우리나라는 무기질비료 사용량이 많은 나라 중 하나이다. 그러나 1980년 이후 지속가능농업에 대한 필요성에 의해 1997년 친환경 농업육성법이 제정되었고 지속가능한 농업을 위한 연구로 논, 밭, 시설 및 과수에 대한 비료사용실태조사가 실시되고 있다. 이에 본 연구는 과수 중 대표되는 7작물(배, 포도, 사과, 복숭아, 대추, 단감, 키위)을 대상으로 각 도에서 805농가를 선정하여 실시하였으며, 조사내용은 사용하는 비료의 종류, 사용량 등에 대해 농가를 방문하여 면접 청취조사하였다. 국내 과수작물의 성분별 평균 비료사용량(N-P2O5-K2O)은 30.0-23.8-24.3 kg 10a-1이었으 며 비료 종류별로 구분하였을 때 퇴비 > 유기질비료 > 무기질비료 순으로 사용하고 있었다. 단위면적당 가장 많은 비료를 사용하고 있는 과수는 대추로 질소, 인산 및 칼리를 평균 53.3-42.0-49.5 kg 10a-1을 사용하고 있는 것으로 확인되었다. 앞으로 지속가능 농업과 농업환경의 보전을 위해서는 농가에서 사용하는 비료의 장기간 모니터링 뿐만 아니라 농업인에게 무기질비료, 유기질비료 및 퇴비의 적정사용방법에 대한 교육 및 홍보를 지속적으로 실시해야 될 것으로 판단된다.

거베라의 조직배양과정 중 증식배양단계에서 LEDs 파장이 기내배양묘의 생육에 미치는 영향을 조사하고 자 이 실험을 수행하였다. 절화용 거베라 ‘바네사’의 증식배양 시 발광다이오드(LEDs) 광질에 따른 생육특 성을 보면 주당 신초수가 red와 red(4) + blue(1) LEDs에서 대조구인 형광등에 비해 많았고 far-red에서 는 다소 증가 또는 blue LEDs에서는 줄어드는 경향이 었으나 그 차이는 통계적 유의성이 없었다. 초장은 red LEDs에서 가장 길었으며 주당 엽수는 red(4) + blue(1) LEDs에서 가장 많았고 엽면적은 far-red LEDs를 제외 하고는 비슷한 경향이었다. 주당 생체중과 건물중은 red LEDs에서 가장 무거웠으나 red(4) + blue(1) LEDs, 형광 등과도 큰 차이가 없었다. 증식배양단계에서 가장 중요 한 것은 신초를 확보하는 것으로 다른 생육특성들이 형 광등 대비 큰 차이가 없는 것으로 보아 red LEDs 또 는 red(4) + blue(1) 혼합 LEDs를 광원으로 사용하는 것이 적당하다고 판단된다.

거베라의 동계 약광기 생산성 향상을 위하여 보광처 리가 광합성과 수량에 미치는 영향을 검토한 결과는 다음과 같다. 광원별 보광처리에 의해 절화수량은 48- 58%, 광합성률은 15-200% 증가하였으며 특히 고압나 트륨등과 메탈할라이드등이 광합성률이 높고 보광등의 발열로 인한 환경개선 효과가 높아 적합한 보광용 광 원으로 나타났다. 한편 전력사용량이 증가할수록 무처 리에 비해 수량이 증가하고 절화품질이 향상되는 경향 이었으나 절화수량 증가와 난방효과와 같은 이익적인 요소에 비해 설치비용, 전기요금 등의 손실적인 요소들 이 더 발생하여 30kW • 10a-1 수준의 보광이 적합한 보광시설 설치 기준으로 판단되었다.

본 연구는 기내에서 재생된 오리엔탈나리 ‘Casa Blanca’ 와 ‘Siberia’ 소인경의 새로운 휴면 타파방법을 모색하고 자 생장조절물질을 첨가한 온탕처리 조건을 검토하였다. 오리엔탈나리 ‘Casa Blanca’와 ‘Siberia’ 두 품종 모두 30oC 증류수, 120분 온탕처리에서 맹아소요일수는 단축되 었으나 맹아율이 낮았다. GA4+7 100mg·L−1용액을 35oC 에서 1시간 온탕 처리에 의해서 ‘Casa Blanca’와 ‘Siberia’의 맹아율은 각각 76.7%으로 크게 촉진되었고 정식 2년차의 생장과 구근 비대가 촉진되었으며, 휴면에 따른 호흡정도를 반영하는 미토콘드리아 단백질 함량과 fumarase 활성도 높아 휴면타파의 생리적 원인도 구명 하였다. 생장조절물질(GA4+7)을 첨가한 온탕처리에 의해 기내에서 재생된 오리엔탈나리 소인경의 휴면을 효과 적으로 타파할 수 있었다.

