• Journal of Plant Biotechnology
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• v.44 no.4
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• pp.438-447
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• 2017

Flowering is one of the most important development traits related to the production of Brassica rapa crops. After planting, a sudden low temperature triggers premature flowering, which leads to a reduction in the yield and quality of harvested production. Therefore, understanding the mechanism of flowering control is important in the agricultural productivity for preventing Brassica rapa crops. Vernalization is generally known as the main factor of flowering in the Brassica plant. However, in the subspecies of Brassica rapa, some accession such as Yellow sarson and Komatsuna display the flowering phenotype without vernalization. Circadian genes, which diurnally regulate plant physiology, have a role for photoperiodic flowering but are related to the regulation of the vernalizarion mechanism. In this report, the 22 B. rapa accession were divided into two groups, vernalization and non-vernalization, and the sequenced circadian gene, BrPRR1s. Among them, the BrPRR1b gene was found to have deletion regions, which could classify the two groups. The PCR primer was designed to amplify a short band of 422bp in the vernalization type and a long band of 451bp in the non-vernalization type. This primer set was applied to distinguish the flowering types in the 43 B. rapa accession and 4 Brassica genus crop, Broccoli, cabbage, mustard, and rape. The PCR analysis results and flowering time information of each crop demonstrated that the primer set can be used as marker to discern the flowering type in Brassica crops. This marker system can be applied to the B. rapa breeding when selecting the flowering character of new progenies or introducing varieties at an early stage. In addition, these results displayed that the circadian clock genes can be a good strategy for the flowering control of B. rapa crops.

• Korean Journal of Poultry Science
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• v.8 no.1
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• pp.1-5
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• 1981

In trying to predict the effect of genetics on the broiler in the year 2000, this is a relatively short period of time as far as broiler genetics in concerned. Modern broiler genetics started around 1945 and tremendous gains when made in past 35 years. Futher improvements on broiler will depend on the evolution and revolution: 1. Evolution: (1) Growth rate has been made 4-5% per year. (2) Feed conversion has improved approximately 1% per year. (3) Abdominal fat is becoming a major complaint in broiler. (4) Because of the changing life-style, broiler meat sales in the future will be more and more in cut-up form. (5) Breeding for stress resistance and selection for docile temperament can be important in order to funker improve fled efficiency. (6) In female parent stock, reproduction characteristics are in many can negatively correlated with the desired broiler traits. (7) Egg production and hatchability in moot commercial parent nod m at a fairly high level. (8) In male parent stock, the heavier and mon super-meat-type male lines are desired to Product better broilers. 2. Revolution: Trying to forecast revolutionary change in broiler genetics is highly speculative, as sudden change are aften unpredictable. (1) Species hybridization, such as a turkey-chicken cross (2) Biochemical tools, such as blood typing. (3) Mutation breeding by radiation or chemical mutagentia. (4) Broiler breeding would be to change the phenotypic appearance by single gene, such as naked, wingless. (5) Changes in production techniques. such as growing in cage or growing in filtered air positive pressure houses.

• Korean Journal of Poultry Science
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• v.15 no.3
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• pp.211-218
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• 1988

Data on egg number from time of first lay to 71 week of age were obtained from samples of single comb white leghorn breeder and brown layer breeder populations which were raised at manny breeding Co. These data were used to estimate the heritabilities of age at sexual maturity, early egg number, residual egg number and annual egg number. Also, the genetic correlation coefficients between these traits were estimated and selection efficiencies of each segment in early part record were estimated by use of the heritabilities and generic correlations. The estimated heritabilities and standard errors in two lines(W and B) were $0.30\pm0.07$ and $0.33\pm0.08$ at early records, $0.19\pm0.06$ and $0.18\pm$0.05 at residual records and $0.37\pm0.09$ and $0.49\pm0.10$ at time of first lay. Those at annual records were $0.24\pm0.06$ equally. The estimated correlation coefficients and standard errors between early record and annual record were $0.76\pm0.08$ and $0.77\pm0.07$. Those between early record and residual record were $0.46\pm0.15$ and $0.39\pm0.16$ respectively. At improving annual egg production per year, selection based on early part record(SM to 40 week of age) would be 69% more efficient than on annual record in line W and 80% more efficient than on annual record in line B. But, if it were considered that egg weight decreased due to sexual maturity and cost for data collection, use of selected segment from 35~40week of age in line W and from 31~40 week of age in line B would be desired in spite of a. small loss in relative selection efficiency. The generation interval would not be shortened.

