• Journal of Crop Science and Biotechnology
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• 제11권4호
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• pp.269-276
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• 2008

Field resistance is defined as the resistance that allows effective control of a parasite under natural field condition and is durable when exposed to new races of that parasite. To identify the genes for field resistance to rice blast, quantitative trait loci (QTLs) conferring the resistance for races and blast nursery screening in japonica rice cultivars were detected and mapped using SSR markers. QTL analysis was carried out in 190 RILs population from the cross between Suweon365 (moderately resistant) and Chucheong (highly susceptible). Twelve QTLs against nine blast races inoculated were detected on chromosomes 1, 2, 4, 6, 7, 11 and 12. They explained from 5.1% to 34.9% of total phenotypic variation. Eight QTLs against blast nursery screening in four regions for three years were detected on chromosomes 1, 2, 4, 11 and 12. The phenotypic variation explained by each QTL ranged from 4.3% to 37.7%. Three chromosome segment substitution lines (CSSLs) of $BC_2F_6$ by backcross method were developed to transfer the QTLs into the susceptible cultivar Chucheong as a recurrent parent. A CSSL4-1 containing two QTLs qLB6.2 and qLB7 against blast races showed to the reaction of 6 to 7 at blast nursery in two regions for two years. The CSSL4-2 and CSSL93 containing QTLs, qLB11.2 and qLB12.1 of the resistance against leaf blast in blast nursery screening, respectively, had enhanced the resistance for blast nursery screening across two regions and in two years.

• 한국식품영양학회지
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• 제31권1호
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• pp.149-159
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• 2018

The change of quality and physicochemical characteristics of mung-bean flours after germination and roasting treatment were evaluated. The moisture content of the roasted mung-bean flours decreased significantly according to the roasting temperatures and times, and the crude ash, protein and fat contents increased. The lightness of the roasted mung-bean flours significantly decreased, and the redness and yellowness increased. The water binding capacity of the roasted mung-bean flours without and with germination were 151.71 and 192.77% at $240^{\circ}C$ for 20 min, respectively. The water solubility index and swelling power decreased with an increase in roasting temperatures and times. The phenolic compounds and radical scavenging activity of the roasted mung-bean flours increased with an increase in the roasting temperatures and times. The total polyphenol contents of the roasted mung-bean flours without and with germination were 4.81~7.71 and 4.22~5.63 mg GAE/g, and the total flavonoid contents were 2.46~3.05 and 2.45~2.87 mg CE/g, respectively. The DPPH radical scavenging activity of the roasted mung-bean flours, without and with germination, were 106.83~376.08 and 174.41~346.70 mg TE/100 g, and the ABTS radical scavenging activity was 251.67~534.31 and 274.39~430.02 mg TE/100 g, respectively. As a result, it is necessary to set quality standards for each application considering the quality and antioxidant properties of the roasted mung-bean flours.

• 한국약용작물학회지
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• 제24권2호
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• pp.101-109
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• 2016

Background: The purpose of this study was to evaluate methods to reduce seeding expenses, thereby increasing farm income. This study investigated the effects of rain shelter controlled cultivation and adapted seeding times on the stable seed production of Scutellaria baicalensis Georgi. Methods and Results: Seed germination was conducted under 10 condition compose to control, water washing, cold storage at $4^{\circ}C$ for 15 days, seed sterilization with a benomyl pesticides, hormone treated seed by submerging in 100 ppm $GA_3$ with the cold storage at $20^{\circ}C$ and $25^{\circ}C$, darkness in a covered petridish and illuminated with a 1,500 Lux lamp. There were three cultivation type, open cultivation with non-woven fabric mulching, cultivation with a vinyl covering and rain sheltered in a plastic greenhouse. Sowing dates were April 27, May 18, June 7 and June 28, 2013. Plants were spaced 10 cm apart in rows 30 cm apart. Mixed oil cake fertilizer, $N-P_2O_5-K_2O$ (12-10-10) was applied at $600kg{\cdot}10a^{-1}$. Conclusions: Optimum germination occured in darkness at $25^{\circ}C$ and cold storage after submerging in $GA_3$. The highest seed yields ($4.5kg{\cdot}10a^{-1}$) occurred in the plastic greenhouse for the April 25 sowing. The highest root yield (17%) was found on April 1, under greenhouse conditions.

