• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.6
• /
• pp.3797-3806
• /
• 2015

A population decline in rural area is correlated with the number of household, with agricultural workers, as a result, affects the farming income. Agricultural population is a foundation of agriculture structure. Agricultural population decline influences agricultural policies to be implemented for the future and there is concern about slowdown in productivity. The purpose of this study is to build the ability to use the model and conduct applied analyses of various kinds and to make rational agricultural policies by forecasting and analyzing agricultural population change. Unlike previous studies, which have some assumptions about the giving-up farming rate (GFR) of the key points on the agricultural population model or, After estimating only one equation with respect to the total population, and then distribute by sex and age. This study was conducted to investigate the reactions are different from the farmhouse, gender, age by estimating giving-up farming rate (GFR) equations each gender & age. Through this research, we can find that Farm Population changes of the simulation can be performed for a variety of agricultural policy in conjunction with existing agricultural simulation models as well.

• Entomological Research
• /
• v.48 no.6
• /
• pp.559-566
• /
• 2018

In Korea, the centipede called "Wang-ji-ne" or "O-gong" is used as an important medicinal resource. This centipede has been known as Scolopendra subspinipes mutilans Koch 1878. Recent studies have assessed its taxonomic treatment in several geographical populations from China, Japan and Taiwan, but not Korea. We therefore attempted to assess exact species status for the Korean population of this subspecies using both morphological and DNA barcode methods. The result inferred from DNA barcoding showed that the Korean population is S. mutilans explicitly separated from S. subspinipes. Within S. mutilans, the Korean population is morphologically identical and genetically closer to the Chinese population rather than island populations of Japan and Taiwan. Particularly, the mainland populations from Korea and China share six haplotypes from 17 despite being far apart geographically.

• Animal Bioscience
• /
• v.35 no.12
• /
• pp.1839-1849
• /
• 2022

Objective: The study aims to uncover the genetic diversity and unique genetic structure of the Min pig conserved population, divide the nucleus conservation population, and construct the molecular pedigree. Methods: We used KPS Porcine Breeding Chip v1 50K for SNP detection of 94 samples (31♂, 63♀) in the Min pig conserved population from Lanxi breeding Farm. Results: The polymorphic marker ratio (PN), the observed heterozygosity (Ho), and the expected heterozygosity (He) were 0.663, 0.335, and 0.330, respectively. The pedigree-based inbreeding coefficients (F_PED) was significantly different from those estimated from runs of homozygosity (F_ROH) and single nucleotide polymorphism (F_SNP) based on genome. The Pearson correlation coefficient between F_ROH and F_SNP was significant (p<0.05). The effective population content (Ne) showed a continuously decreasing trend. The rate of decline was the slowest from 200 to 50 generations ago (r = 0.95), then accelerated slightly from 50 to 5 generations ago (1.40

• Asian-Australasian Journal of Animal Sciences
• /
• v.24 no.8
• /
• pp.1048-1052
• /
• 2011

The Chinese Holstein cattle breed, an introduced breed in China, has been crossbred with native cattle breeds. We hypothesised that the Chinese Holstein local population in Beijing share haplotypes with native Asian cattle breeds, the result of a sudden population expansion in the recent past. We also hypothesised that crossbreeding and population expansion left traces that shaped the genetic makeup of the breed. Evaluation of this was performed by mitochondrial DNA (mtDNA) sequence analysis of Chinese Holstein cattle from Beijing (n = 41) and a comparison of them with the published mtDNA sequences (n = 293) of 14 Asian breeds with an emphasis on Chinese native cattle breeds. Three shared common haplotypes between Chinese Holstein cattle and native Asian cattle were found. Moreover, a high level of haplotype diversity in Chinese Holstein cattle (h = 0.9557) and low nucleotide diversity (${\pi}$ = 0.0052) was found, indicating a past population bottleneck followed by rapid population growth. These findings are supported by the significantly negative deviation of Tajima's D (-1.82085), the star-like pattern of dominant haplotypes and the pairwise mismatch distribution analysis, which showed a unimodal pattern.

