• Current Research on Agriculture and Life Sciences
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• v.32 no.4
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• pp.185-188
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• 2014

The movement, survival, and weight gain of Helicoverpa armigera $H{\ddot{u}}bner$ (Lepidoptera: Noctuidae) first instar larvae were studied on CB9, CB10 and SR05 cotton varieties under field conditions. The neonate H. armigera were released on the cotton varieties at the squaring stage of the plants and, after a period of 72 hours, the survival, weight gain, and final location of the larvae were observed. While the different cotton varieties had no effect on the survival and weight gain of the larvae, the release locations on the cotton varieties had a significant influence on the larval survival and weight gain. The larvae fed small squares of the cotton varieties were significantly heavier and showed a higher mortality than the larvae fed leaflets and mature leaves. For the cotton varieties in this study, the larvae released on leaflets showed a significantly higher rate of recovery compared to the larvae released on mature leaves and squares. This study also found that that the larvae on leaflets did not move up or downward unlike the larvae on mature leaves and squares. This information on the foraging behavior of larvae on cotton varieties will assist researchers to interpret field data and thereby help with the development of pest management decisions.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.230-230
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• 2017

About 200 rice varieties for irrigated and rainfed lowland ecosystems were released in the Philippines, which were bred for improving yield under favorable conditions. Root plasticity plays key roles in maintaining crop productivity under abiotic stressed conditions. We hypothesized that some of these varieties possess root plasticity traits in response to water stressed conditions. This study aimed to evaluate the root system development and dry matter production of 14 randomly selected rice varieties (6 irrigated lowland and 9 rainfed varieties) under progressive drought (PDR) and soil moisture fluctuations (SMF) stress conditions. Two experiments were done in rootbox and line source sprinkler systems (LSS). Each of the varieties was subjected to well-watered (WW), PDR and SMF conditions during vegetative stage in rootbox system while the same genotypes were subjected to different intensities of drought stress under LSS. Under rootbox system, PDR and SMF significantly reduced shoot dry matter production in all varieties relative to their WW controls. Among varieties, NSIC Rc238 (irrigated lowland) showed the least reduction in shoot dry weight (SDW) in both PDR (by 11.8%) and SMF (by 26.9%) conditions. Less reductions in SDW of NSICRc238 were partially attributed to the promotion of L-type lateral roots, thus increasing total lateral root length by 24.2% and 30.7% under PDR and SMF, respectively. In LSS, SDW of NSIC Rc238 under mild drought stress (16-21% soil moisture content (SMC) had 31.8% reduction relative to its WW control (${\geq}22%SMC$) and had lower sensitivity drought index. Compared with the IR64 susceptible check and NSIC Rc9 tolerant check, NSIC Rc238 had higher SDW by 90.8% and 38.6%, respectively. Furthermore, no rainfed lowland varieties included in the experiment performed well under different water stress treatments. The results implied that some other irrigated lowland rice varieties may also possess drought dehydration avoidance root plasticity traits under water-stressed growing environments.

• Proceedings of the Korean Society of Crop Science Conference
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• 2000.04a
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• pp.262-263
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• 2000

• Journal of the East Asian Society of Dietary Life
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• v.11 no.1
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• pp.11-18
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• 2001

The saccharification and sensory characteristics of Sikhe, Korean traditional beverage of saccharified rice, made from thirteen glutinous rice varieties and one of non-glutinous rice named I1pum were examined. During saccharification, Shinsunchalbyeo, Whasunchalbyeo, Yukdononhrimna 1 and Hangangchalbyeo showed the highest sweetness determined by refractometer. Yukdononhrimna 1 was good for the morphology and texture of cooked rice kernel during saccharification. There was interrelationship between contents of released reducing sugar and sweetness determined by refractometer during preparation of Sikhe. The overall acceptability determined by sensory evaluation of Sikhe made from Yukdonongrimna 1, was slightly higher than that of Sikhe made from Ilpum, the non-glutionous rice variety. Yukdononhrimna 1 was considered to the most suitable varieties of Sikhe.

