Park, Won;Chung, Mi Nam;Nam, Sang-Sik;Kim, Tae Hwa;Lee, Hyeong-Un;Goh, San;Lee, Im Been;Shin, Woon-Cheol
KOREAN JOURNAL OF CROP SCIENCE
/
v.66
no.2
/
pp.146-154
/
2021
This study was conducted to determine the degree of reduction in the yield of sweetpotato subjected to different shading treatments according to the growing season of the typical viscous sweetpotato 'Hogammi' and the powdery sweetpotato 'Jinyulmi'. Shading was provided using commercially available shading nets (55% and 75% shading level), and the treatments were applied at the following stages of storage root growth: SFS: the storage root formation stage (planting-50th day), SSS: the storage root swelling stage (50-90th day), and SAS: the storage root actively swelling Stage (90-120th day). The growth characteristics according to shading treatments during each growth period, the number of tubers obtained at harvest, and sugar contents were investigated. For both assessed cultivars, there was no significant difference between the control group and the 55% shading treated group with respect to the maximum quantum yield (Fv/Fm) of photosystem II under different shading treatments, whereas the 75% shading group showed slightly higher values than the control group. In both cultivars, the contents of chlorophyll a and b tended to increase in plants subjected to shading treatments compared with the control plants, particularly that of chlorophyll b. Compared with the control group, the chlorophyll b content of 'Hogammi' subjected to 55% and 75% shading increased by 47% and 41%, respectively, whereas that of 'Jinyulmi' increased by 39% and 34%, respectively. We also detected reductions in the dry weights of the above- and belowground parts of the two varieties in response to shading compared with the control, with the reduction in the dry weight of belowground parts being significant. Furthermore, in both varieties, the T/R rate tended to increase in response to shading treatment. Owing to the lack of sunlight, both cultivars tended to suppress the formation and enlargement of tuber roots. Consequently, post-harvest yield analysis revealed that under shading treatments, both cultivars were characterized by poor tuber root growth according to growing season, with the yield of 'Hogammi' showing a greater reduction compared with that of 'Jinyulmi'. In addition, we found that the higher shading level also significantly reduced yields. Compared with the storage root formation and storage root actively swelling stages, shading treatments during the storage root swelling stage significantly affected yield reduction in both varieties.
A simulation study was carried out to delineate potential effects of the lake-induced climate change on crop productivity around Lake Imha which was formed after a multi-purpose dam construction in Andong, Korea. Twenty seven cropping zones were identified within the 30 km by 25 km study area. Five automated weather stations were installed within the study area and operated for five years after the lake formation. A geostatistical method was used to calculate the monthly climatological normals of daily maximum and minimum temperature, solar radiation and precipitation for each cropping zone before and after the dam construction. Daily weather data sets for 30 years were generated for each cropping zone from the monthly normals data representing "No lake" and "After lake" climatic scenarios, respectively. They were fed into crop models (ORYZA1 for rice, SOYGRO for soybean, CERES-maize for corn) to simulate the yield potential of each cropping zone. Calculated daily maximum temperature was higher after the dam construction for the period of October through March and lower for the remaining months except June and July. Decrease in daily minimum temperature was predicted for the period of April through August. Monthly total radiation was predicted to decrease after the lake formation in all the months except February, June, and September and the largest drop was found in winter. But there was no consistent pattern in precipitation change. According to the model calculation, the number of cropping zones which showed a decreased yield potential was 2 for soybean and 6 for corn out of 27 zones with a 10 to 17% yield drop. Little change in yield potential was found at most cropping zones in the case of paddy rice, but interannual variation was predicted to increase after the lake formation. the lake formation.
Korean government has promoted the policy of chemical fertilizer reduction by 40% reduction from 2003 to 2013. Hairy vetch (Vicia villosa Roth) fixes nitrogen from the atmosphere and rye (Secale cerale L.) accumulates soil nitrogen to reduce potential nitrogen loss. The objective of this research was to identify optimum seeding rates of hairy vetch-rye mixtures in the central regions of Korea. The experiment of mixture rate was carried out for maximum production in 2006 and 2007. The best seeding rate mixture for maximum biomass production was 6.75 kg hairy vetch and 5 kg rye per 10a. Pure hairy vetch and rye were used as control. The nitrogen production of mixture treatments were higher than pure rye. The hairy vetch and rye mixture can scavenge potentially leachable nitrogen, while maintaining soil fertility by adding fixed nitrogen to the cropping system.
