $4.13mg{\cdot}g^{-1}FW$ than the control's one, $5.96mg{\cdot}g^{-1}FW$ in harvesting time. From these results, we assume that the harvesting of girdled 'Campbell Early' grape should be started in 42days after the girdling, when sugar-acid ratio is above 15.

• Korean Journal of Plant Resources
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• v.21 no.1
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• pp.1-4
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• 2008

The clonal variation in female flowering was studied in Larix leptolepis clone bank, consisting of 116 clones, for three years. The between-year variation was large; i.e. the percentage of flowering grafts and average number of flowering per graft were $28.4{\sim}67.2$ and $9{\sim}176$, respectively. Differences in flowering abundance among clones were large and statistically significant in all the years studied. The variance of flowering abundance among clones was increased when flowering was poor. The average of broad-sense heritability of flowering abundance was 0.52. The genetic gain(%G) was estimated at 57.4% when the upper 30% clones were selected. The clonal stability of flowering abundance was compared using average number of flowering and coefficient of variance value of each clone. The clones such as Gyeonggi 9(29), Kangwon 37(137), Chungnam 6(46), Chungnam 14(414), R11, R8 showed abundant flowering and high stability.

• Journal of Bio-Environment Control
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• v.17 no.3
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• pp.231-237
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• 2008

Objective of this research was to investigate the effect of calcium concentrations in the fertilizer solution on growth and development of Ca deficiency in 'Maehyang' strawberry (Fragaria $\times$ ananassa Duch.). The margins of the youngest leaves were scorched and they developed a cupped shape as they were expanded in Ca deficient plants. The vein area of the youngest leaves became brown when the deficiency became severe. The quadratic responses were observed in dry weight production to elevated Ca concentrations in fertilizer solutions with the highest growth in 4.5 mM treatment. The regression equation was y=2.4026+1.0209x-$0.098x^2$ $(R^2=0.3546^{***})$. However, tissue Ca contents increased lineally as the Ca concentrations in fertilizer solutions were elevated (y=1.2108+0.1333x, $R^2=0.9189^{***}$). In changes of the fresh weight and Ca concentrations in petiole sap, fresh weight production showed quadratic responses to elevated Ca concentrations in fertilizer solution, but Ca concentration increased lineally. The equations in changes of fresh weight and Ca concentrations were y=9.273+4.882x-$0.4245x^2$ $(R^2=0.4935^{***})$ and y=52.311+3.2917x $(R^2=0.6918^{***})$, respectively. When the concentration of calcium at which plant growth was retarded by 10% is regarded as critical concentration level, the calcium contents based on dry weight of above ground plant tissue and in petiole sap should be in the range between 1.6 to 2.25% and 63 to $79mg{\cdot}kg^{-1}$, respectively.

• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.129-150
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• 1985

The present investigation was conducted to provide a systematic approach necessary to establish an integrated insect pest management program of barley in Korea. Some ecological surveys on insect pests of barley have been undertaken at the field of Experimental Station, Ky$\check{o}$ngbuk Provincial Office of Rural Development as a fixed point survey area, and at 23 localities for round survey throughout southern and central Korea from 1983 to 1984. Previously known insects injurious to barley in Korea were revised and the population dynamics of 10 dominant harmful species were analyzed according to either 24 localities or 25 cultivars respectively by using several sampling methods of net sweeping, black light traps, yellow water pan traps and visual counting. As the results, a total of 94 species belonging to 77 genera under 32 families are known to be injurious to barley, among them 20 species are newly added here. In the population density level, the dominant species were disclosed as Laodelphax striatellus (43.1 %), Macrosiphum avenae(27.0 %), Rhopalosiphum padi(6.5 %), R. maidis(5.4 %), Psammolettix strialus(2.7 %), Chlorops oryzae(2.2 %), Agromyza albipennis(2.1 %) Phyllotreta nemorum(1.4 %), Chaetoenema cylindrica(1.0 %), Dolycoris baccarum(1.0 %) in order. For the general abundance of major insect pests, it was highest in the cultivar P'aldal whereas lowest in Milyang #22. There were tendencies that Psammotettix striatus, Dolycoris baccarum, Phyllotreta nemorum and Chaetocnema cylindrica represented a maximum increase in the beginning of June, while Chlorops oryzae and Agromyza albipennis showed in the middle of May but aphids were in the end of May. In the dominance of natural enemies, Nabis stenoferus occupied 21.4 % and Propylaea japonica 9.6 %.

