• Korean Journal of Medicinal Crop Science
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• v.4 no.3
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• pp.241-246
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• 1996

This Experiment was conducted to know effect of cutting times and nitrogen split application rates on shoot and root-related characters of Atractylodes japonica. The cutting time was forced on none, once and twice along with three levels of nitrogen split application, all basic 50 -30 -20% and 40 -30 -30%. The plant height declined with increased cutting time and dry matter weight was increased with nitrogen split application under none and once cutting. Average yield of cutted shoot as edible wild plant was 257kg/10a at once cutting condition, but twice cutting condition was little and unfavorable to use edible wild plant because shoot was coarse. Yield 0 dry rhizome was the highest at once shoot cutting und­er 50 -30 -20% nitrogen split application by 471kg/10a.Especially, culture of Atractylodes japonka needed once shoot cutting one the 10th-30th of May.

• Korean Journal of Environmental Biology
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• v.17 no.4
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• pp.459-465
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• 1999

This work focused on the effects of the timing and the frequency of shoot cutting to maximize the productivity and the nutrient removal of three emergent macrophytes, Phragmites communis, Zizania latifolia and Typha angustifolia in natural wetlands. Shoot cutting significantly enhanced biomass production and resulted in more nitrogen and phosphorus removal from water in these three experimental species, compared to those of control. However, the frequency and the timing of shoot cutting, and the enhancement ratio were different among three species. For Phragmites stands, the highest productivity was 1.9 times of control in June treatment of the first year experiment, while 1.3 times in May treatment of the second year experiment. Zizania and Typha stands were both 1.2 times of control in August treatment and June and August treatment. Calculating the total annual removal rate of nitrogen and phosphorus based on the highest productivities among treatments, in Phragmites stands, 2.0 times of nitrogen and 1.8 times of phosphorus were removed in the first year, and both 1.4 times in the second year experiment. Likewise, for nitrogen and phosphorus; 2.4 and L.8 times in Zizania stands, and 1.8 and 1.9 times in Typha stands were removed. Overall, these results suggested that cutting treatment of shoots be effective. Thus, shoot cutting of two times during a growing season were recommended to maximize the effects: that is, in May or June, and October for Phragmites stands, and in August and October fur Zizania and Typha stands.

• Journal of The Korean Society of Grassland and Forage Science
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• v.7 no.3
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• pp.128-134
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• 1987

This experiment was conducted to evaluate the effects of cutting in field and solution culture. Periodical samplings of alfalfa in cutting and uncutting plots were taken to measure nodule development and nodule activity. Regrowth of plant and nodule development after shoot cutting by different heights and nodule removal at different levels were investigated in solution culture of alfalfa plant. 1. Nodule weight in the field was reduced 30% after the first cutting and 25% after the second cutting, but during the following 30 days after second cutting, there was no significant difference between cutting and uncutting plots. 2. Specific nodule activities of cutting plots at the beginning of June and at the beginning of September were 80% and loo%, higher than those of uncutting plots respectively. Total nodule activities of cutting plots in late August and early September were 40% higher than those of uncutting plot. The decrease of nodule activity can be prevented by cutting at flowering stage. 3. The decrease of nodules in solution culture when 50% of the shoot was cut, was as much as that when shoot was not cut or flower buds were removered. But when 90% of the shoot was cut, the number of the nodules were decreased more remarkably than the above treatments. New nodules, when 90% of the shoot was cut, were reformed slowly and did not grow fully until 15 days after cutting.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.1
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• pp.41-48
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• 1992

This experiment was carrid out to determine the effect of cutting height and nitrogen level on dead stubble, tiller and branch new shoot dry matter yield and total dry matter of sorghum-sudangrass hybrid{Sorghum bicolor (L.) Moench}.The main treatment was four cutting height(5cm, IOcm, 15cm, 20cm), and the sub treatment was three nitrogen level(l50kg, 250kg, 350kglha).The experiment was performed at the Collage of Natural Science of Kon-Kuk University at Chungju in 1988. 1. Plant length tends to increase in the high cutting height and high N level. Especially, the difference of plant height was significant in warm season. 2. The number of dead stubble after cutting was significantly(P

• Journal of Korean Society on Water Environment
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• v.25 no.2
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• pp.221-226
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• 2009

We investigated the most effective cutting interval for underwater nutrient removal through cut off the emergent part of hydrophytes at artificial vegetation island (AVR) which was installed for the purpose of water quality improvement in Lake Paldang. We divided the planting area of Phragmites japonica into three parts according to the cutting intervals. The shoot height and relative growth rate of P. japonica, nutrient contents and biomass of cut off P. japonica were measured at each cutting interval. The amount of nutrients which were removed through cut off at each cutting interval was calculated. P. japonica showed full growth, 80% and 60% of full growth before first cut off at three-months, two-months and one-month cutting interval condition respectively. Three-month cutting interval condition showed the largest biomass of cut off P. japonica and one-month cutting interval condition showed the least. However the cut off P. japonica showed the highest content of nutrients at one-month cutting interval condition and the least at three-month cutting interval condition. The amount of phosphorus and nitrogen removal at two-month cutting off condition is the largest among three cutting interval conditions indicating that cut off the emergent part of P. japonica every two months is the most effective to remove the nutrients from water at AVR in eutrophic lakes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.3
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• pp.298-305
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• 1984

