The aim of this present study was to investigate the impact of different seeding rate and nitrogen fertilizing levels on the seed yield and feed value of oats(Avena sativa L.) grown in Gyeongbuk area for two years. The experiment was arranged in split plot design with 3 main plots(100, 130 and 160 kg of seed/ha) and 4 subplots(0, 50, 70 and 90 kg N/ha), with 3 replicates. Heading, flowering, and maturing dates of oats sown in spring 2017, delayed by two days compared to that of spring 2016, and the plant height of spring 2017 were significantly shorter than that of spring 2016(18.1 ~ 23.4 cm). In addition, the highest number of stems and number of panicles according to different seeding rate and nitrogen fertilizing levels were achieved with the seeding rate of 160 kg/ha and 90 kg of N/ha in 2016 and 2017, respectively. In case of seed yield as affected by different seeding rate, the highest seed yield was achieved with a seeding rate of 130 kg/ha(p<0.05), and based on nitrogen fertilizing levels, the highest yield was obtained in 50 kg of N/ha compared to others. The crude fiber(CF), neutral detergent fiber(NDF) and total digestible nutrients(TDN) of oats cultivated and harvested in spring 2016 and 2017 according to different sowing rate were the highest in the seeding rate of 130 kg/ha. The crude protein(CP) content and total digestible nutrients(TDN) of 2016-2017 as influenced by nitrogen fertilizer levels were the highest in the nitrogen fertilizer level of 90 and 50 kg N/ha, respectively. In conclusion, the proper seeding rate and the optimal nitrogen fertilizing level in Gyeongju, Gyeongbuk province were considered to be the most appropriate in 130 kg/ha and 50 kg of N/ha, respectively.

목적: 안경렌즈의 주변부를 통해서 주시할 때 발생하는 굴절의 변화를 살펴보았다. 방법: 렌즈의 주변부를 통해 봤을 때 굴절력의 변화를 측정하기 위해 렌즈미터의 렌즈 받침부(lens support)로부터 25mm아래에 있는 회전축을 중심으로 주시각도만큼 렌즈가 기울어진 상태에서 렌즈미터로 굴절력을 측정하였으며, 광학중심부와 주변부에서 측정한 굴절력과 비교하였다. 또한 주시각도에 따른 두께의 변화와 정점간 거리의 변화가 굴절에 미치는 영향을 살펴보았다. 결과: 주시각도가 커짐에 따라 시선이 지나가는 렌즈의 두께는 증가하지만 교정굴절력에 큰 영향을 미칠 정도는 아니었다. 주시각도가 증가하면 정점간 거리도 증가하게 되며 추가 (-)굴절력이 필요하다. 주시각도가 30ﾟ이내일 때 추가 굴절력은 –0.1D이하이다. 주시각도가 증가할 때 최소굴절력(구면굴절력)은 기준굴절력과 대체로 큰 차이가 없었다. 원주굴절력은 주시각도 10ﾟ정도까지는 거의 발생되지 않았으나 주시각도가 증가함에 따라 증가하는 경향을 보였다. 결론: 주변시에서 비점수차 등의 수차에 의한 굴절력의 변화는 렌즈의 사용 환경과 취급에서 고려되어야 할 것이다.

We performed a survey for flavivirus infection and distribution of Aedes albopictus that known as Zika and Dengue virus vector using black–light trap and BG-sentinel trap around urban area in Korea. Mosquitoes were collected in 27 cities during March to November (twice a month) year 2016. Total numbers of mosquitoes collected 102,102 including 19 species 8 genera during collecting period. Total 21,467 Ae. albopictus was collected that 20,961(24.3%) by BG-sentinel trap and 506 (3.2%) by Black-light trap in urban area. Trap index(trap/night) of Ae. albopictus was showed highest in Hamyang (TI:992.3) and lowest in Taebaek (TI:0.3) there was only collected by Black-light trap. A total of 894 pools from all collecting Ae. albopictus were performed a Flavivirus detection. Flavivirus was not detected during study period. This study may provide basic information for surveillance of imported diseases (include Zika virus) and vectors in Korea.