• Journal of Plant Biotechnology
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• v.45 no.3
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• pp.171-182
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• 2018

Papaya (Carica papaya L.) is one of the crops widely planted in tropical and subtropical areas. The papaya fruit has low calories and are plentiful in vitamins A and C and in minerals. A major problem in papaya production is a plant disease caused by the papaya ringspot virus (PRSV). The first PRSV-resistant GM papaya expressing a PRSV coat protein gene was developed by USA scientists in 1992. The first commercial GM papaya cultivars derived from the event was approved by the US government in 1997. Development of transgenic papayas has been focused on vaccine production and limited agricultural traits, including insect and pathogen resistance, long shelf life, and aluminum and herbicide tolerance. Approximately 17 countries, including the USA and China, produced transgenic papayas and/or commercialized them, which provoked studies on biosafety assessment and development of GM-detection technologies. For the biosafety assessment of potential effects on human health, effects of long-term feeding to model animals have been studied in terms of toxicity and allergenicity. Studies on environmental safety assessment include influence on soil-microbial biodiversity and transfer to soil bacteria of GM selection markers. Many countries, such as Korea, the European Union, and Japan, that have strict regulations for GM crops have serious concerns about unintended introduction of GM cultivars and food commodities using unauthorized GM crops. Transgene- and/or GM event-specific molecular markers and technologies for genomics-based detection of unauthorized GM papaya have been developed and have resulted in the robust detection of GM papayas.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.323-323
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• 2017

In many sub-Saharan African countries, boosting rice production is a pressing food security issue. To contribute to the increase in rice production, we have developed lines of NERICA 1 introgressed with the gene for spikelet number, Gn1a, and the gene for primary rachis-branch number, WFP by cross breeding. The performance of rice lines introgressed with the genes for yield related traits can be affected by cultivation environment and management. Thus, in this study, we aimed to evaluate the lines of NERICA 1 introgressed with Gn1a or/and WFP for yield and yield components under different nitrogen fertilization conditions in Kenya. A field trial was conducted at a paddy field in Kenya Agricultural and Livestock Research Organization-Mwea, Kirinyaga County ($0^{\circ}39^{\prime}S$, $0^{\circ}20^{\prime}E$) from August 2016 to January 2017. Eight lines of NERICA 1 introgressed with Gn1a and/or WFP, and their parents, NERICA 1 and ST12, were grown under 0 (NF) and $75(SF)kg\;N\;ha^{-1}$. At maturity, five hills per plot were harvested to determine the yield and yield components. The number of primary and secondary rachis-branches per panicle was measured on the longest panicle in each hill. Under SF, the introgression of WFP to NERICA 1 increased the number of primary and secondary rachis-branches by 27 and 25%, respectively. On the other hand, Gn1a did not increase the number of primary rachis-branches, whereas the number of secondary rachis-branches was increased by 38% on average. The number of primary and secondary rachis-branches of the lines introgressed with both genes increased by 25 and 56%, respectively. Although grain number per panicle increased 33% by Gn1a, 34% by WFP, and 43% by Gn1a+WFP, the yield increase by Gn1a, WFP, and Gn1a+WFP was only 14, 7, and 14%, respectively. The suppression of the yield increase was mainly attributed to the decline in the filled grain ratio. Under NF, WFP increased the number of primary and secondary rachis-branches by 20 and 19%, respectively. The introgression of both genes increased the former and the later by 19 and 35%, respectively. However, Gn1a did not change them under NF. Thus, even under NF, grain yield increased 11% by WFP and 24% by Gn1a+WFP due to the increased grain number although filled grain ratio declined. Our findings suggest that the introgression of Gn1a and WFP could contribute to the rice productivity improvement in sub-Saharan Africa even under low fertility conditions. Improving filled grain ratio of the lines introgressed with these genes by further breeding and fertilization management will be the focus of subsequent work.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.6
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• pp.845-855
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• 2013

