• Journal of Plant Biotechnology
• /
• v.44 no.1
• /
• pp.49-55
• /
• 2017

We investigated the callus induction and plant regeneration ability of 16 maize genotypes, including the Korean inbred lines, using 9 to 15 day-old immature zygotic embryos from maize grown in pots and from field cultures. Immature zygotic embryos placed on MS medium supplemented with L-proline 0.7 g/L, MES 0.5 g/L, Dicamba 1.5 mg/L, 2,4-D 0.5 mg/L, $AgNO_3$ 4 mg/L, and sucrose 20 g/L, showed the highest frequency of callus induction. The highest number of shoots regenerated when the embryogenic callus were transferred to MS medium supplemented with 5 mg/L zeatin. The root formation was observed when shoots were grown on MS medium supplemented with 0.2 mg/L indole-3-butyric acid (IBA). Additionally, under the same culture conditions, immature zygotic embryos from maize grown in the field also had a high frequency of plant regeneration. Except one genotype, 15 genotypes showed callus induction and shoot regeneration. Among the 16 genotypes tested, H99, B98, HW3, and B73 yielded the best plant regeneration. H99 showed maximum shoot formation from the primary embryogenic callus. The results suggest that genotypes and growth conditions of the maize plant plays very important roles for enhancing the embryogenesis competence of immature zygotic embryos. The successful regeneration from immature zygotic embryos of maize inbred lines provides a basis for molecular breeding of new cultivars by genetic transformation.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.39 no.2
• /
• pp.45-53
• /
• 2019

The popularity of keeping stag beetles (Dorcus titanus castanicolor Motschulsky 1861, Coleoptera: Lucanidae) as pets has increased. Consistent with the rise in the number of insect farms using these beetles, the number of contaminated or diseased D. titanus castanicolor has also increased. This investigation was conducted to analyze the cause of D. titanus castanicolor disease. The contaminated larvae of D. titanus castanicolor showed Allomyrina nudivirus infection symptoms similar to those of Allomyrina nudivirus infection. However, the disease carried by of D. titanus castanicolor is not derived from the virus infecting Allomyrina, as determined by PCR. Our study revealed that the major gut microbes of infectious D. titanus castanicolor belonged to the phylum Proteobacteria, and specifically, Pseudomonas knackmussi (Symptom 1 - 39.62% to Symptom 2 - 41.50% to Symptom 3 - 76.76% as the disease progressed severely) and Citrobacter koseri (Symptom 1 - 1.48% to Symptom 2 - 6.04% to Symptom 3 - 6.16% as the disease progressed severely) were detected. Additionally, a high proportion of larvae from the uninfected group were found to harbor bacteria belonging to the phylum Firmicutes (72%). However, as the disease progressed severely in these beetles, the proportion of Firmicutes decreased (Symptom 1 - 72.03% to Symptom 2 - 44.7% to Symptom 3 - 26.3%). These findings imply that colonization by Firmicutes was inversely proportional to Proteobacteria colonization in the gut. This was found to be true for both the normal and disease conditions of D. titanus castanicolor. In this study, we examined the distribution of intestinal microbial communities in normal and contaminated larvae. We observed a correlation between these contaminated microbes and the overall health of the beetle, and our findings suggest that there may be a link between disease progression and the gut microbiome.

• Journal of Korean Society of Rural Planning
• /
• v.23 no.2
• /
• pp.55-65
• /
• 2017

This study is to estimate the circuity factors which can be used to assess for public facilities accessibility and analyze traffic in the area. We set the range of the administrative districts by Si Gun Gu unit and Eup Myeon Dong unit (more subdivided unit than Si Gun Gu unit). The average circuity factor in Si Gun Gu unit is 1.364 (maximum 2.953 and minimum 1.711). The region indicated the highest value of circuity factor is wando-gun in jeollanam-do, which area consists of 4 island and is connected to the bridges. Having to use the bridges for using public facilities hinders its accessibility. In the case of Eup Myeon Dong unit, the average circuity factor is 1.353 (maximum 2.950 and minimum 1.154). The region indicated the highest value of circuity factor is buksan-myeon in chuncheon-si, Gangwon-do. This region also has to use bridges for using public facilities because there is the largest lake, called Soyangho. This circuity factor is used to analyze the location of public facilities and assess vulnerability of accessibility. And also the factor can be applied to some policies, such as rural public service planning based on spatial big data.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.3 no.2
• /
• pp.141-147
• /
• 2001

