전 세계적인 지구 온난화로 인한 가뭄은 농작물의 생산성을 저해하는 주요 원인 중 하나이며, 고온과 건조가 복합적으로 작용하여 식물 생장을 감소시킨다. 본 연구에서는 Bacillus velezensis YP2 균주의 식물 생육촉진 및 건조 스트레스 내성 증진 효과를 온실과 시설하우스 포장에서 조사하였다. 또한 B. velezensis YP2 균주의 처리 전과 후 케일 근권과 뿌리에서 배양법에 의한 상대 정량 방법으로 B. velezensis YP2 균주의 근권 및 뿌리 정착능을 분석하였다. 온실 검정 결과 YP2 균주 처리구에서는 무처리구와 비교하여 케일 유묘의 초장 26.7% 및 지상부 생체중 142.2% 증가시키는 효과가 있었다. 또한 B. velezensis YP2 처리구에서는 무처리구와 비교하여 39.4%의 건조 피해 경감 효과가 있었다. 시설하우스 포장 검정 결과에서도 B. velezensis YP2 균주 처리에 의한 케일의 생장촉진 효과와 건조 스트레스 내성 증진 효과가 있었으며, B. velezensis YP2 처리구에서 케일 잎의 상대수분함량이 무처리구와 비교하여 7, 10, 14일에 모두 높은 것으로 나타났다. B. velezensis YP2 균주의 뿌리 정착능 분석 결과, 균주 처리 21일까지 케일 근권 및 뿌리 균밀도가 무처리구와 비교하여 B. velezensis YP2 처리구에서 유의하게 높은 것으로 나타났다. 따라서 균주 처리 후 최소한 21일이 경과할 때까지 B. velezensis YP2 균주가 케일 근권과 뿌리에 정착하여 식물과 상호작용함으로서 생육을 촉진하고 식물의 물 이용률을 증가시켜 건조 스트레스 내성을 증진하는 데 관련이 있을 것으로 판단된다. 본 연구 결과를 통하여 B. velezensis YP2 균주는 가뭄으로 인한 건조한 토양 조건에서 작물 생산성을 향상시키는 가능성이 있는 유용한 미생물로 이용할 수 있을 것으로 생각된다.

Background: This study were performed to determine the effect of root pruning of Zizyphus jujuba var. inermis (Bunge) Rehder. Root cutting inhibit vegetative growth and promote reproductive growth as temporarily reducing growth, net assimilation, water potential of leaf and cytokinin level. Methods and Results: The root pruning was treated of the root cutting widths 50, and 80㎝ and the root cutting depths 10, and 20㎝. The amount of root pruning and the number of suckers were the highest in the root-pruning treatment at a width of 50㎝ and a depth of 20㎝. The blooming time was from June 18 to 20, and no difference was observed in the blooming time among the rootpruning treatments. The number of flowers was rather higher in the root-pruning treatment at a width of 50㎝ and a depth of 20㎝ and at a width of 80㎝ and a depth of 20㎝. The percentage of fruit setting was higher in the plants whose roots were pruned at a depth of 20㎝ than in the untreated plants. The fruit size, fruit weight, and sugar content showed no difference among the root-pruning treatments. Conclusions: The results showed that percentage of fruit setting increased with root pruning, while no difference was observed in the growth and fruit quality of plants.