The competitive relationship between orchardgrass (Dactylis glomerata L.) and ladino clover (Trifolium repens L.) was studied under aerial and soil partitions and N, P fertilizer combinations. Orchardgrass and ladino clover were grown in field with one of non competition, shoot competition only, root competition only, full competition and competition between same species. Under basal application of K fertilizer N and P were applied in treatment combinations of blank, N only (l5kg/10a), P only (l5kg/10a), and both NP at planting and each cutting. The forage yield in mixture was between yield of pure orchard grass stand and the 'expected yield', which was a mean of both pure stands. The forage yield in pure ladino was the lowest. During the experiment there was a progressive decline in clover yield either pure stand or mixture. Since orchardgrass was 'over-compensated' to low-yielding clover, the yield of mixture was more than non competition. Orchard grass was more competitive than ladino clover as seasons advanced. The aggressivity of orchardgrass was higher in root competition than in shoot competition comparing to clover. Nitrogen fertilizer increased orchardgrass yield, while phosphate did ladino clover yield and root weight of both species. But the additional effect of P to N was not significant in dry weight and LAI.

• Korean Journal of Weed Science
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• v.13 no.1
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• pp.44-54
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• 1993

This experiment was conducted to understand the environmental factors affecting growth and tuber formation such as temperature, day length, tight intensity, water condition and cutting time of Eleocharis kuroguwai Ohwi. Plant height, shoot number and dry weight of E. kuroguwai were higher at high temperature, 25/$25^{\circ}C$ (day/night), while nitrogen content was higher at low temperature, 20/$15^{\circ}C$. Plant height was more affected by water temperature, while shoot number and dry weight were more affected by air temperature. Contents and absorption of nitrogen, phosphorus, and potassium in top parts of E. kuroguwai were higher under greater difference between air and water temperatures, i.e., 18/$28^{\circ}C$ and 28/$18^{\circ}C$. The number and weight of tubers were increased under greater difference between air and water temperatures, i.e, 18/$28^{\circ}C$ and 28/$18^{\circ}C$, while they were inhibited at low or high air/water temperatures (18/$18^{\circ}C$ or 28/$28^{\circ}C$). Tubers of E. kuroguwai were formed at 8-or 12-hour day length, however, no tuber was formed at l6-hour day length. Photoinductive period for tuber initiation of E. kuroguwai was between 30 and 45 days after emergence, and the induction period of short-day treatment was less than 10 days. Tuber number and weight were reduced by shading due to inhibition of the growth of top and underground parts. Number of days from planting to tuber initiation was shortned as planting time was delayed and plant height, dry weight, and tuber number were also reduced by delayed planting. Tuber number at l0 to 15cm water depth was decreased 63 to 75% as compared with 1 to 5cm water depth. Tuber number and dry weight were not affected by the size of tubers at planting. Due to the reduced growth of top and underground parts, tuber number and dry weight of E. kuroguwai were decreased by delayed shoot cutting. The critical cutting time to inhibit the growth of E. kuroguwai was about 70 days after emergence.

• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.437-450
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• 2013

Miscanthus sacchariflorus var. No. 1 has been newly developed in Korea. This study was conducted to assess the feed value of M. sacchariflorus var. No. 1 at different growth and harvesting time. Total 3 different miscanthus - 1y4m (first shoot and harvested at 4 month), 2y4m (second shoot and harvested at 4 month) and 2y8m (second shoot and harvested at 8 month). Two experiments were carried out, In vitro rumen simulated fermentation and In situ dry matter digestibility (DMD). Ruminal pH at in vitro fermentation were higher in M. sacchariflorus var. No. 1 treatments compared to the rice straw (RS). In volatile fatty acid production, 1y4m resulted in higher acetate production than the other M. sacchariflorus var. No. 1 at higher maturity stages. Significant differences among treatments were observed in propionate and total volatile fatty acid (VFA) productions at 9, 24 and 48 h of incubation times. Higher ammonia nitrogen productions were found as increased maturity of M. sacchariflorus var. No. 1. At In situ experiment, high DMD was detected in the order of RS (60.51%) > 1y4m (57.65%) > 2y4m (57.63%) > 2y8m (46.28%). The results from this study indicate that young and early harvested M. sacchariflorus var. No. 1 are able to improve its nutrient values in the ruminant animal.