• 한국작물학회지
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• 제29권3호
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• pp.209-217
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• 1984

남부 다모작지대의 도작 증수재배법을 확립하고자 이앙시기를 5월 20일부터 7월 5일까지 15일 간격, 4시기로 하여 수량 형질 및 수량변이를 검토한 결과를 요약하면 다음과 같다. 1. 엽수의 변이는 서광벼에서는 5월 20일 이앙구의 16.2매에 대하여 만식한 7월 5일 이앙구는 15.1매로 1.1매가 적었고 동진벼는 5월 20일 이앙구 14.8매에 대하여 7월 5일 이앙구는 13.1매로 1.7매가 적었다. 2. 지엽단축률은 작기가 늦어짐에 따라 커지는 경향이었다. 3. 작기 이동에 따른 출수일수의 변이는 서광벼는 5월 20일 이앙에서 약 75 일, 6월 5일은 68일, 6월 20일은 67일 정도이었으나, 7월 5일은 71일이 소요되었다. 4. 재배시기에 따른 최대수량은 서광벼는 5월 20일, 동진벼는 6월 20일 이앙이었고 수량생산기의 적산온도와의 관계는 서광벼는 1017$\pm$24$^{\circ}C$에서, 동진벼는 952$\pm$15$^{\circ}C$에서 600kg/10a 이상의 고위수량을 보였다. 5. 단위면적당 수수는 작기가 늦어짐에 따라 직선적으로 감소되는 부의 유의 상관관계(서광벼 r=-0.6768＊＊, 동진벼 r=-0.5182＊＊)가 인정되었다. 6. 작기 이동에 따른 1수 영화수는 서광벼는 작기가 늦어짐에 따라 많아졌고 동진벼는 작기가 빠르거나 늦은 경우 감소경향을 보였다.

• 한국농공학회지
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• 제28권3호
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• pp.79-88
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• 1986

Drought occurs most frequently and severely around transplanting season of the rice plants in Korea. Shortage of water due to drought for the paddy fields often delays transplanting, and less often the rice plants are subjected to water stress after delayed transplanting. The present study aimed at quantification of the rice crop loss due to delayed transplanting, different inten3ity of water stress, and the combined effect of delay in transplanting followed by water stress for better use of limited water for irrigation under drought. The rice variety Chucheong, a japonica, and Nampung, an indica x japonica, were grown, transplanted to 1/200 a plastic pots, and subjected to different timing of transplanting and degree of water stress under a rainfall autosersing, sliding clear plastic roof facility with completely randomized arrangement of 5 replications. The results obtained are summarized as follows: 1.Twelve days or 22 days delay in transplanting without water stress reduced rice yield by 25% and 43% in the japonica variety, and by 15% and 60% in the indica x japonica variety. 2.The 10 days or 20 days water stress developed without irrigation after drainage in the rice plants transplanted at proper time lowered the water potential at the paddy soil 10cm deep to -4 bar, and -12 bar and caused rice yield reduction by 14%, and 45% in the japonica variety and by 8%, and 50% in the indica X japonica variety. 3.The 12 days delay in transplanting and 10 days or 20 days water stress reduced rice yield by 39% and 59% in the japonica variety, and by 38% and 52% in the indica x japonica variety. The 22 days delay in transplanting plus 10 days water stress caused yield reduction by 76%, i.e. meaningless yield, in both varieties. 4.The intermittent irrigation just to wet the soil body for 10 days after 10 days water stress without irrigation increased rece yield by 12 to 16% compared to the rice plants water stessed without irrigation continuously for 20 days in both varieties respectively. 5.The above results suggest strongly 1) to transplant the rice plants at proper .time even with some water stress rather than delay for sufficient water from later rainfall, and 2) to distribute insufficient irrigation water to broader area of transplanted rice with limited irrigation for better use of limited irrigation water. A greater sensitivity of japonica variety to a moderate water stress than the indica X japonica variety during initial rooting and tillering stage was noticed. To cope with frequent drought in rice culture, firstly the lasting time of transplanting without yield reduction should be clarified by region and variety, and secondly a scheme of rational distribution of limited water should be developed by region with better knowledge on the varietal distribution of limited water should be developed by region with better knowledge on the varietal responses to varying intensity of water stress.