To study the ecological characteristics of the Korean native firefly, Luciola lateralis, development and life history of L. lateralis were investigated throughout the indoor rearing. Average size of egg with an oval shape was 0.51${\times}$0.56 mm and an egg period of L. tateralis was approximately 25.8 days. The larvae were pupated at the 5$^{th}$ instar and the body length of the matured larvae was 15.8mm. The total periods of larval stage to the end of the $5^{th}$ instar were approximately 271.7 days. Pupae formed soil cocoon and average pupal period was approximately 28.7 days. Average number of eggs oviposited by a female was approximately 97. The body size of female in the pupa and adult were larger that of male.

• Journal of Korean Society of Rural Planning
• /
• v.29 no.4
• /
• pp.55-67
• /
• 2023

This study investigated the correlation between impervious surface area rate(ISAR) and various urbanization indicators at the si-gun administrative level. For the years 2017 and 2021, we built correlation matrices to examine the relationships between ISAR and eight urbanization indicators, including total population, working-age population, residential power consumption, non-agricultural power consumption, paved road length, permitted development area, numbers of registered vehicles, and cadastral 'Dae' parcel area. Additionally, K-means clustering was employed to classify the 229 si-guns based on the ISAR change patterns. The analysis revealed a significant positive correlation between ISAR and urbanization indicators for both years studied. However, the interannual comparison showed a noticeably weaker correlation between changes in ISAR and urbanization indicators from 2017 to 2021. The K-means analysis also showed that si-guns with higher ISAR values, typically urban areas, demonstrated a weaker correlation, while the cluster consisting mostly of rural areas with lower ISAR displayed stronger correlations. These results suggested that ISAR should be a significant factor for consideration in sustainable rural planning and development strategies.

• Korean Journal of Agricultural Science
• /
• v.36 no.1
• /
• pp.57-61
• /
• 2009

The invasive pest Brontispa longissima(Coleoptera: Chrysomelidae), native to Indonesia and Papua New Guinea, has extended its distribution to Australia, Asia and Pacific islands and caused serious leaf damages of the coconut palm Cocos nuciferain the invaded regions. Although biological control using parasitic wasps has successfully reduced population density and leaf damage levels, this pest and its natural enemies have not been efficiently producedin conventional methods using young leaves of C. nucifera. In the present study, we examined suitability of plants easily available in Thailand and Japan for mass rearing of this pest to develop effective mass rearing system of this pest. Mature, green leaves of the palms were also suitable for immature development and adult reproduction of this pest. Since mature leaves of C. nucifera are more abundant and less contaminated with fungus than the unopened leaf buds, mature leaves could be a promising plant diet for mass rearing of B. longissima. Ornamental palms such as Hyophorbe lagenicaulis and Washingtonia filifera were also suitable for immature development and reproduction of B. longissima. Away from palms, the cattail Typha spp. can sustain immature development and adult reproduction of B. longissima. In the area where C. nucifera is rare or not available, W. filifera or Typha spp. would be good food plants for mass rearing of this pest.

• The Journal of the Korea Contents Association
• /
• v.21 no.5
• /
• pp.548-560
• /
• 2021

This study estimates the amount of willingness to pay of the general public by applying the contingent value method to the Korea Program for International cooperation in Agricultural technology(KOPIA), a representative project of the Rural Development Administration. Prior to measuring the amount of willingness to pay for the KOPIA project, a survey of the perception of agriculture and rural areas and respondents' basic perception of public development assistance showed a positive perception of official development assistance in general. In particular, many respondents said that aid from the international community in the past contributed to Korea's economic and social development along with the importance of the international community helping the poor in underdeveloped countries. As a result of estimating the acceptance probability regression model by including the public awareness as a variable, the higher the income of the respondents and the more positive the perception of public development aid, the higher the amount of willingness to pay. The average annual payment amount per household derived from the acceptance probability regression model was estimated to be about 30,729 won.Based on the results of this analysis, several policy implications related to the public development aid policy of Korea were presented.

