This study was carried out to study the effect of supplementary nitrogen fertilization application time according to regrowth date on growth date on growth characteristics, feed value, and productivity of Italian ryegrass (Lolium multiflorum Lam.; IRG) from 2019 to 2021 in Cheonan region. In order to determine the regrowth time, IRG was cut from experimental plots 3cm above soil level and the time when 1cm grew was judged as the regrowth time. The regrowth dates were February 15th and February 12th in 2020 and 2021 respectively. The experimental design was a randomized block design with three replications. The treatments were no fertilizer, immediately after the regrowth period, after 10 days of the regrowth period, and after 25 days of the regrowth period. Dry matter yield of IRG was significantly influenced by the supplementary N-fertilization application time. Dry matter yield was reduced for the delayed application time. The dry matter yield of immediately after the regrowth period was approximately 34.8 % higher than that no fertilizer application. In delaying the supplementary N-fertilization application time resulted in increased crude protein content. However, no significant statistical difference was neutral detergent fiber and acid detergent fiber(p>0.05). After wintering, productivity of IRG reduced for the delayed application time. Therefore, it is essential to application N-fertilizer immediately after the regrowth period for high productivity of IRG.

Presently, the effect of 0.5 mM dibutyryl cAMP (dbcAMP)-supplemented maturation medium during different incubation time on meiotic arrest (germinal vesicle) and resumption (metaphase II) of porcine oocytes and embryonic development of porcine oocytes following in vitro fertilization (IVF) or parthenogenetic activation (PA) was determined. Porcine cumulus oocyte complexes (COCs) were cultured in 0.5 mM dbcAMP for 17, 22, 27, or 42 h, and an additional 22 h without 0.5 mM dbcAMP. The nuclear status was examined at each time point. Oocytes cultured from 39~49 h displayed more than 80% meiotic resumption. More than 85 % of meiotic arrest was presented at 17~22 h. Oocytes were cultured for 22 h with 0.5 mM dbcAMP and additional 22 h without dbcAMP to assess developmental potential following IVF or PA. There were no significant differences in blastocyst rates among the dbcAMPIVF, IVF, dbcAMP-PA, and PA groups, although cleavage rate of IVF group was significantly higher than those of dbcAMP-PA, and PA groups. In conclusion, 0.5 mM dbcAMP influenced meiotic maturation of porcine oocytes depending on incubation time of oocyte, although embryonic development was not improved in both IVF and PA.

These study was carried out to investigate the effects of the recovery time, diameter of oocytes on in vitro fertilization or intracytoplasmic sperm injection (ICSI). The in vitro maturation rates to MII stage of oocytes recovered at the inactive, follicular and luteal stages matured for 72 h were 1.4±0.0%, 43.4±3.2% and 10.8±2.7%, respectively. The fertilization rates of in vitro cultured oocytes recovered from ovaries at the in active, follicular and luteal stages were 0.0±0.0%, 15.7±3.4% and 7.6±3.5%, respectively. The in vitro maturation rate of oocytes recovered from ovaries at the follicular stage of the reproductive cycle was significantly higher than those at the inactive and luteal stages (p<0.05). The penetration rate determined that the percentages of oocytes with diameters in the <100 μm, 100 to 100 μm and 110 to 120 μm ranges were 17.5±4.7%, 43.9±4.5%, 21.3±3.4%, respectively. The penetration rate of oocytes with diameters between 100 to 110 μm was significantly higher than that of oocytes whose diameters were 100< μm and 110～120 μm (p<0.05). The penetration rate of oocytes determined that the percentages of ovaries with diameters between 1 to 5 mm and 6 to 10 mm were 32.9±3.2% and 17.5±3.7%, respectively. Thus, the diameters of the ovaries were significantly higher at 1 to 5 mm (p<0.05). A total of 264 oocytes were fixed and stained after co-incubation with sperm, of which 72 had identifiable nuclear material. After in vitro fertilization for 20 hrs, 27.3% of oocytes were penetrated by spermatozoas. Oocytes were fixed and stained after ICSI, of which 38 oocytes contained identifiable nuclear material. After in vitro fertilization and ICSI for 20 hrs, to 27.3% and 67.9% of oocytes were penetrated by spermatozoas. The in vitro fertilization rates by ICSI was significantly higher than that in vitro fertilization method (p<0.05).