Requirements of dietary chloride (dCl) and chloride salts were determined by using $4{\times}2$ factorial arrangement under four phase feeding program. Four levels (0.31, 0.45, 0.59 and 0.73%) and two sources ($NH_4Cl$ and $CaCl_2$) of the dCl were allocated to 1,472 chicks in eight dietary treatments in which each treatment was replicated four times with 46 birds per replicate. The four phase feeding program was comprised of four dietary phases: Prestarter (d 1 to 10), Starter (d 11 to 20), Grower (d 21 to 33) and Finisher (d 34 to 42); and diets were separately prepared for each phase. The cations, anions, pH, dissolved oxygen (DO), temperature, electrical conductivity (EC), total dissolved solids (TDS) and salinity were analyzed in drinking water and were not affected by dietary treatments. BW gain (BWG; $p{\leq}0.009$) and feed:gain (FG; $p{\leq}0.03$) were improved in $CaCl_2$ supplemented diets during d 1 to 10. The maximum response of BWG and FG was observed at 0.38% and 0.42% dCl, respectively, for d 34 to 42. However, the level of dCl for BWG during d 21 to 33 ($p{\leq}0.04$) and d 34 to 42 ($p{\leq}0.009$) was optimized at 0.60% and 0.42%, respectively. The level of dCl for optimized feed intake (FI; $p{\leq}0.006$), FG ($p{\leq}0.007$) and litter moisture (LM; $p{\leq}0.001$) was observed at 0.60%, 0.38% and 0.73%, respectively, for d 1 to 42. Water intake (DWI) was not affected by increasing dCl supplementation (p>0.05); however, the ratio between DWI and FI (DWI:FI) was found highest at 0.73% dCl during d 1 to 10 ($p{\leq}0.05$) and d 21 to 33 ($p{\leq}0.009$). Except for d 34 to 42 ($p{\leq}0.006$), the increasing level of dCl did not result in a significant difference in mortality during any phase. Blood pH and glucose, and breast and thigh weights (percentage of dressed weight) were improved while dressing percentage (DP) and gastrointestinal health were exacerbated with $NH_4Cl$ as compared to $CaCl_2$ supplemented diets ($p{\leq}0.001$). Higher plasma $Na^+$ and $HCO_3{^-}$ and lower $Cl^-$ and $Ca^{{+}{+}}$ were observed in $NH_4Cl$ supplemented diets ($p{\leq}0.001$). Increasing supplementation of dCl increased plasma $Cl^-$ ($p{\leq}0.04$; quadratically) and linearly reduced plasma $K^+$ ($p{\leq}0.001$), $Ca^{{+}{+}}$ ($p{\leq}0.003$), $HCO_3{^-}$ ($p{\leq}0.001$), and $Na^+$ ($p{\leq}0.001$; quadratically). Consequently, higher requirements of dietary chloride are suggested for feed intake; nevertheless, lower levels of dietary chloride are sufficient to support optimal BWG and FG with increasing age. The $NH_4Cl$ supplemented diets ameliorate breast and thigh meat yield along with overall energy balance (glucose).

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.6
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• pp.812-820
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• 2002

An experiment was conducted on 190 progeny (winter -74; summer -59; rainy -57) of 12 Grey Giant rabbits (10 female +2 males), to assess the effect of different seasons in a year, on their reproductive, growth and productive performances along with feed efficiency, under sub-temperate Himalayan conditions. The daily meteorological attributes recorded during winter (October to March), summer (April to June) and rainy (July to September) seasons, and analysed were minimum and maximum temperature, relative humidity and rainfall. Various biological parameters recorded were doe weights at mating and kindling, litter size at birth, litter weight at birth, kit mortality, litter size at weaning, litter weight at weaning, weekly body weight up to 98 d and weaner mortality. Individual weight gains, dressing percentages, meat weights, liver weights, raw-pelt weights, processed pelt weights and processed pelt areas at slaughter on d 84 and 98, respectively were also recorded. The feed and fodder compositions and their nutritive values during different seasons were also analysed. Average ambient temperature during winter, summer and rainy seasons were $13.2{\pm}2.8$, $22.4{\pm}3.7$ and $24.8{\pm}2.3^{\circ}C$, respectively. The average relative humidity and total rainfall for winter, summer and rainy seasons were $68.9{\pm}1.5$% and $48{\pm}26.6$mm, $66.3{\pm}4.8$% and $125.6{\pm}56.8$ mm, and $77.3{\pm}1.3$% and $116.3{\pm}90.4$ mm, respectively. The weight of doe at mating and kindling, litter size at birth, litter weight at birth and litter size at weaning were comparatively higher whereas litter weight at weaning was significantly (p<0.05) higher during winter as compared to summer and rainy seasons. The kit mortality was significantly (p<0.05) higher during winter while the weaner mortality was significantly (p<0.05) higher during rainy season. At 84 d, the live weight per doe, slaughter weight, dressing percentage and liver weight were significantly (p<0.05) higher during winter than summer and rainy. Similarly, the gain in weight and meat weight at 84 and 98 d were significantly (p<0.05) higher during winter. The weight of raw pelt and processed pelt were recorded significantly (p<0.05) higher during winter while no difference in the area of processed pelts during different seasons could be observed. No difference in the biological performance could be observed between sexes in any of the seasons. Roughage analysis revealed comparatively higher crude protein percent and lower crude fibre percent during summer and rainy seasons than in winter. The roughage dry matter intake was comparatively higher during summer and rainy seasons vis-a-vis constant amount of concentrate supplied during all the three seasons. The digestibilities of dry matter was significantly (p<0.05) lower, whereas that of crude fiber, acid detergent fibre and cellulose were negative during winter. Interestingly, the feed:gain was exceedingly well during winter than in other seasons and it is concluded that it was the best season for production of rabbits under sub-temperate Himalayan conditions.