Herbicidal effects of alachlor to peanuts were observed under different formulations (granule containing 5.0% a.i. and emulsifiable concentrate containing 43.7% a.i.) and levels (granule with 3 and 6kg/l0a and emulsion with 300㏄/l0a) with the transparent polyethylene (P.E.) film mulching. Formulations and levels of alachlor did not affect emergence ratio, time of emergence and flowering, and early growth of peanuts such as the number of leaves and branches, length of branches; and shoot dry weight at 20 and 40 days after planting, but early growth was enhanced by P.E. film mulching. At harvest, weed dry weight was positively correlated with length of branches, but negatively correlated with the number of branches and shoot dry weight. Acalyphu australis and Chenopodium album were not effectively controlled by the application of alachlor and growth of C. album was retarded under P.E. film mulching. Portulaca oleracea and Digitaria sanguinalis were effectively controlled by alachlor, but they were not affected by P.E. film mulching. At harvest, D. sanguinalis, A. australis, and Echinochloa crus galli were predominant weeds in all treatments; persistence of alachlor may not be long enough to control even sensitive weeds to alachlor such as D, sanguinalis in the field of peanuts of which canopy development was relatively slow. Weed dry weight at harvest was negatively correlated with the number of pods and grain yield of peanuts. Among the yield components only the number of nods per plant was positively correlated with grain yield. Hana weeding after July 1 increased grain yield of Peanuts even in alchlor applied plots.
Kim, Jeong-Man;Kim, Ju;Chon, Hyong-Gwon;Park, Eun-Seok;Jeong, Jong-Seong;Choi, Jong-Myung
Horticultural Science & Technology
/
v.28
no.5
/
pp.743-749
/
2010
Objective of this research was to investigate the effect of various potassium concentrations in fertilizer solution on growth of and nutrient uptake by 'Chugyang' eggplant ($Solanum$$melongena$ L.). Tissue analyses were conducted to determine the threshold levels of potassium in plants when disorders develop for potassium. The lower leaves of K deficient plants became spotted, yellowing in color, and finally necrosis occurred. The necrosis spread inward and upward. K toxic plants developed necrotic spot at the margin of old leaves and the surface of old leaves were twisted. The tissue K contents in the most recently fully expanded leaves and dry weight of full above ground plant tissue at 35 days after transplanting showed linear and quadratic response to elevated K concentrations with the equation of y=1.127+0.3147x ($R^2$=0.8916) and y=14.92+2.2743x-$0.1402x_2$ ($R^2$=0.8659). When 10% reduction in dry weight set to threshold levels, optimum tissue K contents are in the range from 2.1 to 5.1%. The yield through 150 days after transplanting and tissue K contents at 150 days after transplanting also showed quadratic and linear responses to elevated potassium concentrations in fertigation solution with the equation of y=153.24+345.5x-$18.46x^2$ ($R^2$=0.8620) and y=0.9921+0.3860x ($R^2$=0.9611), respectively. When the 10% reduction in yield is set to threshold levels, the tissue K contents for maximum yield should be around 3.4% to 5.9% in most recently fully expanded leaves.
The purpose of this study was to investigate the Asynchronous development of young gifted children by parents' perception. Total 3 groups of 145 subjects from age 30 months to 6 years 10 months old young gifted children's parents participated. The major findings were as follows: (1) The mean developmental characteristics was at a high average level. The developmental subscales tended to be high. The level of verbal understanding/expression tended to be high. It reared as followed; intellectual capacity, emotional maturity, visual-motor coordination, morality, self-behavior control, emotion control, physical development, social development, peer relationship, leadership ability. (2) There were significant differences between intellectual capacity, verbal understanding /expression and physical, social development, self-behavior control, emotion control. There were significant differences between physical development, self-behavior control and emotion control as children got lower. There were significant differences between verbal understanding/expression and visual-motor coordination as children got older. There were significant differences between social development, peer relationship and self-behavior control, emotion control as children got older. Also, there were significant differences between leadership ability and self-behavior control, emotion control as children got older. There were significant differences between morality and self-behavior control as children got older. These findings suggested that young gifted children were in the special needs because of the developmental differences.