Background : The study is designed to select the organic fertilizer as an additional fertilizer suitable for improving the yield of ginseng cultivar K-1 at low productive land when it is cultivated as 6-year old red ginseng. Methods and Results : This study was conducted in 2016 at a farm in Paju cultivating 6-year old ginseng root. As for the management of the cultivation land, in 2010 and 2011, Sudangrass was cultivated in order to make the organic matter content and chemical composition suitable for ginseng cultivation, and more than 15 tillage works were carried out a year. The transplantation was carried out at the planting density of 63 weeks / 1.62 ㎡ in April 2012. On May 2, the amount of 15 ℓ / 1.62 ㎡ of N 1.5 ㎏/1,000 ㎡ was supplied to the non-treatment, liquid fertilizer of fermented rice bran, liquid fertilizer of fermented soybean, seaweed and liquid yeast. N 1.5 ㎏/1,000 ㎡ was put into the soil for the fermented soybean and leaf mold. The photosynthetic rate was measured on the middle part of the small leaf by using a photosynthetic analyzer (LI-6400, Li-COR) at 10 : 00 - 14 : 00 on a clear day under PAR (photosynthetically active radiation) of 100, 200, 400, 600, 800, 1,000, 1,400, 1,800 μmol s-1m-2. The growth features of ginseng (including the length of stem, length of leaf, width of leaf, length of root and yield, etc.) as well as leaf discoloration, and root rot, etc were examined. The statistical analysis was performed 3 times in the randomized block design. For the rate of photosynthesis, the liquid fertilizer of fermented rice bran > liquid fertilizer of fermented soybean ≒ untreated ≒ fermented soybean > seaweed > liquid yeast > leaf mold was higher in that order. The survival rate ranged from 42.9% to 51.9%. As for the above-ground growth characteristics, the liquid fertilizer of fermented rice bran, liquid fertilizer of fermented soybean, seaweed and liquid yeast showed higher performance than the non-treated while the fermented soybean and leaf mold showed similar performance to the non-treatment. As for the underground growth, the liquid fertilizer of fermented rice-bran, liquid fertilizer of fermented soybean, fermented soybean, or leaf mold showed the same performance as non-treatment while the fermented soybean or leaf mold showed shorter length than non-treatment. As for the yield, the liquid fertilizer of fermented rice-bran, or liquid fertilizer of fermented soybean showed better performance than non-treatment. Conclusion : In conclusion, it was found that liquid fertilizer of fermented rice bran and liquid fertilizer of fermented soybean are the suitable organic fertilizers which can be used in ginseng cultivation for improving the quantitative yield of 6-year-old ginseng in low-producing area.

This study was conducted to elucidate the effects of mulching materials on root growth characteristics and weed occurrence of Platycodon grandiflorum transplants (3 years old) in organic farming. After transplanting, roots were mulched with one of three mulching materials (biodegradable film, sawdust, or rice husks) or a control (no mulching). The average root diameter of all mulching groups was 28.1 mm, which was 5.1 mm thicker than the no-mulching treatment. Roots with the biodegradable film treatment were the thickest at 30.9 mm. Root length was the shortest, 22.0 cm, with rice husk mulching. The number of rootlets was the highest with film mulching (36.0 rootlets/root) and the lowest with no mulching. For root fresh weight, which directly affects yield, the average of treated and untreated roots was 100 and 56 g/root, respectively. The highest fresh weight was in the biodegradable film plot (130 g/root). The mulching treatment groups showed a weed inhibition effect compared with the no-mulching treatment. The dominant weeds with the no-mulching treatment were Setaria viridis and Digitaria ciliaris, and that with the mulching treatment was Setaria viridis. Average annual weed occurrence across all treatments was 72%. Weed occurrence was the highest with the no-mulching treatment (125 weeds/m 2 ), and there were no weeds with the biodegradable film treatment.

