• Title/Summary/Keyword: Self - sterile

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Transfer of Potato Virus Y (Necrotic strain) Resistance from Nicotiana africana to Nicotiana tabacum (Nicotiana Tabacum과 Nicotiana africana의 종간교배에 의한 감자바이러스 Y 저항성 유전자원 개발)

  • 금완수;정윤화;최상주;조명조;이승철
    • Journal of the Korean Society of Tobacco Science
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    • v.16 no.2
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    • pp.102-107
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    • 1994
  • This study was conducted to transfer the potato virus Y-necrosis strain resistance from Nicotiana africana to Nicotiana tabacum (cv. NC82) N. africana was crossed with NC82, GErmination of the cotyledon stage, at which time most of the seedling died. However, surviving seedlings continued to grow normally. Chromosomes of the these interspecific self-sterile F1 hybrids were doubled by tissue culture. Amphidiploid of F1 hybrid was self-fertile. Starting with amphidipliod, a wystematic backcross (BC) program was set up with NC82 as recurrent parent. In the BC5C2 generation, the resistant plant was selected. This resistant line, KF8833-1, had 48 chromosome and secreting glandular trichomes. It flowered 2days later than NC82, and stalk height, leaves per plant, leaf length and leaf width were similar to those of NC82.

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Molecular Comparison of Mating Type Loci and Adjacent Chromosomal Regions from Self-fertile and Self-sterile Cochliobolus Species

  • Yun, Sung-Hwan;B. Gillian Turgeon;Turgeon
    • The Plant Pathology Journal
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    • v.15 no.3
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    • pp.131-136
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    • 1999
  • In fungi known as ascomycetes, ability to mate is controlled by a single mating type (MAT) locus with two dissimilar sequences called idiomorphs carrying genes encoding transcription factors that are unrelated to each other. Fungi requiring strains with different MAT genes to complete the sexual process are heterothallic (self-sterile); species in which as single strain is able to undergo sexual reproduction are homothallic (self-fertile). Previous analysis of sequences from several heterothallic and homothallic species of the ascomycete genus Cochliobolus showed that homothallics evolve from heterothallics and that each known Cochliobolus homothallic species arose independently, from a different heterothallic ancestral species. Here we report detailed comparative analyses of MAT sequences ad their flanking regions, and show that: (1) The level of MAT gene similarity is not correlated with reproductive life style; (2) MAT proteins from all Cochliobolus species are conserved within the transcription factor signature sequences; they are not conserved in the carboxy terminal half of MAT-1, or third of MAT-2, except in those from very closely related species; (3) A gene (ORF1) of unknown function, consistently found on the MAT flank, is more conserved than are the MAT genes themselves; (4) The intergenic sequences diverge sharply among species.

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Interspecific Hybrid of Nicotiana trigonophyllo X N. tabacum through in vitro Culture of Fertilized Ovules (배주배양에 의한 Nicotiana trigonophylla와 N. tabacum의 종간잡종 육성)

  • 최상주;이승철
    • Journal of the Korean Society of Tobacco Science
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    • v.13 no.2
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    • pp.52-58
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    • 1991
  • Interspecific cross between Nicotiana trigonophylla and N. tabacum cv. BY4 is highly sterile because of abnormal ovule and embryo development. In vitro culture of excised N. trigonophylla ovules after polination by N. tabacum allows significant numbers of hybrid embryos to develop into mature plants. Total yield of seedlings and number of normal seedlings were produced following in vitro culture of individual fertilized ovules of N. trigonophylla X N. tabacum at four days post-pollination on B5 medium containing 6% sucrose. Hybrids were uniform in morphology and peroxidase isozyme composition and the majority were cytologically stable: flower characteristics were generally intermediate between those of the parents. All hybrids evaluated were self-sterile.

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Genetics of Self-fertility and Selection of Self-Fertile Lines in Rye (Secale cereale L.)

  • Heo, Hwa-Young;Hong, Byung-Hee;Seong, Rak-Chun;Ha, Yong-Woong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.45 no.5
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    • pp.343-346
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    • 2000
  • Rye breeding using F$_1$ hybrid began about 30 years ago, when cytoplasmically inherited forms of male sterility (CMS) and corresponding nuclear restorers were detected. It is very important to produce inbred lines for making hybrid lines because of strong self-incompatibility in rye. Among the 456 rye germplasms used in hybrid breeding scheme, 24 lines (5.3%) had the above 60% of self-fertility, and six lines of them were selected for their good agronomic characteristics and were used for subsequent inbreeding program. The average self-fertility of selected six lines was 78.4%, ranging from 72.2 to 99.5%. Genetic analysis for the self-fertility using $F_2$ populations showed that the segregation of self-fertile and sterile plants in F$_2$populations could be fit into 3 to 1 ratio suggesting self-fertility in rye be controlled by one major gene. The four different self-fertile lines, PI237923, 5C11, 5G5 and Florida black, had the same self-fertility gene because their F$_2$ plants showed almost the same self-fertility as their parents and showed no genetic segregation.