새롭게 도입된 얌빈의 국내 재배기술 확립을 위하여 육묘조건, 적심, 적화, 재식밀도 등의 재배요인에 의한 생장과 수량반응을 조사한 결과는 다음과 같다. 얌빈은 P.E. 하우스내에 전열 온상을 설치하여 평균 22℃로 유지하여 30일(적산온도 650℃) 육묘하면 건전묘 생산이 가능하였다. 트레이 규격에 따른 출현 특성의 차이는 없으며, 셀 크기가 클수록 묘 생장량이 증가하지만 육묘효율, 이식작업의 편의성을 고려하여 128공 트레이가 적합하였다. 7월 하순에서 8월 상순에 120 ㎝ 높이에서 적심을 하면 수량이 23% 가량 많아지며 8월 하순에서 9월 상순 사이에 적화를 하면 괴경수와 괴경중이 증가하여 수량이 32% 가량 많아진다. 50 ㎝×30 ㎝로 정식하였을 때 관행 100 ㎝×30 ㎝보다 수량이 30% 증가하였다. 적심, 적화, 재식밀도 최적조합처리는 무처리에 비해 경제적으로 107%의 이익적인 요소가 발생하였다. 이상의 연구 결과 얌빈의 최적 재배기술 적용을 통해 국내에서 새로운 소득 작목으로서 유망할 것으로 판단된다.

Background: The leaf temperature (TLEAF) is one of the most important physical parameters governing water and carbon flux, including evapotranspiration, photosynthesis and respiration. Cnidium officinale is one of the important folk medicines for counteracting a variety of diseases, and is particularly used as a traditional medicinal crop in the treatment of female genital inflammatory diseases. In this study, we developed a model to estimate TLeaf of Cnidium officinale Makino based on black globe temperature (TBGT). Methods and Results: This study was performed from April to July 2018 in field characterized by a valley and alluvial fan topography. Databases of TLEAF were curated by infrared thermometry, along with meteorological instruments, including a thermometer, a pyranometer, and an anemometer. Linear regression analysis and Student’s t-test were performed to evaluate the performance of the model and significance of the parameters. The correlation coefficient between observed TLEAF and calculated TBGT obtained using an equation, developed to predict TLEAF based on TBGT was very high (r2 = 0.9500, p < 0.0001). There was a positive relationship between TBGT and solar radiation (r2 = 0.8556, p < 0.0001), but a negative relationship between TBGT and wind speed (r2 = 0.9707, p < 0.0001). These results imply that heat exchange in leaves seems to be mainly controlled by solar radiation and wind speed. The correlation coefficient between actual and estimated TBGT was 0.9710 (p < 0.0001). Conclusions: The developed model can be used to accurately estimate the TLeaf of Cnidium officinale Makino and has the potential to become a practical alternative to assessing cold and heat stress.

Background : Angelica tenuissima Nakai is a major medicinal plant around GyeoungBuk Area. Powdery mildew of Angelica tenuissima Nakai caused a Erysiphe heraclei DC. is a major disease. It was found leaf of Angelica tenuissima after rainy season. There was no agicultural chemical registration on Angelica tenuissima. Ecofriendly control needs Angelica tenuissima for GAP. Methods and Results : The seedlings used for the test were sowed and cultivated in mid-February at Bonghwa herbal crop research institute. The irrigation water was irrigated through a drip irrigation system. Powdery mildew occurred after rainfall lasted more than 2 days at the end of June. The pathogen (Erysiphe heraclei DC.) was identified by observing the diseased plants with an optical microscope. Bordeaux mixture was tested using Gold Bordeaux which was listed in the eco-friendly material list and the magnification was 500 times for the medicinal efficacy test and 250 times for the damage test. For the chemical treatment 40 ㎖ of Bordeaux mixture was added to 20 ℓ of water to prepare 500 times of the solution and the treatment was sufficiently wetted to the plant at about 8:00 am. The first treatment was treated at 7. 5 days, the second treatment at 7. 13 days, the third treatment at 7. 26 days, and the final investigation at 7.26 days. The occurrence of powdery mildew was sufficient to evaluate the treatment effect at 13.0% in untreated control and the control value was low at 33.5% in one treatment but 74.0% in control after 2 treatments showed significant control effect. 89.2% respectively. As a result it is effective to control the powdery mildew of Bordeaux solution at least once every seven days to improve the control effect. Conclusion : Control value of bordeaux mixture was higher than after two times of treatment. Bordeaux mixture treatment of powdery mildew on Angelica tenuissima control 89.2% and it can use a producing ecofriendly agricultural product.