• Korean Journal of Heritage: History & Science
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• v.52 no.3
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• pp.56-73
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• 2019

This paper aims to establish the technical style of roof tiles by analyzing East Asian roof tile making techniques. It will examine the existing main research data, such as excavation results and the subsequent analysis of the roof tiles' production traces, as well as references and transmitted techniques. Regions are grouped according to technical similarity, then grouped again by artistic styles of pattern and shape and by the technical styles of tools, procedures, and manpower plans. Accordingly, intends to find out whether an understanding of technical style can facilitate an understanding of not only cultural aspects, but also the causality of techniques. Korean, Chinese and Japanese tools were examined, and procedures for making roof tiles were classified into 4 groups. In a superficial way, China, Okinawa, Korea, and Honshu share similar technical traits. Research of procedural details and manpower plans revealed characteristics of each region. As a result, comparisons were made between each region's technical characteristics attempting to investigate their causes. The groups were classified according to their possessing techniques, but it was revealed that East Asia's shared production techniques were based on architectural methodss. The skill of "Pyeon Jeol(Clay Cutting)" classified according to its possessing techniques, turned out to be one such technique. Also, the procedure of technical localization based on the skill of "Ta-nal(Tapping)" showed that the condition of this technique was the power to localize in response to a transfer of techniques. Previous comparison parameters of artifacts would have been a similarity of style originated from exchanges between regions and stylistic characteristics of regions decided by the demander's taste of beauty. This methodology enlarges cultural perception and affords a positive basis of historical facts. However, it suggests the possibility of finding cultural aspects' origins by understanding the technical style and seeing same result in view of "technology culture."

• Korean Journal of Breeding Science
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• v.51 no.3
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• pp.214-221
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• 2019

'Aram' is a soybean cultivar developed for soy-sprout. It was developed from the crossing of 'Bosug' (Glycine max IT213209) and 'Camp' (G. max IT267356) cultivars in 2007. F₁ plants and F₂ population were developed in 2009 and 2010. A promising line was selected in the F₅ generation in 2011 using the pedigree method and it was evaluated for agronomic traits, yield, and soy-sprouts characteristics in a preliminary yield trial (PYT) in 2012 and an advanced yield trial (AYT) in 2013. Agronomic traits and yield were stable between 2014 and 2016 in the regional yield trial (RYT) in four regions (Suwon, Naju, Dalseong, and Jeju). Morphological characteristics of 'Aram' are as follows: determinate plant type, purple flowers, grey pubescence, yellow pods, and small, yellow, and spherical seeds (9.9 g 100-seeds^-1) with a light brown hilum. The flowering date was the 5^th of August and the maturity date was the 15^th of October. Plant height, first pod height, number of nods, number of branches, and number of pods were 65 cm, 13 cm, 16, 4.5, and 99, respectively. In the sprout test, germination rate and sprout characteristics of 'Aram' were comparable to that of the 'Pungsannamulkong' cultivar. The yield of 'Aram' was 3.59 ton ha^-1 and it was 12% higher than that of 'Pungsannamulkong' in southern area of Korea. The yield of 'Aram' in the Jeju region, which is the main region for soybean sprout production, was 20% higher than that of 'Pungsannamulkong'. The height of the first pod and the tolerance to lodging and pod shattering, which are connected to the adaptation to mechanized harvesting, were higher in 'Aram' compared to those in 'Pungsannamulkong'. Therefore, the 'Aram' cultivar is expected to be broadly cultivated because of its higher soybean sprout quality, and seed yield and better adaptation to mechanized harvesting. (Registration number: 7718)

• Asia pacific journal of information systems
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• v.19 no.4
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• pp.125-148
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• 2009

