Background: Some phenolics detected in the soil may inhibit the seed germination and seedling growth of ginseng (Panax ginseng). This study investigated the effect of irrigation and ginseng root residue addition on the soil microbial community and root rot disease in 2-year-old ginseng. Methods and Results: Each 20 ℓ pot was filled with soil infected with ginseng root rot pathogens, and irrigated daily with 2 ℓ of water for one month. After the irrigation treatment, ginseng fine root powder was mixed with the irrigated soil at a rate of 20 g per pot. In descending order, NO3 −, electric conductivity (EC), exchangeable Na (Ex. Na) and K (Ex. K) decreased due to irrigation. In descending order, NO3 −, EC, Ex. K, and available P2O5 increased with the additon of ginseng powder to the soil. The abundance of Trichoderma crassum decreased with irrigation, but increased again with the incorporation of ginseng powder. The abundance of Haematonectria haematococca increased with irrigation, but decreased with the incorporation of ginseng powder. The abundance of Cylindrocarpon spp. and Fusarium spp., which cause ginseng root rot, increased with the incorporation of ginseng powder. The abundance of Arthrobacter oryzae and Streptomyces lavendulae increased with irrigation. The abundance of Streptomyces lavendulae decreased, and that of Arthrobacter spp. increased, with the incorporation of ginseng powder. Aerial growth of ginseng was promoted by irrigation, and ginseng root rot increased with the incorporation of ginseng powder. Conclusions: Ginseng root residues in the soil affected soil nutrients and microorganisms, and promoted ginseng root rot, but did not affect the aerial growth of ginseng.

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.

Background: Some plants have harmful effects on fungi and bacteria as well as plants. Incorporating into soil as green manures are effective in reducing population densities of soil pathogens. Methods and Results: Twenty-three species of green manure crops were cultivated after the harvest of 6-year-old ginseng and then incorporated green manure into the soil at the flowering stage. The following year, the root rot ratio of 2-year-old ginseng and soil chemical properties were investigated. Sorghum sudanense, Helianthus annuus, and Helianthus tuberosus were relatively high in dry matter production. Without incorporating green manure into soil, NO3, EC (electric conductivity) and K were decreased by 95%, 79% and 65%, respectively. When green manure was incorporated to soil, P2O5 and NO3, were reduced by 41% and 25%, respectively. The survived root ratio of 2-year-old ginseng were significantly increased by 56.2%, 47.5%, and 47.3% in Sorghum sudanense, Ricinus communis and Helianthus tuberosus, respectively, In addition, there was a significant increase in Secale cereale, Chrysanthemum morifolium, Atractylodes macrocephala, and Smallanthus sonchifolius. The survived root ratio of ginseng showed a significant positive correlation with soil pH and a negative correlation with NO3, and EC. Conclusion: Cultivation of Chrysanthemum family mainly using rhizome and root as green manure was effective for root rot disease of ginseng.

Background: Some plants have harmful effects on fungi and bacteria as well as other plants. Incorporating such plant into soil as green manure is effective in reducing population densities of soil pathogens. Methods and Results: Twenty-three species of green manure crops were cultivated after the harvest of 6-year-old ginseng and then incorporated into the soil at the flowering stage. The following year, the root rot ratio of 2-year-old ginseng and soil chemical properties were investigated. In the absence of green manure addition, the NO3 content, electric conductivity (EC), and K content decreased by 95%, 79% and 65%, respectively. In the presence of green manure addition, P2O5 and NO3 contents reduced by 41% and 25%, respectively. The “survived root ratio” of 2-year-old ginseng significantly increased by 56.2%, 47.5%, and 47.3%, in the Sorghum sudanense, Ricinus communis and Helianthus tuberosus treatment, respectively. In addition, there was a significant increase in the “survived root ratio” in the Secale cereale, Chrysanthemum morifolium, Atractylodes macrocephala, and Smallanthus sonchifolius treatments. The “survived root ratio” of ginseng showed a significant positive correlation with the soil pH and a negative correlation with the NO3 contents, and EC. Conclusions: Cultivation of plant form the Chrysanthemum family as green manure, using mainly the rhizomes was effective for the control of root rot disease of ginseng.