This experiment was conducted at Cheonan Yonam Experimental Livestock Farm in 2001-2002 to detennine the effect of harvest date(20 April, 26 April and 4 May) on forage yield and quality of rye varieties of three different maturing groups(early maturing variety = ‘Koolgrazer’ midseason maturing variety = ‘Horni122’ and late maturing variety = ‘Danko’). The heading date of Kooigrazer, Hornil22 and Danko were 17, 22 and 29 April, respectively. Dry matter percentage increased from 15.6 to 21.6% as the harvest date was delayed from April 20 to May 4. Among the rye varieties tested, dry matter percentage of Koolgrazer, Hornil22 and Danko were 20.9, 18.8 and 16.3%, respectively. Dry matter yield increased from 1l.2 to 13.9 ton/ha as the harvest date was delayed, but no significant difference among rye varieties. As the harvest date was delayed, total digestible nutrients(TDN) yield also increased significantly from 7.4 to 8.4 ton/ha However no significant difference was found among rye varieties. Crude protein(CP) percentage decreased from 20.3 to 17.1% as the harvest date was delayed, and CP percentage of late maturing variety, Danko, was significantly higher than that of the other varieties. In content of fiber component(NDF, ADF, ADL, hemicellulose and cellulose) of rye, the late harvest date(4 May) showed the highest among harvest dates. From comparisoo within rye varieties tested, Kooigrazer, a early maturing variety had higher than a rnidseason and late maturing varieties, Hornill22 and Danko. The cellulase digestible of organic matter of dry matter(CDOMD) decreased as the harvest date was delayed. Among the rye varieties tested, the CDOMD of a early maturing variety, Koolgrazer was the lowest. Our study differences of winter rye in forage yield and quality resulting from variety maturity and harvest stage. A early maturing variety, Kooigrazer should be harvested between 24 and 28 April, Hamill 22(midseason maturing variety) harvested between 29 April and 3 May, Danko(late maturing variety) harvested between 4 and 8 May for maximum forage yield and optimum quality.
Kim, Chang-Bae;Park, Seon-Do;Park, No-Kwuan;Choi, Dae-Ung;Son, Sam-Gon
Korean Journal of Soil Science and Fertilizer
/
v.20
no.2
/
pp.161-168
/
1987
This study was conducted to evaluate the effects of potassium and sulfur power levels on the growth, nutrients' uptake at different growing stage and seed yield of peanut plant and changes of soil chamical properties in a sandy peanut cultivated soil of Nak-dong riverside in 1984. 1. The length of main stem, that of branch NO. and NO. of branches per plant were increased by the increased application of potassium and sulfur powdar. Especially sulfur powder treated plot were shown in positive effect with obtained in main root length, NO. of roots and Wt. of noudles formed per plant, roots' weight of peanut plant was much more than top's Wt. at harvesting stage, and so ratio of dry matter Wt. top/root was low. 2. The noudle's Wt. formed was positively significant recognized with dry matter Wt. of peanut plant at harvesting stage and the treatments of potassium were increased 7-20% compared with potassium non-treated plot and sulfur's treatments were increased 4-13% than that of potassium 15kg/10a treatment which was sulfur's non-treated plot in seed yield. 3. Relationship between all nutrients' uptake at flowering stage and seed yield were positively significant recognized, but $P_2O_5$ uptake and N/S ratio showed negative effect at harvesting stage of peanut plant. 4. By the increase of potassium and sulfur powder application, the soil pH at two different stages were almost not differential and the content of K, $P_2O$ and $SO_4$ in soil and $SO_4/P_2O_5$ ratio were increasing tendency.