• 생물환경조절학회지
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• 제15권1호
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• pp.21-34
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• 2006

This research was conducted to determine the plant growth and nutrient contents of potted chrysanthemum 'Lima Honey' as influenced by application rate of fused superphosphate (FSSP) in three root media, peatmoss+vermiculite (1:1, v/v; PV), peatmoss+composted rice hall (1:1, v/v; PR), and peatmoss+composted pine bark (1:1, v/v; PB). All root media contained polyacrylic acid sodium salt at a rate of $4.5g L^{-1}$. The treatment of $1.4g L^{-1}$ in PV and those of $0.7g L^{-1}$ in PR and PB had the greatest fresh and dry weights in each root medium at both 43 and 80 days after transplanting. Elevated application rates of FSPP increased tissue contents of N, P, and K at both 43 and 80 days after transplanting in PV medium. However, the differences in tissue contents of N, P and K in PR medium were less significant among treatments of FSPP. The pre-planting FSPP also less affected the tissue contents of nutrients at 80 days after transplanting as compared to those at 43 days after transplanting. Elevated application rates of FSPP in PV medium increased EC and the concentrations of $NO_3,\;P_2O_5$, K, Ca, and Mg in soil solution of root media at 43 days after transplanting. The EC in PV medium at 80 days after transplanting was higher than that at 43 days after transplanting. The EC in all root media at 80 days after transplanting was not different among treatments of FSPP.

• 한국작물학회지
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• 제37권3호
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• pp.230-236
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• 1992

이앙기를 달리 하였을 때 어린모와 기계이앙 25일묘, 손이앙 성묘의 묘소질과 본답 생육 차이을 구명하고자 금오벼와 팔공벼 및 동진벼를 공시하여 4월 20일부터 7월 20일까지 15일 간격으로 7회 처리한 결과를 요약하면 다음과 같다. 1. 이앙기별 육묘방법에 따른 묘의 엽수 변화는 손이앙묘>25일묘>어린모 순으로 많았고, 이앙기별로 보면 어린모는 이앙기에 따른 차이가 없었으나, 25일묘는 4월 20일 이앙부터 6월 5일 이앙까지 증가 경향이었으며 그 이후는 근소한 차이를 보였고, 손이앙묘에서 동진벼는 6월 5일까지, 팔공벼와 금오벼는 6월 20일 이앙까지 엽수가 증가하는 경향이었다. 2. $\alpha$-naphthylamine산화력에 의한 근활력과 신근발생량은 어린모>25일묘>손이앙묘 순으로 높았다. 3. 최고분얼기와 유수형성기의 관계는 어린모와 25일묘에서 금오벼는 4월 20일 이앙시 최고분얼기후에 유수가 형성되었으나, 5월 20일부터 7월 5일 이앙까지는 최고분얼기와 같은 시기에, 7월 20일 이앙에서는 최고분얼기 전에 유수가 형성되었다. 한편, 팔공벼는 5월 20일 이앙까지, 동진벼는 7월 5일 이앙까지 최고분얼기 후에 유수가 형성되었다. 4. 어린모와 25일묘의 이앙후 결주율은 이앙기 및 품종에 관계없이 5% 이내로 나타났다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.198-198
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• 2017