Background : Ginseng is a perennial, and damage occurs due to various diseases and pests. As a result, yield decreases and quality deteriorates. In particular, it is impossible to be repeatedly cultivated due to root rot, soil-borne disease. For this, in order to control root rot and repeatedly cultivate ginseng by using soil fumigation from virgin soil, this experiment was conducted. Methods and Results : This experiment was performed in ginseng farm field, Geumsan-gun, Chungnam province. And total area was 3ha. And the experiment was conducted in soil where apple trees had been grown. Apple trees were rooted up in 2006. And soil was fumigated in May 2007. With regard to soil fumigant, soil was treated with Basamid of 40kg/10a. After soil fumigation, 5 ton/10a of cattle manure fermented for 1 year was put in the soil in June, and then the soil was cared for by being plowed and rotary-tilled as occasion. Ginseng seeds were sowed in the soil cared for in October 2007. And 4-year-old ginseng was harvested in 2011. The soil from which ginseng was harvested was fumigated by the same method in May 2012, and then ginseng seeds were sowed in 1.5ha in October 2012 and in 1.5ha in October 2013. In October 2013, 3-year-old and 4-year-old ginseng was harvested. And ginseng growth characteristics and root rot incidence was examined. It was shown that 4-year-old ginseng yield after the fumigation of virgin soil was nearly 2 times as high as that of conventional virgin soil cultivation. And root rot didn't occur. After that time, the soil was fumigated again. And when ginseng was cultivated, 3-year-old and 4-year-old ginseng yield was 650kg and 960kg per 10a. And it was shown that root rot incidence was 1.3% and 15.3% in 3-year-old and 4-year-old ginseng respectively. Conclusion : This study showed the results where ginseng can be cultivated repeatedly if soil was fumigated again after ginseng was harvested following the soil fumigation from virgin soil so as to control the ginseng root rot and cultivate ginseng repeatedly.

Background : The area of ginseng cultivation has nearly exhausted in the main ginseng growing area in Korea but virgin fields need for ginseng cultivation due to continuous cropping injury. To count for the decrease of the virgin fields of ginseng cultivation, technical improvement to increase, or maintain the amount of harvest are necessary in ginseng cultivation. The Ginseng Rain-sheltered Shade House is one of the efficient cultivation techniques as reducing the damages caused by natural disaster such as blight, high temperature & humidity, dry, and heavy rain & snow. However a soil description needs to be developed to reduce the period of re-cultivation because ginseng has to be cultivated at the only one ginseng rain-sheltered house without soil or cultivation change. Methods and Results : This study was carried out in the ginseng rain-sheltered house where ginseng had cultivated and harvested one time. Each section of Cultivation of sudan grass+flooding, rice straw+flooding, and flooding was covered with vinyl and then, all areas were solarized through the summer season. The soil temperature was inspected at 5cm, 10cm, 15cm, and 20cm below ground. As a result, the soil temperature of the place with vinyl covered and solarized was approached to 40℃ regularly during the period of high temperature in July and August. After the solarization, the inspection result of Cylindrocarpon destructans spore density checked by Real time PCR was that C. destructans spores were not found at the place where sudan glass+flooding and rice straw+flooding were used. However, the detected number of C. destructans spores in the inspection condition was roughly 9 at the soil samples from the fields which were flooded and solarized, and 33 at those from the repeatedly cultivated fields. The evaluations of aerial part growth by measurements were good in the following order: Sudan grass+flooding, rice straw+flooding, and flooding. Conclusion : The purpose of this study was to reduce the period of ginseng re-cultivation in a ginseng rain-sheltered shade house. The incidence rate of the pathogens distantly decreased by the treatments of sudan glass + flooding, rice straw+flooding, and solarization.

