• Journal of Plant Biology
• /
• v.16 no.1_2
• /
• pp.30-38
• /
• 1973

To study the response to plant growth by the environmental factors, the effects of application of nitrogen on changes in the yield, crude protein, amino acids, chlorophyll, carotene, total phosphorus, acid-soluble phosphorus, phospholipids, RNA, and DNA were investigated with westerworlds 9Lolium sublatum) and perennial rye-grasses (Lolium perenne). The amounts of dry weight, crude protein, amino acids, chlorophyll, carotene, total phosphorus, acid-soluble phosphorus, phospholipids, RNA and DNA of both rye-grasses increased with adequately increasing nitrogen, and reached a maximum with an adequate application of nitrogen. The relationships between yields and crude protein contents, crude protein and RNA contents, and yields and RNA contents of westerworlds and perennial rye-grasses were found to be positively correlated, respectively. Therefore, in general, the response to plant growth by the environmental factors such as nitrogen nutrient may be summarized as follows: Environmental factors\longrightarrowDNA\longrightarrowRNA\longrightarrowProtein\longrightarrowPlant growth

• Food Science and Preservation
• /
• v.5 no.2
• /
• pp.127-132
• /
• 1998

In order to fad out an efficient way of topdressing nitrogen fertilizer in mulch-cropping system of onion(Allium cepa L.), solid, slow-release, and liquid forms of nitrogen fertilizers were allied to cv. 'Changnyungdaego' various number of times at different time, with 5 topdress applications of solid fertilizer serving as a control. Whole basal application of conventional solid fertilizer and 2 slow-release fertilizers were labor-saving and showed improved storage quality of bulbs, but resulted in poor plant growth and considerably low yield due to fertilizer shortage from early April. This suggests that topdress application is necessary. Liquid form of nitrogen fertilizer was more effective for plant growth and yield and saving labor than the solid form. Early applications was effective for increasing yield and storage quality of onion bulbs harvested. Thus two applications of liquid form of nitrogen fertilizer in February and March at rome month interval are recommended in mulch crowing system of onion.

• Journal of the Korean Society of Tobacco Science
• /
• v.4 no.1
• /
• pp.29-35
• /
• 1982

Potassium deficiency symptoms were studied with flue-cured tobacco which was applied with different levels of compound fertilizer (10-15-20) ; 75kg, 100hg, and 125kg/10a. Ratio of N/$K_2O$ in leaves was increased from bottom to top stalk position due to the increase of nitrogen content in leaves. Nitrogen content in leaves was increased from stalk to tip as wall as from midrib to laminae, but vice versa in potassium content. Consequently, resulting in potassium deficiency symptoms in tip of leaves. Rate of reabsorption by rainfall during the latter part of growth was highest at top stalk position in case of nitrogen, but lowest in potassium. This observation was more evident with higher application rate of fertilizer. Nitrogen content of about 4 % in leaves of top stalk position applied with 125kg/10a was maintained up to 85days after trans planting. No increase in potassium in upper leaves was observed over the level of 100kg/10a fertilizer application. As the result, N/$K_2O$ ratio in leaves of top stalk position applied with 125kg/10a was kept at more than 1.0 up to 85days after transplanting, but it was less than 0.9 at 65days after tracts planting with less than 100kg/10a fertilizer application.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.27 no.1
• /
• pp.66-71
• /
• 1982

Field experiments of nitrogen application (0, 100, 200, 400, 800kg N/ha year) were carried out to study the nitrogen response of Sudangrass at College Farm, Seoul National Univ., in 1979 and 1980. Dry matter yield and leaf area index increased up to 400kg N/ha in 1979 and 800kg N/ha in 1980. The forage yield of 1980 was less than that of 1979, due to the extraordinarily low temperature and the decreased solar radiation during summer. Total nitrogen contents in forage increased with nitrogen application, but maximum contents were found either 400 or 800kg N levels depend on each cutting stages. Nitrate nitrogen content in forage exceded over 2000 ppm at 800kg N application. Overall percentages of N recovery were below 50% with average 34%. Net assimilation rate and nitrogen use efficiency of Sudangrass were improved in higher temperature and more sunlight condition during regrowth period.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.51 no.1
• /
• pp.32-40
• /
• 2006

The nitrogen (N) absorption and partition of the rice plants are important indicators that can be used to improve the N use efficiency (NUE) of the plants. Improving the plant NUE can help to avoid nutrient waste that may cause environmental pollution. To investigate the N absorption and partition of the rice plants, Hwaseongbyeo (Japonica) and Dasanbyeo (indica/japonica) were applied with N fertilizers at the rates of 60, 120, and 180 kg N per ha in paddy field. Also micro plots of $0.81m^2$ were established inside each plot for application of $^{15}N-labeled$ fertilizer. The differences in N utilization of the rice plants were associated with the total N absorption and partitioning after the heading stage. In the grain filling period, the increase of nitrogen content in the total and leaf blades of Dasanbyeo was higher than that of Hwaseongbyeo. Soil N was the main contributor for the increase of total N of Dasanbyeo during the grain filling period. The N fertilizer uptake rate of Hwaseongbyeo rapidly increased with the increment of N fertilization rate. In Dasanbyeo, N fertilizer uptakes were similar under all rates and times of N application. From heading stage to harvest, Dasanbyeo continued accumulating nitrogen, whereas Hwaseongbyeo had small changes. In conclusion, the difference in nitrogen absorption and partition after heading of the two cultivars was caused by the ability of Dasanbyeo to accumulate and remobilize soil nitrogen to the grains during the grain filling period.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.58 no.2
• /
• pp.169-176
• /
• 2013

