• Korean Journal of Weed Science
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• v.14 no.2
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• pp.81-93
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• 1994

This study was conducted to characterize herbicidal activity of the new type diphenylether compounds inducing bleaching(whitening) in relation to their chemical structures and to find out the herbicidal action mechanism. Bleaching was highly appeared in the compounds which have short chain alkyl or allyl group of cabamoyl type in meta position of A ring and nitro group in para position of B ring, and KC6361 showed the highest efficacy among these derivatives. Rice was tolerant to KC6361 at 2.0kg/ha. The applications of this compound at 0.25~1.0kg/ha provided acceptable control of the various weeds including large crabgrass, barnyardgrass, pigweed and so on. In the dark condition, KC6361 decreased carotenoid contents but increased chlorophyll in etiolated cucumber cotyledon. By the increase of light intensity, the carotenoid biosynthesis was more inhibited than the chlorophyll biosynthesis. The incorporation of $C^{14}$-acetate into lipid was slightly inhibited. Both KC6361 and norflurazon stimulated growth of dwarf rice(cv. Daneunbanju). These results suggest that both KC6361 and norflurazon may have the same action sites. To confirm this hypothesis, the changes of carotenoid intermediates in cucumber cotyledon and barnyardgrass leaf treated with KC6361 were investigated. Phytoene and phytofluene were increased but ${\beta}$-carotene was decreased, indicating that KC6361 inhibited phytoene and/or phytofluene dehydrogenase like norflurazon.

• Journal of Bio-Environment Control
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• v.12 no.4
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• pp.259-265
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• 2003

The physiological changes and antioxidant enzyme activities of plug seedlings irradiated with 4 kJ${\cdot}m^{-2}{\cdot}d^{-1}$ UV-B or sprayed growth inhibitors of 50 ${\cdot}L^{-1}$ diniconazole and 500 mg${\cdot}L^{-1}$ hexaconazole for retarding the overgrowth of cucumber, tomato and hot pepper seedlings in summer season were investigated. Photosynthetic rate just after UV-B irradiation was significantly low but recovered to the level of non-treated seedlings 10 days after IV-B irradiation. And photosynthetic rate of chemical-sprayed seedlings was slightly lower in tomatoes but not different in cucumbers and peppers, compared with non-treated seedlings. Cholrophyll contens in the leaves showed no difference among treatments. Anthocyanin contents in the leaves of UV-B-irradiated seedlings were higher and no difference inchmical-sprayed seedlings, compared with non-treated seedlings. the activites of SOD(superoside dismutase), CAT )catalase), and POD(perosidase) of UV-B-irradated seedlings were higher thatn those of the non-irradiated seedlings just after UV-B irradiation. However. 10 days after UV-B irradiation, the activities were decreased to half of the value just after UV-B irradiation Whereasd the activies of chemical-sprayed seedlings were slightly higher than those of non-treated ones but lower than those of UV-B-irradiated one.

• Food Science and Preservation
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• v.24 no.2
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• pp.159-167
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• 2017

This study was investigated the effects of maintaining the freshness and stabilization of supply and demand for lettuce (Lactuca sativa L.) by packaging methods in summer. Post-harvest lettuces were packaged by corrugated box, polypropylene (P) box, and individual wrapping using polyvinyl chloride (PVC) film. Then, the lettuce samples were stored at $2^{\circ}C$ and evaluated the change of quality during storage. The lettuces wrapped individually with PVC film had lower weight loss rate, color change, and browning index compared to lettuces packaged by corrugated box and P box. The SPAD value and hardness were higher in lettuces wrapped individually with PVC film than other packaging methods. The lettuces wrapped individually with PVC film were showed the highest total phenolic contents and DPPH radical scavenging activity, but there were no significantly differences by packaging methods. The lettuces packaged by corrugated box were showed the inside browning after 14 days. However, the lettuces wrapped individually with PVC film were showed the best appearance. Therefore, the packaging method of wrapped individually with PVC film were effective in maintaining the freshness during 21 days and helpful for the stabilization of supply and demand for lettuce in summer.