Background : Ginseng root rot caused by soil-borne pathogens, Cylindrocarpon destructans and Fusarium solani, is a major factors of replanting failure in ginseng cultivation. Some of the phenolic compounds detected in the soil of commercially cultivated American ginseng could inhibit the seed germination and seedling growth of American ginseng. Our study is to investigate the causes of replanting failure of ginseng by overhead flooding treatment and soil incorporation of ginseng fine root in soil infected with root rot pathogens. Methods and Results : To make soil occurring continuous cropping injury, 2-year-old ginseng infected with Cylindrocarpon destructans replanted in soil cultivated ginseng for 5 years. Treatment are as follows: 1) control, 2) water of 2ℓ was irrigate infected soil of 20ℓ, 3) ginseng fine root of 20g was mixed with infected soil of 20ℓ. Soil pH was increased, while other inorganic components were significantly reduced by overhead flooding treatment. Soil incorporation of ginseng fine root decreased soil pH, but increased EC, NO3, P2O5 and K, meanwhile, did not affected changes in organic matter, calcium, magnesium, sodium. Irrigation treatment in soil occurring replanted failure promoted distinctly above-ground growth of ginseng, and inhibited the occurrence of root rot because inorganic nutrient like NO3, P2O5 and K were decreased to optimal levels, and the density of soil pathogens could be reduced. Growth of ginseng was not inhibited, while root rot was promoted by soil incorporation of ginseng fine root. Conclusion : Irrigation treatment was effective in promoting the growth of ginseng and inhibited root rot distinctly. Ginseng fine root remaining in the soil after ginseng harvest did not affect the above-ground growth of ginseng, while promoted the occurrence of root rot.

Background : Panax ginseng C.A.Meyer is a perennial herb and its growth potential keep relatively high at least for the early 3 years old. If the transplanted ginseng roots of 2 or 3 years old grow well, a period of cultivation and the disease management cost could be reduced for the production of 6 years old ginseng roots. Methods and Results : The rooting and growth of a transplanted ginseng root could be affected by the age of a transplant. Therefore, the experiments were conducted to examine the influences of the age factor on the rooting and growth of transplanted ginseng roots. The ginseng roots with different plant ages in growth years (1, 2, and 3 years old), used in this study, were obtained by raising in a seedling production field near the Punggi Ginseng Experiment Station. The transplants were continuously grown under the same conditions after transplanting. The number of lateral or branched roots at the root-growing period after transplanting was basically higher in originally older plant ages compared to younger plants: the numbers of secondary and tertiary branched roots of the 1 year-old transplants were 8, 12, respectably; 2 years old: 12, 20; 3 years old: 12, 28. Those did not show any difference in both overground and underground growing, in compared to conventional cultivations with roots of a year old. The plants grew well without anthracnose, spotting disease, and high temperature injury. Conclusion : The conventional cultivation period of above 5 or 6 years for the raw material of red ginseng might be shorten and also the cost of disease control could be decreased, by transplanting of 2 or 3 years old roots raised at a seedling nursing field.

The present study aimed to determine the influence of various root restriction media on seedling quality and early growth of strawberry after transplanting. The root activity of the seedlings, measured 20 days after fixation, was considerably higher (0.096, 0.090, and 0.063 mg·g-1·h-1 at 420, 450, and 480 nm, respectively) in expanded rice hull (ERH) treatment than in the sandy loam and loamy sand treatments. The volumetric water content (VWC) of the root media tested across 3 irrigation regimes (15 d, 30 d, 45 d) in the nursery field was highest in sandy loam (65.0–66.8%), followed by 59.4–61.3% in loamy sand and 38.6–45.3% in ERH. When growth parameters of runner plantlets were compared, ERH treatment was found to result in the highest crown thickness and fresh weights of root and above-ground parts. This had a favorable influence on above-ground tissue growth after transplanting to plastic house soil. As mentioned above, ERH treatment resulted in the highest seedling quality and early growth after transplanting. The results of this study would serve as useful on-site data for the production of high-quality strawberry seedlings.

Nitrogen in rice paddy soils and utilized as the major source for N-assimilation in rice crops. In roots, transcriptional activities of ammonium uptake and assimilation genes are highly sensitive to the availability of exogenous ammonium. However, little is known about the transcription factor genes that regulated by ammonium supply and its role to roots and plant developments. To study the transcription factor genes that involved in Ammonium response, two weeks old rice seedlings treated using Ammonium from 0 to 3 hours. Total RNA collected from each sample and samples were prepared for Agilent 8x60K microarray system. Based on the microarray data, we select transcription factor genes that highly affected by ammonium and selected knock out mutant candidates that used for phenotype screening.