• Korean Journal of Plant Resources
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• v.2 no.1
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• pp.223-233
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• 1989

Recently, researches on oil crops Ln Korea were breeding on edible oil crops such as rapeseed sesame, peanut , periLla.Numerous varieties were released as a result of ective breedingworks on edible oil crops, that is 7 rape varieties including Yu-dal, Mokpo-11, Yongdang, Nozeogchae, Naehan, Yeongsanyuchae and Ch-eongpungyuchae (hybrid),5 varieties sesame including Suweon-5,9,21,Kwangsan99ae and Dabaekggae, 5 peanut varieties including Seodun-tangkonT,Yeonghotangkong, 01tankong , ShinpungtanTkong and SaedI-tanGkong, 3 periLLa varietLes including Daegu, Suweon8 and 10,res-pectively. This varietLes showed a good oil quality with high o-Leic and LinoLeic acids content, but periLLa oil seemed to be un-suitable for a edible use, since about 53 Percent of Its fatty a-cids was in the from of unsaturated LinoLenic acid.

• 한국균학회소식:학술대회논문집
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• 2014.10a
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• pp.41-41
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• 2014

Agaricus bisporus, commonly known as the button mushroom, is the most widely cultivated species of edible fungi. Low frequency of recombination ratio and homokaryotic or monokaryotic spore on meiotic basidia form obstacles for breeding programs. Since the first hybrid varieties for white button mushrooms were released in Europe, new varieties released afterwards were either identical of very similar to these first hybrids on morphologies. Therefore, different DNA markers have been used to define unique varieties of A. bisporus strains. Aim of this study is to assess the genetic diversity of different A. bisporus strains in Korea. Twelve UFP (Universal fungal primer, JK BioTech. Ltd), 12 simple sequence repeat (ISSR) and 30 SSR primers were used to assess genetic diversity of monokaryotic and dikaryotic Agaricus bisporus strains including other 19 Agaricus spp. Of them, four UFP, four SSR primers, $(GA)_8T$, $(AG)_8YC$, $(GA)_8C$ and $(CTC)_6$ and seven SSR markers produced PCR polymorphic bands between the Agaricus species or within A. bisporus strains. PCR polymorphic bands were inputted for UPGMA cluster analysis. Forty five strains of A. bisporus are genetically clustered into 6 groups, showing coefficient similarity from 0.75 to 0.9 among them. In addition, genetic variations of monokaryotic and dikaryotic Agaricus bisporus strains were partially detected by PCR technologies of this study. The varieties, Saea, saedo, Saejeong and Saeyeon that have recently been developed in Korea were involved in the same group with closely genetic relationship of coefficient similarity over 0.96, whereas, other strains were genetically related to A. bisporus strains that were introduced from USA, Eroupe and Chinese.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.470-479
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• 1982

Researches on industrial crops in Korea before 1962 were concentrated on fiber crops such as cotton, kenaf, hemp, ramie and flax. Then research works on oil crops, sugar crops and other high income crops were followed. However, no land is shared for the production of kenaf, flax, sugar beet, sweet sorghum and sunflower at present in Korea, while the cultivation of cotton, hemp, ramie and mat rush is decreasing continuously to the marginal point. At present researches are emphasized on oil crops such as seasame, peanut and perilla and high income medicinal herbs of which cultivating acreages are increasing. Numerous varieties were released as a result of active breeding works on industrial crops since 1962, i.e. 3 sesame varieties including "Suweon 21", 3 peanut varieties including "Seoduntangkong", and 6 rape varieties including "Yudal" in oil crops, one cotton variety "Mokpo 7", one hemp variety "MS4-1", and one kenaf variety "Suweon 2" in fiber crops, and two stevia varieties "Suweon 2" and "Suweon II" in sugar crops. Quality improvement of rape seeds and development of hybrid rapes utilizing male sterile lines are the most significant results of breeding works, while the establishment of vinyl mulching cultivation of sesame and peanut are the most successful results in agronomic researches during the last 20 years.re the most successful results in agronomic researches during the last 20 years.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.3
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• pp.241-248
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• 2009