• Korean Journal of Environmental Agriculture
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• v.18 no.4
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• pp.327-331
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• 1999

The purpose of this study was to find out the effects of slow-released nitrogen fertilizer (SRF) on the growth and yield of Chinese cabbage. The SRF used in this study was prepared by embedding urea into a waste paper slum. The underwater dissolution rate of SRF was very rapid during the first 12 hours and 60.4% of the embedded nitrogen was released after 72 hours. The SRF and urea was applied as nitrogen source and growth. yield, yield components, nitrogen uptake of Chinese cabbage were investigated a pot experiment. Maximum leaf length of Chinese cabbage was not different between SRF and urea treatments. Length and wish of head, number of leaf per head and fresh weight of Chinese cabbage were higher in SRF treatment than those in urea treatment, but the differences were not statistically significant. Comparing to the urea treatment, nitrogen content and nitrogen uptake efficiency of Chinese cabbage were significantly higher in SRF treatment. After the experiment, total soil nitrogen contents were not different between the SRF and urea treatments.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.552-560
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• 2010

$GA_{4+7}$+BA, a plant growth regulator for induction of feathering in young apple tree and increasing fruit size, was applied by various methods on 'Gala'/M.9 apple trees in high density orchard for 4 years to investigate its effect on fruit and shoot growth. $GA_{4+7}$+BA($80-300mg{\cdot}L^{-1}$) increased fruit length, fruit weight, and L/D ratio regardless of application methods, but it did not affect soluble solid content, acidity, leaf area, and chlorophyll. Seed number was not affected by $GA_{4+7}$+BA application, however, more immature seeds was observed in treated 'Gala' fruit. Shoot growth was increased when spraying $GA_{4+7}$+BA at tree crown but not affected when spraying at fruit directly. More significant fruit growth was observed when $GA_{4+7}$+BA was applied on the fruits between late of May and early of June when fruit cell division ended; however, high concentration of $GA_{4+7}$+BA resulted in lower fruit storability because of lower firmness. Hence, more attention should be paid when applying high concentration of $GA_{4+7}$+BA to small sized fruit cultivars like 'Gala'.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.3
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• pp.45-49
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• 2020

The aims of this study is to land improvement effect of sewage sludge dry fuel mixture. The mixing ratio of sewage sludge and dry fuel was mixed at a weight ratio of 1:1 to make a mixture, experimental designone was designed as one control (0 %) site and three test groups that each mixture of 10 %, 20 %, 30 % was added. Comparison of yield after cultivation of Kenaf 90days, in the 10 % test group the length of the stem increased by 73 % compared to control site and 20 % test group the leaf yield increased by 227 % compared to control site. It is judged that the growth rating the blooming of 30 % test group is faster than and the chlorophyll content is the highest(71.6SPAD) that of another control. In conclusion, the addition of dry fuel mixtures is effective in improving overall soil quality for plants to live.

• Asian Journal of Turfgrass Science
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• v.24 no.2
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• pp.138-144
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• 2010

This study was conducted to investigate the effect of Lactobacillus sp. and Saccharomyces sp. on turf quality, shoot and root growth of creeping betgrass in golf course by measuring turf color index, chlorophyll content, dry weight of shoot and root, T/R ratio and root length. Fertilizer treatment was designed as follows; nonfertilizer (NF), control (CF; compound fertilizer), microorganism medium(MO; CF+MO)), microorganism medium contained Fe(MO-Fe; CF+MO-Fe) and microorganisum medium contained S (MO-S; CF+MO-S). Soil properties investigated after experiment was scarcely affected by applied fertilizers in root zone of creeping bentgrass. The turf color index and chlorophyll index of MO, MO-Fe, MO-S treatment were higher than those of NF, and similar to those of CF. The turfgrass root in MO and MO-Fe treatment was longer than others. The dry weight of shoot in MO and MO-S was higher than CF and that of root in MO and MO-Fe, and dry weight of MO was increased than that of NF and CF, by 26% and 6%, respectively. AS compared with NF, T/R ratio of CF, MO, MO-Fe and MO-S was increased, and MO and MO-Fe was similar to CF, MO-S higher. Nutrient content in CF, MO, MO-Fe and MO-S was contained more than in NF, and it was higher in shoot. These was suggested that application of MO induced the development of quality and growth of creeping bentgrass by assisting root growth and nutrients uptake.

