• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.1
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• pp.83-88
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• 2014

This research was carried out to determine the characteristics of germination in relation to temperature, and seedling emergence and growth affected by soil moisture in forage millet. The seeds of forage millet could germinate at more than $15^{\circ}C$ at the rate of 0, 90.5, 97.3 and 96.8% respectively 10 days after seeding at 10, 15, 20 and $25^{\circ}C$. The result showed that the temperature needs to be $15^{\circ}C$ or more for the seeds to germinate. The effects of seeding depth on the growth characteristics and emergence of millet seed were investigated in waters and direct seeding methods by thoroughly mixing the seed and soil. In water treatment, the emergence rates were 3.7% at $15^{\circ}C$, 7.6% at $20^{\circ}C$, 6.3% at $25^{\circ}C$, while direct seeding treatment showed the emergence rates of 65.6, 75 and 71% at 15, 20 and $25^{\circ}C$, respectively. At 15, 20, and $25^{\circ}C$, seeds in water seeding could germinate at 0.5, 1.8, 1.5 cm of soil depth, while in direct seeding, they could germinate at the depth of 9.5, 10.0, 9.9 cm. When the initial growth characteristics of the seeds were investigated, there was positive correlation between seeding depth and mesocotyl length in both water and direct seed methods. Growth and development in terms of leaf age, root length, coleoptiles and mesocotyl length, and plant height were found maximum at 0.5 cm soil depth for water seeding, and 3-5 cm soil depth for direct seeding. Results showed that there were close relationship among temperature, soil depth and moisture acquiring methods, and the combination of these factors greatly affected the initial growth characteristics and development of millet seeds. It can be concluded that, to get good seedling stand and germination of millet seed, millet should grown in field condition at the depth of 0.5 cm or less for water seeding, and 3-5 cm for direct seeding method.

• Korean Journal of Medicinal Crop Science
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• v.23 no.5
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• pp.379-384
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• 2015

Background : Considerable time and effort is required to develop new Panax ginseng varieties. Ginseng breeders have been developing techniques to shorten the breeding cycle to resolve this problem. In this study, we investigated the effects of adding $GA_3$ and alternating temperature (AT, $2^{\circ}C{\rightarrow}-2^{\circ}C{\rightarrow}2^{\circ}C$) on breaking bud dormancy in the varieties (Chungsun and Sunun) of ginseng root. Methods and Results : The $GA_3$ soaking treatment and AT were applied to one year old roots, which greatly accelerated the emergence of new buds. In one year old roots, new buds emerged from the 4th day post transplanting and after breaking dormancy with $GA_3$ and AT treatments. The emergence of new buds was completed within two weeks. The rate of bud emergence for Chungsun was 60% - 98% over 15 - 60 days after the AT and $GA_3$ treatments. The emergence rate of Sunun was 46% - 92%. Normal growth of the ginseng seedling was observed in spite of the early breaking of bud dormancy by combined $GA_3$ and AT treatments. Conclusions : $GA_3$ and AT treatments shortened the dormancy period and facilitated the stable emergence of ginseng seedlings. However, some plants suffered deformities and early sprouting owing to the combined $GA_3$ and AT treatments. Early sprouting was free from dormancy after leaf fall from the of aerial part of the plant.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.3
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• pp.183-189
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• 2021

We checked the emergence rate and early growth characteristics of young rice plants according to the germination length and seed damage ratio in direct seeding. The emergence rate was reduced according to the longer germination length and higher seed damage ratio. The emergence rate was further reduced under high-temperature conditions. The leaf number did not show a significant difference according to germination length and seed damage ratio. However, shoot and root dry weights were reduced according to the germination length and seed damage ratio. The root dry weight was highly correlated with the shoot dry weight. Based on these results, we concluded that a longer germination length and seed damage could induce the loss of nutrients and affect poor root growth, consequently inducing poor emergence and growth in the early growth stage of rice seeds. Therefore, in rice direct seeding, seed conditions of less than 1 mm of germination length should be checked for a sufficiently high standing rate and adequate growth characteristics after seeding.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.3
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• pp.224-232
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• 1990