• Korean Journal of Agricultural Science
• /
• v.50 no.4
• /
• pp.829-840
• /
• 2023

Various chemical pesticides are used to control diamondback moths, Plutella xylostella, which are agricultural pests that occur in cruciferous crops worldwide and cause economic losses. However, due to pesticide misuse, resistance to P. xylostella is consistently reported domestically and internationally. Therefore, we aimed to monitor and map regional resistance to devise efficient and economical control methods for P. xylostella in Korea. This study selected eight highly used insecticides among those registered against P. xylostella. P. xylostella were collected from three cities in the Gyeonggi and Yeongnam Provinces to evaluate insecticide resistance. As a result of experiments with populations collected from Yeoju, Gyeonggi Province, resistance ratios were 114.88, 54.75, 119.00, and 64.00 times higher than the susceptible population with methoxyfenozide, indoxacarb, cyantraniliprole, and fluxametamide, respectively. The resistance ratios of the Yongin population in Gyeonggi Province were 166.33 times with cyantraniliprole and 195.25 times with fluxametamide higher than the susceptible population. The Pocheon population in Gyeonggi Province showed a resistance ratio 283.23 times higher than methoxyfenozide. As a result of experiments with populations collected from Gimhae and Sangju, Yeongnam Province, the resistance ratios of the Gimhae population were 80.97, 138.00, and 89.50 times higher than the susceptible population with methoxyfenozide, cyantraniliprole, and fluxametamide, respectively. Meanwhile, the resistance ratios of the Sangju population were 85.83, 224.67, and 303.25 times higher than the susceptible population with methoxyfenozide, cyantraniliprole, and fluxametamide, respectively. The Yeongnam Province Tongyeong population showed a resistance ratio 367.28 times higher to methoxyfenozide.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.48 no.2
• /
• pp.96-102
• /
• 2003

This study was conducted to determine the effects of two plant populations (28 and 14 plants per $m^2$) and two toppings in conventional plant population (28 plants per $m^2$) on soybean (Glycine max L. cv. Pungsannamulkong) cultivated in the paddy field. The two topping time were taken at 6$^{th}$ to 7$^{th}$ and 8$^{th}$ to 9$^{th}$ trifoliolate leaf stages in the conventional plant population. Experimental design for growth data was a randomized complete block with three replications, and samples were taken at R1 (July 31), R3 (August 19), R5 (September 2) and R7 (September 23) growth stages. The branch number of soybean was relatively higher in the low plant population (14 plants per $m^2$) and with the topping at the 6$^{th}$ to 7$^{th}$ leaf stage, in the conventional plant population (28 plants per $m^2$), and with topping at the 8$^{th}$ to 9$^{th}$ trifoliolate leaf stage in descending order. The highest average branch length of soybean was observed in the low population and the longest branch length was observed from the soybean with topping at the 6$^{th}$ to 7$^{th}$ leaf stage. The leaf number per plant was decreased in order of in the low population, with the topping at 6$^{th}$ to 7$^{th}$ trifoliolate leaf stage, with the topping at 8$^{th}$ to 9$^{th}$ trifoliolate leaf stage, and in the conventional population. The leaf area was high in the low population and with topping at 6$^{th}$ to 7$^{th}$ trifoliolate leaf stage and was relatively low in the conventional population and with the topping at 8$^{th}$ to 9$^{th}$ trifoliolate leaf stage in soybean. The dry weight of leaves and branches was high in the low population and with the topping at 6$^{th}$ to 7$^{th}$ trifoliolate leaf stage and was relatively low in the conventional population and with topping at 8$^{th}$ to 9$^{th}$ trifoliolate leaf stage. The leaf number per plant was high in the low population and with topping at 6$^{th}$ to 7$^{th}$ trifoliolate leaf stage and was relatively low in the conventional population and with topping at 8$^{th}$ to 9$^{th}$ trifoliolate leaf stage. The grain yield per 10a was high with the topping at 6$^{th}$ to 7$^{th}$ trifoliolate leaf stage.