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Production of Sexual Hybrids Nicotiana rustica X N. tobacum via in vitro Culture .of Fertilized ovules. (배주배양에 의한 Nicotiana rustica와 N. tabacum의 잡종식물 육성)

  • 최상주;홍병희
    • Journal of the Korean Society of Tobacco Science
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    • v.14 no.1
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    • pp.3-11
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    • 1992
  • The present study examined various environmental and cultural media conditions for in vitro "rescue" of cross-fertilized ovules formed through sexual crosses between Nicotiana rustica and N. tabacum cv. BY4. The response ovules to two cultural procedures was compared; ovules were cultured either separately or left attached to the placenta. Total yield of seedlings and percent of normal seedlings were increased by culturing individual ovules separately, rather than on excised placenta. Total yield of seedlings and number of normal seedlings were produced following in vitro culture of individual fertilized ovules of N. rustica X M tabacum cv. BY4 at four days post-pollination on NN medium containing 2% sucrose. In the in vitro culture of fertilized ovules, high sucrose concentration increased the frequency of seedlings of abnormal appearance. Therefore, sucrose should be supplied to developing ovules at gradually decreased concentrations. Culture of fertilized ovules from three to eight days after pollination gave increased number of seedlings, but with delayed cultral time the number of morphologically normal seedling were decreased. Hybrids were uniform in appearance and showed vegetative heterosis but flower characteristics were generally intermediate between those of the parents. All hvbrids evaluated were self-sterile.f-sterile.

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Inheritance of Resistance to Potato Virus Y Vein- necrosis Strain of N. africana (N. africana의 감자바이러스Y 엽맥괴저 계통에 대한 저항성의 유전)

  • 금완수;정윤화;정석훈;최상주;이승철
    • Journal of the Korean Society of Tobacco Science
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    • v.13 no.2
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    • pp.48-51
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    • 1991
  • A program was initiated to transfer potato virus Y vein-necrosis strain resistance from N. africana to N. tabacum The Fl plants between the above species were self-sterile, but all amphidiploid plants from the Fl plants and backcrossed flowers, that is, the N. tabacum flowers crossed with amphidiploid were self-fertile. The parent, amphidiploid plants of Fl, F2 population of the amphidiploid and the backcrossed generation were screened for a resistance of potato virus Y vein-necrosis strain isolated in Korea. The Chi-square values for the F2 population of the amphidiploid and the backcrossed generation fitted 35: 1 and 5 : 1 ratios of resistant to susceptible for the potato virus Y vein-necrosis strain, respectively. Therefore, it was found that the resistance of N. tabacum for the potato virus Y vein-necrosis strain was controlled by a single dominant gene.

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Do Low Self-Esteem and High Stress Lead to Burnout Among Health-Care Workers? Evidence From a Tertiary Hospital in Bangalore, India

  • Johnson, Avita R.;Jayappa, Rakesh;James, Manisha;Kulnu, Avono;Kovayil, Rajitha;Joseph, Bobby
    • Safety and Health at Work
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    • v.11 no.3
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    • pp.347-352
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    • 2020
  • Background: Low self-esteem can be an issue among health-care workers due to the hierarchical medical system. Health-care workers are also in a high pressure environment that can lead to stress and burnout. This study was conducted to estimate the proportion of health-care workers with low self-esteem, high stress, and burnout and the factors associated with these in a private hospital in Bangalore city. Methods: This cross-sectional study included a random sample of health-care workers of various cadres - doctors, nurses, nursing aides, technicians, and workers in ancillary departments such as laundry, dietary, central sterile supply department, and pharmacy, with probability proportional to size. Rosenberg Scale for Self-esteem, Cohen's Perceived Stress Scale, and Shirom-Melamed Burnout Measure were used as study tools. Results: Among the 306 health-care workers, there were high levels of low self-esteem (48.4%), stress (38.6%), and burnout (48.7%), with the lowest levels being among doctors. Those aged younger than 30 years had significantly lower self-esteem and greater stress. Conclusions: Health-care workers with low self-esteem were nearly thrice more likely to suffer high stress, Odds Ratio (OR) = 2.84 (1.36-5.92), and those who were stressed had more than three times higher chance of experiencing burnout, OR = 3.6 (2.02-6.55). Path analysis showed that low self-esteem among health-care workers had a direct effect on burnout, as well as an indirect effect through stress (mediator variable). This study indicates the need for screening and counseling for low self-esteem, stress, and burnout as part of a periodic medical examination of all cadres of health workers.