This study was conducted to find out the improvement of water-logging injury which is an important factor of yield loss in sesame. Water-logging was treated at 10, 25, 40, 55 and 70 days after emergence for 24, 48 and 72 hours in sesame variety 'Ansanggae'. Some important agronomic characters were investigated after treatment. The important agronomic characters such as plant height, leaf area, dry matter weight, capsule setting stem length, number of capsules per plant, ripenning rate and 1,000 grain weight were most susceptible at 55 days after emergence by the water-logging treatment, and the longer period of water-logging, the more susceptible. Allmost of the useful agronomic characters were able to get over injury of water-logging only within 25days after emergence, but could not get it over since 40days. Grain yield was decreased due to the water-logging treatment by 69 to 86% in 55 days after emergence that is most susceptible stage for water-logging as compared with the untreated control which is 13g per pot, and the longer period of water-logging induced the lower yield. Oil content of grain showed significant decrease only in 55 days after emergence but the composition of fatty acid did not influenced by the water-logging.

• Korean Journal of Plant Resources
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• v.10 no.2
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• pp.140-144
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• 1997

This experiment was carried out to investigate the proper planting method of Rehmannia glutinasa Liboschitz. A Chungbuk local cultivar was sown on the seed bed of 200cm with the planting density of 30cm(6 rows) $\times$ 8.5cm(30 rhizome per $\textrm{m}^2$). The experimental design was randomized block design with 3 replications. And the result was summarized as follows. The emergence date of level Planting(control : 0$^{\circ}$) was May 23, but the emergence dates of Oblique planting(45$^{\circ}$) and Upright planting(90$^{\circ}$) treatments were later than the control by 2~4 days. And the leaf length and the ratio of leaf length/leaf width were not significantly different. As compared with the 29.2cm and 10.0mm of the rhizome length and the rhizome diameter of level planting treatment, the rhizome length of Oblique planting treatment was decreased by 3.4cm and 0 mm. The length and diameter of rhizome of the Upright planting treatment was decreased by 2.8cm and 1.0mm. And the order of sugar content was level Planting > Oblique planting > Upright planting. The total yields were decreased by 9% in the Oblique planting and by 15% in the Upright planting compared to 1,203kg/10a in the control, and the commercial yields showed the same tendency. The level planting treatment was found to be most proper for sowing of Rehmannia glutinasa Liboschitz in the middle inland region of Korea.

• Korean Journal of Medicinal Crop Science
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• v.2 no.1
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• pp.14-19
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• 1994

Elephant food(Amorphophallus konjac K.) have been utilized its tubers in workedmaterials for a health and diet food. The author supposed that it was increased the area of cultivation and demand. This experiments were conducted to select the proper covering material during winter in order to increase yield of tubers and decrease input by 2 year's continuous cultivation, also to verified ability of seed germination and to measured efficiency of photosynthesis of plant. The proper covering materials for wintering were rice straw and rice hull. These materials were covered at 5 cm thick and at field was promoted according to emergence appearing after winter. The yields were 5,790kg /10a at 4,730kg /10a, respectively. Yield increase was 120% and 80% than that of control. The seeds collected at August 22 were germinated about 84 percent, and it was not necessary to treatment of low temperature or germination-accelerated chemicals. The widest leaf area was ranged $1,218-1,438cm^2$ at October 20 and was varied. The efficiency of photosynthesis was highest at 65-95 days after leaf emergence. The line of broad leaf and high photosynthetic efficiency per unit area was greater compare with yield. Therefore, it was supposed that these characteristics will use a marker for selection for high-yielding lines.

• Korean Journal of Plant Resources
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• v.16 no.2
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• pp.118-122
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• 2003

These studies were carried out to clarify the effects of black P.E. mulching and planting density on the growth and rhizome yield of Jihwang #1, a new high yielding Rehmannia glutinosa variety. Emergence ratio was higher 3.1％ in mulching than in non-mulching, but was not affected by planting density. Plant height and fresh leaf weight per plant were increased by mulching and at lower planting density. However, the fresh leaf weight per unit area was increased at higher planting density. Dry rhizome weight was increased 28% in mulching than that of non-mulching. Dry rhizome weight per plant was increased, but that of per unit area was decreased at lower planting density.