본 연구는 시설하우스 내 토마토 연작장해 경감을 위해 단기 녹비작물 재배가 토마토의 생육특성 및 수량에 미치는 영향을 알아보기 위해 토마토 시설재배지에 헤어리베치와 호밀을 단파 및 혼파로 구분하여 파종하였으며, 생육된 녹비작물의 양분공 급량과 녹비작물의 토양환원 후 토양의 이화학적 특성 그리고 녹비작물 환원 후 후작물인 토마토의 생육특성 및 토마토 시들 음 병원균의 밀도를 조사한 결과, 녹비작물의 질소(N), 인(P2O5), 칼륨(K2O), 칼슘(CaO) 및 마그네슘(MgO) 공급량은 헤어리베 치의 경우 각각 26.2, 5.8, 10.2, 6.6, 및 1.5 ㎏/10a였으며, 호밀 은 각각 9.1, 4.2, 11.8, 3.8, 및 3.1 ㎏/10a였고, 혼파의 경우는 단파와 유사한 경향이었다. 토마토 시설재배지에서 녹비작물 의 토양환원 전･후 토양의 pH는 대조구와 별다른 차이 없이 6.37-6.52 범위였으며, EC는 헤어리베치(2.64 dS/m) 및 호밀 (2.62 dS/m) 처리가 대조구(헤어리베치-2.80 dS/m, 호밀 -2.91 dS/m)에 비해 낮았다. 토양 중 유기물, T-N 및 avail. P2O5 함량은 녹비작물 처리가 대조구에 비해 증가하는 경향이 었다. 녹비작물 토양환원에 따른 후작물인 토마토 생육은 녹비 작물 처리는 대조구에 비해 우수한 생육을 보였으나, 관행처리 와는 비슷한 생육을 보였다. 또한 녹비처리에서 토마토 시들음 병원균의 밀도가 현저하게 감소하였다. 이상의 결과를 종합할 때, 토마토 시설재배지에서 녹비작물의 시용은 비료로서 충분 한 가치가 있으며, 녹비작물 토양 환원 후 토양화학성을 개선함 으로써 시설하우스 토마토 연작재배지의 연작장해를 경감할 수 있을 것으로 사료된다.

Storage root yield of sweetpotato was decreasing owing to continuous sweetpotato cropping, debasement of soil physical properties, increasing incidence of pest and disease. This study was conducted to evaluate the changes in physicochemical properties of the soil owing to subsoiling (subsoiling to 50 cm depth), and the effect on growth and yield of sweetpotato. The subsoiling treatments included subsoiling treated every year for two years, subsoiling in the first year, and no subsoiling control. The soil physical properties measured were bulk density, hardness, porosity, three phase. Bulk density, porosity, soild (%) of three phase were improved by subsoiling in topsoil and subsoil. Main vine length and vine yield in subsoiling soil were higher than those in no subsoiling soil, but those were not significantly different. Yield of marketable storage root in subsoiling soils treated every year for two years and treated in the first year was more increased 17% and 20% than no subsoiling soil, respectively. The number of marketable storage root per plant was also higher in subsoiling soils than no subsoiling soil, but it was not significantly different. Soluble solid contents and total free sugar contents of storage root of sweetpotato were not significantly different among the treatments. These results show that improving soil physical properties by subsoiling could promote high yield of marketable storage root in continuous sweetpotato cropping field.

화산회토양 감자 연작지 토양 pH 수준별로 고토석회, 유황, 황산칼륨, 패화석, 규산질비료, 석회질소, 유안비료를 이용하여 감자 더뎅이병 발생을 경감시키고 토양건전성을 유지하는데 적절한 대체농자재를 선발하고자 수행하였다. 토양 pH가 낮은 황산칼륨 처리구(24 kg/10a)에서는 더뎅이병 발병률이 84.4%, 발병도가 28.4%로 가장 낮았다. 방제효과는 12.3%, 상품율은 93.2%로 다른 처리구와 비교할 때 가장 높게 나타났다. 석회질소 처리구(60 kg/10a)가 발병도 38.3%로 낮았고 방제효과 23.8%, 상품율 66.3%로 높았다. 토양 pH가 높은 시험구 중 더뎅이병 발병률은 석회질소 처리구(60 kg/10a)가 38.3%로 가장 낮았고 유안 처리구(48 kg/10a)는 62.6%로 높았다. 더뎅이병 방제효과는 석회질소 처리구(60 kg/10a)에서 23.8%로 유황 처리구의 6.1% 보다 4배 이상, 상품률은 66.3%로 가장 높게 나타났다. 감자 더뎅이병 병원균 Streptomyces acidiscabies과 Streptomyces scabiei를 석회질소 2.5, 5 g/L, 10 g/L에 접종시 생장량은 다른 토양개량제 보다 상대적으로 억제되었다. 결론적으로 감자 파종 전에 토양 pH가 5 이하이면 황산칼륨을, 6 이상이면 석회질소를 시비하면 더뎅이병 발생을 경감시킬 수 있을 것으로 보인다.