Preharvest sprouting seriously reduces milling and baking quality of hard winter wheat (Triticum aestivum L.) grain. To determine the effect of nitrogen fertilizer application on decreasing of preharvest sprouting, several levels of N-fertilization were conducted in two winter wheat cv. Keumkang and Jokyung, grown in Iksan. Nitrogen fertilization is used to increase grain yield and protein content. Grain yield increased at 108kg/ha (50% increased nitrogen to the standard) application and decreased as more nitrogen was applied. There was a linear increase in grain protein contents with increasing level of nitrogen application. Germination rate, germination index and ABA sensitivity were gradually reduced by increasing of nitrogen application level. Preharvest sprouting showed a significantly correlation to germination rate but could not be correlated to protein content and falling number. A significant positive correlation was detected between preharvest sprouting and different additional nitrogen fertilizer levels.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.19 no.2
• /
• pp.147-154
• /
• 1999

A field experiment with 200, 400 and 600kg-N/ha/year application levels was carried out to study the nitrate nitrogen accumulation of sorghum sudangrass hybrids(Xtragraze II and Civa 1990) at Iksan College Farm in 1995. The nitrate nitrogen content of Xtragraze II and Civa 1990 was increased by the application of nitrogen and decreased as the plant matured, then the nitrate nitrogen content was below the toxic level of ruminant at the level of 200kg-N application during the whole growing period. The nitrate nitrogen content of Xtragraze II and Civa 1990 exceeded the safe level of ruminant at the level of 400kg-N application, and that in Xtragraze II decreased at the low level in the later stage of growth, but that in Civa 1990 was almost kept constantly at the same level. The nitrate nitrogen accumulation of Civa 1990 had a greater tendency than that of Xtragraze II. A sum exceeding 200kg-N does not necessarily result in increase the amount of nitrate nitrogen in sorghum sudangrass hybrids. It is suggested that 400kg-N application may results in toxic level of nitrate nitrogen, and special attention must be given in feeding them.

• Korean Journal of Soil Science and Fertilizer
• /
• v.38 no.4
• /
• pp.194-201
• /
• 2005

Silicate (Si) fertilizers are well-known for soil amendment and to improve rice productivity as well as nitrogen efficiency. In this study, we investigated the possible reduction level of nitrogen fertilization for rice cultivation by amending Si fertilizer application. Field experiments were carried out to evaluate the productivity of rice (Oryza sativa L.) on a silt loam soil, where three levels of nitrogen (0, 110 and $165kg\;ha^{-1}$) were selected and Si fertilizer as a slag type was applied at 0, 1 and 2 times of the recommendation level (available $SiO_2\;130mg\;kg^{-1}$). Application of Si fertilizer increased significantly the rice yield and nitrogen efficiency. With increasing N uptake of rice, 1 and 2 times of recommended levels of Si fertilization could decrease nitrogen application level to about 76 and $102kg\;N\;ha^{-1}$ to produce the target yield, the maximum yield in the non-Si amended treatment. Silicate fertilizer improved soil pH and significantly increased available phosphate and Si contents. Conclusively, the Si fertilizer could be a good alternative source for soil amendment, restoring the soil nutrient balance and to reduce the nitrogen application level in rice cultivation.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.8 no.3
• /
• pp.67-72
• /
• 2005

For the two species of native fern that have high development potential for interior landscape, Rumohra aristata and Cyclosorus dentatus, the physiological and growth characteries as nitrogen application rate such as $NaNO_3$ 0.0mg/L, $NaNO_3$ 0.5mg/L, $NaNO_3$5.0mg/L, $NaNO_3$ 50mg/L and $NaNO_3$ 500mg/L were surveyed. 1. A significant changes of Rumohra aristata, in top growth was not distinctive. However, as nitrogen application rate increased, the numbers of leaves declined and the content of chlorophyll and the number of wilted leaves increased. 2. As nitrogen application rate increased, the top growth of Cyclosorus dentatus and the content of chlorophyll was increased. However, its overall, ornamental value was reduced due to the rising number of wilted leaves and the declining number of new leaves.

• Asian Journal of Turfgrass Science
• /
• v.6 no.1
• /
• pp.39-45
• /
• 1992

This experiment was undertaken to study effect of fall Fertitizarion on spring regrowth of Korean lawngrass( Zoysia japonica Steud ) Results obtained are summarized as follows : 1. late fall fertilization stimulated the spring regrowth of Korean lawngrass. hut early spring application showed little effect on that 2. The yield of clippings on May 21 was obviously greater in late fertilization plots(treatment C, D and E) than other plots(treatment A, B and control, but there was no significant difference in clipping yields of C, D and F treatment. 3. Both nitrogen and reducing sugar contents of runner fell down in spring. It was suggested thatthese constituents be translocated from runner to other parts during the budding period. 4. The nitrogen content of runner was obviously mote in the plot of late fall fertilization. In contrast to nitrogen, no obvious difference was found in reducing sugar content of runner of seven application date. It was suggested that the roots of plant be still able to absorb to absorb nitrogen under dormancy. .5.From these results. late fall fertilization enhances the development of Korean lawngrass in the following spring. But early spring application shows little effect on spring regrowth.