• Korean Journal of Environment and Ecology
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• v.21 no.6
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• pp.544-553
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• 2007

This study is focused on the cultivation of seedlings and cuttings of roundleaf chastetree(Vitex rotundifolia L. f.) according to the sorts of soil and fertilization methods. The results are summarized as follows: When roundleaf chastetree seedlings(aged 1-0) and cuttings(aged 1-0) were cultivated in three different kinds of soil- sand, granite soil, and yellow silt- without any fertilization, 70% of the seedlings survived in sand and granite soil, and 35% did in yellow silt; 90% of the cuttings survived in granite soil and 80% did in sand and yellow silt. The general growth of both seedlings and cuttings was good in granite soil, and sand but relatively inferior in yellow silt. Seedlings showed good stem growth while cuttings had fine root growth. In case of cultivation of seedlings with different kinds and quantities of fertilizer adjusted and with granite soil as basic soil, seedlings and cuttings survived in the experimental section where only the organic fertilizer was used as basic fertilization; in contrast, seedlings grown in the experimental section were all dead where both inorganic and liquefied fertilizer were used. Cuttings showed considerably higher survival rates than seedlings at the experimental fertilization section; particularly, the survival rate of cuttings was twice as much as that of seedlings at the experimental section with low fertilization. This study results revealed that cuttings are desirable than seedlings in general rootage, growth, adaptability to soil, and cuttings have lower demand for soil fertility in time of growing roundleaf chastetree saplings.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.217-222
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• 2011

Professional turfgrass applicators have reduced or eliminated phosphorus from their fertilization programs based on the assumption that soil phosphorus levels are supplying adequate amounts of phosphorus to the turfgrass. The previous researchers found that there were no P effects for turfgrass growth especially for mature turf. No effects may result from high P level in heavy thatch layer. The research was conducted for one year to investigate the effects of phosphorus fertilization programs on turfgrass performance, and monitor soil and plant tissue nutrient levels to determine the impact of the programs on a newly seeded Kentucky bluegrass. The nitrogen treatments were 20, 30 and $40g\;m^{-2}\;yr^{-1}$. The low, medium, and high nitrogen treatments were applied over 2, 4 and 6 applications, respectively. Nitrogen was applied using a formulation containing 30% of slow and 70% of fast release nitrogen sources that are representative of typical home lawn fertilizers. The phosphorus treatments were 0, 10 and $20g\;m^{-2}\;yr^{-1}$. Phosphorus was applied according to the application schedule for the nitrogen treatments. Kentucky bluegrass was seeded in May, 2010. The thickness of thatch layer was less than 1 cm and the first treatment was applied to Kentucky bluegrass in April, 2011. The low N rate treatment had acceptable color and quality ratings without high clipping yields. The high N rate treatment consistently had the highest color and quality ratings but also had very high clipping yields in comparison to the low and medium N rate treatments. Although there are significant differences in tissue P, Overall, there was no effect of phosphorus on color, quality, or clipping weights.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.4
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• pp.271-280
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• 1994

The aim of this experiment was to investigate the effects of fertilizing mineral nitrogen on dry matter yield of Reed canarygrass and also to estimate proper levels of fertilizing nitrogen when uncultivated rice paddy rapidly increased these days, was used for the production if Reed canarygrass. \ulcornerhe results are as follows. 1. Relative dry matter according to cutting frequency was appeared the highest at the 2nd cut for 3 and 4 cutting frequencies, and the 3rd cut for 5 cutting frequency. Those were 43.1, 34.0 and 34.1 % respectively. 2. When using only phosphrous and potassium, the average dry matter per year and ha was between 9.0 and 12.0 tons(3, 4 and 5 cutting frequency) and the highest dry matter was shown at 5 cutting frequency. 3. In accordance to the increase in the fertilization of nitorgen, the yield of dry matter was increased and, when 30 kg/ha/cut of mineral nitrogen was added, the biggest increase rate per added nitrogen for dry matter yield per year compared to that of no fe~tilization of nitrogen was recorded and it was 2.7, 3.3, and 3.4 tons/ ha for 3, 4 and 5 cutting frequencies respectively. 4. The efficiencies of mineral nitrogen on dry matter yield(DM kg/N kg) were the highest when 30kg nitrogen was applied particularly in 3, 4 and 5 cutting frequencies(29.7, 27.2, 22.8 DM kg/N kg). It recorded the highest of all the treatments. The efficiency was actually decreased in higher application of mineral nitrogen. The total nitrogen yield efficiency was the highest in 30kg(0.45kg and 0.48kg at 4 and 5 cutting frequency) and 60kg fertilization/ha/cut (0.46kg at 3 cuting frequency) and the decreased efficiencies appeared at fertilization of higher nitrogen. 5. Economical borden of mineral nitrogen fertilization were between 199.2 and 243.3kglha at 3 cutting frequency, between 253.4 and 295.9kg at 4 cutting frequency and between 302.2 and 361.3kg at 5 cutting frequency. 6. Under the condition of this experiment, the cutting frequency leading the potential production at maximum was 3 cutting frequency. At 3 cutting frequency, the efficiency of nitrogen utilization was higher and 15 or 16 tons of dry matter was obtained which is a level of economical border at fertilization between 200 and 240kglha. It wrs possible to obtain the maximal dry matter yield(l7 tonslha) at fertilization of lower level than 400kgl ha.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.28-35
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• 2001

