• Title/Summary/Keyword: Seed collection

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Occurrence and Survival Rate of the Larvae of Ark Shell Anadara broughtonii in Chinhae Bay (진해만(鎭海灣)에서의 피조개 Anadara broughtonii 부유유생(浮游幼生)의 출현(出現)과 생존율(生存率))

  • Yoo, Sung Kyoo;Lim, Hyun Sig;Ryu, Ho Young
    • 한국해양학회지
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    • v.23 no.2
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    • pp.70-75
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    • 1988
  • In order to set up a predictive model for an effective spat collection of ark shells, Anadara broughtonii, the survival rate and the time required for each developmental stage of planktonic larvae were investigated during the period from July 1 to October 30 in 1974, in one of the main ark shell seed collection areas, Chinhae Bay, in the southern part of Korea. The advent of D-shaped larvae ca. $94.3{\times}72.7{\mu}m$ long had three peaks during the surveyed period: August 25, August 31 and September 9, umbo-shaped larvae ca. $141.6{\times}108.4{\mu}m$ and full grown larvae ca. $269.3{\times}221.7{\mu}m$ long also showed three peaks: September 6, September 12 and September 20 for the former, and September 20, September 25 and October 5 for the latter, respectively. About 11 to 12 days was required for D-shaped larvae to develop to umbo-shaped stage. At this intermorphological stage, the daily survival rate was 0.93 with a total survival rate of 45% for the stage. The time required for umbo-shaped larvae to develop to full grown larvae varied from 13 to 15 days with a daily survival rate of 0.93 and with a total survival rate of 36% in the period. Twenty-five to twenty-six days were required for each peak group of the D-shaped larvae to reach a full grown stage, and their total survival rate was 16% during this developmental stage.

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Plant Characters of Selfed MET Maize Line (자식(自殖)된 다수다얼성(多穗多蘖性) 옥수수(MET)의 특성(特性) 비교(比較) 시험(試驗))

  • Choe, Bong Ho;Lee, Hee Bong
    • Korean Journal of Agricultural Science
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    • v.12 no.2
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    • pp.166-173
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    • 1985
  • The multiple ear and tiller line (MET), which was selected from a local maize collection and has been selected for earliness by selfing for five generations, was compared its plant characteristics with four U.S. leading hybrids. 1. The general plant growth was a little retarded by poor soil fertility and structure. 2. The fresh weight of the MET line was about 97.8% of the U.S. check varieties. 3. The dry weight of the MET line was also about 94.5% of the check U.S. hybrids (1,695 kg / 10a.). 4. The tillering and eating habits of the MET line had contributed toward increasing fresh and dry weight of the MET line. 5. The average plant height of the MET line was much less than those of the check varieties, due to the selfing depression manifested by the MET line, (234.7cm. of the MET vs 250.7cm. of the check) 6. Apparent differences of disease resistance was observed among varieties studied. The degree of plants infected with the black stripe mosaic virus was over 20% for the check U.S. hybrids, while less than 5% of the MET line was infected with the disease. 7. The grain yield per 10 a of the MET line was far below the check hybrids due to the inbreeding depression of the MET line. However, the kernel number per unit area of the MET line with small size kernel was much greater than that of the check hybrids. The 100 kernel weight of the MET line was around 10 grams. 8. The average fresh and dry matter weight of the three ($sorghum{\times}sudan$ grass) varieties was very much alike with those of the MET line. 9. In conclusion, the use of the MET line for silage production may have dual adventages because of its low seed price and of its small size kernels, which may reduce the amount of seeds required for planting in an unit area.

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Changes of Mating Type Distribution and Fungicide-resistance of Phytophthora infestans Collected from Gangwon Province (강원지역 감자 역병균 Phytophthora infestans의 교배형 및 약제저항성 변화)

  • Park, Kyeong-Hun;Ryu, Kyoung-Yul;Yun, Jeong-Chul;Jeong, Kyu-Sik;Kim, Jeom-Soon;Kwon, Min;Kim, Byung-Sup;Cha, Byeong-Jin
    • Research in Plant Disease
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    • v.16 no.3
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    • pp.274-278
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    • 2010
  • Potato late blight caused by Phytophthora infestans was the most constrain disease at potato cultivation areas. The mating type distribution and fungicides response of P. infestans were investigated to elucidate the changes of pathogen from Gangwon province. On the fungal isolates in 2006, 58.7% were A1 mating type and 41.3% were A2 mating type. In 2007, A1 mating type isolates increased to 93.3% and A2 mating type isolates were collected from Jinbu areas as much as 6.7%. About 234 isolates analysed for metalaxyl response, the results was resistance 73.7%, intermediate 18.8% and sensitive 7.5% in 2006. And it was resistance 59.4%, intermediate 4.0% and sensitive 36.6% in 2007. It meant that mating type distribution and fungicide response were very different over the collection sites. Minimal inhibition concentration (MIC) of dimethomorph examined with 126 isolates in 2006 and 106 isolates in 2007. MIC over $1.0\;{\mu}g/ml$ was 56.3% in 2006 and it was 3.8% in 2007. The average $EC_{50}$ value of P. infestans was $0.37\;{\mu}g/ml$ in 2006, but it decreased to $0.12\;{\mu}g/ml$ in 2007. Fungicides response and pathogenesis of P. infestans should be monitored continuously to enhance the chemical efficacy at potato fields.

