• Journal of Bio-Environment Control
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• v.30 no.1
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• pp.10-18
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• 2021

Acclimatization after grafting and graft-take that in order to produce plug seedlings of high-quality are important plug seedling stage which not reduce the plug seedlings quality before shipment. Appropriate acclimatization environment can not only increase seedling quality before secondary growth period, but also effective in promoting the growth of plug seedlings. This study was conducted to determine the optimal the shading period and shading level for acclimatization of tomato and pepper grafted plug seedlings after graft-take. The tomato and pepper seedlings were used in this experiment, and after graft-take, a tunnel was installed on a bed in glasshouse of venlo type to started shading treatment. The shading levels were 35, 55, 75 and 95%, and the shading periods were 1 and 2 weeks, and non-treatment was set as the control. In the case of tomato grafted plug seedling, plant height, stem diameter, dry weight of root, leaf area were significantly higher at the shading period of 1 week and the shading level was 55%. In the case of pepper grafted plug seedling, plant height, stem diameter, and leaf area were the highest in the shading period of 2 weeks and the shading level was 35%. However, dry weight of root, compactness, and T/R ratio, which seedling quality indicators, were lower than in the shading period of 1 week and the shading level 55%. Therefore, considering the quality of seedlings, it is suggested that shading period of 1 week with shading level of 55% treatment can be suitable to produce high quality grafted plug seedlings of tomato and pepper.

• Korean Journal of Plant Resources
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• v.36 no.2
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• pp.181-190
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• 2023

Domestic hop (Humulus lupulus L.) production has been suspended since the early 1990s due to foreign imports, but interest in local production is rising due to the recent craft beer boom in Korea. This study was conducted focusing on the development of growth characteristics and propagation technology for 6 introduced hop cultivars as a basic study for domestic hop production and breeding program. In the hop growth survey conducted in 2021 and 2022, the 5-year-old plants after planting generally showed a tendency to increase the height of strobile setting, strobile size, number and weight of strobile per hill compared to the 4-year-old plants. As a result of the experiment with hop vine cuttings, the average rooting rate of all cultivars was as high as 88% even in only water treatment that were not added with Atonik (Atonik, Arysta, Japan), a rooting agent. There were differences between cultivars in rooting length and rooting rate according to the Atonik treatment method. When checking the survival rate of the rooted cuttings seedlings after transplanting into the soil, it was confirmed that the survival rate of the cuttings in the tissue culture room was significantly lower than that of the cuttings in the greenhouse. However, in transplanting step, cutting plants from culture room condition was strongly inhibited plant growth because of changing environment conditions. As a results of tissue culture, the thidiazuron (TDZ) 1 ㎎/L treatment in the media generated 6 to 9 shoots/explant, while the 6-benzylaminopurine (BAP) 1 ㎎/L treatment generated only 1 to 2 shoots/explant. Therefore, it is more effective to culture by adding TDZ rather than BAP. These results indicated that the development of technology to manage stably after transplanting of cutting or micropropagating plants into potting soil is important for mass propagation of hops.

• Korean journal of applied entomology
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• v.24 no.3 s.64
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• pp.123-127
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• 1985

Incidence of the Fusarium wilt caused by F. oxysporum f. sp. vasinfectum of sesame (var. Kwangsan) was remarkably influenced by seeding date and mean air temperature in the field of two or three year's continuous cropping with sesame in 1983 and 1985. Sesame were seeded on six different dates from April 20 to July 5. Air temperature was checked daily at the meteorological station near the experimental field. Low($16{\sim}20^{\circ}C$) and high temperature($20{\sim}25^{\circ}C$) periods were provisionally devided, based on every ten-day mean daily temperature during field experiment for last ten years, which corresponded to before and after June 15 in Jinju, Gyeong-nam. Infection rates were 83.7%, 68.2% and 59.4% in the plants grown for 55 days (seeding date: April 20), 40 days(May 5) and 25 days(May 20) under low temperature. On the other hand, infection rates were below 3% in those plots seeded during high temperature period. The longer the growth period exposed to low temperature, the higher was infection rates. It is interesting to note that 40 days old seedling or older are prone to severe infection compared to the younger ones, in higher temperature of $20{\sim}25^{\circ}C$. Therefore, seedlings in vegetative growth stage are less prone to infection than these in reproductive growth stage. The result showed that air temperature during sesame growth was one of the most important factor affecting the incidence of Fusarium wilt. This suggested that sesame crop, which is of tropical origin, has been predisposed to Fusarium wilt, when the plants were exposed to low temperature of $16{\sim}20^{\circ}C$.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.2
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• pp.105-110
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• 1994