• Weed & Turfgrass Science
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• v.6 no.1
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• pp.21-27
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• 2017

This study was investigated in order to occurrence of weed flora in orchard (apple, grape, peach, pear etc.) fields and to the establishment of weed control basic data in these weeds. And this study was survey on 2015. As a result of the study on orchard weeds, there were total of 492 weeds including 63 families. Among all the weeds, 159 species were annual, 97 species were winter annual and 236 were perennial. Each fruit tree patterns of occurrence weeds, 306 species 50 families in apple orchard, 304 species 50 families in pear orchard, 286 species 50 families in grape orchard, and 288 species 48 families in peach orchard. Dominance was the highest with Digitaria ciliaris followed by Artemisia princeps, Stellaria aquatica, Commelina communis, Acalypha australis etc. in order. And exotics weeds occurred 127 species. Trifolium repens was the highest in importance analysis and the followings were in order of Conyza canadensis, Chenopodium album, Taraxacum offcinale, Rumex crispus etc. Changes in weed vegetation in orchard during 30 years, did not very many changed. In 1990, D. ciliaris, Persicaria hydropiper, Portulaca loeracea were dominant. In 2003, D. ciliaris was the most abundant species, followed by A. australis, A. princeps species. And in 2015, also D. ciliaris was the most dominant, followed by A. princeps, S. aquatica.

• Horticultural Science & Technology
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• v.35 no.2
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• pp.170-177
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• 2017

This study was conducted to estimate the light pollution damage caused by night-break lighting in 'Kyoho' grapes. Night irradiation was performed every night for four hours (10 p.m. to 2 a.m.) from the full bloom to the harvest stage using red, blue, and white lamps as artificial light. Fruit yield, soluble solid content, anthocyanin content, and chlorophyll a content were affected by night irradiation. The soluble solid content of the control was $17.5^{\circ}Brix$, approximately $1^{\circ}Brix$ higher than the red ($16.4^{\circ}Brix$), blue ($16.2^{\circ}Brix$), and white light treated grapes ($16.3^{\circ}Brix$). The anthocyanin content of the skin was also higher in the control at $4.08{\mu}g{\cdot}cm^{-2}$ compared to the red ($3.14{\mu}g{\cdot}cm^{-2}$), blue ($2.47{\mu}g{\cdot}cm^{-2}$), and white ($2.82{\mu}g{\cdot}cm^{-2}$) light treated samples. On the other hand, the chlorophyll a content of the control was the lowest at $0.268{\mu}g{\cdot}cm^{-2}$ as compared with the red ($0.339{\mu}g{\cdot}cm^{-2}$), blue ($0.345{\mu}g{\cdot}cm^{-2}$), and white ($0.372{\mu}g{\cdot}cm^{-2}$) light treated samples. Considering that higher soluble solid contents, higher accumulation of anthocyanin, and lower chlorophyll a contents are factors involved in fruit maturation, night irradiation may delay fruit maturation and red light treatment may result in decreased yield. Our results confirmed that night-break lighting regardless of the wavelength provoked light pollution in 'Kyoho' grapes. Therefore, fruit maturation may be poor in the presence of artificial light, including streetlamps, in neighboring vineyards.

• Korean Journal of Poultry Science
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• v.42 no.2
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• pp.181-189
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• 2015

The objective of this study was to investigate the effect of dietary supplementation of vitamin C and Sea buckthorn on the performance, blood biochemistry and meat quality in old laying hens. A total 200 Hy-Line Brown laying hens (101 weeks old) were randomly allotted to 1 of 5 dietary treatments : (1) Basal : basal diet, (2) Vit. C : basal diet + 0.1% vitamin C, (3) SB 0.1 : basal diet + 0.1% Sea buckthorn, (4) SB 0.5 : basal diet + 0.5% Sea buckthorn, and (5) SB 1.0 : basal diet + 1.0% Sea buckthorn. Each treatment was replicated 4 times with 10 birds units were arranged according to randomized block design. Feeding trial lasted 4 weeks under 16L:8D lighting regimen. The diets were fed to hens on an ad libitum basis for 4 weeks. Result indicated that during feeding trial of the experiment, hen-day egg production and feed conversion ratio were not significantly influenced by treatments. However, feed intake was significantly (P<0.05) higher in Vit. C and SB treated groups than the basal during 1 wks and 3 wks. Egg weight was significantly (P<0.05) higher in basal and Vit. C than the SB 1.0 treatment. There were no differences in carcass yield during feeding trials. However, partial ratio (breast and neck) was significantly (P<0.05) higher in SB 0.5 than other treatment. There were no differences in the level of leukocytes and erythrocytes. There were no significant differences on proximate analysis (DM, crude protein, crude fat, and crude ash), meat color, water holding capacity, cooking loss, and fatty acids concentrations. In conclusion, dietary supplementation of vitamin C and Sea buckthorn to the diet of old laying hens might be a potential ingredient for increasing partial weight (breast) in old laying hens.