• 한국작물학회지
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• 제64권3호
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• pp.246-268
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• 2019

Soybean [Glycine max (L.) Merr.] is a species of legume native to East Asia. The interactions between climatic conditions and genetic characteristics are known to affect the agricultural performance of soybean. Therefore, the present investigation was conducted to identify the main elements affecting the agricultural performances of 11 soybean varieties/lines from China [Harbin ($45^{\circ}12^{\prime}N$), Yanji ($42^{\circ}53^{\prime}N$), Dalian ($39^{\circ}30^{\prime}N$), Qingdao ($36^{\circ}26^{\prime}N$)] and the Republic of Korea [Suwon ($37^{\circ}16^{\prime}N$), and Jeonju ($35^{\circ}49^{\prime}N$)]. The days to flowering (DTF) of soybeans with the e1-nf and e1-as alleles and the E1e2e3e4 genotype, except in 'Keumgangkong', 'Tawonkong', and 'Duyoukong', were relatively short compared to those of soybeans with other alleles. Although DTF of the soybeans was highly correlated with all climatic conditions [negative: precipitation, average temperature (AVT), accumulated temperature; positive: day-length (DL)], days to maturity and 100-seed weight of the soybeans showed no significant correlation with any climatic conditions. The soybeans with a dominant Dt1 allele, except 'Tawonkong', had the longest stem length (STL). Moreover, STL of the soybeans grown in the test fields showed a positive correlation with only DL; however, the results of our chamber test that was conducted to complement the field tests showed that STL of soybean was positively affected by AVT and DL. Although soybean yield (YLD) showed positive correlations with latitude and DL (except L62-667, OT89-5, and OT89-6), the response of YLD to the climatic conditions was cultivar-specific. Our results show that DTF and STL of soybeans grown in six different latitudes are highly affected by DL, and AVT and genetic characteristic also affect DTF and STL.

• 환경생물
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• 제40권4호
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• pp.423-432
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• 2022

미국선녀벌레 생물적 방제를 위한 기생성 천적인 선녀벌레집게벌 대량사육 체계를 구축하였다. 선녀벌레집게벌 고치 생산은 기주인 미국선녀벌레 약충밀도와 기주식물의 재식밀도에 따른 차이를 보였지만, 뽕나무 기주식물 잎당 평균 5~8개, 주당 평균 70~150개가 생산되었다. 선녀벌레집게벌 암컷 평균 고치 길이는 6.01~6.46 mm, 수컷은 4.20~4.62 mm로 암수 간 통계적으로 유의미한 차이를 보였으며, 우화 전 고치상태에서의 암수 구분으로 선녀벌레집게벌을 효과적으로 방사할 수 있을 것으로 보인다. 반야외조건에서 선녀벌레집게벌 기생률은 평균 13~17%로, 방사 마리수에 따른 기생률 차이는 확인되지 않았으나 방사 마리수가 많을수록 미국선녀벌레 개체군밀도증가율이 낮아지는 경향을 보였다. 선녀벌레집게벌의 성비나 이화성은 기주의 영기에 따라 달라졌다. 기주의 영기가 낮을수록 이화성 비율이 증가했고, 4~5령 약충에 기생시 암컷의 비율이 높게 나타나 대량사육 시 개체조절이 가능할 것으로 판단된다.

• 한국작물학회지
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• 제36권2호
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• pp.112-126
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• 1991