• Journal of the Korean association of regional geographers
• /
• v.10 no.2
• /
• pp.479-496
• /
• 2004

This study attempts to examine Egyptian agricultural development with regard to the social and political changes in the Egypt, and tries to explore the patterns of major crops and those spatial distribution nowadays. Also, land reclamation processes and farming activities are explained. Agricultural development in Egypt has been considerably affected by historical international trade, and those crops such as cotton and sugar cane have been especially protected and controlled as strategic crops by the Egyptian governments. The issues of land ownership have been varied with political environments by periods, but the controls to the strategic crops have been consistently maintained to a degree though some variations. since the 1990s, national liberalization programs also caused to change the agricultural policies which have affected the adjustments of crop production and land use. Spatial distribution of major crops and farming activities are examined in relation to natural environments by Delta, Middle and Upper Egypt, desert areas. The projects of land reclamation after 1952 are evaluated with the effects of government intervention, and the actors in use of the reclaimed lands are investigated.

• International journal of advanced smart convergence
• /
• v.9 no.1
• /
• pp.215-221
• /
• 2020

The paradigm of agriculture is also changing to address the problem of food shortages due to the increase of the world population, climate conditions that are increasingly subtropical, and labor shortages in rural areas due to aging population. With the development of Information Communication Technology (ICT), our daily lives are changing rapidly and heralds a major change in agricultural management. In a hyper-connected society, the introduction of high-tech into traditional Agriculture of the past is absolutely necessary. In the development process of Agriculture, the first generation produced by hand, the second generation applied mechanization, and the third generation introduced automation. The fourth generation is the current ICT operation and the fifth generation is artificial intelligence. This paper investigated Smart Farm that increases productivity through convergence of Agriculture and ICT, such as smart greenhouse, smart orchard and smart Livestock. With the development of sustainable food production methods in full swing to meet growing food demand, Smart Farming is emerging as the solution. In overseas cases, the Netherlands Smart Farm, the world's second-largest exporter of agricultural products, was surveyed. Agricultural automation using Smart Farms allows producers to harvest agricultural products in an accurate and predictable manner. It is time for the development of technology in Agriculture, which benchmarked cases of excellence abroad. Because ICT requires an understanding of Internet of Things (IoT), big data and artificial intelligence as predicting the future, we want to address the status of theory and actual Agriculture and propose future development measures. We hope that the study of the paper will solve the growing food problem of the world population and help the high productivity of Agriculture and smart strategies of sustainable Agriculture.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.5 no.1
• /
• pp.73-77
• /
• 2002

The Sec61 trimeric complex ($\alpha$,$\beta$, and ${\gamma}$ subunits) is one of the Sec-complex responsible for post-translational protein translocation across the endoplasmic reticulum membrane in diverse organisms. In this study, a cDNA encoding the Sec61p ${\gamma}$ subunit homologue was isolated from the cDNA library of the mole cricket, Gryllotalpa orientalis. Sequence analysis of a 442-bp cDNA clone showed it to contain an open reading frame of 68 amino acid residues consisted of 204-bp. The homologues of the gene were found in the GenBank database in a diverse organism including insect, mammals, fungi, and plants. The deduced amino acid sequence of Sec61p ${\gamma}$ subunit homologue of the mole cricket showed the highest homology to the gene of the singly known insect, Drosophila melanogester (93% identity), and the least homology to that of the baker's yeast, Saccharomyces cerevisiae (37.2%). Phylogenetic analysis also confirmed a close relationship between the insect Sec61p ${\gamma}$ subunit homologues of G. orientalis and D. melanogester. Hydropathy analysis of the cricket mole and published other data suggested that the hydrophobic segment close to C-terminus is predicted to be the putative membrane anchor, Multiple alignment of the Sec61p ${\gamma}$ subunit homologue among several organisms showed the presence of several conserved domains including the conserved proline at position 28.