The techniques of IVM, IVF and IVC of canine oocytes may provide useful information for gamete salvage programs and the conservation of endangered canidae. This investigation has been made to determine the efficiency of in vitro maturation (IVM) as a basic experiment to study the development of canine oocytes after in vitro fertilization (IVF). The rate of oocytes developing to the MII stage was higher in the hormone treated group (10 IU/ml hCG+eCG, 14.7%, p<0.05) than in the control group (0 IU/ml hCG+eCG, 10.0%). The monospermy and pronuclear rates of canine oocytes were investigated after caffeine treatment on IVF. Canine oocytes were fertilized in the Fert‐TALP medium supplemented with 0, 10, 20 or 30 mM caffeine (Fert I, Fert II, Fert III or Fert IV, respectively). The highest pronuclear formation rate was obtained in the Fert I for 24 h IVF (6.7%, 6/89). Therefore, it is believed that unlike in other mammals, caffeine in canine IVF does not increase the efficiency of fertilization rate, and is not an important factor.

본 연구는 돼지 체외 수정란의 생산에 있어서 체외성숙 시간이 핵성숙, 다정자 침입율 및 배 발생과 배반포의 부화율 배반포의 부화에 미치는 효과를 검토하였다. 돼지 난포란의 핵성숙율이 체외성숙 36, 38, 40, 42 및 44 시간째에 각각 68.0, 78.0, 79.5, 73.8 및 81.8%로서 각 군간에 유사한 경향이었으며, 체외 수정 후 다정자 침입율도 각각 48.7, 36.0, 44.4, 38.9 및 31.8%로서 차이가 없었다. 체외 성숙 시

본 연구는 체외성숙된 돼지난포란을 액상정액으로 수정시 수정시간과 배양배지가 난포란의 발달에 미치는 영향을 조사하기 위하여 실시하였다. 정자농후정액 (30∼60 ml)을 채취하여 실온에서 2시간 정도 서서히 냉각시킨 후, 정액을 15 ml 튜브에 담아 800×g로 10분간 원심분리하였다. 상층액은 버리고 하부의 정자는 5 ml LEN 희석액으로 1×10/sup 9/ 전자/ml가 되도록 재희석하였다. 희석된 정액은 4℃ 냉장고에 보존하였다. 미성숙 난모세포의 성숙에 사용된 배지는 26.19 mM sodium bicarbonate, 0.9 mM sodium pyruvate, 10 ㎍/ml insulin, 2 ㎍/ml vitamin B/sub 12/, 25 mM HEPES, 10 ㎍/ml bovine apotransferrin, 150 μM cysteamine, 10 IU/ml PMSG, 10 IU/ml PMSG, 10 IU/ml EGF, 0.4% BSA, 75 ㎍/ml sodium penicillin G, 50 ㎍/ml streptomycin sulfate그리고 10% pFF를 첨가한 TCM-199 배지였다. 22시간 성숙 배양한 후 난모세포는 cysteamine과 hormone들을 배제한 후 38.5℃, 5% CO₂ incubator에서 22시간 더 성숙시켰다. 성숙된 난모세포는 채취 후 2일간 4℃에 보존된 액상정액으로 수정되었다. 난모세포는 500 μl mTBM 수정 배지에서 1×10/sup 6/ 정자/ml의 농도로 1, 3, 6 그리고 9시간 동안 수정시켰다. 그 후 난모세포는 500 μl NCSU-23, Hopes buffered NCSU-23, PZM-3 그리고 PZM-4 배양배지에 옮겨서 6, 48 그리고 144시간을 더 배양하였다. 정자침투율, 웅성전핵형성율 그리고 난모세포의 난할율은 6 및 9시간 수정시간에서 1 및 3시간 수정시간 보다 높았다. 6시간 수정시 배반포형성율 (33.6%)은 1, 3 그리고 9시간 수정시 배반포형성율 (11.4, 23.0 그리고 29.6%) 보다 높았다. 배반포의 평균세포수는 6, 9, 3 그리고 1시간 수정시 각각 32.9, 27.6, 26.3 그리고 24.4개 였다. 분할된 난모세포의 배반포형성율 그리고 배반포의 평균세포수는 NCSU-23, PZM-3 그리고 PZM-4 배양배지보다 HEPES buffered NCSU-23 배양배지가 우수하였다. 결론적으로 4℃ 보존 돼지액상정액은 체외성숙된 돼지 난모세포의 체외수정에 사용될 수 있음이 입증되었다. 또한 체외성숙된 돼지 난모세포는 500 μl mTBM 수정배지에서 1×10/sup 6/ 정자/ml로 6시간 공배양시키는 것이 바람직하며, HEPES buffered NCSU-23 배양배지에서 배양하는 것이 좋다는 결과를 얻었다.

