• Proceedings of the Korean Society of Crop Science Conference
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• 2022.04a
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• pp.77-77
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• 2022

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.04a
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• pp.53-53
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• 2022

• Proceedings of the Korean Society of Crop Science Conference
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• 2021.10a
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• pp.70-70
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• 2021

• Journal of Korean Society of Forest Science
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• v.77 no.4
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• pp.414-420
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• 1988

This research was performed to estimate the degree of influence of relative light intensity and planting density on the weight growth in the trans-planting bed. The Piuns koraionsis seedlings treated for different degrees of shading on seed bed were planted in transplanting bed. 1. The seedling weight growth under 100% relative light intensity and $6{\times}6$ plot(36 individual) density showed the largest growth and the best growth was found during 26th of May 25 of June. 2. As the relative light intensity decrease and with planting density increased, the weight growth decreased. And the weight growth had a tendency to decrease after 26th of May-25th of June. 3. T/R ratio showed the highest value under 63% relative light intensity and $12{\times}12$ plot (224 individual) of planting density. The highest T/R ratio was found during 26th of July-25th August.

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.350-357
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• 2014

BACKGROUND: Deicers such as calcium chloride ($CaCl_2$) and sodium chloride (NaCl) in Korea have been commonly used to reduce traffic accidents as well as injuries. However there have been adverse effects of deciders such as pollution of water and soil, and reduced productivity of agriculture as well as forest. This study aimed to investigate biological effects of the deicers against wheat, barley, and spinach. METHODS AND RESULTS: The germination of tested crop seeds exposed to chloride-deicers, $CaCl_2$ and NaCl was significantly reduced at over 3% concentration of chloride-deicers compared to the control. In spraying deicers to the seedlings of the crops, there was no symptom such as inhibition of growth rate or leaf elongation. However the germination of tested crop seeds was affected at 2% concentration of deicers when they were exposed continuously to deicers in soils. The growth of the shoot against $CaCl_2$ and NaCl treatments was very similar in wheat and barley whereas the shoot of spinach was the most susceptible. Based on these results, the sensitivity of the crops to the tested deicers was as follows: NaCl > $CaCl_2$ > mixture ($CaCl_2$ + NaCl). The length of shoots and roots of the seedlings grown in 1% treated soil was decreased. The biomass of all the seedlings decreased 1.5 to 4 times at 1%. CONCLUSION: These results indicate that the effects of salt deicers by inputting into soil against growing tested crops are more severe in germination and growth inhibition as well as biomass decrease.

• Weed & Turfgrass Science
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• v.7 no.2
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• pp.148-157
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• 2018

Research was initiated to evaluate four domestic and overseas organic soil amendments (SAs) on turfgrass groundcover and density and to provide basic information on practical sports turf establishment. This study was conducted in Agrostis palustris Huds. (CB) grown in sand-based root zone. A total of 20 treatments of SA+sand were prepared by mixing 10 to 50% (v/v). These amendments were SABP (Berger Peat), SAEP (Eco-Peat), SAGS (G1-Soil), and SAPP (Premier Peat). Turfgrass groundcover and density significantly varied with SAs, its mixing rate to sand and week after seeding (WAS). Cumulative turfgrass density was variable, but a great change occurred between 2 and 4 WAS. Turfgrass density at 2 WAS ranged from 36.7 (SABP 30) to 89.7% (SAGS 20), being 53.0% in differences among treatments. However, CB reached to carrying capacity around 6 WAS. Thus, most treatments were similar to 90% or so in density. At the end of study, overall groundcover ranged between 60.7 (SAEP 10) and 96.7% (SAPP 50). Proper mixing rate was variable with SAs, being 10 and 20% for SABP and SAGS, respectively. But the optimum rate was 50% for both SAEP and SAPP.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.3
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• pp.99-108
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• 2016