Bacillus thuringiensis (Bt) produces a variety of insecticidal crystal proteins and widely used as one of the most successful biological control agents. Recently, studies that introduce cry genes into crops to create pest resistance have made much progress, and the total area of land planted with Bt crops has increased substantially. In this study, pest resistance of 8 transgenic Bt rice events with a synthetic cry1Ac gene linked to rice rbcS-tp sequence were assessed under laboratory conditions. Bioassays were performed against Cnaphalocrocis medinalis, which is a significant pest of rice in Asia. C. medinalis larvae were shown to be susceptible to all eight events, even though there were differences between the causes of death. The results differed between developmental stages of the larvae, despite the fact that all 8 events led to high mortalities. These results may be a significant foundation for the evaluation of improved transgenic Bt rice.

Insect growth regulators (IGRs) are attractive pest control agents due to their high target specificity and relative safety to the environment. Recently, plants have been shown to synthesize IGRs that affect the insect juvenile hormone (JH) as a part of their defense mechanisms. We identified several JH agonists (JHAs) and antagonists (JHANs) from plant essential oil compounds using a yeast two-hybrid system transformed with the Aedes aegypti JH receptor as a reporter system. They showed high mosquitocidal activities with relatively low LC50 values and caused retardation of ovarian development in female mosquitoes. While the JHAs increased the expression of JH-induced gene, the JHANs caused reduction in the expression of the same gene. The compounds identified in this study could provide insights on the plant-insect interactions and may be useful for the development of novel IGR insecticides.

Insect growth regulators (IGRs) are compounds that induce developmental anomalies such as premature molting or supernumerary larval stages. IGRs can be divided into 3 groups based on their mode of action, one of which is known as the juvenile hormone agonists (JHAs). Previously, we have developed a novel screening method which can identify juvenile hormone antagonists (JHANs) using a yeast-two hybrid system incorporating Aedes aegypti juvenile hormone receptor complex proteins (MET and FISC). It has been reported that plants may use IGRs in their defenses against insect herbivores. In this study, 171 plant essential oil samples were screened using the yeast-two hybrid system in order to identify JHAs and/or JHANs. Eight out of 171 samples, 4 JHA and 4 JHAN candidates, were selected and their insecticidal activities were investigated against A. aegypti larvae. They showed high levels of insecticidal activities, with LC50 values ranging from 11.2~21.4 ug/ml. These results indicate that plants do use JHAs and/or JHANs as a part of their defenses against insect herbivores. Also, JHAs and JHANs identified in this study could be exploited as effective biological control agents.

Insect growth regulators (IGRs) are insecticides that disrupt the normal development of target insects by inducing symptoms such as premature molting or supernumerary larval stages. IGRs are categorized into three types based on their mode of action. One of the them is classified as juvenile hormone agonists (JHAs). Recently, we developed a yeast-two hybrid system that can identify potential juvenile hormone antagonist (JHAN) candidates using Aedes aegypti juvenile hormone receptor complex proteins, known as MET and FISC. In order to identify novel JHAN compounds, approximately 8,700 basic chemical compounds were screened using the yeast-two hybrid system. Among them, 35 compounds were first selected based on consistency of JHAN　activity, and their insecticidal activities were investigated against A. aegypti larvae. These compounds showed insecticidal activities about 1.7~3 times higher than that of pyriproxifen, which is a well known JHA insecticide. These results suggested that these JHANs can be used as effective JHAN insecticides.

