• 한국환경농학회지
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• 제39권4호
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• pp.360-367
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• 2020

BACKGROUND: The productivity and quality of blueberry (Vaccinium ashei Reade) greatly depend on the number of fruits in a plant. Especially, fruit set more than appropriate number negatively affects productivity and marketability due to the increased number of small fruits and delayed harvest time. This study was conducted to investigate proper timing and concentration for applying chemical blossom thinners such as ammonium thiosulfate (ATS) and UREA. METHODS AND RESULTS: ATS at 1.25% and 1.50%, and UREA at 6% and 8% were applied in four developmental stages, bud swell, pink bud, full bloom and petal fall. Fruit thinning rate was calculated based on the number of fruits harvested divided by that of flowers before applying blossom thinners. Ratios of leaf to flower and leaf to fruit were calculated based on the number of fully developed leaves in 25 days after full blossom divided by that of flowers or fruits, respectively. Chemical injury of leaves was investigated by calculating the number of leaves with chemical injury divided by the total number of leaves. Fruit thinning rates were 48% and 66% for UREA treatments at 6% and 8%, respectively, and 49% and 62% for ATS treatments at 1.25% and 1.50%, respectively, in the full bloom stage. In the petal fall stage, fruit thinning rates were 18% and 24% for UREA treatments at 6% and 8%, respectively, and 49% and 35% for ATS treatments at 1.25% and 1.50%, respectively. Leaf to fruit ratio (L/FR) increased by 109% and 188% compared to leaf to flower ratio in ATS treatments at 1.25% and 1.50%, respectively, and L/FR increased 93 and 196% in UREA treatments at 6% and 8%, respectively, in the full bloom stage. In the petal fall stage, leaf to fruit ratio increased by 60% to 100% in ATS treatments, but did not significantly differ from the control in UREA treatments. Fruit harvest was delayed in all treatments of all developmental stages except for 1.5% ATS and 6% UREA treatments at the petal fall stage, whose fruit harvest was two or three days faster than the control. CONCLUSION: The application of ATS and UREA for blossom thinning should be in the petal fall and full bloom stages for early and late harvest, respectively. Considering chemical injury, integrated harvesting and fruit size, however, it is appropriate to apply ATS at 1.5% in the petal fall stage to increase fruit productivity and quality in blueberry.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2001년도 춘계학술발표대회
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• pp.30-30
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• 2001

The culture of preantral follicles has important biotechnological implications through its potential to produce the large quantity of oocytes for embryo production, transgenesis research, conservation of rare breed, and a potential source of ovarian genetic material. The present study was conducted to establish the optimal conditions of in vitro culture for intact bovine preantral follicles; and to examine the developmental ability of oocytes derived from the in vitro-grown preantral follicles; and to investigate the effects of various concentrations of FSH and LH on these processes. Bovine preantral follicles (150 $\pm$ 1.2${\mu}{\textrm}{m}$), surrounded by theca cell, were isolated enzymetically and mechanically from ovarian cortical slides in Leibovitz L-15 medium containing 1 mg/$m\ell$ collagens and 0.2 mg/$m\ell$ DNase I and cultured for 25 days in the presence of different concentrations of bovine FSH and LH in $\alpha$MEM medium with insulin, transferrin, and selenite. The survival was tested by frypan Blue and Hematoxylin. The survival and growth rates of follicles were higher in FSH treatment groups than these in control (P<0.001), but there were no significant differences between the LH treatment groups and the control. In 25 days, the survival and growth rates of follicles in FSH and LH treatment group (50%, 300$\pm$1.0${\mu}{\textrm}{m}$) were higher than in FSH treatment group (40%, 244$\pm$0.5${\mu}{\textrm}{m}$) and the control group (25%, 160$\pm$ 1.0${\mu}{\textrm}{m}$). Fifty-five percent of healthy antral follicles were obtained, and 60% of the oocytes complete meiotic maturation to the metaphase II stage. Twenty-two percent of the mature oocytes underwent cleavage, and 9% developed to the blastocyst stage. In this study, in vitro-grown oocytes (111 $\pm$ $1.5mutextrm{m}$), under our culture conditions, were not equivalent in size to the in vivo-grown oocytes (130$\pm$1.3${\mu}{\textrm}{m}$). Therefore, these results suggest that bovine preantral follicles with intact theca cell can grow to the antral stage in 25days, and that oocytes from those follicles can acquire the meiotic competence and normally undergo fertilization and development to the blastocyst stage. However, the developmental capacity of in vitro-grown oocytes is presumably not comparable to those of the in vivo counterparts.