Varietal differences on viviparous germination of newly released rice varieties were investigated to provide selection criteria for the high quality rice production. Laboratory and field tests were conducted on 20 different rice varieties in 2007. Varieties which showed below 10% of viviparous germination at the laboratory test were Odaebyo, Hitomebore, Koshihikari, Hwasungbyo, Hopyongbyo, Ilpumbyo, Chuchungbyo when they were treated 35 days after heading (DAH) at the temperature of 25/$15^{\circ}C$ (day/night) for 8 days, and were Hitomebore, Koshihikari, Hwasungbyo, Hopyongbyo under diurnal temperature of 30/$20^{\circ}C$ (day/night). At the field test with artificial lodging, there were 12 varieties including Hopyongbyo, Hitomebore that showed lower viviparous germination below 10% when they were treated at 35DAH and measured 8 days after lodging treatment but there was only four varieties (Ilpumbyo, Hwasungbyo, Chuchungbyo, Hopyongbyo) when lodging treatment was made at the 45DAH. Among newly released rice varieties, viviparous germination rate of Hopyongbyo was below 10% and was 11 to 20% at Hithomebore and Samgwangbyo, 21 to 40% at Koshihikari, Odae-No.1, Josaengheukchalbyo, Chonghobyo, 41 and 60% at Suean-No.1, Whongwangbyo, Bosukchalbyo, and 61 to 90% at Gopumbyo when it was examined 8 days after lodging treatment at 45DAH.

• Journal of the Korean Society of Tobacco Science
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• v.16 no.2
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• pp.122-127
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• 1994

Feeding preference of cigarette beetle, Lasioderma sewicorne F., on cured tobacco leaves was investigated to obtain basic information on ecological management of the insect pest in tobacco storage warehouses. About 3, 000-4, 000 adults of the insect were released in a warehouse in which groud tobacco leaves were placed on the bottom and at 3m above the floor level, and numbers of insects attracted were examined. There was no significant difference on feeding preference between the two tobacco varieties, flue-cured(NC82) and air-cured(Br3l) tobacco leaves. However, significant differences were noted in feeding preference between thick and thin leaves and among different quality grades within a tobacco variety. Feeding preferences of cigarette beetle between flue- and air- cured tobacco varieties showed significant differences on the lower position, though there were no differences on the 3m upper position. On the 3m upper position, feeding preferences were different between thick and thin leaves of tobacco varieties, and variety X thickness and variety X thickness equality grades showed statistically significant differences. Significantly higher feeding preference by cigarette beetle adults was observed for the food placed on the 3m upper than on the lower position. There were negative correlations between quality grades of cured tobacco leaves and feeding preference on the lower position, and the regression equation was Y(feeding preference)=4.050-0.683 X (degree).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.1
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• pp.1-21
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• 2020

Association mapping is widely used in rice and other crops to identify genes underlying important agronomic traits. Most association mapping studies use diversity panels comprising accessions with various geographical origins to exploit their wide genetic variation. While locally adapted breeding lines are rarely used in association mapping owing to limited genetic diversity, genes/alleles identified from elite germplasm are practically valuable as they can be directly utilized in breeding programs. In this study, we analyzed genetic diversity of 179 rice varieties (161 japonica and 18 Tongil-type) released in Korea from 1970 to 2006 using 192 microsatellite markers evenly distributed across the genome. The 161 japonica rice varieties were genetically very close to each other with limited diversity as they were developed mainly through elite-by-elite crosses to meet the specific local demands for high quality japonica rice in Korea. Despite the narrow genetic background, abundant phenotypic variation was observed in heading time, culm length, and amylose and protein content in the 161 japonica rice varieties. Using these varieties in association mapping, we identified six, seven, ten, and four loci significantly associated with heading time, culm length, and amylose and protein content, respectively. The sums of allelic effects of these loci showed highly significant positive correlation with the observed phenotypic values for each trait, indicating that the allelic variation at these loci can be useful when designing cross combinations and predicting progeny performance in local breeding programs.