Insect Growth Regulators (IGRs) are insecticides that disrupt the normal development of target insects by inducing symptoms such as premature molting or supernumerary larval stages. Juvenile hormone systems become the targets of two types of IGRs: the Juvenile Hormone Agonists (JHAs) and Juvenile Hormone Antagonists (JHANs). Pyriproxyfen is one of the chemical compounds widely used as JHA to control many kinds of insects while Kanakugiol is a plant-extracted compound which acts as JHAN. The small brown planthopper, Laodelphax striatellus, is one of the most serious pest insects of rice plants because it can transmit the rice stripe virus which often causes significant reduction of yield in the field. In order to analyze the differential gene expressions of L. striatellus upon JHA and JHAN treatment by using next generation sequencing technique, we sprayed Pyriproxyfen and Kanakugiol on 4th instar nymphs of L. striatellus respectively, and extracted total RNA for RNA-seq. The quality-filtered Illumina sequence reads of the control, JHA, and JHAN treated samples were mapped to the reference gene sequences by using the Bowtie2 software. Then the results of mapping by Bowtie2 were analyzed by eXpress software to quantity the differential gene expression.

Recently, Bacillus thuringiensis (Bt) cry genes encoding insecticidal Cry proteins have been widely applied for the construction of transgenic crops resistant to insect pests. This study aimed to construct novel mutant cry1Ac genes for genetically modified crops with enhanced insecticidal activities. Using multi-site directed mutagenesis, 34 mutant cry1Ac genes were synthesized and converted at 24 amino acid residues, located on domain I (8 residues) and domain II (16 residues). These mutant genes were expressed as a fusion protein with polyhedrin using the baculovirus expression system. The expressed proteins were occluded into polyhedra and activated stably to 65 kDa by trypsin. Among these, Mut-N04, N06, and N16 showed high levels of insecticidal activites against larvae of Plutella xylostella, Spodoptera exigua, and Ostrinia furnacalis. Mut-N16, which showed the highest insecticidal activity, is expected to be a desirable cry gene for introduction into transgenic crops. This study could provide useful means to construct mutant cry genes with improved insecticidal activities and expanded host spectrum for transgenic crops.

The recent development in genetic assisted selection (combining traditional- and genome assisted selection method) and reproduction technologies will allow multiplying elite cow in Hanwoo small farm. This review describes the new context and corresponding needs for genome assisted selection schemes and how reproductive technologies can be incorporated to get more genetic gain for cow genetic improvement in Hanwoo. New improved massive phenotypes and pedigree information are being generated from commercial farm sector and these are allowing to do genetic evaluation using BLUP to get elite cows in Korea. Moreover cattle genome information can now be incorporated into breeding program. In this context, this review will discuss about combining the reproductive techniques (Multiple Ovulation Embryo Transfer; MOET) and genome assisted selection method to get more genetic gain in Hanwoo breeding program. Finally, how these technologies can be used for multiplication of elite cow in small farm was discussed.

Artificial insemination (AI) has been performed widely in swine industry using fresh liquid sperm instead of frozen type of sperm. However fresh sperm are not able to preserve more than three days with optimal motility and other sperm parameters for the successful fertilization, since in vitro stored sperm has an oxidative stress that resulted increase of abnormality and acrosome reation. To overcome these major problems, novel preservative formulation is needed to neutralize the oxidative stress and to provide suitable physiological environment for sperm in in vitro. In this study, naturally derived substances such as Poncirus trifoliate (Trifoliate orange), Garcinia mangostana (Mangosteen), pig placenta and testis extracts were tested as sperm preservative agents. Placenta extracts (PE), trifoliate orange extracts (TOE), testes extracts (TE) and mangosteen extracts (ME) were applied to analyze specific parameters for sperm motion characteristics individually and combinatorial. Each individual extract treatment can accelerate the sperm motility but noticeably TOE, TE and ME treatments exhibited the considerable and significant preservation of sperm motility. PE, TE and ME showed a significant (p<0.05) increase in ALH after one week. Further we evaluated the five different combinations of these extracts on sperm motility and its motion characteristics. Surprisingly even after one week ME, TOE and TE combination significantly preserved the sperm motility about 75%. It is noteworthy that unlike individual extract treatment, combination of ME, TOE and TE simultaneously protect the sperm motility and its motion characteristics. Taken together these data conclude that addition of ME, TOE and TE can be effective for preservation of pig sperm.