Background : Angelica dahurica, Ligusticum sinense and Ledebouriella seseloides are cultivated in small areas in Korea. Domestic cultivation area is around 10 ha, and cultivated varieties have not been developed yet. Therefore, the quality of the product is not uniform, and industrialization is difficult. Lately, studies on the development of varieties have been carried out using domestic collecting germplasm. Methods and Results : Germplasm was collected in Gangwon-do, Chungcheongbuk-do, Gyeongsangbuk-do, Jeollanam-do and Jeju-do and sowed in pots in March 2017. Angelica dahurica was used the collected in Gyeongsangbuk-do, Jeollanam-do, Ligusticum sinense was used the collected in Gangwon-do and Gyeongbuk-do and Ledebouriella seseloides was used the collected Jeju-do. In May of 2017, those were planted and the stem and leaf characteristics were compared and analyzed 1-year. It was bloomed in the second years of 2018, and stem, leaf and flowering characteristics were compared and analyzed. In the first year of growth characteristics, Angelica dahurica showed lower leaf and stem growth in Jeollanam-do collected germplasm. However, there was no statistical significance. Growth characteristics of Ligusticum sinense were higher in Gangwon-do collection than in Gyeongsangbuk-do, but there was no statistical significance. Ledebouriella seseloides was no significant difference between the groups in Jeju-do. In the second years, individual selection were carried out for popullation improvement. The Angelica dahurica showed green and purple stalks and the collected germplasm of Jeollanam-do showed relatively low growth. Ligusticum sinense and Ledebouriella seseloides were no significant differences in growth and color between stem and leaf, stem and stem Conclusion : All three crops were cross pollination, and collected open pollination. Therefore, there were many segregation by germplasm and genetic variation was large. Furthermore, it is considered that statistical significance does not appear. If genetic uniformity is increased through continuous selection and population improvement, it will be possible to cultivate varieties using germplasm. Genetic variation will be a good source of genetic resources.

Background : Polygala tenuifolia is mainly distributed in Korea and China. It is known to be mainly helpful for brain function and has been used medicinally for a long time. Currently, most of that used in domestic are imported from China. We want to identify the basic characteristics to replace imports and grow into new domestic income crops. Previous studies have examined the storage conditions of seeds and the areas suitable for cultivation. In this study, seed harvesting, germination conditions and seedling production methods are explained. Methods and Results : Seed harvest method - in early June, we have covered the funnel, paper bag and mesh bag. Seed harvested at the end of June were sorted by wind speed of 3.5 m/s – 6.1 m/s and 1 ㎜ - 4 ㎜ mesh size. The germination rate was measured at 20℃ for 10 days. Suit of the germination temperature - the germination rate was measured by 100 seeds, three replicates with a temperature gradient of 15℃ to 35℃ and 2℃ intervals. In order to confirm the conditions for seedling production, the emergence rate was examined at 20℃, 25℃, 30℃ and 35℃ in growth chamber. The seed harvesting method was 1.88 g of mesh bag the highest yield. The best sorting method was 2 ㎜ mesh size and 5.7 m/s wind speed. The germination temperature was the highest at 89.7 - 90.3% at the temperature range of 1 9℃ - 20℃ and the germination rate was decreased to 21.0% at 27℃. The seedling production rate was highest at 20℃. There was no difference in growth according to the pot size, but the survival rate was the highest in 105 size Conclusion : As a result of this study, Polygala tenuifolia was confirmed that harvesting by mesh bag and sorting by size and wind speed were effective for seed quality and yield. The seed germination was observed at relatively low temperature. These results can be used as basic data for cultivation.