Effect of Conidial Number and Nutrition on the Germination of Conidia in Septoria glycines (분생포자수 및 영양상태가 대두갈색무늬병균의 분생포자 발아에 미치는 영향)

  • Oh Jeung Haing;Chung Hoo Sup
    • Korean journal of applied entomology
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    • v.23 no.1 s.58
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    • pp.61-67
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    • 1984
  • Conidial germination of Septoria glycines Hemmi, brown spot fungus of soybean, was studied by slide germination test. Poor conidial germination of S. glycines was observed on sterile distilled water, but potato dextrose agar(PDA) and distilled water floated with soybean leaf disc furnished a satisfactory medium for conidial germination. Exogenous supply of carbon source was essential for conidial germination, while phosphorous and potassium were not evident as that for carbon. Soluble starch was the most suitable as a carbon source for conidial germination and followed by D-glucose, D-galactose and lactose in that order. Maximum germination was attained in the $5\times10^{-2}mol$. concentration of glucose. Germination was decreased with increment of conidial concentration and was almost completely suppressed in the density of 10,000 conidia per $mm^2$. It suggested existing a self-inhibitor(s). Non-washed conidia germinated more than washed conidia and this was obvious when the conidia density was over $2\times10^3$ conidia per $mm^2$ on the dry agar block.

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A Study of the Junior Nursing College Students실 Role during Clinical Practice (간호전문대학생들의 임상실습현장에서의 수행에 관한 연구 -실습의 내용 빈도를 중심으로-)

  • 권경남
    • Journal of Korean Academy of Nursing
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    • v.13 no.3
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    • pp.1-33
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    • 1983
  • The role and function of nursing care nowadays, tend to acquire sophisicated technology because specialization has expended due to increase of the medical population and the improvement of national health standards. To implement nursing care independently as a professional nurse, the apprehension of specific knowledge and skill should be acquired during basic nursing education. So it is important for nursing education not only to include theory and actual techniques, but also to strengthen the practical training in the actual clinical setting. This study was carried out with the following objectives; 1. To survey the detailed content and frequency of actual nursing students display during their clinical training. 2. To investigate the detailed content and frequency of actual nursing behavior which students display in each clinical a area. 3. To identify the motive for selection of nursing as their major and to determine the degree of self confidence, extent of knowledge and recognition of nursing responsibility. 4. To observe the relationship between actual nursing behavior and each of the following; 1) Motive for selecting nursing as a major 2) Self confidence 3) Knowledge of nursing care 4) Recognition of nursing responsibility The conclusions of this study were as follows; 1. Among the detailed nursing behavior which junior nursing college students carry out in clinical training; taking respiration's showed the highest frequency, and taking body temperatures, blood pressures, and pulses and making beds were next in frequency in this order. 2. In detailed nursing behaviors according to clinical area; taking vital signs showed the highest frequency in the emergency room, pediatric ward, orthopedic ward, general surgical ward and internal medicine ward. However, in the operating room, assisting with endotracheal tube insertion and sterile techniques were showen to have the highest frequencies. In nursery, umbilical cord care and the measurement of body weight were the highest in frequency In neurosurgical ward, the measurement of vital signs, changing position and tracheostomy care were the highest in frequency. In obstetric and gynecological ward and in the delivery room, checking duration, intensity and frequency of contractions was the highest in frequency. 3. In regard to the motive for majoring in nursing, the aptitude and interest of the student had the highest percentage(32.86%), and self-confidence in nursing activities (M=3.36), knowledge in nursing activities.(M=3. 09), and the recognition of the nursing activity (M= 3.76) wire in the middle range. 4. When the detailed nursing behaviors were compared with motive, self confidence, knowledge and recognition, it was found that when the nursing behavior was difficult and regarding much endeavor although the motive was high, the frequency of the nursing behavior was rather low. But in the cases in which there was much self confidence and a high level of skill was required, nursing behavior was carried more frequently. When there was muck self confidence and skill was not required, the frequency of nursing behavior was rather low. In the cases of a high level of knowledge, the frequency of nursing behavior was low and when recognition for nursing behavior was given the frequency of nursing behavior was low.

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Breeding of F1 Hybrid for Oriental Mustard(Brassica juncea L. Czern) Using the Cytoplasmic Male Sterile Line (웅성불임 인자를 이용한 갓(Brassica juncea L. Czern)의 F1 육종)

  • Park, Yong Ju;Min, Byung Whan
    • Journal of agriculture & life science
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    • v.52 no.6
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    • pp.27-36
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    • 2018
  • Recently, the demand for new cultivar of oriental mustard(Brassica juncea) is increased as the consumption of oriental mustard has increased dramatically in the market due to Kimchi is attracting the world's attention. However, absence of seed supply system can cause many problems including inbreeding depression due to self seed production, deterioration of the seed purity and heterogeneity of commercial seed. To establish the $F_1$ variety breeding system of oriental mustard, pure line and inbred lines were screened from inbreeding genetic resources. Male-sterile line was also selected from breeding combinations for the quality improvement of mustard. The combining ability from(Indojasai ${\times}$ Goheungdamyang) combinations and isolation line of(MS910 ${\times}$ Japan red mustard 8 ${\times}$ Ganghwa mustard 9) was highest, thus these lines were selected as parental lines. PCR(Polymerase Chain Reaction) and gene sequence analysis revealed that the genes related to CMS(orf263, orf220, and orf288) were distributed in mitochondria. The isolated lines from this study also showed good performance in yield test and farmhouse prove test.