Park, Seong-Tae;Kim, Soon-Chul;Choi, Choong-Don;Lee, Soo-Kwan
KOREAN JOURNAL OF CROP SCIENCE
/
v.30
no.3
/
pp.252-258
/
1985
An experiment was conducted at the Yeongnam Crop Experiment Station to obtain basic informations about cultural techniques for high yielding by manipulating plant spacing using two rice cultivars, Samgangbyeo (Indica/Japonica type) and Nakdongbyeo (Japonica type), and four plant spacings, 10${\times}$10cm, 20${\times}$20cm 30${\times}$30cm and 40${\times}$40cm, with 4 kinds of seedling number per hill, 1,3,5 and 7, respectively. High photosynthetic efficiency (Eu) exhibited at the Samgangbyeo compared to Nakdongbyeo regardless of plant spacings and seedling numbers. For Samgangbyeo, Eu value was the highest at the 20${\times}$20cm plant spacing and five seedlings and seven seedlings per hill showed high Eu values at 10${\times}$10cm plant spacing and 20${\times}$20cm plant spacing, respectively, while other plant spacings were not significantly differed among seedling numbers. For Nakdongbyeo, however, one seedling plot obtained high Eu value at the 10${\times}$10cm plant spacing while this Eu value increased as the seedling number per hill increased in other plant spacings. There was a high positive correlation between rice grain yield and total competition index for both cultivars while kind of relationships differed in these two cultivars; linear relationship for Samgangbyeo and exponential relationship for Nakdongbyeo, respectively. Competition index between rice hill was more significant than within rice hill for Samgangbyeo while both competition indexs were important for Nakdongbyeo to increase rice yield.
This study was conducted to get basic information of dry matter production and agronomic characteristics for increasing grain ripening in rice cultivar with large grains. Three cultivars which have different grain size were used. Of the two large grain cultivars, SR7796-3-1-5-1-l(SR7796F$_{7}$) had long culm and SR11269-13-3-4-2(SR11269F$_{6}$) had short culm. On the other hand, Tamjinbyeo was recommended cultivar had medium size of grain and culm. LAI was highest in Tamjinbyeo, followed by the SR11269F$_{6}$ and SR7796F$_{7}$, LAI decrement was higher in large grain cultivars than that of Tamjinbyeo after 20days after heading. Total dry weight(TDW) of areal part was highest in SR11269F$_{6}$, followed by the Tamjinbyeo and SR7796F$_{7}$. Dry weight (DW) of stem (leaf sheath+culm) at harvesting stage was decreased 15%, 12% in Tamjinbyeo, SR11269F$_{6}$, respectively, but was increased 5% in SR7796F$_{7}$ compared to heading stage. In distribution rate of each organ to TDW, distribution rate of leaf blade was low in large grain cultivar, but that of stem in Tamjinbyeo, SR7796F$_{7}$ and SR11269F$_{6}$ was 36%, 38% and 42%, respectively. In canopy architecture leaf blade weight was the highest 30~40cm, 40~50cm and 70~8Ocm above the ground in SR11269F$_{6}$, Tamjinbyeo and SR7796F$_{7}$, respectively. Range of panicle distribution in the canopy was 40cm in Tamjinbyeo, and was 70cm in large-grain cultivars. The results suggest that it has to take a growing interest in developing culture method for increasing LAI during growth stage, especially, around heading, in keeping green leaf till ripening stage and also in growing unformly plant within rice hill in large grain cultivars.cultivars.ltivars.
본 웹사이트에 게시된 이메일 주소가 전자우편 수집 프로그램이나
그 밖의 기술적 장치를 이용하여 무단으로 수집되는 것을 거부하며,
이를 위반시 정보통신망법에 의해 형사 처벌됨을 유념하시기 바랍니다.
[게시일 2004년 10월 1일]
이용약관
제 1 장 총칙
제 1 조 (목적)
이 이용약관은 KoreaScience 홈페이지(이하 “당 사이트”)에서 제공하는 인터넷 서비스(이하 '서비스')의 가입조건 및 이용에 관한 제반 사항과 기타 필요한 사항을 구체적으로 규정함을 목적으로 합니다.
제 2 조 (용어의 정의)
① "이용자"라 함은 당 사이트에 접속하여 이 약관에 따라 당 사이트가 제공하는 서비스를 받는 회원 및 비회원을
말합니다.
② "회원"이라 함은 서비스를 이용하기 위하여 당 사이트에 개인정보를 제공하여 아이디(ID)와 비밀번호를 부여
받은 자를 말합니다.
③ "회원 아이디(ID)"라 함은 회원의 식별 및 서비스 이용을 위하여 자신이 선정한 문자 및 숫자의 조합을
말합니다.