Background : Due to changes in climate and cultivation conditions, the growth monitoring is an essential factor in improving crop productivity. With the recent development of image analysis technology incorporating ICT, it has become possible to constantly monitor the crop growth. As a medicinal crop specialized in Gyeongsangbuk-do, Korea, Cnidium officinale Makino was examined for the possibility of growth diagnosis through image analysis for stable production. Methods and Results : The IP camera was installed at 2.5 m height in experiment field. The RGB image of every 06:00 was captured from July 1 to July 30 and used for analysis. The captured images were analyzed using the image analysis tool, Image J. The greeness was estimated by the average value of the green histogram. The canopy size was determined by the color range (red: 0-255, green: mean value-255, blue: 0-255) and was calculated as the ratio of pixels number of the entire image to those of the selected area. The growth temperature during investigation period was measured by Hobo MX2300. High temperature, excess of 28℃, was compared to stress response such as decrement of canopy size. The greeness and the canopy size are respectively represented by the quadratic function greeness = -0.0722GD2 + 6248.9GD – 1e + 08 (GD, growing day; R2 = 0.46) and canopy size = -0.0462GD2 + 3996.7GD – 9e + 07 (R2 = 0.93). From July 11, it began to exceed the growth limit temperature of 28℃, and the canopy size began to decrease from this period. Between the canopy size (C) and the accumulated temperature exceeding 28℃, there was a negative correlation, C = -0.13ATEC + 56.75 (R2 = 0.87) during the decreasing period. Conclusion : Extraction of color information in Cnidium officinale Makino using RGB image should be preceded by standardized setting, but it is considered to be useful tool for analyzing the change of quantitative characteristics over time. In the future, it is necessary to make a comparative study with the actual growth rate in the image diagnosis.

Background : Saliva miltiorrhiza is a perennial medicinal crop of Lamiaceae and has been reported to have various functionalities such as improvement of cardiovascular function and antihypertensive. However, domestic cultivation technique in Korea has not been established yet. Seed production system is required to increase propagation efficiency and to establish breeding basis for stable production. This experiment was carried out to determine the optimal date of the S. miltiorrhiza. Methods and Results : S. miltiorrhiza was seeded in April of 2017 and 2018. The seeds were harvested at 5-day intervals based on the flowering period of 2018. Number of peduncles, flowers, and seeds were investigated at each period. And germination rate was also investigated. The optimum seed harvest time was estimated by relationship between the seed production and days after flowering period (DAF) or cumulative temperature. The flowering rate and amount of seed of 2-years plant was higher than 1-year plant. As DAF increased, number of flowers, fertility rate, and the amount of seeds increased. At 20 DAF, 1-year, and 2-years plant respectively produced 2.2 g and 25.2 g of seed. Seed production (SP) and DAF or accumulated temperature (AT) had a quadratic relation, SP (g) = -0.1052DAF2 + 3.7396DAF - 12.347 (R2 = 0.828) and SP (g) = -0.0002AC2 + 0.1727AC - 9.146 (R2 = 0.853). The maximum amount of seed was estimated to be 20.9 g at 17.8 DAF or 21.3 g at 353℃. The seed germination rate was increased until 20 DAF with 62.0%. The amount of seed and germination rate were decreased at 25 DAF. Conclusion : The seeds of S. miltiorrhiza can be produced the highest amount with high viability on the 18th day after flowering period in 2-years after planting.

Background : It is necessary to develop a diagnostic tool for the precision agriculture according to the change of agriculture environment. In particular, medicinal crops are often cultivated in poor areas such as mountains and valleys, and are susceptible to abnormal climates. Therefore, there is a need for a method that can diagnose the growth easily and with time. We conducted a study to investigate the possibility of remote sensing for 10 species of medicinal crops using unmanned aerial vehicles and multispectral images. Methods and Results : This study was conducted in 0 - 4 times continuously cultivated field with 10 species of medicinal crops (Angelica gigas, A. koreana, A. tenuissiman, A. dahurica, A. acutiloba, A. polymorpha, Ledebouriella seseloides, Lithospermum erythrorhizon, Rhemannia glutinosa). Growth characteristics such as plant height, number of leaves, leaf length, leaf width, stem diamanter and number of stems were investigated between July 10 and July 16. The reflectance map of red (660 ㎚) and NIR (790 ㎚) was obtained using a UAV equipped with a multi-spectral sensor and NDVI [Normalized Difference Vegetation Index] was obtained with a Pix4D mapper. As the number of times of continuos cultivation increased, the growth and NDVI tend to decreased. 6 species of Angelica genus were positively correlated with growth characteristics such as plant height, leaf length, leaf width, and stem diameter and NDVI. Otherwise, there was no significant relationship between growth characteristics and NDVI in Ledebouriella seseloides, Lithospermum erythrorhizon, and Rhemannia glutinosa. This is because the difference in the growth according to time of continuos cultivation was not significant and the canopy structure tended to overlap with the upper and lower leaves. Conclusion : NDVI is widely used as a useful tool for evaluating the canopy productivity and is highly correlated with the above-ground growth characteristics of 6 species of Angelica spp. It is necessary to develop the growth index suitable for the each species and to enhance the validity of growth index by examining the correlation under various cultivation conditions.