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.124-124
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• 2003

The successful development of embryos cloned by nuclear transfer (NT)have been dependent on a wide range of known factors including cell cycle of donor and recipient ooplast, oocyte quality, NT procedure and oocyte activation. The present study compared the development of cloned porcine embryos following different activation treatments. Cumulus-oocyte complexes (COCs) were aspirated from 26 mm follicles of slaughterhouse ovaries and cultured for 22 h in NCSU #23 medium supplemented with 10% porcine follicular fluid, 0.57 mM cysteine, 0.5 g/mL LH, 0.5 g/mL FSH and 10 ng/mL EGF. The COCs were further cultured for an additional 22 h in the same medium at $39{\cird}C$ in an atmosphere of 5% $CO_2$ in air, without hormonal supplements. Primary cultures of fibroblasts isolated from a female fetus on day 40 of gestation were established in DMEM + 15% FCS. For nuclear donation, cells at the 5th-6th passage were cultured in DMEM +0.5% FCS for 5 days in order to arrest the cells in G0/Gl. After enucleation, oocytes were reconstructed by transfer of donor cells and fusion with three DC pulses (1.4 KV/cm, 30 sec) in 0.28 M mannitol containing 0.01 mM $CaCl_2$ and 0.01 mM $MgCl_2$. Eggs were then divided into three treatment groups, control (without further treatment, Group 1), eggs cultured in 10 g/ml cycloheximide (CHX) for 5 h (Group 2), and eggs cultured in 1.9 mM 6-dimethylaminopurine (6-DMAP) for 5 h (Group 3). The eggs were then cultured in sets of 30 in 60 I drops of NCSU#23 supplemented with 4mg/ml BSA (essentially fatty acid free) until day 7 at $39{\circ}C$ in a humidified atmosphere of 5% $CO_2$. On day 4 the culture were fed by adding 20 I NCSU #23 supplemented with 10% FBS. Development rates into blastocysts were significantly higher (P<0.05) in Group 3 embryos compared to Group 1 controls ($27.6 \mu 2.7% vs. 20.1 \mu 4.1%$, respectively), but rates did not differ in Group 2 compared to control ($23.8 \mu 5.7%$). Total cell number in Group 3 blastocysts was however significantly higher (P<0.05) than in Groups 1 and 2 ($44.6 \mu 2.4 vs. 19.9 \mu 1.9 and 21.9 \mu 2.1$, respectively). These results suggest that 6-DMAP is more efficient than cycloheximide in the activation of electrically fused NT oocytes during in vitro production of cloned porcine embryos.

• Reproductive and Developmental Biology
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• 제28권2호
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• pp.77-82
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• 2004

