• Korean Journal of Organic Agriculture
• /
• v.25 no.3
• /
• pp.603-617
• /
• 2017

The occurrence and management of disease and pests in six organic peach orchards were surveyed from March 2015 to March 2017. In this period, the number of certified organic and non-chemical peach farms increased to 65.5% and 31.7%, respectively. Certified organic peach farms were selected based on more than $4,000m^2$ of cultivation area and three tons of production, and their cultivation status was examined. All of the farms were either cultivated green manure crop or sod, and limited vegetation control to a minimum. For the management of soil nutrients, many farmers used livestock manure, oilcake and self-manufacturing liquid fertilizer. It was surveyed that bordeaux mixture, lime sulfur, pheromone for mating disruption of moths and plant extract were used for disease and pest control. The damage caused by the pests and diseases were 31.6% and 24.1%, respectively. The oriental fruit moth showed the highest damage rate (13.5%) in the organic peach orchards, followed by the brown rot (13.0%), peach fruit moth (7.3%) and bacterial shot hole (7.3%).

• Korean Journal of Organic Agriculture
• /
• v.17 no.2
• /
• pp.253-264
• /
• 2009

This study was conducted to establish agricultural practices to control diseases and insects for chemical pesticide-free cultivation of leafy vegetables. Two diseases, gray mold(Botrytis cinerea) and soft rot(Erwinia carotovora), on lettuce were reduced by controlling temperature and humidity using air-circulation fan. The aphidophagous lady beetle(Harmonia axyridis) and primary parasitoids(Aphidius colemani) showed activity to control aphids density on Chinese cabbage. Co-application of cooking oil and yolk mixture (COY) and BT(Bacillus thuringiensis) decreased diseases including soft rot(Erwinia carotovora), downy mildew(Peronospora brassicae Gaumann), and powdery mildew(Eryslphe polygoni), and insects such as diamondback moth(Plutella xylostella) and beet armyworm(Spodoptera exigua Hubner). Neem extract treatment reduced downy mildew(Peronospora destructor) on Welsh onion.

• Journal of Advanced Marine Engineering and Technology
• /
• v.12 no.3
• /
• pp.57-67
• /
• 1988

Although handicapped by the inability to bridge the size gap between small laboratory sample and large engineering component, the V charpy test sample method does possess certain advantages, such as each of preparation, simplicity of test method, speed, low cost in test machinery, and low cost per test. On the other hand, the COD test method does posses advantages, which reduce the size gap between the laboratory sample and actual engineering component. Consequently, the correlation between V charpy absorbed energy and the critical COD value is required for estimating critical COD value from the simple V charpy test results. In this paper, the high tensile strength steel AH36 plate specimens having a single edge cracked notch were investigated to find out the correlation between V charpy absorbed energy and critical COD value in the welded parts under such various welding methods as shielded metal arc welding, the submerged arc welding and the electro gas welding by means of V charpy impact test and static 3-point bending test. Main results obtained are as follow ; 1. The relationships between V charpy absorbed energy Wc' and critical COD value ($\delta_c$)show; $\delta_c$=0.0065 Wc'+0.1906. 2. Ductile- brittle transition behaviours can be estimated by means of fracture appearance and general yielding behaviours. 3. The V charpy absorbed energy of SMAW is higher than that of SAW, EGW and similar relationships are obtained in the COD tests.

• Conservation Science in Museum
• /
• v.12
• /
• pp.77-88
• /
• 2011

The study investigated conservation and fiber of 66 letters of Sukmyeonghancheob (national treasure No.1629) that the National Cheongju Museum kept. Before treatment, the cover was destroyed and inner paper was stained by water and humidity and destroyed by insects. One volume of King Hyojong was kept at separate frame. The author disassembled book and removed old Baejeobji and inspected paper quality of letter and tested fiber by using C-stain: The author reassembled one volume by including one letter separated after repairing destroyed area of the edge.

• 보존과학연구
• /
• s.35
• /
• pp.121-127
• /
• 2014

The Vietnam homecoming box that has been collected in National Museum of Korean The Vietnam homecoming box that has been collected in National Museum of Korean Contemporary History got severely damaged such as rot, attached foreign substance, fading, color, wood decay. In particular, the bottom of the box was unstable state that deteriorated by pests and the left strut was severely damaged by some deep cracks and pests. The metal bands were remained on the side and bottom of the box, and all the bands were seriously corroded. On the bottom-right of the lid, black foreign matter was adhered to the surface. In the process of conservation treatments, the cleaning, filling cracks, reinforcing the bottom of the box, attaching the metal bands were proceed in order after the investigation of the state.