본 연구에서는 in vitro에서 성숙된 난자의 핵성숙(Polar Body extrusion)에 소요되는 시간과 배반포 단계로의 발달능력 사이의 관계를 비교하여 조기에 발달능력을 가진 embryo를 선발할 수 있는 IVP 체계를 개발하고자 하였으며 in vitro maturation(IVM)에 따른 first polar body(PB) 형성, IVM과 IVF 시간이 oocyte의 발달에 미치는 영향과 생산된 배반포의 세포수를 평가하였다. IVM은 TCM199 배양액을 사용하였고 in vitro fertilization(IVF)은 Fer -TALP용액을 사용하였으며 in vitro culture(IVC)는 CRlaa 배양액을 사용하여 2일까지는 0.3% BSA를 3일 부터는 10%FBS와 bovine oviduct epithelial cell을 첨가하여 배양하였다. IVM 시간에 따른 PB의 출현율은 0hr(0%), 6hr(0%), 12hr(0%), 14hr(8.7%), 16hr(40.5%), 18hr(48.0%), 20hr(65%), 22(68%) 그리고 24hr(74.5%)을 보였으며 IVM 시간에 따른 cleavage 및 8cell 발달율 사이에는 유의적인 차이가 없었으나 배반포(BL) 및 8cell에서 배반포로 발달률은 18시간(BL 316, BL/8cell 82 5%)에서 가장 높게 나타났으며 24시간(BL 172, BL/8cell 608%)과 유의적인 차이를 보였다(P<0.05). IVC 7일째 배반포의 총세포수와 trophoblast(TE) 세포수는 IVM 18시간(meanS.E.; total: 131.134.0, TE: 97.629.6)에서 24시간(total: 112.217.5, TE: 80.115.6)보다 유의하게 많은 것으로 나왔으나(P<0.05) 7일째의 inner cell mass(ICM) 숫자(18hr 33.512.8 vs 24hr 32.112.0)와 8일째 ICM, TE 그리고 총 세포수에는 유의성 있는 차이가 없었다. IVM 18시간에서 PB 형성과 8cell 발달률 사이에 높은 상관성을 보였고 배반포 및 8cell에서 배반포 단계로 높은 발달률을 보였으며 생산된 배반포의 TE 숫자와 총 세포수가 유의하게 많은 것으로 나타났다. 따라서 IVM 18시간 실시하였을 경우 보다 많은 세포수를 가진 배반포 발달 가능성이 높은 embryo를 조기에 선발 가능할 것으로 사료된다.