Cultivated varieties of sweet potato were from dry texture type to tender texture type on the basis of consumer preferences. There are many differences in the quantity of sweet potato, starch content, pigment, and sugar content depending on the cultivation season and area, even in the same variety. Therefore, in this study, we attempted to establish optimum time of harvesting through growth characteristics and variation in component like starch, sugar, polyphenol and flavonoid. Four sweet potato varieties were used in this experiment. Among them, Jinhongmi (JHM) & Yulmi (YM) were as dry texture type and Pungwonmi (PWM) & Hogammi (HGM) were as tender texture type. Sweet potatoes were transplanted on 23 May, 2016 and were investigated storage root weight and component contents every 20 days from 60 days to 120 days and surveyed yield at 110, 120, 130 days after transplantation. Result revealed that storage root weight of YM, JHM, and HGM were 30.1, 38.9, 20.8 g respectively in 60 days after transplanting. Storage roots of PWM gerw faster with the weight of 88.2 g. In 120 days after transplanting, storage root weight varied from 88.3 to 118.7 g, HGM was the smallest, and PWM was the largest. Sugar contents of sweet potato ranged from 21.0 to $23.8Brix^{\circ}$ in 60 days after transplanting and from 27.5 to $30.78Brix^{\circ}$ in 120 days after transplanting. In particular, the sugar content of HGM was the highest over $30Brix^{\circ}$ after 80 days. The starch content of dry texture type (YM, JHM) increased from 15.5% to 20.4% and tender texture type (PWM, HGM) increased from 11.0% to 17.3%. Starch content tended to be high in dry type sweet potatoes. The content of polyphenol and flavonoid were highest in 60 days after transplanting and was reduced according to cultivation period. The total yield of PWM was high as 3,154 kg/10a and large storage root of over 250 g accounted for 47.4% in 110 days after transplanting. Storage root (YM, JHM, HGM) of 81~150 g accounted for 34.9% ~ 43.2% in 120 days after transplanting. These are the most marketable. Because consumer in Korea prefers small, round and about 100g size sweet potato. The ratio of large storage root (over 250 g) were increased in all varieties at 130 days after transplanting. Therefore, it is considered appropriate to harvest PWM at 110 days and YM, JHM, HGM at 120 days after transplanting, which planted in late May.

• 한국작물학회지
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• 제55권3호
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• pp.259-267
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• 2010

This study was performed at Rice and Winter Cereal Crops Department of NICS during 2007 and 2008 to investigate the characteristics of rice leaf emergence and to obtain basic data which can be used for rice growth simulation model by which we can forecast rice growth stage and heading date accurately under different cultivars, transplanting date, and climatic conditions. To confirm leaf emergence rate according to rice maturing ecotype, we surveyed the leaf emergence rate and heading date of Unkwangbyeo, Hwayoungbyeo and Nampyeongbyeo which are early maturing, medium maturing and medium-late maturing cultivars, respectively, according to seedling raising duration and transplanting time. When seedling duration was 15 days, the growth duration between transplanting time and completion of flag leaf emergence on main culm were 51.5~78.3 days in Unkwangbyeo, 55.3~87.9 days in Hwayoungbyeo and 58.4~98.4 days in Nampyeongbyeo, respectively. When seedling duration was 30 days, they were 50.1~75.5 days in Unkwangbyeo, 52.4~84.7 days in Hwayoungbyeo and 56.4~93.8 days in Nampyeongbyeo, respectively. As transplanting time delayed, the emerged leaf number after transplanting decreased in all rice cultivars. The cumulative temperature between transplanting time to completion of flag leaf elongation on main culm were $1,281^{\circ}C{\sim}1,650^{\circ}C$ in Unkwangbyeo, $1,344^{\circ}C{\sim}1,891^{\circ}C$ in Hwayoungbyeo and $1,454^{\circ}C{\sim}2,173^{\circ}C$ in Nampyeongbyeo, respectively. Leaf emergence rate on main culm were precisely represented by equation, y = $y_0$ + a / [1 + exp( - (x - $x_0$) / b)]^c, when we used daily mean temperature as variable.

• 한국유기농업학회지
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• 제25권2호
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• pp.475-487
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• 2017

친환경 벼 재배농가에서 혼합유박비료를 관행적으로 이앙 3일 전에 사용함에 따라 분얼기 이후에 비료효과가 나타나므로 수량이 감소하는 문제를 해결하기 위해 본 연구를 수행하였다. 실내에서 조사한 혼합유박비료의 무기화는 담수조건에서 7주까지 $NH_4-N$가 증가하였고, 비담수 조건에서 5주까지 $NO_3-N$가 증가하였다. 벼 이앙 20일에 논토양의 질소무기화는 이앙 20일 전 처리구가 0.85%로 가장 높았다. 수확기 토양특성은 혼합유박비료 시비시기에 따라 토양유기물함량을 제외하고 차이가 없었다. 이앙 60일에 초장, 간장, 수장은 이앙 20일 전 처리구가 가장 길었다. 또한 이앙 20일 전 처리구에서 수수, 등숙비율, 천립중이 높게 나타나 백미수량이 관행처리(이앙 3일 전)에 비해 9% 증가하였다. 백미의 백도와 amylose는 차이가 없었지만, 단백질 함량과 식미치는 이앙 20일과 30일전 처리에서 같은 수준이었다. 쌀 수량과 품질 등을 혼합유박비료 시용시기와 관계식으로 산출하면 혼합유박비료의 적정 사용 시기는 이앙 21.3일 전으로 나타났다.