The shuttle breeding of Korean winter wheat has been able to develop high-yielding and day-length-intensive varieties with a wide range of ecologic adoption. However, the phenology of winter wheat has been changed due to recent rises in the winter temperature of Toluca and increasing frequency of high temperatures. We defined two wheat groups (group II and III) with vernalization and evaluated the impact of cold exposure duration and heading ratio due to changes in sowing dates by measuring changes in cold exposure duration and corresponding heading states of each group. The wheat cultivars were sown on three dates in two years. The cold exposure requirement of wheat sown on 6 November 2013 was unfulfilled. The cold exposure requirement of wheat sown on 22 November and 6 December 2013 was fulfilled. However, in 2014, the cold exposure requirement of wheat sown on 5 and 20 November was fulfilled, but that of wheat sown on 5 December was unfulfilled. The differences for the two early November sowings were because winter temperature rises, which caused high temperatures in 2013, whereas early November 2014 saw normal temperatures for the area. The heading ratio of group II did not show a clear difference among the three sowing dates, while the heading ratio of group III was reduced by about half. This implies that the efficiency of shuttle breeding of group III will be high since it showed strong sensitivity to changes in sowing dates. We calculated future sowing dates of each group under near future climate scenarios; the future available sowing dates of group II were projected, but the dates of group III were never estimated in the temperature rise scenario in Toluca. Our findings suggest that change of sowing dates should be considered in the strategy for shuttle breeding of Korean winter wheat.

• 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.

• Journal of Bio-Environment Control
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• v.13 no.1
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• pp.16-20
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• 2004

Aphis gossypii Glover(Homoptera: Aphididae) is an serious pest on various crops. This experiment was conducted to evaluate the effect of A. gossypii Glover on the growth of oriental melon and the plant recovery after removing A. gossypii. Visible damage symptom caused by A. gossypii feeding to oriental melon was leaf distortion and stunting. A. gossypii feeding for 20 days on oriental melon significantly reduced the growth of oriental melon with increasing A. gossypii density level. Plant growth was decreased by 63${\sim}$69%, 62${\sim}$88% and 49${\sim}$70% in plant height, leaf area and dry weight, respectively. During 10 day after aphids removal, the infested leaves remained stunt, however, new shoot and leaf recovered gradually. By 20 day, plant height, leaf area and dry weight substantially increased in 5 aphid per plant. Plant recovered rapidly with day and among aphid density level, 5 aphid per plant showed rapid recovery. When plant were infested with several density of aphid per plant, sugar contents of total leaves were not significantly different between aphid density level. Whereas, sugar contents of lear infested with aphid per leaf were decreased with increasing cumulative aphid-days.

• Korean journal of applied entomology
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• v.1
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• pp.42-46
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• 1962

1) The purpcse of the present study is to investigate the effects of culture filtrates of Fuarsium oxysporum f. vasinfectum which is known to produce wilt toxin (fusaric acid) on the germination of host plants (sesame, cotton) and non-host plants (wheat, rice). 2) The experiment on the germination of sesame, cotton, wheat and rice seeds in the seed beds separately added with culture filtr ates of 10 differential strains of Fusarium oxysporom f. vasinfectum demonstrated that culture filtrates of most strains of the fungus inhibit or retard the germination of seeds of 4 plants used in this study while those of a few strains do not give notable influence on the germination of seeds of those plants. a) Culture filtrates of strain 201 of the fungus strongly inhibited the germination of seeds of those plants in nearly same degree, but culture filtrates of the other strains, 281, 321, etc., showed remarkable differences in the toxicity inhibiting or retarding the germination of the seeds of those plants. b) In general, sesame seeds are greatly susceptible, wheat and cotton seeds are moderately susceptible and rice seeds are resistant to the toxicity of culture filtrates of the fungus. 3) In the soil containing a number of differential strains of Fusarium oxysporum f. vasinfectum, the germination of seeds and also the growth of seedlings of non-host plants are possibly checked by the toxic substance, fusaric acid produced by the fungus.