• 한국기후변화학회지
• /
• 제6권3호
• /
• pp.249-256
• /
• 2015

This study was conducted to investigate the effects of different levels and types of nitrogen fertilizer on seedlings and soil chemical properties in a semi-arid area, Mongolia. 2-year-old Populus sibirica and 4-year-old Ulmus pumila seedlings were planted in May 2014. Six treatments with three levels of nitrogen (low-level: urea $5g\;tree^{-1}$; medium-level: urea $15g\;tree^{-1}$, ammonium sulfate $33g\;tree^{-1}$, urea $15g\;tree^{-1}$ with potassium phosphate $10g\;tree^{-1}$; high-level: urea $30g\;tree^{-1}$) were applied and for the medium-level of nitrogen, different types of fertilizer were treated. Survival rate, root collar diameter (RCD) growth rate, leaf nitrogen concentration of seedlings, and soil chemical properties were determined in August 2014. The seedling survival rate of both species decreased as the level of nitrogen increased. This result can be explained by water stress caused by nitrogen fertilization in arid regions. The RCD growth rate of P. sibirica was significantly decreased by the treatment of high-level of nitrogen due to excessive nitrogen fertilization, and was increased by the treatment of ammonium sulfate due to sulfur which might promote nitrogen uptake. The leaf nitrogen concentration of P. sibirica did not change by the treatment of low-level of nitrogen, and was increased by the treatment of medium-level of nitrogen. There were no significant differences in the RCD growth rate and the leaf nitrogen concentration of U. pumila among the six treatments. None of soil chemical properties was affected by nitrogen fertilization. Overall, the low-level of nitrogen showed no effect on seedlings and soil chemical properties, except on survival rate of U. pumila and the high-level of nitrogen was considered excessive fertilization. Continuous monitoring of medium-level nitrogen fertilization including the ammonium sulfate, which increased early growth of seedlings, would be needed to elucidate the effect of fertilization on seedling growth and soil properties in a semi-arid region.

• 한국가축번식학회지
• /
• 제18권1호
• /
• pp.25-29
• /
• 1994

This study was carried out to investigate the in-vitro fertilization rate survival rate of rapidly frozen porcine immature embryos. The porcine embryos following dehydration by cryoprotectants containing sucrose were directly plunged into liquid nitrogen and thawed in 3$0^{\circ}C$ water bath. Survival rate was defined as development rate on vitro culture or FDA test. The results are summarized as follows : 1. The in vitro fertilization rate of all frozen immature oocytes(6.7~26.7%) was very low, 35.0% of unfrozen oocytes and the rate of immature oocytes was very higher than that of mature oocytes. 2. The survival rate of all frozen immature oocytes(10.3~25.0%, 13.3~30.0%) was very low, 45% of unfrozen oocytes and the rate of immature oocytes was slightly higher than that of mature oocytes.

• 한국토양비료학회지
• /
• 제47권6호
• /
• pp.547-552
• /
• 2014

This study was conducted to evaluate the influence of fertilization on characteristics of growth and accumulation of anthocyanin in fruit of Omija (Schisandra chinensis Baillon). Nitrogen supply mainly affected growth of fruit and the anthocyanin content in Omija respective of vegetative growth steps. The anthocyanin content in fruit was significantly low in high N supply and non-fertilization. The conjunctive supply of nitrogen and compost tea resulted in a higher anthocyanin content of fruit, total nitrogen content of leaf, and nitrate in soil. This result implies that nitrogen supply to Omija plant, affects the accumulation patterns of anthocyanin in different ways, e.g. it delays the quantitative biosynthesis at low nitrogen supply during fruit maturation or enhances anthocyanin degradation during the final maturation steps.

• 한국농공학회논문집
• /
• 제52권5호
• /
• pp.47-52
• /
• 2010

The purpose of this study is to investigate characteristics of total phosphorus (TP) and phosphate phosphorous ($PO_4$-P) concentrations in ponded water and redox potential (Eh) in paddy soil during the growing season. The TP and $PO_4$-P concentrations showed twice peak values after basal dressing and tillering fertilization. The ratio of $PO_4$-P to TP showed low values (0.07~0.18), indicating that most of phosphorus is particlulate. The $PO_4$-P concentrations significantly decreased with dissolved oxygen (DO) concentrations. The Eh showed high values (179~636 mV) under non-ponded aerobic condition, but low values (74~112 mV) under ponded anaerobic condition The TP and $PO_4$-P concentrations in ponded water increased shortly after tillering fertilization even if phosphorus was not applied. This may be due to the release of dissolved phosphorus from the bottom sediment and its associated algal and water flea blooms under anaerobic condition. Therefore, proper water management should be needed shortly after tillering fertilization.