To investigate the effects of nitrogen fertilization and thinning on growth and nutrition of current-year needle and twigs in Pinus koraiensis we treated two clone banks with three levels of nitrogen fertilizer in Yongin and Chuncheon, and also thinned two plantations with three intensities in Yangpyeong. The fertilization and thinning effects greatly varied depending on study sites and stand ages. However, dry weights of needle and twig increased following low nitrogen fertilization in older stands. Moderate thinning increased dry weight and nitrogen concentration of twigs in the 12-year-old stand.

• Journal of The Korean Society of Grassland and Forage Science
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• v.7 no.1
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• pp.25-30
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• 1987

There are differences in opinion as to whether nitrogen fertilizer should be used when establishing alfalfa (Medicago sativa L.). Various reports show that under a hot environment, rhizobia (Rhizobium meliloti) are not as effective in fixing atmospheric nitrogen as they are under moderate temperatures. It is also believed that the addition of nitrogen fertilizer inhibits nodulation of alfalfa seedlings. A replicated experiment was conducted under controlled environmental conditions at the University of Nevada-Reno, Reno, Nevada, USA, to determine the effects of nitrogen application on seedling growth and nodulation of alfalfa grown in a hot environment. Sterile sand was used as the growing media to which a complete nutrient solution minus nitrogen was applied volumetrically to each pot daily. In addition, half of the pots received NH4-$NO_3$, at the rate of 11.2 kg per ha at seeding and at two and four weeks after planting giving a total nitrogen application rate of 33.6 kg per ha during the seven-week experimental period. Rhizobia inoculant (R-12) consisted of a mixture of strains 171-15a, 1682c and 80 PI 265 of (Rhizobium meliloti). Inoculant was applied to the seeds prior to planting and to the sand media at two and four weeks after seeding. Twenty seeds were planted in pots 14.0 cm in diameter and 11.5 cm deep. Plants were thinned to ten plants per pot after emergence and were grown in a controlled environment chamber with a 16-hour light period. Soil temperature at 6 cm depth ranged from 17.4^{\circ}C.$ to 31.1^{\circ}C.$ and had a daily mean of 26.5^{\circ}C.$. Plants were harvested at weekly intervals for seven weeks. Root, shoot and total length, dry weight, volume and number of nodules per plant were determined. Root, shoot, and total length were greater in seedlings grown in soil where nigrogen was applied than that grown in soil to which no nitrogen was applied. The average size of the seedlings as determined by volume and weight was more than two times greater where plants were fertilized with nitrogen. Nodule number per seedling was also greater when nitrogen was applied compared to those which received no nitrogen. The differences were greater as the plants became older. The rhizobia did not fix enough nitrogen for adequate growth of seedlings. This is probably due to high temperature growing conditions that caused the rhizobia to become relatively ineffective as compared to cooler growing conditions. Data suggests it would be desirable to apply nitrogen at seeding when alfalfa is established under hot conditions that occur in mid- or late summer.