This study was conducted to investigate the effects of preincubation time, concentration and exposure time of sperm on in vitro fertilization of porcine follicular oocytes rnatured in in vitro. The results obtained are as follows ; 1. Effect of preincuhation time for porcine sperm capacitation on in vitro fertilization in medium with heparin was investigated. Normal fertilization rate was highest in 15 min(26.4%). However, there were no significant differences among preincuhation times of 5~90 min, 2. Normal fertilization rates of sperm concentrations were 17.0~26.5%, and normal fertilization rate from l l05cell /ml concentration was also higher than those of other sperm concentration. 3. Normal fertilization rates of sperm exposure time of 4, 8, 12, 16 and 20 hours were 6.1, 20.8, 27.8, 25.0 and 26.7%, respectively. Normal fertilization rate from sperm exposure time of 12 hours was also higher than that of other sperm exposure times.

This field experiment was carried out to determine the effects of fertilizer application time in spring on the growth, crude protein (CP) content and dry matter (DM) yield of gasses for grazing Application times of fertilizer were on March 10, March 20, M

Background : Medicinal crop seeds have low homogeneity and quality of seeds and seedlings because they are self-seeded or produced in farmhouses. Therefore, it is necessary to develop systematic technology for establishment and distribution of seed production technology for stable production of domestic medicinal crops. Methods and Results : The test Agastache rugosa O. K. Kuntze. variety was Jeonnam local variety (Naju species) and was carried out in 2017. The research was divided into two types; seed yield test according to seeding time and seed yield test according to fertilization method. Sowing of the seed yield test according to the seeding time was sown on the seedling tray 4 times from 20 th March to 20 th May at intervals of 20 days, and after the nursery, they were transplanting. The fertilization gave the standard fertilization (N-P-K-compost applied at 12-16-10-600 ㎏/10a) amount before implantation. Sowing of the seed yield test according to fertilization method was sowing in the middle of April. The seedlings were grown for 60 days and then transplanted in the middle of June. Four different fertilization methods were applied and cultivated. Planting density of both tests were spaced 30 ㎝ apart in rows 20 ㎝ apart with non-woven fabric mulching cultivation. The plot design was a randomized block 3 repetitions. Seed yields at the seeding time were the highest at 67 ㎏/10a in sowing on March 20, and the yields decreased as the seeding time passed. Seed yield according to fertilization method was the highest at 75 ㎏/10a in 25% increase control and lowest at 46 ㎏/10a in 50% diminish control. Conclusion : From the above results, we may suggest that the seedlings should be cultivated in the middle of March and cultivated by increasing the fertilization rate by 50%.

새로운 노지 월동작물과 수출유망 작물을 개발하기 위하여 shallot을 도입하여 적응력 시험을 수행하고 있는 과정에서 몇 가지 문제점이 발견되었다. 이러한 문제를 해결하고 질소 시비량과 추비 시기가 shallot의 생육에 미치는 영향에 대해 조사하기 위해 수행하였다. 질소 시비량은 10 a 당 24 kg이 적당하였고, 추비는 2월과 3월에 각각 1회씩 시용하는 것이 효과적이었다. 질소 시비량이나 추비 시기에 따른 식물체의 무기성분 함량은 차이가 없었다.

This study was carried out to investigate the optimum application time of basal fertilization in direct-seeded rice on flooded paddy surface at medium saline soil in southwestern reclaimed saline area which is Munpo series and have 0.3 or more soil salinity. The nitrogen fertilizer level were 14, 17, 20kg per 10a, and the basal fertilization were applied before sowing, 10, 20, 30 days after sowing along with topdressing at tillering stage, respectively. The summarized experimental results are as follows. Seedling stand was proper when basal fertilization was applied before sowing, but lower than appropriate seedling stand when basal fertilization were applied 10, 20, 30 days after sowing along with topdressing at tillering stage. The rice yield were 509-541kg/10a when 14-20kg/10a basal fertilization was applied before sowing, and 368-481kg/10a when basal fertilization were applied 10, 20, 30 days after sowing along with topdressing at tillering stage. Considering the yield and salt injury at medium saline soil in southwestern reclaimed saline area, the application of basal fertilization before sowing was superior for improving seedling stand, and 14-20kg/10a fertilization rate was allowable.