• 한국작물학회지
• /
• 제51권spc1호
• /
• pp.67-72
• /
• 2006

본 시험은 벼 질소 소비 재배시 생육 및 쌀의 품질에 미치는 영향을 구명하기 위하여 일품벼 등 18종을 공시하여 관행 질소량 11.0 kg/10a와 소비 질소량 5.5 kg/10a로 구분하여 수행한 주요 결과는 다음과 같다. 소비 재배시 관행 재배에 비해 출수기는 1일 빠르거나 같았고, 초장은 $1{\sim}7cm$ 정도 작았으며, 경수, SPAD 치는 같거나 비슷한 경향이었다. 지상부 건물중은 새계화벼가 5.5kg/10a 시용시 주당 5.7 g적어 가장 큰 감소를 보였다. 수량은 470 kg/10a 이상 생산할 수 있는 품종은 일미벼, 남평벼, 신동진벼, 동진1호, 동안벼였다. 그러나 소비재배시 관행에 비해 수량 감소가 13% 이상 큰 품종은 주남벼, 동안벼였으며 수량 감소가 적은 품종은 수라벼, 화영벼 등이었다. 쌀 품위 및 식미 향상 품종은 화영벼, 추청벼, 일미벼, 일품벼 등 11품종이었다. 소비재배해서 쌀 수량 및 식미가 좋은 유망 품종은 동안벼, 일미벼, 일품벼, 동진1호, 새추청벼, 새계화벼였다.

• 한국가축번식학회지
• /
• 제14권4호
• /
• pp.245-252
• /
• 1990

This study was carried out to investigate the factors affecting fertilization in vitro of follicular oocytes with frozen-thawed spermatozoa in Korean Native Cattle. The bovine ovaries were obtained at a slaughter house and the follicular oocytes were recovered by aspirating the follicular fluid from the visible follicles of 3~6mm. The bovine oocytes were matured in vitro for 20~24 hours in TCM-199 containing FCS and hormones. The matured oocytes were fertilized in vitro using Percoll-separated frozen-thawed spermatozoa in BO solution. The effects of dilution and fertilization media, capacitating method, concentration of inseminated sperm and time after insemination of fertilization, were observed. The results obtained are summarized as follows : 1. The fertilization rate of frozen-thawed sperm inseminated in BO solution with caffeine and heparin together(56.4%) was higher than that of sperm inseminated in BO solution with either caffeine(10.5%) or heparin(8.9%) and without both caffeine and heparin(0%)(P<0.05). 2. The fertilization rate(56.3%) of frozen-thawed sperm inseminated in BO solution with both caffeine and heparin without preincubation was higher than that of sperm preincubated(2.9%)(P<0.05). 3. The fertilization with high concentration of frozen-thawed sperm(1.4~1.8$\times$107cells/ml) in BO solution containing caffeine and heparin resulted in higher fertilization rate, 76.7%, than the low concentration of sperm(0.8~1.0$\times$107cells/ml), 32.7%(P<0.01). 4. When the oocytes were inseminated with frozen-thawed sperm in BO solution containing caffeine and heparin without preincubation, fertilization rate increased by time and the rates were 5.9, 46.0 and 59.4% at 8, 16 and 24 hours, respectively.

• 한국환경농학회지
• /
• 제42권1호
• /
• pp.28-34
• /
• 2023

Nitrogen fertilizers applied to agricultural lands for crop cultivation can be volatilized as ammonia. The released ammonia can catalyze the formation of ultrafine dust (particulate matter, PM2.5), classified as a short-lived climate change pollutant, in the atmosphere. Currently, one of the prominent methods for fertilizer application in agricultural lands is soil surface application, which comprises spraying the fertilizers onto the soil surface, followed by mixing the fertilizers with the soil. Owing to the low nitrogen absorption rate of crops, when nitrogen fertilizers are applied in this manner, they can be lost from land surfaces through volatilization. Therefore, investigating a new fertilization method to reduce ammonia emissions and increase the fertilizer utilization efficiency of crops is necessary. In this study, to develop a method for reducing ammonia emissions from nitrogen fertilizers applied to soil surfaces, deep fertilization was conducted using a newly developed deep fertilization device, and ammonia emissions from barley, garlic, and onion fields were examined. Conventional fertilization (surface application) and deep fertilization (soil depth of 25 cm) were conducted for analysis. The fertilization rate was 100% of the standard fertilization rate used for barley, and deep fertilization of N, P, and K fertilizers was implemented. Ammonia emissions were collected using a wind tunnel chamber, and quantified subsequently susing the indole-phenol blue method. Ammonia emissions released from the basal fertilizer application persisted for approximately 58 d, beginning from approximately 3 d after fertilization in conventional treatments; however, ammonia was not released from deep fertilization. Moreover, barley, garlic, and onion yields were higher in the deep fertilization treatment than in the conventional fertilization treatment. In conclusion, a new fertilization method was identified as an alternative to the current approach of spraying fertilizers on the soil surface. This new method, which involves injecting nitrogen fertilizers at a soil depth of 25 cm, has the potential to reduce ammonia emissions and increase the yields of barley, garlic, and onion.