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.3
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• pp.151-156
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• 1986

There are differences in recommendations in the USA as to whether nitrogen fertilizer should be applied when establishing alfalfa (Medicago sativa L). The reason for not applying nitrogen is because some researchers found the addition of nitrogen reduced nodulation of alfalfa plants. A replicated experiment was conducted under controlled environmental conditions at the University of Nevada-Reno, Reno, Nevada, USA, to determine the effects of nitrogen application on seedling growth and nodulation of alfalfa when grown in a cool environment. A sterile sand was used in the growing media to which a complete nutrient solution minus nitrogen was applied volumetrically to each pot daily. Half of the pots received $NH_4NO_3$, at the rate of 11.2 kg/ha, at seeding and two and four weeks after planting, giving a total nitrogen application rate of 33.6 kg/ha. Rhizobia inoculant (R-12) consisted of a mixture of strains 171-15a. 1682c and 80 PI 265 of Rhizobium meliloti. Inoculant was applied to the seeds prior to planting and to the sand media at two and four weeks after seeding. Twenty seeds were planted in pots 14.0 cm in diameter and 11.5 cm deep. Seedlings were thinned after emergence to ten plants per pot. They were grown in a controlled environment chamber with a 16-hour light period. Soil temperatures at 6 cm depth ranged from $5.7^{\circ}C\;to\;21.5^{\circ}C$ and had a daily mean of $16.2^{\circ}C$ Plants were harvested at weekly intervals for seven weeks at which time root, shoot and total length, dry weight, volume and number of nodules per plant were determined. Root, shoot and total length were not affected by nitrogen fertilizer. However, application of nitrogen increased the size of the seedlings as determined by dry weight and volume when compared to plants which were not fertilized. This indicates that rhizobia did not fix enough atmospheric nitrogen to promote good growth. Nitrogen application resulted in significantly more nodules per plant. The effect of nitrogen fertilizer became more apparent as the plant became older. Results of this experiment show there are benefits from applying nitrogen at a low rate when establishing alfalfa under a cool environment.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.3
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• pp.282-287
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• 1996

This study was conducted to identify the parameter better representing the nitrogen supply capacity of soils for the vegetable crops growing in vinylhouse. All the parameters showed significant positive correlation with the yield of chinese cabbage. The correlation coefficients were in the order of $NO{_3}^--N+NH{_4}^+-N(2M\;KCl)$ > $NO{_3}^--N(2M\;KCl)$ > OM > T-N > 0.01M $NaHCO_3$ > 0.01M $CaCl_2$ > $NH{_4}^+-N(2M\;KCl)$ > 6N HCl. Between the soil N and N absorbed by plant, the correlation coefficients were in the order of $NO{_3}^--N+NH{_4}^+-N(2M\;KCl)$ > $NO{_3}^--N(2M\;KCl)$ > 0.01M $NaHCO_3$ > $NH{_4}^+-N(2M\;KCl)$ > 0.01M $CaCl_2$ > OM > T-N > 6N HCl. The results of this study suggest that 2M KCl extractable inorganic N. 2M KCl extractable $NO{_3}^--N$ are recommendable parameters for the estimation of N supply capacity of the vinylhouse soils. The sum of soil $NO{_3}^--N$ and fertilizer nitrogen showed highly significant positive correlation with the yields of chinese cabbage and nitrogen absorbed by the plant, while negative correlation with the nitrogen use efficiency.

• Korean Journal of Soil Science and Fertilizer
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• v.5 no.1
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• pp.1-8
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• 1972

In order to expect the effect of silica with large quantity application of current Fused calcium-magnesium phosphate on the paddy rice, there are difficulties of excess phosphorus application because of the high content of phosphate in this fertilizer. This experiment was discussed on the effect of posphate and silica absorbed by rice plant from the low concentrated fused calcium-magnesium phosphate which was fused with mixture of rock phosphate, chemical calcium oxide, magnesium oxide and silicate oxide in the furnace using coke, 1. The fusion material contained 8.9% of citric acid soluble $P_2O_5$ and 33% of soluble $SiO_2$. 2. The rice yields were increased with high significance accompanying the application levels of fused material amounts. 3. No. of grains per head, weight of 1,000 grains and percent of filled grain were caused to increase the productivity of rice plant on account of the high content of silica in straws absorbed from fusion material. The treatment of 300 kg/10a. was the highest yield among the levels of fusion material. 4. At the growing periods of rice plant, amount of absorbed phosphate was higher in the small amount treatment of fusion material until the formation period of young head, and was highest in the treatment of 300 kg/10a. leval among them but slightly desreased at 500 kg/10a. level at the harvest. Amount of absorbed silica was the same trend with phosphorus at the begining of growth period but increased rapidly from the formation period of young head to harvest in the large quantity application levels. 5. Much amount of nutrients were residued in the soil after experiment pacing with application levels. 6. The effect of silica and phosphate on rice plant can be expected with fusion material but it is necessary to decrease the phosphate content on account of the large residue of phosphate in the soil after experiment.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.591-597
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• 2015