The atmospheric carbon dioxide concentration is ever-increasing and expected to reach about 600 ppmv some time during next century. Such an increase of $CO_2$ may cause a warming of the earth's surface of 1.5 to 4.5$^{\circ}C$, resulting in great changes in natural and agricultural ecosystems. The climatic scenario under doubled $CO_2$ projected by general circulation model of Goddard Institute for Space Studies(GISS) was adopted to evaluate the potential impact of climate change on agroclimatic resources, net primary productivity and rice productivity in Korea. The annual mean temperature was expected to rise by 3.5 to 4.$0^{\circ}C$ and the annual precipitation to vary by -5 to 20% as compared to current normal climate (1951 to 1980), resulting in the increase of possible duration of crop growth(days above 15$^{\circ}C$ in daily mean temperature) by 30 to 50 days and of effective accumulated temperature(EAT=∑Ti, Ti$\geq$1$0^{\circ}C$) by 1200 to 150$0^{\circ}C$. day which roughly corresponds to the shift of its isopleth northward by 300 to 400 km and by 600 to 700 m in altitude. The hydrological condition evaluated by radiative dryness index (RDI =Rn/ $\ell$P) is presumed to change slightly. The net primary productivity under the 2$\times$$CO_2$ climate was estimated to decrease by 3 to 4% when calculated without considering the photosynthesis stimulation due to $CO_2$ enrichment. Empirical crop-weather model was constructed for national rice yield prediction. The rice yields predicted by this model under 2 $\times$ $CO_2$ climatic scenario at the technological level of 1987 were lower by 34-43% than those under current normal climate. The parameters of MACROS, a dynamic simulation model from IRRI, were modified to simulate the growth and development of Korean rice cultivars under current and doubled $CO_2$ climatic condition. When simulated starting seedling emergence of May 10, the rice yield of Hwaseongbyeo(medium maturity) under 2 $\times$ $CO_2$ climate in Suwon showed 37% reduction compared to that under current normal climate. The yield reduction was ascribable mainly to the shortening of vegetative and ripening period due to accelerated development by higher temperature. Any simulated yields when shifted emergence date from April 10 to July 10 with Hwaseongbyeo (medium maturity) and Palgeum (late maturity) under 2 $\times$ $CO_2$ climate did not exceed the yield of Hwaseongbyeo simulated at seedling emergence on May 10 under current climate. The imaginary variety, having the same characteristics as those of Hwaseongbyeo except growth duration of 100 days from seedling emergence to heading, showed 4% increase in yield when simulated at seedling emergence on May 25 producing the highest yield. The simulation revealed that grain yields of rice increase to a greater extent under 2$\times$ $CO_2$-doubled condition than under current atmospheric $CO_2$ concentration as the plant type becomes more erect.

• 한국잡초학회지
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• 제13권2호
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• pp.159-163
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• 1993

건답직파(乾畓直播)를 연속(繼續)함에 따라서 야기되는 잡초군락(雜草群落)의 변이양상(變異樣相)을 밝혀 효과적(效果的)인 제초체계(除草體系)를 확립(確立)하고자 수행(遂行)한 결과(結果)는 다음과 같다. 1. 벼 건답직파재배(乾畓直播栽培)를 4년간(年間) 연속재배(連續栽培)한 경우 화본과잡초(禾本科雜草)는 감소(減少)한 반면 광엽잡초(廣葉雜草)는 증가(增加)하였으며 생활형(生活型)으로 보면 1년생잡초(年生雜章)는 증가(增加)하였으나 다년생잡조(多年生雜草)는 감소(滅少)하였다. 2. 기계이앙시(機械移秧時) 우점잡초(優占雜草)는 올방개-피-올챙이고랭이-물달개비 등의 수생잡초(水生雜草)가 우점(優占)하였으나 건답직파재배(乾畓直播栽培)를 연속(繼續)할 경우 피-바랭이-가막사리-조개풀-자귀풀 등의 습생잡초(濕生雜草)가 우점(優占)하였다. 3. 건답직파(乾畓直播)에 따른 초종(草種)의 다양화(多樣化) 정도(程度)(Simpson Index) 및 군락우점도(群落優占度)(Community dominance)를 보면 기계이앙(機械移秧)의 경우 1-2 초종(草種)이 우점화(優占化)되는 경향(傾向)이었으나 건답직파(乾畓直播)의 경우 여러 초종(草種)이 다양(多樣)하게 분포(分布)되어 있었다. 4. 직파재배(直播栽培)에 따른 연도별(年度別) 유이성(類似性) 계수(係數)(Similarity coefficient)를 보면 직파재배(直播栽培)의 첫해는 41%의 유이성(類似性) 계수(係數)를 나타내 기계이앙(機械移秧)과 상당히 달랐으나 4년간(年間) 연속직파재배(連續直播栽培)를 할 경우 67%로 높아졌다. 5. 건답직파(乾畓直播) 첫해인 1979년도(年度) 잡초방임구(雜草放任區)의 잡초(雜草) 건물중(乾物重)은 $m^2$당 61.3g에 벼 수량(收量)은 290kg/10a이었으나 3년후(年後)인 1992년(年)에는 잡초건물중(雜草乾物重)이 293g/$m^2$으로 1979년에 비해 4.7배가 증가(增加)하였으며 벼 수량(收量)은 전무(全無)였다.