• 한국가축번식학회지
• /
• 제13권2호
• /
• pp.98-104
• /
• 1989

Successful techniques of in vitro fertilization(IVF) are valuable for studying the process of fertilization and for developing economical procedures for gene and nuclear transfer in farm animals. To date, bovine IVF system has been developed with oocytes in vitro or vitro, but the resulting zygotes exhibit limited embryonic development after in vitro culture. Even though in vitro matured oocytes achieved high fertilization and cleavage rates, these embryos appear extremly low rate of pregnancies when transferred to synchronized recipients. Development of early bovine embryos in vitro is generally arrested at the 8-to 16-cell stage. However, recent use of somatic cells such as trophoblastic vesicle, granulosa and oviduct epithelial cell for co-culture with early bovine embryos has proven effective for development of embryos, matured and fertilized in vitro, past the in vitro cell blocks. These factors clearly indicate the value of the co-culture system in promoting development of bovine oocytes matured and fertilized in vitro to morula or blastocyst stage in vitro. In addition, co-culture system may beome a tool for evaluation of viability of ova that have been manipulated by procedures such as splitting, microinjection and nuclear transfer.

• 생물환경조절학회지
• /
• 제12권1호
• /
• pp.17-21
• /
• 2003

참외재배시 저광도 조건시 상품수량의 급격한 저하를 막기 위하여 본 연구가 수행되었다. 과실 비대기에 해당되는 착과후 10일부터 400 $\mu$mol$.$m$^{-}$2$.$S$^{-1}$정도의 저광도 조건이 지속되면 광합성 속도도 떨어지고, 엽록소 함량도 낮았으며 특히 요소 무엽면시비구의 광합성속도는 크게 저하되었다 당도에 있어서는 자연광에 비해 저광도 처리구가 전반적으로 낮았는데, 착과수가 많고 무엽면시비구일수록 낮았다. 발효과 발생률은 요소 엽면시비 유무에 관계없이 자연광에서는 4% 미만으로 발생되었는데, 저광도 조건에서는 10% 이상 발생되었다. 특히 저광도 조건에서 적과수를 적게 한 처리구일수록 발효과 발생률이 높았는데, 적과를 하지 않은 처리구는 각각 39와 48%로 매우 높은 발생율을 보였다. 수확시기 지연은 요소 엽면시비 유무와 관계없이 자연광에 비해 저광도 조건에서 늦어지는 경향을 보였는데, 적과수가 적을수록 지연정도는 심했다 주당 상품수량에 있어서는 저광도 조건하에서 자연광에 비해 16∼34% 수준 정도로 매우 낮은 수량을 보였는데, 요소 0.5% 액을 엽면시비하고 2개를 적과한 처리구가 34%수준으로 자연광에 비해 다른 처리보다 높은 상품수량을 보였다. 따라서 참외재배시 과실 착과후 10일경부터 강우 등에 의해 장기간 저광도 조건이 지속될 것으로 전망되면 상품수량의 급격한 저하를 막기 위하여 주당 6개의 착과 과실중에서 2개를 적과하고, 요소 0.5%액을 2회 정도 엽면시비 해주는 것이 바람직 할 것으로 사료된다.

• 한국초지조사료학회지
• /
• 제8권1호
• /
• pp.40-46
• /
• 1988

This study was carried out to determine the effects of nitrogen (N) fertilization levels (0, 100 and 200kg/ha) and formaldehyde (0.4,0.8 and 1.2%: w/w CM) on the chemical composition, dry matter (DM) yield and in-vitro dry matter digestibility (IVDMD) of forage rape (Brassica napus Subsp. oleifera) silage. The results obtained are summarized as follows : 1. Forage rape was a catch crop which was highly digestible and low concentration in NDF, ADF, cellulose and lignin. 2. The concentration of the water soluble carbohydrate (WSC) and buffering capacity (PK) was 17.9% and 6.77g/100g, respectively, provided the WSC to PK ratio was 2.65. 3. DM content of silage decreased as the rate of N fertilization increased, but concentration of ammonia-N decreased. IVDMD was not affected by the rate of N fertilization. 4. By the addition of formaldehyde, the pH and IVDMD were increased, but the DM, lactic acid, total organic acid and ammonia-N content of rape silage were decreased, that was effective as a silage additive for forage rape.