• 한국농공학회논문집
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• 제59권6호
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• pp.39-50
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• 2017

Growth monitoring of highland Kimchi cabbage is very important to respond the fluctuations in supply and demand from middle of August to early September in Korea. For evaluating Kimchi cabbage growth, it needs to classify the transplanting period of Kimchi cabbage, preferentially. This study was conducted to estimate the transplanting period of highland Kimchi cabbage from 2015 to 2016 in the main production area of highland Kimchi cabbage, Anbandegi, Maebongsan, and Gwinemi. Correlation between NDVI (Normalized Difference Vegetation Index) from UAV images and days after transplanting of Kimchi cabbage was high in early transplanting period. But because the growth curve of Kimchi cabbage showed S-type, joint use of multi-temporal linear regression equation for estimation of transplanting period was more suitable. Using application of these equations at Anbandegi, Maebongsan, and Gwinemi, we made the map of transplanting periods of highland Kimchi cabbage. Generally, highland Kimchi cabbage is harvested in sixty days later since transplanting. As a result, we could estimate the harvest time and area of highland Kimchi cabbage.

• 한국작물학회지
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• 제44권2호
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• pp.122-128
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• 1999

Three rice cultivars, Namweonbyeo (early maturing), Hwaseongbyeo (medium maturing) and Dongjinbyeo (medium-late maturing) were trans-planted with 3 different seedling ages to investigate their growth habits and to improve the cultural method in paddy fields in the southern plain area of the Honam region in 1993. The 10-day old seedlings had more vigorous elongation of plant height and higher tillering ability but lower effective tiller rate, when compared with 35-day or 40-day old seedlings. Leaf area index and top dry weight were lower in 10-day old seedlings up to 40 days after transplanting but thereafter, were not different among seedlings ages. CGR was later in 10-day old seedlings, up to 30 days after transplanting, but in 30 to 40 days after transplanting, it was reversed. RGR was the highest in infant seedlings to 40 days after trans-planting, while in 50 days after transplanting, it was reversed. Panicle number and spikelet number per square meter were the highest in 40-day old seedlings, next highest in 35-day old seedlings and the lowest and in adult seedlings up to 40 days after transplanting, while spikelet number per panicle was vice versa. Milled rice yield did not vary significantly by seedling ages, but among the varieties, it was less in Hwaseongbyeo compared with Naweonbyeo and Dongjnbyeo.

• 한국토양비료학회지
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• 제49권5호
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• pp.564-571
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• 2016

As the amount of rice straw collected increases, green manure crops are used to provide the needed organic matter. However, as green manure crops generate methane in the process of decomposition, we tested with different tillage depths in order to reduce the emission. The atmosphere temperature of the chamber was $25{\sim}40^{\circ}C$ during the examination of methane and soil temperature was $2{\sim}10^{\circ}C$ lower than air temperature. The redox potential (Eh) of the soil drastically fell right before irrigated transplanting and showed -300~-400 mV during the cultivating period of rice (7~106 days after transplant). When hairy vetch was incorporated to soil and the field was not irrigated, the generation of methane did not occur from 12 to 4 days before transplanting rice and started after irrigation. Regarding the pattern of methane generation during the cultivation of rice, methane was generated 7 days after transplanting, reached the pinnacle at by 63~74 days after transplanting, rapidly decreased after 86~94 days past transplanting and stopped after 106 days past transplanting. When tested by different soil types, methane emission gradually increased in loam and clay loam during early transplant, whereas it sharply increased in sandy loam. The total amount of methane emitted was highest in sandy loam, followed by loam and clay loam. In all three soil types, methane emission significantly reduced when tillage depth was 20 cm compared to 10 cm. The rice growths and yield were not affected by tillage depth. Therefore, reduction of methane emission could be achieved when application hairy vetch to the soil with tillage depth of 20 cm in paddy soil.