• Korean Journal of Plant Resources
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• v.24 no.5
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• pp.613-621
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• 2011

Plastic house and laboratory experiments were conducted to determine the effects of substrate components and shade degrees on plant growth and physiologically-active substance content and antioxidant activity of Panax ginseng. No significant difference in growth characteristics among substrates was observed. However, shade treatment also significantly reduced leaf area, chlorophyll content, root length, and shoot and root fresh weight (P<0.05) with increasing of the degree. Total phenolics level [mg ferulic acid equivalents (FAE) $kg^{-1}$ DW] was higher in root parts (25.8 to 28.4 mg $kg^{-1}$) than shoot parts (20.7 to 23.8 mg $kg^{-1}$) of Panax ginseng, and with shade (23.7 to 28.4 mg $kg^{-1}$) than without shade (20.7 to 25.8 mg $kg^{-1}$). However, total flavonoids [mg naringin equivalents $kg^{-1}$ DW] was more detected in the shoot part (17.4 to 26.8 mg $kg^{-1}$) than in the root part (6.7 to 7.0 mg $kg^{-1}$) of Panax ginseng. Methanol extracts from the Panax ginseng plants dose-dependently increased DPPH free radical scavenging activity as a antioxidant potential, and the activity was higher in shoot parts (31.1 to 36.5%) than in root parts (24.9 to 28.7%), and without shade than with shade. In conclusion, shade affects plant growth as well as physiological activity of Panax ginseng under plastic house condition.

• Journal of Korean Society of Forest Science
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• v.109 no.1
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• pp.50-61
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• 2020

Street trees are very important to urban environments as they can alleviate air pollution. However, when ozone is absorbed through the stomata, it can induce the formation of free radicals inside the tree, negatively affecting the vegetation. The present study investigated the Air Pollution Tolerance Index (APTI) of four major street tree species: Prunus yedoensis, Zelkova serrata, Chionanthus retusus, and Pinus densiflora. Two-year-old seedlings were placed in a phytotron and fumigated with 100 nL·L^-1 (ppb) ozone for 4 weeks, following which the ascorbic acid contents, chlorophyll contents, leaf pHs, and relative water contents were measured. There was no significant difference in the APTI of Prunus yedoensis and Zelkova serrata between the ozone and control treatments. By contrast, the ozone treatment caused the APTI of Chionanthus retusus to increase and that of Pinus densiflora to decrease compared with the respective controls. These results suggest that the APTI of these tree species exhibit very different responses to ozone. Therefore, more detailed research should be conducted on a range of species in the future.

• Horticultural Science & Technology
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• v.30 no.5
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• pp.519-526
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• 2012

Anaerobic treated green teas were sealed with aluminum pack and stored for 12 months at three different temperatures such as 25, 4, or $-10^{\circ}C$. Anaerobic green teas were evaluated with respect to physiochemical properties and physiological functions. The longer anaerobic green teas were stored, their total nitrogen, tannins, or chlorophyll contents were reduced. Especially, the lower storage temperature of green tea resulted in less loss of physiochemical contents in green tea. Since green teas stored at $-10^{\circ}C$ exhibited less loss of physiochemical contents, compared to green teas stored at 25 or $4^{\circ}C$. The qualities of green teas stored at $-10^{\circ}C$ for 12 months were similar with those of teas stored at $4^{\circ}C$ for 8 months or stored at $25^{\circ}C$ for 4 months. Since 'a' value (green color) of green tea was considered as an important criteria to evaluate the tea quality. Anaerobic teas stored for 12 months were monitored their 'a' color values with -12.40 (fresh one), -10.54 ($-10^{\circ}C$), -9.77 ($4^{\circ}C$), and -9.06 ($25^{\circ}C$). Sensory evaluation results showed that anaerobic teas at $-10^{\circ}C$ were more favored than those at or 4 or $25^{\circ}C$. In conclusion, optimum storage temperature for anaerobic green teas should be $-10^{\circ}C$.