5% $CO^2와 5% O^2$ 농도 조건 하에서 NCSU23 배양액에 aesculetin을 0, 1, 5 및 10 $\mug/ml$를 첨가한 구에서 상실배기 이상 발육된 체외배양 성적은 10 $\mu$ g 첨가구(35.7%)가 여타구(0 $\mu$g, 30.2% ; 1$\mu$g, 29.5% ; 5$\mu$g, 29.2%)보다 통계적으로 유의하게 높은 성적을 얻었다(P<0.05). NCSU 23 배양액에 taurine을 0, 2.5 및 5.0 mM을 첨가, 체외배양을 실시한 결과 배반포기 이상 발육된 체외발육 성적은 각각 2.8%, 2.2% 및 7.0%였으며, 상실배이상의 체외 발육성적은 26.1%, 26.9% 및 31.7%로서 taurine 5.0 mM 첨가가 체외수정란의 체외발육 성적이 유의적으로 높은 것으로 나타났다(P<0.05). NCSU 23 배앙액에 melatonin을 0, 1, 5 및 10nM을 첨가하여 체외배양을 실시한 결과, 배반포기까지 발육된 체외 발육성적은 17.8%, 26.1%, 20.0% 및 16.3%로서 melatonin 1nM 첨가구가 여타구에 비해 통계적으로 유의하게 높은 성적을 나타냈으며(P<0.05), 상실배기 이상 발육된 체외발육 성적에서는 melatonin 1nM 첨가구가 39.1%로서 대조구 33.3%, 5 nM 첨가구의 33.3% 및 10 nM 첨가구의 27.9%보다 높은 발육율을 나타냈다(P<0.05). 한편 배반포기 수정란의 세포수 조사에서는 melatonin 10 mM 첨가구가 유의하게 낮은 것으로 나타났다.

• Journal of Yeungnam Medical Science
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• 제12권1호
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• pp.124-134
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• 1995

Ham's F-10 기본 배양액과 이 배양액에 여러가지 농도의 EDTA와 태아제대혈청을 단독 또는 같이 혼합한 배양액을 얻어 각각의 배양액에서 5-10주된 백서를 이용하여 2 세포기 배아의 단계적 분할정도를 96시간 동안 관찰하였다. Ham's F-10 기본 배양액에 비해 태아제대혈청이나 EDTA $50{\mu}M$에서 $100{\mu}M$을 단독 또는 함께 첨가한 배양액에서 2 세포기의 배아의 상실배기 난할률이 매우 높았으며 (p<0.05), 포배기 난할률은 태아제대혈청과 EDTA $50{\mu}M$에서 $100{\mu}M$을 첨가한 배양액에서 유의하게 높았다(p<0.05). 체외수정실에서 흔히 사용되는 태아제대혈청을 첨가한 배양액과 비교시 태아제대혈청과 EDTA $100{\mu}M$을 첨가한 배양액에서 상실기 난할률이 유의하게 높았다(p<0.05). 태아제대혈청과 여러 농도의 EDTA를 첨가한 배양액과 EDTA만 첨가한 배양액의 비교에서 태아제대혈청과 EDTA $50{\mu}M$ 및 $100{\mu}M$을 첨가한 배양액에서 EDTA $200{\mu}M$만 첨가한 배양액에 비해 상실기 난할률이 매우 유의하게 높았고(p<0.05), 포배기 난할률은 태아제대혈청과 EDTA $100{\mu}M$을 첨가한 배양액이 EDTA $200{\mu}M$을 단독 또는 태아제대혈청과 함께 넣은 배양액에 비해 유의하게 높았다(p<0.05). 결론적으로 Ham's F-10 기본 배양액에 태아제대혈청과 적정 농도의 EDTA $50{\mu}M$ 및 $100{\mu}M$을 첨가한 배양액에서 초기 수정란의 분할이 우수함을 알 수 있고, 이는 수정란의 배양시 적절한 배양액을 선택할 수 있는 기초 자료로서 유용할 것으로 사료된다.

• 농업과학연구
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• 제41권4호
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• pp.361-367
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• 2014