Current status and prospects of molecular marker development for systematic breeding program in citrus (감귤 분자육종을 위한 분자표지 개발 현황 및 전망)

  • Kim, Ho Bang;Kim, Jae Joon;Oh, Chang Jae;Yun, Su-Hyun;Song, Kwan Jeong
    • Journal of Plant Biotechnology
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    • v.43 no.3
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    • pp.261-271
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    • 2016
  • Citrus is an economically important fruit crop widely growing worldwide. However, citrus production largely depends on natural hybrid selection and bud sport mutation. Unique botanical features including long juvenility, polyembryony, and QTL that controls major agronomic traits can hinder the development of superior variety by conventional breeding. Diverse factors including drastic changes of citrus production environment due to global warming and changes in market trends require systematic molecular breeding program for early selection of elite candidates with target traits, sustainable production of high quality fruits, cultivar diversification, and cost-effective breeding. Since the construction of the first genetic linkage map using isozymes, citrus scientists have constructed linkage maps using various DNA-based markers and developed molecular markers related to biotic and abiotic stresses, polyembryony, fruit coloration, seedlessness, male sterility, acidless, morphology, fruit quality, seed number, yield, early fruit setting traits, and QTL mapping on genetic maps. Genes closely related to CTV resistance and flesh color have been cloned. SSR markers for identifying zygotic and nucellar individuals will contribute to cost-effective breeding. The two high quality citrus reference genomes recently released are being efficiently used for genomics-based molecular breeding such as construction of reference linkage/physical maps and comparative genome mapping. In the near future, the development of DNA molecular markers tightly linked to various agronomic traits and the cloning of useful and/or variant genes will be accelerated through comparative genome analysis using citrus core collection and genome-wide approaches such as genotyping-by-sequencing and genome wide association study.

Financial Fraud Detection using Text Mining Analysis against Municipal Cybercriminality (지자체 사이버 공간 안전을 위한 금융사기 탐지 텍스트 마이닝 방법)

  • Choi, Sukjae;Lee, Jungwon;Kwon, Ohbyung
    • Journal of Intelligence and Information Systems
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    • v.23 no.3
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    • pp.119-138
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    • 2017
  • Recently, SNS has become an important channel for marketing as well as personal communication. However, cybercrime has also evolved with the development of information and communication technology, and illegal advertising is distributed to SNS in large quantity. As a result, personal information is lost and even monetary damages occur more frequently. In this study, we propose a method to analyze which sentences and documents, which have been sent to the SNS, are related to financial fraud. First of all, as a conceptual framework, we developed a matrix of conceptual characteristics of cybercriminality on SNS and emergency management. We also suggested emergency management process which consists of Pre-Cybercriminality (e.g. risk identification) and Post-Cybercriminality steps. Among those we focused on risk identification in this paper. The main process consists of data collection, preprocessing and analysis. First, we selected two words 'daechul(loan)' and 'sachae(private loan)' as seed words and collected data with this word from SNS such as twitter. The collected data are given to the two researchers to decide whether they are related to the cybercriminality, particularly financial fraud, or not. Then we selected some of them as keywords if the vocabularies are related to the nominals and symbols. With the selected keywords, we searched and collected data from web materials such as twitter, news, blog, and more than 820,000 articles collected. The collected articles were refined through preprocessing and made into learning data. The preprocessing process is divided into performing morphological analysis step, removing stop words step, and selecting valid part-of-speech step. In the morphological analysis step, a complex sentence is transformed into some morpheme units to enable mechanical analysis. In the removing stop words step, non-lexical elements such as numbers, punctuation marks, and double spaces are removed from the text. In the step of selecting valid part-of-speech, only two kinds of nouns and symbols are considered. Since nouns could refer to things, the intent of message is expressed better than the other part-of-speech. Moreover, the more illegal the text is, the more frequently symbols are used. The selected data is given 'legal' or 'illegal'. To make the selected data as learning data through the preprocessing process, it is necessary to classify whether each data is legitimate or not. The processed data is then converted into Corpus type and Document-Term Matrix. Finally, the two types of 'legal' and 'illegal' files were mixed and randomly divided into learning data set and test data set. In this study, we set the learning data as 70% and the test data as 30%. SVM was used as the discrimination algorithm. Since SVM requires gamma and cost values as the main parameters, we set gamma as 0.5 and cost as 10, based on the optimal value function. The cost is set higher than general cases. To show the feasibility of the idea proposed in this paper, we compared the proposed method with MLE (Maximum Likelihood Estimation), Term Frequency, and Collective Intelligence method. Overall accuracy and was used as the metric. As a result, the overall accuracy of the proposed method was 92.41% of illegal loan advertisement and 77.75% of illegal visit sales, which is apparently superior to that of the Term Frequency, MLE, etc. Hence, the result suggests that the proposed method is valid and usable practically. In this paper, we propose a framework for crisis management caused by abnormalities of unstructured data sources such as SNS. We hope this study will contribute to the academia by identifying what to consider when applying the SVM-like discrimination algorithm to text analysis. Moreover, the study will also contribute to the practitioners in the field of brand management and opinion mining.