• Korean Journal of Environmental Agriculture
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• v.25 no.3
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• pp.268-275
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• 2006

ALA (5-aminolevulinic acid) has been proposed as a tetrapyrrole-dependent photodynamic herbicide by the action of the protoporphyrinogen IX oxidase (Protox IX). A study was conducted to determine photodynamic herbicidal effect of ALA on seedling growth of rice (Oryza sativa L.) and barnyard grass (Echinochloa crus-galli Beauv. var. oryzicola Ohwi) under dry and wet conditions. ALA effect on early plant growth of rice and barnyardgrass was greatly concentration dependant, suggesting that it promotes plant growth at very low concentration and inhibits at high concentration. No significant difference in herbicidal activity of biologically and synthetically produced ALAs on plant lengths of test plants was observed ALA exhibited significant photodynamic activity regardless of PSDIP and its duration. Significant shoot growth inhibition by ALA soaking treatment exhibited apparently, indicating that ALA absorbed through root system was translocated into shoot part of plants. ALA reduced plant heights of rice and barnyardgrass seedlings by 6% and 27%, respectively, showing more tolerant to ALA in rice under wet condition. Leaf thickness was reduced markedly by ALA with increasing of ALA concentration, due to mainly membrane destruction and severe loss of turgidity in mesophyll cells, although the epidermal was little affected. It was observed that photodynamic herbicidal activity of ALA applied by pre-and post-emergence application exhibited differently on plant species, and that the activity of ALA against susceptible plants was highly correlated with growing condition.

• Weed & Turfgrass Science
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• v.2 no.2
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• pp.164-169
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• 2013

Alternatives to commercial chemical herbicide are currently being searched and tested due to the numerous adverse effects of commercially available herbicides to the environment. Barnyardgrass (Echinochloa crusgalli) is an important weed species around the world, especially in paddy rice fields. This study focuses on the favorable effects of mixing pyroligneous acids with commercial liquid herbicides. Seedlings were transplanted and grown under greenhouse conditions. The effect of treatment time or leaf-stage on herbicide-pyroligneous acid efficacies was checked, coupled with isolation and quantification of biochemical compounds. Results revealed that herbicide treatment at early post emergence (2~3 leaf stage) of Echnochloa crus-galli leads to effective control. Both liquid herbicides affected fatty acid, protein, and amino acid syntheses as reflected on their contents. The influence of wood vinegar (WV) or rice vinegar (RV) on these compounds was not thoroughly verified due to lack of information on the pyroligneous products. We observed that mixing WV or RV with BCB (bentazone + cyhalof-butyl) gives more favorable results than BUC (butachlor + clomazone), mixed with WV or RV. The result would indicate the potential of mixing pyroligneous acid in reducing herbicide application rate.

• Korean Journal of Plant Resources
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• v.9 no.1
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• pp.41-46
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• 1996

This study was carried out to gain the bagic information about agronomic characteristics and usage of Lactuca indica L. Cultivated at two different sowing dates at Green house of chungnam Rural Development administration from 1990 to 1995. Days to emergence of Lactuca at the delayed sowing of 30th May was promoted by four day than that of the early sowing of 15th Feburary. At the early sowing Ratio of emergency was appeared to be high than that of the delayed and Ratio of germination of Lactuca at $25^{\circ}C$ showed to be high as 89% especially, germination and growing and fresh weight were high at natural water soaking treatment than convential method. Length of leaf of Lactuca treated at Ga 50 and 100ppm was higher as 12 to 16cm than 36cm of check and fresh weight was also high as 21-56% than check in test of table guality fresh leaf of Lactuca was appered to be same favorite as perilla leaf, lettuce especially the usage of Lactuca grown about two to three weeks was appeared to be good.