Host plants of the Henosepilachna vigintioctomaculata are known as Solanaceae plants such as potato, tomato, eggplant and Lycium chinense. Henosepilachna vigintioctomaculata (Motschulsky) cause continuous damage from early June to mid-August in leaves of L. chinense under environmental-friendly management in Cheongyang, Chungnam. The developmental period of egg and larva of H. vigintioctomaculata were investigated. H. vigintioctomaculata were reared on L. chinense at several temperatures, for example, 15, 20, 25 and $30^{\circ}C$ in the laboratory. In addition, the control effect of 5 eco-friendly agricultural materials were examined. As results, hatching rate is the highest to 91% at $25^{\circ}C$. Egg periods were 10.8, 7.7, 5.1 and 3.7 days at each tested temperature, respectively. And the total developmental periods from egg to adult were 42.7, 26.3, 18.4 and 19.4 days at each tested temperature, respectively. Otherwise, their eclosion rates from pupa to adult were showed 58%, 77%, 85%, 65% at each tested temperature, respectively. As a result of the control effect, both adults and larvae of H. vigintioctomaculata were shown a high mortality to mixture with extract of Sophora flavescens, Chenopodium ambrosioides and Melia azedarach. Additional, larvae is shown high mortality to extract of Azadirachta indica and Cymbopogon nardus. Thus H. vigintioctomaculata might be controled by using plant extract of eco-friendly agricultural materials in due season.

• Reproductive and Developmental Biology
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• 제30권2호
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• pp.125-133
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• 2006

This study was conducted to detect the apoptosis incidence in blastocysts and to compare the abundance of Bax, Bcl2L1, VEGF and FGFR2 in in vitro fertilized (IVF), parthenogenetic (PAT) and nuclear transfer (NT) embryos. Oocytes matured for 40 hr were enucleated and reconstructed with confluenced fetal fibroblasts (FFs) derived from a ${\sim}45$ day fetus. Reconstructed eggs were then fused with 2 DC pulses (2.0 kV/cm, $30{\mu}sec$) and cultured with $7.5{\mu}g/ml$ cytochalasin B for 3 hr. Parthenotes (PAT) were produced with the same electric strength and culture for NT eggs. The embryos were cultured in NCSU-23 medium at $39^{\circ}C,\;5%\;CO_2,\;5%\l;O_2$ in air. In 3 runs, set of 10 embryos at the 4-cell to blastocyst stages were used to extract total RNA for analyzing the gene expression patterns of pro-apoptotic (Bax), anti-apoptotic (Bcl2L1), vasculogenesis (VEGF), implantation (FGFR2III) using real-time quantitative PCR. Cleavage and blastocyst rates were significantly higher (P<0.05) in IVF and PAT ($79.3{\pm}8.5\;and\;25.5{\pm}6.1,\;and\;85.0{\pm}6.4\;and\;38.6{\pm}5.5$, respectively)than NT counterparts ($65.1{\pm}5.2\;and\;15.6{\pm}3.0$, respectively). Significantly higher (P<0.05) total cells were observed in IVF controls and PAT ($34.7{\pm}5.8\;and\;38.1{\pm}4.1$) than NT embryos ($24.8{\pm}3.2$). Apoptosis index was significantly lower (P<0.05) in IVF than NT embryos. The Relative abundances (RA) of Bax and VEGF were significantly higher (P<0.05) at blastocyst stage in NT than IVF control. The RA of Bcl2L1 and FGFR2III were significantly higher (P<0.05) at blastocyst stage in IVF than NT. The present study observed the abnormal gene expressions in NT embryos at various developmental stages, suggesting certain clues to find out the cause of the low efficiency of NT to term.

• Reproductive and Developmental Biology
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• 제30권2호
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• pp.119-124
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• 2006