• Journal of Korean Society of Forest Science
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• v.104 no.3
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• pp.337-351
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• 2015

The articles, published in the Journal of Korean Forest Society from Volume 1 (1962) to Volume 102 (2013), were investigated for the research trend analysis about forest plants for special purposes, i.e., edible plants, medicinal plants, feed resources, landscape plants, fiber plants, industrial usage, bee plants, bioenergy/phytoremediation uses, dye materials, and rare/endangered/endemic plants. These research articles were classified again based on the contents of research into following categories - habitat environment, ecology, physiology, propagation, silviculture (including planting and tending), genetics and breeding, identification, pest and disease control, animal-related research, components analysis and extracts, vegetation survey, biotechnology, management, recreation and forest healing, and research review. Among the total 2,433 articles published, 611 (25.1%) were related to plants for special usage or purposes. The highest frequency (14.9%) in publications was found in the field of silviculture followed by physiology, propagation, identification, and genetics and breeding, respectively. On the bases of usage, edible plants showed higher frequency (26.5%) than others, followed by industrial purpose, bioenergy/phytoremediation usage, landscape plants, medicinal plants, and rare/endangered/endemic plants. Populus plant species was the most popular in research, showing 62 articles; and Castanea crenata 36; Pinus koraiensis 35; Robinia pseudoacacia 20; Ginko biloba 17, etc. Based on the survey and analysis, the following points are suggested: 1) improved evaluation of forest plants as non-wood resources, 2) expanding research topics on the basis of production, management, and utilization of non-wood forest resources, 3) management of database of forest plant information and encouragement needed to strengthen cooperative researches satisfying the needs of other industrial and scientific areas, and 4) encouraging to promote traditional knowledge based research on forest plants.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.3
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• pp.205-216
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• 2010

Few spring sowing have been conducted on winter cereal crops for whole-crop silage use. Experiments were conducted during 2007 and 2008 at the Chungnam Agricultural Research & Extension Services. The objectives of this study were compared the spring sowing with the optimum season's sowing on growth, yield and feed quality in five winter cereal crops. The treatments consisted of 5 winter cereal crops, Youngyang (Barley, Spring habit I), Keumkang (Wheat, Spring habit II), Gogu(Rye, Spring habit estimated III), Shinyoung (Triticale, Spring habit estimated III), Samhan(Oat, Spring habit estimated II), and 3 planting dates, 18 October (optimum season's sowing), 23 February and 10 March in spring. Heading days as affected by spring sowing compared to optimum season sowing were delayed by 16~20 days in barley, wheat, rye and triticale, and 9 days in oat. The clipping dates at the optimal harvesting stage of each crop for round-baled silage in spring sowing was 8 June (yellow ripe stage) in barley, 25 May (10 days after heading) in rye, and 17 June in wheat (yellow ripe stage), triticale (milky stage) and oat (milky stage). The accumulative temperature from emergence to heading was significantly decreased as affected by spring sowing compared to optimum season's sowing, but that of sowing to emergence and that of heading to maturing was similar. The rate of spikes per tillering surveyed at each clipping date was 62.0-73.1 percent in barley, wheat, triticale and oat, and 56.0 percent in rye compared to that of optimum season sowing. The dry matter yield in spring sowing compared to 18 October was obtained about 71.7 percent in barley, 60.6 percent in wheat, 46.2 percent in rye, 70.2 percent in triticale and 110.9 percent in oat. It were increased in acid detergent fiber (ADF), neutral detergent fiber (NDF) and crude protein content, but decreased in digestible dry matter content(DDM) and relative feed value (RFV). The yield of DDM by spring sowing was decreased in barley, wheat, rye and triticale, but increased in oat. The yield of dry matter and DDM were higher in oat and triticale than that of barley, wheat and oat. So, regardless to clipping dates and cropping system, the appropriated crop for spring sowing was oat, and subsequently triticale and barley. It was not adopted for spring sowing in rye because of low rate of no. of spikes per tillers and yield. It was necessary eliminated winter growing nature by earlier sowing at the late of February after overwinter.