• Horticultural Science & Technology
• /
• v.30 no.1
• /
• pp.93-96
• /
• 2012

'Double Shine', a cultivar of Gypsophila paniculata was newly developed for the cut flowers by Jeollabuk-do Agricultural Research & Extension Services. It has morphological characteristics of the spreading plant type, double florets of many petals and two pistils, emarginate petal tip and cup shaped calyx. Also 'Double Shine' has several traits such as strong flower stalk, bright colored flower, narrow branching angle and more or less resistance to powdery mildew and pest injury. Furthermore, 'Double Shine' produced higher primary branches, and longer flower stalk length with internodal length and than did a check variety 'Bristol Fairy' during summer cultivation in subalpine areas. Blooming of 'Double Shine' was delayed by 16 days, its floret had broader width, compared to 'Bristol Fairy'. Moreover, 'Double Shine' produced normal flowers with two pistils and 8.5 stamens, with little production of malformed flowers in the high temperature condition.

• Journal of Conservation Science
• /
• v.31 no.3
• /
• pp.215-225
• /
• 2015

"Jocheonillgi", one of the articles left by Jo Heon(1544~1592) whose pen name was Jung-bong, is a travelogue which was written in around 1574~1575 when he was dispatched to Ming as a formal envoy(Giljungkwan). The diary-style manuscript was designated as one of the pieces of the National Treasure 1007. Due to the damage of its binding strings, abrasion, fold, stain, insect and damage on the surface, conservation and restoration was needed. In the process of separation, three more binding strings were found, confirming that the travelogue was rebound at least twice in the past. In addition, the page of 'Yeondoillgi', the original title, was bound inside, confirming that the current cover was revised in the past. As the result of the investigation of base fabric, paper mulberry was found to be the cover, inside paper, lining paper, paper strings. The three kinds of binding string including the current ones was defined to be silk.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.30 no.1
• /
• pp.9-14
• /
• 2010

This experiment was carried out to know adaptability and forage production and quality of sorghum and sorghum $\times$ sudangrass and sudangrass hybrids at paddy field from 2007 to 2008 at Chungnam province. Among growth characters, 'Sordan 79' hybrid was somewhat strong for waterlogging, and higher sugar content and good at the 2nd regrowth, disease and insect resistance. Fresh yield of 'Sordan 79' hybrid was the highest as 92,492 kg per ha among 10 Sorghum and Sorghum $\times$ Sudangrass hybrids. The dry yield of 'Sordan 79' hybrid was also the highest as 21,090kg per ha. The result of this study showed that 'Sordan79' hybrid had good growth characters and forage productivity and crude protein (CP) and in vitro dry matter digestibility (IVDMD) at paddy field in middle region of South Korea.

• Korean Journal of Plant Resources
• /
• v.10 no.2
• /
• pp.159-164
• /
• 1997

Field experiment for two years was conducted at Ulleung island to determine the optimum planting date and density of Cnidium officinale Makino. Early planting(Mar. 20) showed the highest yield by 2,880kg per ha as dry wt. Planting time after Mar. 20 was decreased. Late planting had higher occurrence of diseases and insect damage. Early planting had higher extract contents than late planting without violation of the Korean crude drug regulation such as ash contents. Although plants grew better in lower density, they had fewer growing points per plant which actually determine the yield components. Planting density did not affected extract contents in Cnidium officinale Makino. High density planting($35\times15cm$)yielded 33% than those of lower planting density($45\times25cm$).

• Korean Journal of Organic Agriculture
• /
• v.22 no.2
• /
• pp.269-280
• /
• 2014

This study was performed to test the insecticidal and antimicrobial activity of plant extracts from clove, Sophora flavescens Aiton and neem. As the result of antimicrobial activity test, clove extract showed the strongest activity against Botrytis cinerea. In insecticidal activity test, the extract of Sophora flavescens Aiton was the highest against Nilaparvata lugens. The pyroligneous liquor (10%) and emulsified spreader (10%) were added to the extracts of clove and Sophora, respectively, to apply the environment-friendly rice field. In the field treated clove extract, disease damage occurred 49.1% and insect damage occurred 29.5% compared to control plot (100%). In the field treated Sophora extract, disease damage was 56.7% and insect damage was 21.0% compared to control plot (100%). In conclusion, plant extracts from Sophora and clove could control about 50% of disease and about 70% of insect damage that they could be used as environment-friendly resources to control disease and insect in rice farming.