To control the disease of root rot in ginseng nursery, inorganic sulfur solution of 0.1%, 1.0%, and 2.0% were irrigated by amount of 10ℓ per 3.3m2 before sowing. On the last ten days of July, Fusarium solani and F. oxysporum were similarly detected by 44.8% and 43.8%, respectively, while Cylindrocarpon destructans was low detected by 4.4% in the diseased seedling. The more sulfur's concentration was increased, the more soil pH was decreased. Soil pH was decreased from 5.87 to 4.59 by the irrigation of sulfur solution of 1.0%. The more sulfur's concentration was increased, the more electrical conductivity (EC) of soil was increased. EC was increased from 0.27 dS/m to 1.28 dS/m by the irrigation of sulfur solution of 1.0%. Irrigation of sulfur solution was effective on the inhibition of damping-off caused by Rhizoctonia solani in ginseng seedling. Control value for damping-off by the irrigation of sulfur solution of 1.0% and 2.0% were 75.7%, and 78.5%, respectively. Growth of leaf was inhibited by the irrigation of sulfur solution of 2.0%. Root weight per 3.3m2 showed the peak in sulfur solution of 1.0%, while survived-root ratio and root weight per plant were decreased in the level of 2.0%. Survived-root ratio of seedling in sulfur solution of 1.0% was distinctly increased by 4.7 times compare to the control, but control value for root rot was relatively low as 49.2%. Mycelium growth of C. destructans, F. solani, and R. solani were distinctly inhibited by the increase of sulfur's concentration in vitro culture using PDA medium.

This study was carried out in order to investigate the early growth and root development characteristics of Peucedanum japonicum container seedlings. The experiment was performed by containers (128 and 200 cavities containers) and shading levels (0%, 35%, 50% and 75% shading). Germination rate of P. japonicum seeds was getting higher in the lower shading level and the highest in the full sunlight (71.9%). Plant height was the highest under 50% shading of all containers. Fresh weight and dry weight of the shoot (leaves + stem) were the highest under 50% shading of all containers, too. Meanwhile, fresh weight and dry weight of the root per plant were the highest under the full sunlight of 128 cavities container such as 0.34 g and 0.03 g, respectively. Total root length, root project area and root surface area were higher under the full sunlight of 128 cavities container such as 234.5 cm, 6.6cm2 and 20.8cm2, respectively and the next higher was under 35% shading such as 201.7 cm, 5.9cm2 and 18.4cm2, respectively. A case of root volume was the highest with 0.15cm3 under the full sunlight. As a result of the surveying the whole experiment, it is concluded that the shoot and root of P. japonicum seedling grow nicely by maintaining 35% shading.

A root serves as an essential organ in plant growth by up-taking nutrients and water from soil and supporting the rest of a plant body. Root apical growth and system architecture have been extensively studied because they strongly affect overall plant growth and yields. Some plant species also utilize roots as storage organs. Many of them, including sweet potatoes (Ipomoea batatas), cassava (Manihot esculenta), and radish (Raphanus sativus) are important crops, however their root development has remained elusive. In this study, we characterized radial root growth in the radish and found that it is very similar to the secondary growth in stems. We identified well established cambium zones in the actively growing radish roots. Cell proliferation activities in the cambium zones positively correlated with root growth rates and final yields. Through a comparative analysis with Arabidopsis root expression data, we selected some putative transcription factors whose expression is highly enriched in the cambia and validated their expression in various stages of radish roots. By comparing their expression in two inbred lines with distinctive radial root growth, we identified transcription factors that are involved in morphological differences. More importantly, our investigation suggests that the differences in the root growth of two radish inbred lines are from changes in cytokinin responses. These findings together highlight that radish could serve as an excellent system for studying root crops and that transcriptional regulation and cytokinin signaling are indispensable for the secondary root growth.