④ "비밀번호(패스워드)"라 함은 회원이 자신의 비밀보호를 위하여 선정한 문자 및 숫자의 조합을 말합니다.
제 3 조 (이용약관의 효력 및 변경)
① 이 약관은 당 사이트에 게시하거나 기타의 방법으로 회원에게 공지함으로써 효력이 발생합니다.
② 당 사이트는 이 약관을 개정할 경우에 적용일자 및 개정사유를 명시하여 현행 약관과 함께 당 사이트의
초기화면에 그 적용일자 7일 이전부터 적용일자 전일까지 공지합니다. 다만, 회원에게 불리하게 약관내용을
변경하는 경우에는 최소한 30일 이상의 사전 유예기간을 두고 공지합니다. 이 경우 당 사이트는 개정 전
내용과 개정 후 내용을 명확하게 비교하여 이용자가 알기 쉽도록 표시합니다.
제 4 조(약관 외 준칙)
① 이 약관은 당 사이트가 제공하는 서비스에 관한 이용안내와 함께 적용됩니다.
② 이 약관에 명시되지 아니한 사항은 관계법령의 규정이 적용됩니다.
제 2 장 이용계약의 체결
제 5 조 (이용계약의 성립 등)
① 이용계약은 이용고객이 당 사이트가 정한 약관에 「동의합니다」를 선택하고, 당 사이트가 정한
온라인신청양식을 작성하여 서비스 이용을 신청한 후, 당 사이트가 이를 승낙함으로써 성립합니다.
② 제1항의 승낙은 당 사이트가 제공하는 과학기술정보검색, 맞춤정보, 서지정보 등 다른 서비스의 이용승낙을
포함합니다.
제 6 조 (회원가입)
서비스를 이용하고자 하는 고객은 당 사이트에서 정한 회원가입양식에 개인정보를 기재하여 가입을 하여야 합니다.
제 7 조 (개인정보의 보호 및 사용)
당 사이트는 관계법령이 정하는 바에 따라 회원 등록정보를 포함한 회원의 개인정보를 보호하기 위해 노력합니다. 회원 개인정보의 보호 및 사용에 대해서는 관련법령 및 당 사이트의 개인정보 보호정책이 적용됩니다.
제 8 조 (이용 신청의 승낙과 제한)
① 당 사이트는 제6조의 규정에 의한 이용신청고객에 대하여 서비스 이용을 승낙합니다.
② 당 사이트는 아래사항에 해당하는 경우에 대해서 승낙하지 아니 합니다.
- 이용계약 신청서의 내용을 허위로 기재한 경우
- 기타 규정한 제반사항을 위반하며 신청하는 경우
제 9 조 (회원 ID 부여 및 변경 등)
① 당 사이트는 이용고객에 대하여 약관에 정하는 바에 따라 자신이 선정한 회원 ID를 부여합니다.
② 회원 ID는 원칙적으로 변경이 불가하며 부득이한 사유로 인하여 변경 하고자 하는 경우에는 해당 ID를
해지하고 재가입해야 합니다.
③ 기타 회원 개인정보 관리 및 변경 등에 관한 사항은 서비스별 안내에 정하는 바에 의합니다.
제 3 장 계약 당사자의 의무
제 10 조 (KISTI의 의무)
① 당 사이트는 이용고객이 희망한 서비스 제공 개시일에 특별한 사정이 없는 한 서비스를 이용할 수 있도록
하여야 합니다.
② 당 사이트는 개인정보 보호를 위해 보안시스템을 구축하며 개인정보 보호정책을 공시하고 준수합니다.
③ 당 사이트는 회원으로부터 제기되는 의견이나 불만이 정당하다고 객관적으로 인정될 경우에는 적절한 절차를
거쳐 즉시 처리하여야 합니다. 다만, 즉시 처리가 곤란한 경우는 회원에게 그 사유와 처리일정을 통보하여야
합니다.
제 11 조 (회원의 의무)
① 이용자는 회원가입 신청 또는 회원정보 변경 시 실명으로 모든 사항을 사실에 근거하여 작성하여야 하며,
허위 또는 타인의 정보를 등록할 경우 일체의 권리를 주장할 수 없습니다.