• Korean Journal of Environmental Agriculture
• /
• v.20 no.5
• /
• pp.325-329
• /
• 2001

Soil enzyme and microbial activities are affected by fertilizer and compost applications and can be used as sensitive indicators of ecological stability. Microbial population and soil enzymes viz., dehydrogenase, urease, acid phosphatase and aryl-sulphatase were determined in the long-term fertilizer and compost applied paddy soil. Soil samples were collected from the four treatments (control, compost, NPK and compost+NPK). Long-term NPK+compost application significantly increased activities of urease, dehydrogenase and acid phosphatase than all other treatments. The compost application enhanced activities of urease, dehydrogenase and acid phosphatase than the NPK application. However, arylsulfatase activity was not significantly different between compost and fertilizer application. The highest microbial population was recorded in the NPK+compost treatment. The compost application also resulted in higher microbial population than the NPK application. The above results indicate that ecological stability could be maintained by application of compost alone or with NPK.

• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.3
• /
• pp.302-306
• /
• 2001

This study was carried out to construct mapping population and to evaluate the methods involved, including polymorphic DNA marker system and appropriate statistical analysis. As an initial step to establish chicken genome mapping project, White Leghorn (WL) and Korean Ogol chicken (KOC) were used for generating backcross population. From 8 initial parents, total 280 backcross progenies were obtained and 40 were used for genotyping and linkage analysis. For development of novel polymorphic markers for KOC, Random Amplified Polymorphic DNA (RAPD) markers specific for this chicken line were generated. Also included in this study were six microsatellite markers from East Lansing map as reference loci. For segregation analysis, 15 RAPD markers and 6 microsatellites were used to genotype the backcross population. Among the RAPD markers that we developed, 2 pairs of markers were identified to be linked and another 4 RAPD markers showed linkage with microsatellites of known map. In summary, this study showed that our backcross population generated from the mating of KOC to WL serves as a valuable genetic resource for genotyping. Furthermore, RAPD markers are proved to be valuable in linkage mapping analysis.

• Journal of Korean Society of Rural Planning
• /
• v.19 no.4
• /
• pp.203-212
• /
• 2013

The aging of farm households has caused serious problems such as productivity slowdown and aggravated income polarization in South Korea. Urban-to-rural migration has been recently suggested as a measure to attenuate the aging of rural population and other related problems. The inflow of migrants for farming can have a substantial effect on agriculture and rural communities while the natural adjustment of rural population caused by birth and death is slow. This paper forecasts population distribution of different provinces using the Origin-Destination (OD) analysis, taking into account both the size and directions of migration. In the analysis, nodes where the migration takes place are divided by the industrial sectors (agriculture and non-agriculture), regions, and ages. The results of a ten-year forecast shows that the aging of total population in most provinces will be intensified, but the portion of people over sixty will decrease in the agricultural sector. This finding implies that migration into rural areas, when occurring by a large extent, can mitigate the aging process and attendant problems.

• Journal of agricultural medicine and community health
• /
• v.33 no.1
• /
• pp.82-89
• /
• 2008

Objective:　We compared the prevalence of injury and poisoning in the agricultural and fishery population with that of the general population.Methods: The national health insurance data and agricultufor this study. The age-adjusted standardized morbidity ratio was used to compare the prevalence of all injuries and poisonings of the agricultural and fishery population with that of the general population for the year 2002, as well as the prevalence of certain injuries and poisonings common to the agricultural and fishery population. The age-adjusted standardized morbidity ratio and 95% confidence intervals were attained by using the general population as the standard population group.Results: The age-adjusted standardized morbidity ratio of total injuries and poisonings was significantly high in the agriculture and fishery population. The standardized morbidity ratio was 137.6 in the male agriculture and fishery population and 123.3 in the female agriculture and fishery population. In terms of injuries and poisonings common to the agriculture and fishery population, the age-adjusted standardized morbidity ratio was significantly high regarding the dislocations and strains of lumbar spine/pelvis, shoulder and neck, the fracture of rib/thoracic spine/sternum and pesticide poisoning.Conclusions: The overall prevalence of injury/poisoning was significantly higher in the agriculture and fishery population than in the general population. Various forms of research should be conducted on the injuries of the agriculture and fishery population in the future. In order to compare the differences in the prevalence rates of injuries according to time and region, standard definitions of injuries and occupation related injuries are required.