고구마 괴근의 표피에 선모양으로 돌출되어 나타나는 피맥의 발생동향을 조사하고, 경감하기 위한 시험의 결과는 아래와 같다. 1. 고구마 피맥은 표피가 줄무늬로 돌출되어 상품성을 저하시키는 증상으로서 피맥발생은 표피층에 전분이 집적되어 발생하는 것으로 관찰되었고, 조기재배보다 보통기재배에서 발생이 많았다. 2. 고구마 품종에 따른 피맥발생은 건풍미, 연황미, 건미 등 7품종이 3%이하로 적었고, 헬씨미, 보라미는 30%이상 발생하였다. 만중은 피맥발생과 정의 상관관계가 있었다. 3. 고구마 피맥은 생육기간이 진전됨에 따라 증가하다가 삽식 후 120일경에 가장 높았다. 4. 고구마 삽식 후 90일의 적심비율에 따른 피맥발생율은 일정한 경향을 보이지는 않았다. 엽면적지수 4에서 피맥발생율이 가장 적었으나, 일정한 경향을 보이지는 않았고, 경엽절제비율이 높을수록 수량감소가 크게 나타났다.

This study was carried out in order to investigate the early growth and root development characteristics ofAtractylodes japonica container seedling. Experiment was performed by light intensity (100%, 60%, 25% and 10% of fullsunlight). Height was surveyed well under 25% of full sunlight (overall 11.013.0%). Root collar diameter was the highest inthe full sunlight (7.52㎜). It was the highest fresh weight (1.52g, 0.92g, 0.90g and 3.34g) under 25% of full sunlight, rootdry weight was getting higher in the higher light level and the highest in the full sunlight (0.13g). Total root length, rootproject area, root surface area and root volume were the highest under 25% of full sunlight (434.7㎝, 17.4㎠, 54.7㎠,0.55㎤, respectively) and the lowest under 10% of full sunlight. As a result of surveying the whole experiment, A. japonica isjudged nicely by maintaining 25% of full sunlight, excepting 10% of full sunlight. And light levels during the early growthare overly important to improve early growth.

목초액을 친환경 인삼재배에 이용하기 위하여 전엽기 이후인 6월 중순부터 지상부에 엽면시비로 살포하여 3년생 인삼 잎의 형태적특성과 수량에 미치는 영향을 조사하였다. 목초액을 처리하면 처리농도에 관계없이 해면조직의 배열이 3층에서 4층으로 증가하였다. 또한 인삼 잎의 상표피와 하표피의 두께가 두꺼워지고, 엽육세포도 두꺼워지는 효과를 보였으며 지하부의 생육에도 영향을 미쳐 무처리에 비해 뿌리의 생육이 증진되었으며 인삼 뿌리의 수량도 증가하였다. 따라서 목초액의 혼합사용은 인삼의 생육을 촉진시키고, 병해를 극복하여 인삼을 친환경재배 할 수 있는 대안이 될 것이다.

This study was carried out to have the basic and applied information to develop the cultivation methods and models and to increase the productivity of high-quality ginseng. Plant height was dramatically increased from one year old to four years old, and then it was grown up very slowly. Stem length was shown similar tendency as the plant height did. Its range were from 9.4 cm in one year old to about 42.4 cm in four year-old ginseng. The leaf area was clearly increased until four years old, 10.1cm2 in one year old to 204.9cm2 in four years old, while it was slightly increased after four years old. Root length was continuously increased from one year old until four years old, and then it was grown up very slowly. Tap root length which was measured was appeared about 8 cm from three years old to six years old, showing not much different among the year-olds. The root diameter was continuously increased from one year old to six year-old ginseng, about 2.9 mm and about 19 mm, respectively. The moisture content was higher on the shoot than that on the root. It was slightly decreased as they were getting old. In shoot part, the rate of leaves and stems based on dry weight was about 1 : 1. In the root, the dry weight of tap root was heavier than that of lateral root. The dry weight of shoot was decreased after four years old, while it of the root was continuously increased until six years old, resulting the production of ginseng root. Based on the results of this study, growth characteristics of shoot and root of ginseng were dramatically increased from one year old to four years old and then their growths were appeared different between shoot and root, showing not much growing in shoot and keep growing in root.