UGC(User Generated Contents) is emerging as the center of e-business in the web 2.0 era. The trend reflects changing roles of users in production and consumption of contents on websites and helps us to understand new strategies of websites such as web portals and social network websites. Nowadays, we consume contents created by other non-professional users for both utilitarian (e.g., knowledge) and hedonic values (e.g., fun). Also, contents produced by ourselves (e.g., photo, video) are posted on websites so that our friends, family, and even the public can consume those contents. This means that non-professionals, who used to be passive audience in the past, are now creating contents and share their UGCs with others in the Web. Accessible media, tools, and applications have also reduced difficulty and complexity in the process of creating contents. Realizing that users create plenty of materials which are very interesting to other people, media companies (i.e., web portals and social networking websites) are adjusting their strategies and business models accordingly. Increased demand of UGC may lead to website visits which are the source of benefits from advertising. Therefore, they put more efforts into making their websites open platforms where UGCs can be created and shared among users without technical and methodological difficulties. Many websites have increasingly adopted new technologies such as RSS and openAPI. Some have even changed the structure of web pages so that UGC can be seen several times to more visitors. This mainstream of UGCs on websites indicates that acquiring more UGCs and supporting participating users have become important things to media companies. Although those companies need to understand why general users have shown increasing interest in creating and posting contents and what is important to them in the process of productions, few research results exist in this area to address these issues. Also, behavioral process in creating video UGCs has not been explored enough for the public to fully understand it. With a solid theoretical background (i.e., theory of implementation intentions), parts of our proposed research model mirror the process of user behaviors in creating video contents, which consist of intention to upload, intention to edit, edit, and upload. In addition, in order to explain how those behavioral intentions are developed, we investigated influences of antecedents from three motivational perspectives (i.e., intrinsic, editing software-oriented, and website's network effect-oriented). First, from the intrinsic motivation perspective, we studied the roles of self-expression, enjoyment, and social attention in forming intention to edit with preferred editing software or in forming intention to upload video contents to preferred websites. Second, we explored the roles of editing software for non-professionals to edit video contents, in terms of how it makes production process easier and how it is useful in the process. Finally, from the website characteristic-oriented perspective, we investigated the role of a website's network externality as an antecedent of users' intention to upload to preferred websites. The rationale is that posting UGCs on websites are basically social-oriented behaviors; thus, users prefer a website with the high level of network externality for contents uploading. This study adopted a longitudinal research design; we emailed recipients twice with different questionnaires. Guided by invitation email including a link to web survey page, respondents answered most of questions except edit and upload at the first survey. They were asked to provide information about UGC editing software they mainly used and preferred website to upload edited contents, and then asked to answer related questions. For example, before answering questions regarding network externality, they individually had to declare the name of the website to which they would be willing to upload. At the end of the first survey, we asked if they agreed to participate in the corresponding survey in a month. During twenty days, 333 complete responses were gathered in the first survey. One month later, we emailed those recipients to ask for participation in the second survey. 185 of the 333 recipients (about 56 percentages) answered in the second survey. Personalized questionnaires were provided for them to remind the names of editing software and website that they reported in the first survey. They answered the degree of editing with the software and the degree of uploading video contents to the website for the past one month. To all recipients of the two surveys, exchange tickets for books (about 5,000~10,000 Korean Won) were provided according to the frequency of participations. PLS analysis shows that user behaviors in creating video contents are well explained by the theory of implementation intentions. In fact, intention to upload significantly influences intention to edit in the process of accomplishing the goal behavior, upload. These relationships show the behavioral process that has been unclear in users' creating video contents for uploading and also highlight important roles of editing in the process. Regarding the intrinsic motivations, the results illustrated that users are likely to edit their own video contents in order to express their own intrinsic traits such as thoughts and feelings. Also, their intention to upload contents in preferred website is formed because they want to attract much attention from others through contents reflecting themselves. This result well corresponds to the roles of the website characteristic, namely, network externality. Based on the PLS results, the network effect of a website has significant influence on users' intention to upload to the preferred website. This indicates that users with social attention motivations are likely to upload their video UGCs to a website whose network size is big enough to realize their motivations easily. Finally, regarding editing software characteristic-oriented motivations, making exclusively-provided editing software more user-friendly (i.e., easy of use, usefulness) plays an important role in leading to users' intention to edit. Our research contributes to both academic scholars and professionals. For researchers, our results show that the theory of implementation intentions is well applied to the video UGC context and very useful to explain the relationship between implementation intentions and goal behaviors. With the theory, this study theoretically and empirically confirmed that editing is a different and important behavior from uploading behavior, and we tested the behavioral process of ordinary users in creating video UGCs, focusing on significant motivational factors in each step. In addition, parts of our research model are also rooted in the solid theoretical background such as the technology acceptance model and the theory of network externality to explain the effects of UGC-related motivations. For practitioners, our results suggest that media companies need to restructure their websites so that users' needs for social interaction through UGC (e.g., self-expression, social attention) are well met. Also, we emphasize strategic importance of the network size of websites in leading non-professionals to upload video contents to the websites. Those websites need to find a way to utilize the network effects for acquiring more UGCs. Finally, we suggest that some ways to improve editing software be considered as a way to increase edit behavior which is a very important process leading to UGC uploading.