We determined the total C and N stocks in trees and soils after 1 year of fertilization in an experimental orchard with 16-year-old 'Niitaka' pear (Pyrus pyrifolia Nakai cv. Niitaka) trees planted at $5.0m{\times}3.0m$ spacing on a Tatura trellis system. Pear trees were fertilized at the rate of 200 kg N, 130 kg P and $180kg\;K\;ha^{-1}$. At the sampling time (August 2013), trees were uprooted, separated into six fractions [trunk, main branches, lateral branches (including shoots), leaves, fruit, and roots] and analyzed for their total C and N concentrations and dry masses. Soil samples were collected from 0 to 0.6 m in 0.1 m intervals at 0.5 m from the trunk, air-dried, passed through a 2-mm sieve, and analyzed for total C and N concentrations. Undisturbed soil core samples were also taken to determine the bulk density. Dry mass per tree was 5.6 kg for trunk, 12.0 kg f or m ain branches, 15.7 kg for lateral branches, 5.7 kg for leaves, 9.8 kg for fruits, and 10.5 kg for roots. Total amounts of C and N per tree were respectively 2.6 and 0.02 kg for trunk, 5.5 and 0.04 kg for main branches, 7.2 and 0.07 kg for lateral branches, 2.6 and 0.11 kg for leaves, 4.0 and 0.03 kg for fruit, and 4.8 and 0.05 kg for roots. Carbon and N stocks stored in the soil per hectare were 155.7 and 14.0 Mg, respectively, while those contained in pear trees were 17.8 and $0.2Mg{\cdot}ha^{-1}$ based on a tree density of 667 trees/ha. Overall, C and N stocks per hectare stored in the pear orchard were 173.6 and 14.2 Mg, respectively. Compared with results obtained in 2012, the amounts of C stocks have increased by $17.7Mg{\cdot}ha^{-1}$, while those of N stocks remained virtually unchanged ($0.66Mg{\cdot}ha^{-1}$).

• Applied Biological Chemistry
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• v.22 no.3
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• pp.181-189
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• 1979

In order to establish fertilizing technique for the increase of grain yield and its stability, the total absorbed amount of nutrients and nutritional status of rice plants at different growth stages were studied with respect to the nutrient contents and its relation to grain yield and yield components. This experiment was carried at three different level of nitrogen fertilization; two different seeding and transplanting times, and eight cultivars including both Japonica-and Tongil-type. The results of a part of these experiments are summarized as fallows: 1. The culm length tended to Increase with increasing fertilizer amount, but no significant difference between ordinary and heavy fertilization was observed in Tongil-type cultivars. 2. The panicle length was some what longer in ordinary and heavy fertilization than non-fertilization. 3. As the N-fertilizer level increases, the number of panicles per plant increased with higher response in Japonica-type cultivars than in Tongil-type cultivars. 4. The number of grains per panicle increased significantly in ordinary and heavy fertilization, compared to non-fertilization, but the difference in grain number per panicle among fertilizer treatment was smaller in Japonica-type cultivars than Tongil-type. 5. The 1,000 grains weight showed no significant difference among fertilization levels in ordinary transplanting, but indicated gradual decreasing tendency as the transplanting delayed. 6. In percentage of ripeness, there was no significant difference in ordinary transplanting, but hightly significant in late transplanting among N-fertilization levels and cultivars. 7. In yield, highly significant difference was shown among N-fertilizer levels and cultivars In Tongil-type variety, higher yield was obtained in ordinary fertilization than heavy fertilization. 8. The straw weight showed the tendency to increase in higher nitrogen level, but no significant difference between ordinaly and heavy fertilization was observed in Tonsil-type cultivars.