② 당 사이트가 관계법령 및 개인정보 보호정책에 의거하여 그 책임을 지는 경우를 제외하고 회원에게 부여된
ID의 비밀번호 관리소홀, 부정사용에 의하여 발생하는 모든 결과에 대한 책임은 회원에게 있습니다.
③ 회원은 당 사이트 및 제 3자의 지적 재산권을 침해해서는 안 됩니다.
제 4 장 서비스의 이용
제 12 조 (서비스 이용 시간)
① 서비스 이용은 당 사이트의 업무상 또는 기술상 특별한 지장이 없는 한 연중무휴, 1일 24시간 운영을
원칙으로 합니다. 단, 당 사이트는 시스템 정기점검, 증설 및 교체를 위해 당 사이트가 정한 날이나 시간에
서비스를 일시 중단할 수 있으며, 예정되어 있는 작업으로 인한 서비스 일시중단은 당 사이트 홈페이지를
통해 사전에 공지합니다.
② 당 사이트는 서비스를 특정범위로 분할하여 각 범위별로 이용가능시간을 별도로 지정할 수 있습니다. 다만
이 경우 그 내용을 공지합니다.
제 13 조 (홈페이지 저작권)
① NDSL에서 제공하는 모든 저작물의 저작권은 원저작자에게 있으며, KISTI는 복제/배포/전송권을 확보하고
있습니다.
② NDSL에서 제공하는 콘텐츠를 상업적 및 기타 영리목적으로 복제/배포/전송할 경우 사전에 KISTI의 허락을
받아야 합니다.
③ NDSL에서 제공하는 콘텐츠를 보도, 비평, 교육, 연구 등을 위하여 정당한 범위 안에서 공정한 관행에
합치되게 인용할 수 있습니다.
④ NDSL에서 제공하는 콘텐츠를 무단 복제, 전송, 배포 기타 저작권법에 위반되는 방법으로 이용할 경우
저작권법 제136조에 따라 5년 이하의 징역 또는 5천만 원 이하의 벌금에 처해질 수 있습니다.
제 14 조 (유료서비스)
① 당 사이트 및 협력기관이 정한 유료서비스(원문복사 등)는 별도로 정해진 바에 따르며, 변경사항은 시행 전에
당 사이트 홈페이지를 통하여 회원에게 공지합니다.
② 유료서비스를 이용하려는 회원은 정해진 요금체계에 따라 요금을 납부해야 합니다.
제 5 장 계약 해지 및 이용 제한
제 15 조 (계약 해지)
회원이 이용계약을 해지하고자 하는 때에는 [가입해지] 메뉴를 이용해 직접 해지해야 합니다.
제 16 조 (서비스 이용제한)
① 당 사이트는 회원이 서비스 이용내용에 있어서 본 약관 제 11조 내용을 위반하거나, 다음 각 호에 해당하는
경우 서비스 이용을 제한할 수 있습니다.
- 2년 이상 서비스를 이용한 적이 없는 경우
- 기타 정상적인 서비스 운영에 방해가 될 경우
② 상기 이용제한 규정에 따라 서비스를 이용하는 회원에게 서비스 이용에 대하여 별도 공지 없이 서비스 이용의
일시정지, 이용계약 해지 할 수 있습니다.
제 17 조 (전자우편주소 수집 금지)
회원은 전자우편주소 추출기 등을 이용하여 전자우편주소를 수집 또는 제3자에게 제공할 수 없습니다.
제 6 장 손해배상 및 기타사항
제 18 조 (손해배상)
당 사이트는 무료로 제공되는 서비스와 관련하여 회원에게 어떠한 손해가 발생하더라도 당 사이트가 고의 또는 과실로 인한 손해발생을 제외하고는 이에 대하여 책임을 부담하지 아니합니다.
제 19 조 (관할 법원)
서비스 이용으로 발생한 분쟁에 대해 소송이 제기되는 경우 민사 소송법상의 관할 법원에 제기합니다.
[부 칙]
1. (시행일) 이 약관은 2016년 9월 5일부터 적용되며, 종전 약관은 본 약관으로 대체되며, 개정된 약관의 적용일 이전 가입자도 개정된 약관의 적용을 받습니다.