Background : The continuous cropping of Cnidium officinale is a serious problem for the cultivation practices, which is an unelucidated subject. This study is concerned mainly with rhizosphere microbiome and meteological factors on the cause of physiological damage in the continuous cropping of Cnidium officinale. Methods and Results : Microbial population and community dynamics was evaluated with metagenomic DNA by IonTorrent PGM. Results of HPLC profiling revealed that metabolic components of symbiotic interaction with Cnidium officinale was not detected in cultivated soils. Proteobacteria groups such as nitrogen fixing bacteria, Pseudomonas and Burkholderia of rhizosphere soil in continuous cropped fields mainly decreased compared to the first cropped soil. Principle component analysis of bacterial community showed a significantly differentiated vector between first cropping field and continuous cropped fields. Although growth characteristics including height, leaf length, leaf diameter amd stem diameter etc., was not different with continuous cultivation year until mid-July, physiological damage was dramatically started from late July. Yield of Rhizoma in continuous cropped fields significantly decreased compared to first cropped field. Evapotranspiration of Cnidium officinale with lysimeter for summer season was evaluated. It showed high relationship between solar radiation and evapotranspiration with R2 = 0.7778 and 41% of solar radiation converted into evapotranspiration during 16 days. This result imply that evapotranspiration is mainly controlled by radiation energy in clear days. Water and heat cycle through evapotranspiration is suppose to be one of the important factors related with physiological disorder of Cnidium officinale. Conclusion : This result imply that physiological damage resulted from continuous cropping is involved in decrease of Proteobacteria at rhizosphere soils under stressed conditions.

Amaranth (Amaranth caudatus) is attracting attention as a preference crop in Gyeongsangbuk-do province. To determine its growth potential and cultivation requirements, we investigated its growth characteristics, dry matter productivity, and grain yield according to the growing period. Growth and dry matter productivity were significantly higher for plants that were sown on May 10th when the temperature was the highest, whereas the yield was significantly higher for plants that were sown on April 10th. Amaranth grain yield ranged from 96 to 243 kg according to the sowing date and cultivation year. The optimum harvest time for plants that were sown on April 10th, May 10th, and June 10th were 120, 110, and 110 days after seeding, respectively. The mean temperature and growing period had a significant quadratic function with yield. Based on these equations, the optimum growing temperature was estimated as 20.6℃ and the optimum growing period as 104-119 days after seeding.

Background : Heat stress induced from high temperature are known to crucially affecting on physiological properties and yield in Cnidium officinale. Methods and Results : The effect of foliar application of mixture including a urea, ascorbic acid and calcium chloride on high temperature injury of Cnidium officinale. Photosynthesis and leaf temperature in Cnidium officinale were investigated after cultivating for 24 hours at 35℃. Net photosyntheis rate, transpiration was measured at 1,000 μmol m-2 s-1 of photon flux density and leaf temperature was analyzed by thermal image. Net photosyntheis rate, stomatal conductance and transpiration rate in mixture traetment were 2 times of higher than in control. Water use efficience was not different significantly. Leaf temperature was lower in mixture treatment (25.3℃) than in control (29.0℃). Conclusion : This result show that foliar application of urea, ascorbic acid and calcium chloride was reducing a high temperature injury through a improving photosynthetical capacity and decreasing leaf temperature of Cnidium officinale.

Background : Management of air temperature are known to primarily affecting on physiological properties and yield in plant. Methods and Results : The effect of air temperature on characteristics of photosynthesis and chlorophyll fluorescence in Cnidium officinal were investigated using growth chamber after cultivating for 24 hours under controlled condition. Net photosyntheis rate, transpiration was measured at 1,000 μmol m-2 s-1 of photon flux density and chlorophyll fluorescence was analyzed by OJIP method. Net photosyntheis rate was highest in treatment of 25℃. Although transpiration rate was lowest, water use efficience was also in treatment of 25℃. Stomatal conductance was mainly influenced from ambient climatric factors such as vapor pressure deficit. As results of chlorophyll fluorescence by OJIP analysis, maximum quantum yield (Fv/Fm) of photosystem II (PSII), PIabs and the relative activities per reaction center such as ABS/RC, DIo/RC were not changed at air temperature. Therefore, elevated air temperatue during short term influence the dark reaction in photosystem through controlling a water use efficience and transpiration. Conclusion : This result show that 25℃ of air temperature may be a adequate temperature to improving the efficiency of photosynthesis in Cnidium officinale.