Field experiment was carried out to obtain the basic information on the soil improvement with different improved methods on job's tears yield and soil properties in the newly-reclaimed land from 1985 to 1988. Job's tears yield, soil properties and annual changes of soil were investigated and analyzed. Soil bulk density and hardness of topsoil decreased from 1st year to 3rd year, but those increased in 4th year. Soil pH of topsoil had no differences in different soil depths and cultivated years. Average yield of job's tears in the integrated improvement plot was 2.16ton/ha. That was increased by 49% than the control plot. Crop yield was greatest in order of integrated improvement>subsoiling>phosphate>lime>compost>control plot. Correlation coefficients of job's tears yield with soil pH and organic matter content were higher significantly. Also those of subsoil were higher than topsoil. Ratios of annual changes of soil bulk density and hardness showed significant highly with job's tears yield. Also that soil pH was significant at 5 % level in the topsoil.

• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.1
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• pp.52-60
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• 1995

This experiment was carried out to determine the effect of nitrogen application level of cattle sluny(T1:150, T3:250, T53.50 kglha) and chemical fertilizer(T2:150, T4:250, T6:350 kg/ha) on the growth characteristics, dry matter yield and chemical soil property of Sorghum-Sudangrass hybrid [Sorghum bicolor L. Moench]. The results obtained are summarized as follows: Mean stem diameter was significantly increased by increasing nitrogen application level of cattle slurry and chemical fertilizer. Especially, T6 treatment was the highest as 11.1 mm, while T1 treatment w a the lowest as 0.3 mrn. According to the same level of nitrogen application, cattle slurry treaunent(T1, T3 and T5) were showed a lower mean stem hardness than chemical fertilizer treatment(T2, T4 and T6). Especially, T3 treatment was the softest at 0.7 kg/$cm^2$. The dead stubble and tiller number were increased by increasing nitrogen level of cattle slurry and chemical fertilizer(P

• Korean Journal of Environmental Agriculture
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• v.9 no.1
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• pp.53-59
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• 1990

Root zone environments in hydroponics are very important factors in crop growth, development and quality. In Korea, improvement of root zone temperature is required because of the continental climate. Therefore, this investigation was carried out to clarify the difference of root zone environments in different hydroponic systems under different climates. Tomato plants were grown in nutrient solutions at Seoul City University and Allen Cooper's. Hydroponic systems in this experiment were aeroponics, nutrient film technique(NFT), rockwool culture, sand culture and smoked rice hull culture(SRH). The decrease in temperature rapidly occured in sand culture while slowly in rockwool culture in low air temperature periods. The internal temperature of substrates of hydroponic bed were slightly changed in rockwool culture under high air temperature periods, while the duration of high temperature was longest in NFT. Electrical conductivity and pH of nutrient solution showed great changes in rockwool and aeroponics. Along the bed, the content of dissolved oxygen in nutrient solution had a tendency to decrease in NFT and DFT(Deep flow technique), while didn`t a change with aeroponics. Root activity measured by triphenyl tetrazolium chloride (TTC) was highest with aeroponics, followed by rockwool culture and NFT.

• Korean Journal of Environmental Agriculture
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• v.24 no.4
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• pp.398-403
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• 2005

To establish law-put fertilization technique and increase of fertilization efficiency during cultivation of plastic film mulching for plastic the improvement of soil properties, nutrition efficiency and yield by banded subsoil fertilization (BSF) using band spoty applicator was conducted at radish (Raphanus sativus L.) field in Honan Agricultural Research Institute from 1997 to 1998 for 2 years. These results were as follows. T-N, available $P_2O_5$ exchangeable Ca and K contents of soil were increased those of before experiment especially in BSF treatment. Also, the content of soil $NO_3-N$ was higher in BSF as fertilization amount is increasing than in CF (conventional fertilization). Uptake amounts of nitrogen fertilized were high in BSF during overall the growth period of plant and N utilization was high by $21.9{\sim}30.4%$ in BSF compared to in CF. The rate of fertilizer loss by rainfall was largely reduced, because all fertilizer applied was putted around the root zone. The total yields of fresh radish BSF treatments were more increased $13{\sim}37%$ than that of CF treatment.