고구마의 연작장해를 경감시키기 위하여, 연작지 토양과 심토반전 토양에서 농가묘와 바이러스 무병묘를 70×25cm 간격으로 재배하였다. 연작지 토양의 시비량은 N-P2O5-K2O = 55-63-156kgha1과 우분퇴비 10tonha1으로 표준시비를 하였고, 심토반전 토양은 질소비료와 퇴비만을 50% 증시하였다. 삽식 30, 120일째의 생육과 수량 및 품질특성을 조사한 결과는 다음과 같다. 1. 삽식 30일경부터 농가묘에서는 바이러스 병징이 뚜렷하였으나, 무병묘에서는 나타나지 않았다. 2. 무병묘의 수량성은 농가묘보다 심토반전 토양 15.0%, 연작지 10.5%의 증가를 보였다. 3. 심토반전 토양에서의 수량성은 연작지보다 농가묘 8.8%, 무병묘 3.2%의 증가를 보였으며, 심토반전 토양에서 바이러스 무병묘 재배는 상저비율이 농가묘(60.1%) 대비 80%로 높아져 경제성이 있었다. 4. 무병묘에서 수확한 고구마의 품질은 농가묘보다 피색이 선명하고, 고구마 모양이 좋아져 외관 품질향상에도 유리하였다. 5. 심토반전 토양 및 무병묘에서 수량증가는 30일째 엽수와 120일째 분지수와 정의 상관관계(p=0.05)가 인정되었으며, 이는 고구마 괴근형성에 초기생육이 중요하다는 것을 보여주었다.

To improve the soil properties of physical and microbial community rice bran and wood charcoal were applied in the continuously cultivated plastic 꺼1m house soil. Soil physical properties were improved by application of rice bran and charcoal compared to chemical fertilizer application (control) by 8-14% in bulk density and 5-9% in soil porosity. Changes in the biological ratio indexes of fatty acids in the soils were detected depending on the inputted materials. Especially in application of rice bran including mixture with charcoal, much more fungi and less bacteria were detected and the ratio of fungi to bacteria was increased, suggesting the more organic carbon metabolically active in these treatments. The high ratio of aerobe to anaerobe suggested the better aerobic conditions were in the soil inputted wood charcoal. From these results, it is important and possible to select some materials for the organic pepper cultivation, which may improve the poor condition soil.

Green manure crops play an inportant role in organic farming. Field experiment was conducted at paddy soi1 (fine loamy, mixed, nonacid, mesic family of Aeric Fluvaquentíc Endoquepts) ín 2008/2009 to 2009/2010 at the Natíonallnstítute of Crop Science (NICS), RDA, Suwon, Gyeonggí provínce, Korea. This expe꺼ment was carried out to evaluate the biomass of haíry vetch (Vicia víllosa) and growth of rice (Oryza satíva) by cjífferent seedíng rates. Seeding rates of hairy vetch consisted of 30, 60, and 90 kg ha-' by broadcasting before rice harvesting. The biomass af)d nitrogen production of hairy vetch were not significantly different between 60 kg ha-’ and 90 kg ha-’ of seeding rates. Also, rice yield was not siginicantly differnt between seeding rate 60 kg ha-’ of hairy vetch and conventional pratice for two years. Therefore, we suggested that seeding rate of hairy vetch should be reduced by continuous cropping and incoportion of hairy vetch under rice-based cropping system.

인삼 연작장해 원인과 경감대책을 수립하고자 2004년에는 2005년까지 작물과학원 증평시험지 연작토양에서 인삼 수확경 과년수와 예정지관리 유무에 따른 시험을 수행한 결과를 요약하면 다음과 같다. 인삼 연작지 수확경과년수가 짧을수록 생존율이 낮아지며 3~4년 경과구 81~95%의 뿌리썩음 이병주율을 보였다. 예정지 관리구는 미관리구보다 생존율이 다소 높으며 뿌리 썩음병 피해도 예정지 미관리와 같은 경향으로 예정지 관리효과는 크지 않다. 수확경과년수가 10년이상의 연작지에서도 연작장해를 일으키는 병원균 (C. destructans)이 분리되므로 재작 또는 연작시는 이점을 고려하여 재배지를 재선정하거나 예정지 토양관리대책을 수립해야 할 것으로 판단된다.