• 한국약용작물학회지
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• 제24권4호
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• pp.277-283
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• 2016

Background: The photosynthetic efficiency cool-season, semi-shade ginseng is normal at low morning temperatures, but drops at high afternoon temperatures. Therefore, optimal plant performance would be ensured if it were possible to control daily light transmission rates (LTR). Methods and Results: Plants were grown in a controlled light environment that replicated 11 AM conditions and comparatively analyzed against plant grown under normal conditions. Growth in the controlled light environment resulted in a 2.81 fold increase in photosynthetic efficiency with no change in chlorophyll content, although LTR were high due to low morning temperatures. Increased aerial plant growth was observed in the ginseng plants adapted to the controlled light environment, which in turn influenced root weight. An 81% increase in fresh root weight (33.3 g per plant on average) was observed in 4-year-old ginseng plants grown in controlled light environment compared to the plants grown following conventional practices (18.4 g per plant on average). With regard to the inorganic composition of leaves of 4-year-old ginseng plants grown in controlled light environment, an increased in Fe content was observed, while Mn and Zn content decreased, and total ginsenoside content of roots increased 2.37 fold. Conclusions: Growth of ginseng under a favorable light environment, such as the condition which exist naturally at 11 AM and are suitable for the plant's photosynthetic activity creates the possibility of large scale production, excellent-quality ginseng.

• 한국작물학회지
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• 제44권4호
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• pp.330-338
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• 1999

Extensive research has been conducted on effects of drought stress on growth and development of soybean but information is rather restricted on the limited-irrigation system by way of precaution against a long-term drought condition in the future. The experiment for limited-irrigation was conducted in transparent vinyl shelter at Asian Vegetable Research and Development Center (AVRDC), Taiwan in 1997. Two soybean varieties, Hwangkeum and AGS292, improved in Korea and AVRDC, respectively were used for this experiment. The relationships between normalized transpiration rate (NTR) and fraction of transpirable soil water (FTSW) in both varieties were similar that the NTR was unchanged until FTSW dropped to about 0.5 or 0.6. At FTSW less than those values, NTR declined rapidly. Days required to harvest in both varieties were significantly prolonged at IR6 treatment compared to any other treatments. Daily mean transpiration rate was significantly higher at IR5 treatment, as averaged over varieties. Similarly, water use efficiency was also high at 1R5 treatment. In both varieties, seed yield was the greatest at the IR5 treatment, as compared to any other limited-irrigation treatments, due to the increased seed number and high transpirational water use efficiency. The indices of input water and seed yield for the different limited-irrigation treatments against control indicated that Hwangkeum produced 59.6% or 60.7% of seed yield using 36.1% or 44.9% of input water, as compared to control, by irrigation at only R5 or R6 stages, respectively. The AGS292 produced 56.1% of seed yield with 35.4% of input water of control, when irrigated at R5 stage. The results of this study have elucidated that the limited irrigation at R5 stage in soybean can be minimized yield loss with such small quantity of water under the environment of long-term drought stress and the expected shortage of agricultural water in the future.

• Asian-Australasian Journal of Animal Sciences
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• 제28권8호
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• pp.1123-1132
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• 2015

Winter wheat is a suitable crop to be ensiled for animal feed and China has the largest planting area of this crop in the world. During the ensiling process, lactic acid bacteria (LAB) play the most important role in the fermentation. We investigated the natural population of LAB in whole-crop wheat (WCW) and examined the quality of whole-crop wheat silage (WCWS) with and without LAB inoculants. Two Lactobacillus plantarum subsp. plantarum strains, Zhengzhou University 1 (ZZU 1) selected from corn and forage and grass 1 (FG 1) from a commercial inoculant, were used as additives. The silages inoculated with LAB strains (ZZU 1 and FG 1) were better preserved than the control, with lower pH values (3.5 and 3.6, respectively) (p<0.05) and higher contents of lactic acid (37.5 and 34.0 g/kg of fresh matter (FM), respectively) (p<0.05) than the control. Sixty LAB strains were isolated from fresh material and WCWS without any LAB inoculation. These LAB strains were divided into the following four genera and six species based on their phenotypic, biochemical and phylogenetic characteristics: Leuconostoc pseudomesenteroides, Leuconostoc citreum, Weissella cibaria, Lactococcus lactis subsp. lactis, Lactobacillus buchneri, and Lactobacillus plantarum subsp. plantarum. However, the prevalent LAB, which was predominantly heterofermentative (66.7%), consisted of Leuconostoc pseudomesenteroides, Leuconostoc citreum, Weissella cibaria, and Lactobacillus buchneri. This study revealed that most of isolated LAB strains from control WCWS were heterofermentative and could not grow well at low pH condition; the selective inoculants of Lactobacillus strains, especially ZZU 1, could improve WCWS quality significantly.