남부지방에서 황금재배시(黃芩栽培時) 적심시기(摘芯時期)와 질소, 가리의 추비방법에 의한 증수효과(增收效果)를 구명하고자 여천(麗川) 재래종(在來種)을 공시(供試)하여 재식거리(裁植距離)를 4×10cm로 4~5립(粒)을 4월 1일에 점파하였고 적심시기(摘芯時期)는 무적심구(無摘芯區)와 7월상순 1회 적심(摘芯), 7월상순과 8월중순에 2회 적심(摘恣)한 3처리에 대해 기비(基肥) : 추비(追肥) 비율(比率)을 70% : 30%, 60% : 20+20%, 50% : 20+20+20%으로 하여 시험을 수행한 결과를 요약(要約)하면 다음과 같다. 1. 토양의 화학성을 보면 시험후 토양이 시험전 토양에 비해 유기물(有機物), 유효린산(有效燐酸), 가리, 칼슘, 마그네슘, C. E. C 함량이 증가되는 경향을 보였다. 2. 적심시기(摘芯時期) 및 분시방법간(分施方法間)의 생육은 7월상순과 8월중순에 적심직후(摘芯直後) 2회 추비(追肥) 시용구가 무적심(無摘芯)의 7월상순 1회 추비(追肥) 시용구에 비하여 경장(莖長)들은 짧았으나 분지수(分枝數,) 경태(莖太등) 지상부와 주근장(主根長), 상근중(上根重) 비율(比率) 등 지하부 생장량이 증대되었다. 3. 건근수량(乾根收量)은 무적심(無摘芯) (158kg/10a)에 비해 2회 적심구(摘芯區)가 15% , 1회 적심구(摘芯區)가 10% 증수(增收)되었으며 질소, 가리 비료의 분시방법간(分施方法間)에는 2회 추비(追肥) 시용구가 1회 추비(追肥) 시용구 (150kg/10a)에 비해 상근중(上根重) 비율(比率) 향상으로 29% 증수(增收)를 보였다. 4. 2회 적심(摘芯) 처리에서 건근수량(乾根收量)은 경장(莖長)과 주당(株當) 생경엽중(生莖葉重), 지상부 생육간(生育間)에 질(負)의 상관(相關)이 인정되었고 주당(株當) 분지수(分枝數) 및 주근량(主根長)및 상근중(上根重) 비율(比率)과는 밀접한 정(正)의 상관(相關)을 보였으며 2회 추비(追肥) 시용재배에서도 경장(莖長), 주당분지수(株當分枝數) 및 주근량(主根長), 주근경(主根徑)등 지상, 지하부 생육과 건근수량간(乾根收量間)에 고도의 유의성이 인정되었다.

팔굉, 노풍, TN1 3품종을 공시하여 20℃ 하에서 인공수분하여 수정과정을 조사하고, 상기 3품종외 이외326, 밀양29, 수원264등 9개품종을 일반포장에서 이앙기를 달리하여 감戮수분열과 등숙비율을 조사한 결과는 단음과 같다. 1 팔굉은 30℃ 하에서는 수분후 1시간30분에서 4시간후에, 20℃ 하에서는 2시간30분에서 4시간30분후에 수정이 된다. 2. 노풍과 TN1은 30℃ 하에서는 2시간에서 5시간30분후에, 20℃ 하에서는 수분후 3시간에서 6시간후에 수정이 된바. 3. 저온인 20℃ 하에서는 수정률이 저하하고, 특히 TN1에서는 극핵과 정핵 또는 난세포와 청핵의 수정이 거의 동시에 되는 것과 어느 한편만 수정이 되는 때도 있다. 4. 조발육에 있어서는 20℃ 하에서는 팔굉이 빠른 것 같고, 30℃ 하에서는TN1이 빠른 것 같다. 5. 팔굉은 이앙기가 늦어도 감수분열에 이상이 없이 정상화분립을 형성하나, TN1은 감수분열에 이상이 있어 불념화분립수가 많아진다.