Background : Unlike Dioscorea japonica or Dioscore opposita, Dioscore alata is a high-temperature crop mainly cultivated in Africa and subtropical regions. Due to recent climate change, its cultivation area is expanding in Korea. In 2016, the Institute for Bioresource Research clarified optimal harvesting stage to increase its tuber yield and ensure safe storability. Methods and Results : As the seed-tubers for this study, Dioscorea alata tubers were cut into a size of 50 g, disinfected with lime powder, dentated on the seed bed with electrothermal wire installed on March 20th, and then planted on the main field on April 15th. The planting distance was 120 ㎝ in width, where the furrows of 90 ㎝ were cladded with black vinyl, in two rows with a column spacing of 25 ㎝. The amounts of applied fertilizers were 2,000 ㎏ compost, 34 ㎏ N2, 28 ㎏ P2O6, and 28 ㎏ K2O. The compost and P2O5 were used in full, where as N2 and K2O were used as original fertilizer 14 (10 ㎏) and additional fertilizer 20 (18 ㎏), respectively. The crop was harvested in six times from September 20th to November 9th, in an interval of 10 days. While harvesting, the ground fresh weight yield and underground tuber yield were investigated. The underground tuber yield was 836, 1,744 and 2,975 ㎏ low at the early harvests on September 20th, 30th, and October 10th, respectively, while it was 3,622, 3,828, 3,818 ㎏ high on October 20th, 30th, and November 9th, respectively. The ground fresh weight yield remained the same. To clarify tuber storability by harvest time, they were stored at 15℃after harvest, and then healthy and corrupt tubers were studied on March 23th. The corruption ratio by harvest time was highest at 39.1% and 29.3% on October 30th and November 9th, respectively, when frost and low temperature damaged harvest. It was 59.0% and 42.8% at the early harvests on September 20th and 30th, respectively. The corruption ratio was lowest on October 20th and October 10th at 29.3% and 39.1%, respectively. Conclusion : Ford. Dioscore alata cultivation, Korea presents a premature and disadvantageous environment with lower temperature and pre-harvest frost at the time of planting. After raising seeding on an electrically heated hot bed, the optimal harvesting stage should be from planting in the middle of April where temperature rises above 1 5℃ to harvesting in the period October 10th - 20th so as to achieve the maximum tuber yield and high storability.

Background : study of long yam and short yam (Dioscorea. opposita) are cultivated in temperate regions but tropical yam (Dioscorea alata) are mainly grown in Africa and sub-tropical regions cultivated crops. Recent tropical yam cultivation area of Korea increased but lack the proper cultivation techniques to climate warming. This study was conducted to elucidate the effect of the timely harvest on Tropical yam at 2015 in Institute of Bioresources Research, GBARES. Methods and Results : Tuber of tropical yam were cut as 40 g, and dust-coating sterilized with lime. Seedlings were grown in heating wire installed seed bed from 11. March to 16. May. Experimental field were fertilized 2,000 kg compost, 34 kg N2, 28 kg P2O5, and 28 kg K2O. All amount of compost and P2O5 treated as basal fertilizer. N2 and K2O treated 14 and 10 kg of basal fertilizer, and 20 and 18 kg of additional fertilizer, respectively. Tillage, covering black PE film with 60×25 cm spacing holes on 120 cm row were conducted. Emergence days from 6. April to 18 May until 28 days to 36 days but 15. June and 9. June were each 19 and 7 days. Dry weigh in early stage due to seedling date, while seedling date according from 6. April to 18. May had no difference. seedling date was not effective on total number of tuber but number of marketable tuber (over 200 g). Marketable tuber number of seedling date according to 20. April was increased 35~132% as 4,028 number per 10 a. And tuber with 20. April was 13~73 g heavier. Tuber yield and marketable tuber yield of seedling date as affected by 20. April were respectively 2,518 and 1,273 kg per 10 a compared to 6. April and from 4. May to 15. June as 1,743~2,457 kg and 484~1,027 kg. Conclusion : Tropical yam is low temperature in the cultivation of Korea but also adverse environmental conditions. Frost is not mature enough off before harvesting. Yam had significant increased marketable tuber (over 200 g) yield due to seedling in mid-April Requires cultivation technology.