• Research in Plant Disease
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• v.17 no.2
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• pp.142-147
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• 2011

In order to develop a environmentally friendly control protocol for managing tomato leaf mold disease in the field, we employed bacteria- and fungi-based commercially available microbial preparations. The field experiment was conducted from April to July in 2010. Average incidence rates tomato leaf mold caused by Fulvia fulva were 13.1% at the two plastic houses located in Jangsung, Jeonnam area. Initially 11 microbial preparations were tested for antifungal activity against F. fulva in vitro. Among them, 7 selected preparations showed to be inhibited the mycelial growth of the fungal pathogen over 50%. Four microbes suppressed disease incidence as much 50% under greenhouse condition. Eventually in the field two microbial products including Bacillus subtilis GB-0365 and B. subtilis KB-401 respectively were showed control value up to 71.8% for four times sprays from 20 days to 70 days after transplanting. Furthermore, the control value of three times spray program demonstrated 79.3%. Efficacy of the three and four spray programs was more effective than that of non-spray control treatment. Our results indicated that adjustment of application method of commercially available microbial preparation could be used to control a target plant disease as an effective and efficient crop protection system for organic farming.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.2
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• pp.95-101
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• 2006

This study was conducted to establish a low-input fertilization technique and increase of fertilization efficiency using the band spotty applicator(1999-2000) during the cultivation of mulching for chinese cabbage(Brassia campestris L.). The obtained results such as nitrogen efficiency, yield and soil improvement after cultivation of chinese cabbage were as follows. The content of $NO_3-N$ in soil increased in band spotty fertilization(BSF) by increasing application rate from the beginning stage to the middle stage. The content of total nitrogen increased but content of organic matter, available phosphate and exchangeable potassium decreased in comparison with the soil before experiment. Growth rate of Chinese cabbage increased in band spotty fertilization plot and uptake amount of nitrogen fertilized for chinese cabbage increased by increasing of the application rate. N use efficiency was higher by 5-21% in band spotty fertilization plot than in conventional fertilization(CF) plot. Yield of chinese cabbage increased by 16% in 70% band spotty fertilization plot and increased by 20% in 100% band spotty fertilization plot. It was found that 70% band spotty fertilization was more effective as fertilization method to reduce both environmental pollution and chemical nitrogen fertilizer in plastic film mulching cultivation.

• Korean Journal of Environmental Agriculture
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• v.15 no.3
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• pp.341-347
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• 1996

A green-house experiment was conducted to investigate the growth of Chinese cabbage, radish, and soybean and changes in soil chemical properties after application of 5 and 10mm of pH 2.7 simulated acid rain(SAR) followed by 0, 5, and 10mm of pH 6.0 normal water at the three-day intervals 20 times for Chinese cabbage and radish and 42 times for soybean. The results obtained are summarized as follows: 1. Visual damages by SAR were white-yellow leaf spots, dark brown or light green leaf color, and wrinkled leaf margins in all crops. The degree of visual damages was severer at 10mm than at 5mm SAR and it was reduced as the amounts of normal water increased after SAR application. 2. Chlorophyll content was higher at 10mm than at 5mm SAR application and increased as the amounts of normal water increased after SAR application in all crops. 3. Fresh weights of Chinese cabbage heads and radish roots and grain yield of soybean were higher at 10mm than at 5mm SAR, while they increased as the amounts of normal water increased at the same SAR level. 4. Changes in the mineral contents of plants were not consistent, while S content in radish and soybean increased as the amounts of SAR increased. 5. SAR lowered soil pH, while it increased soil N and S contents. Contents of soil organic matter, P, and exchangeable Ca, Mg, and K were not affected by the amounts of SAR.