The present study compared the developmental potential of cloned porcine embryos with mesenchymal stem cells (MSCs), fetal fibroblasts (FFs) and cumulus cells (CCs) by assessing the cleavage and blastocyst rate, total cell number, inner cell mass (ICM) ratio and apoptosis. MSCs were isolated by ficoll gradients from femur of -6 month old female pig, and maintained for primary cultures. FFs from a female fetus at ${\sim}30$ day of gestation were established, and CCs were obtained from cumulus oocyte complexes (COCs) aspirated from $3{\sim}6$ mm follicles in diameter. Donor cells at $3{\sim}4$ passage were employed for nuclear transfer (NT). COCs were matured and fertilized in vitro(IVF) as control. Cleavage rate was significantly (P<0.05) higher in IVF than in NT embryos with MSCs, FFs and CCs ($82.7{\pm}8.9%\;vs\;70.6{\pm}5.4,\;68.7{\pm}5.1\;and\;63.4{\pm}5.6%$, respectively). However, blastocyst rates in IVF and NT embryos derived from MSCs ($24.5{\pm}2.8\;and\;20.4{\pm}8.3%$) did not differ, but were significantly (P<0.05) higher than NT derived from FFs and CCs ($10.6{\pm}2.7\;and\;9.8{\pm}2.1%$). Total cell number and the ratio of ICM to total cells among blastocysts cloned from MSCs ($35.4{\pm}5.2\;and\;0.40{\pm}0.09%$, respectively) were significantly (P<0.05) higher than those from FFs and CCs ($24.9{\pm}6.2%\;vs\;0.19{\pm}0.16,\;23.6{\pm}5.5\;and\;0.17{\pm}0.16%$, respectively). Proportions of TUNEL positive cells in NT embryos from FFs and CCs ($6.9{\pm}1.5\;and\;7.4{\pm}1.7%$, respectively) were significantly (P<0.05) higher than in MSCs ($4.8{\pm}1.4%$) and IVF ($2.3{\pm}0.9%$). The results demonstrate that MSCs have a greater potential as donor cells than FFs and CCs in achieving enhanced production of cloned porcine embryos.

• Asian-Australasian Journal of Animal Sciences
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• 제30권4호
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• pp.585-592
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• 2017

Objective: The present study investigates pre- and post-implantation developmental competence of nuclear-transferred porcine embryos derived from male and female fetal fibroblasts. Methods: Male and female fetal fibroblasts were transferred to in vitro-matured enucleated oocytes and in vitro and in vivo developmental competence of reconstructed embryos was investigated. And, a total of 6,789 female fibroblast nuclear-transferred embryos were surgically transferred into 41 surrogate gilts and 4,746 male fibroblast nuclear-transferred embryos were surgically transferred into 25 surrogate gilts. Results: The competence to develop into blastocysts was not significantly different between the sexes. The mean cell number of female and male cloned blastocysts obtained by in vivo culture ($143.8{\pm}10.5$ to $159.2{\pm}14.8$) was higher than that of in vitro culture of somatic cell nuclear transfer (SCNT) groups ($31.4{\pm}8.3$ to $33.4{\pm}11.1$). After embryo transfer, 5 pregnant gilts from each treatment delivered 15 female and 22 male piglets. The average birth weight of the cloned piglets, gestation length, and the postnatal survival rates were not significantly different (p<0.05) between sexes. Conclusion: The present study found that the sex difference of the nuclear donor does not affect the developmental rate of porcine SCNT embryos. Furthermore, postnatal survivability of the cloned piglets was not affected by the sex of the donor cell.

• Toxicological Research
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• 제21권4호
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• pp.325-332
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• 2005

The developmental toxicity of water extract of licorice (Glycyrrhiza glabra) was evaluated in rats. Licorice extract (500, 1,000 or 2,000 mg/kg) was dissolved in drinking water and orally administered to male rats from 9 weeks before mating to the day of copulation, and to females from 2 weeks before mating to gestational day 19. On gestational day 20, the animals were sacrificed for Cesarian section, and maternal and fetal abnormalities were examined. Licorice extract neither induce clinical signs, nor affect the body weight gain, feed and water intake, estrous cycle, copulation and fertility rates, blood $17\beta-estradiol$ level and organ weights of dams. Also, the implantation and development including body weights, absorption and death of embryos and fetuses were not influenced by in utero exposure to licorice. In addition, there were no increases in external, visceral and skeletal abnormalities of fetuses. Taken together, it is suggested that no observed adverse effect level of licorice extract is higher than 2,000 mg/kg, and that long-term in utero exposure to licorice might not cause developmental toxicities of embryos and fetuses.