• Title/Summary/Keyword: Agricultural R and D

Search Result 1,363, Processing Time 0.031 seconds

Xylogone sphaerospora, a New Fungal Pathogen of Cultivated Ganoderma lucidum (영지의 새로운 병원성진균 Xylogone sphaerospora)

  • Lee, Jong-Kyu;Choi, Gyung-Ja;Cho, Kwang-Yun;Oh, Se-Jong;Park, Jeong-Sik
    • The Korean Journal of Mycology
    • /
    • v.24 no.4 s.79
    • /
    • pp.246-254
    • /
    • 1996
  • Since the mid of 1980's, cultivation area and production of Ganoderma lucidum have been increased annually in Korea. However, the presence of a fungal disease has become a major limiting factor in the cultivation of Ganoderma lucidum, causing a serious economic loss. The present study was carried out to isolate and identify the pathogenic fungus to Ganoderma lucidum. Several fungi isolated from the wood logs showing typical symptoms were tested whether they are pathogenic to Ganoderma lucidum or not by cross-pairing culture method, flask inoculation method, and wood log inoculation method. The pathogenic fungus produced ascomata. Mature ascomata was spherical, dark, thick-walled, 4595μm diameter. Asci were thin-walled, evanescent when mature, disintegrate early. Ascospores were spherical, hyaline, glaborous, thick-walled, refractive, 3.64.3μm in size. Conidiophores soon became abundantly septate and broke up into arthrospores, which are cylindrical, 36μm long and 34μm wide. Based on the observations under dissecting microscope, light microscope and scanning electron microscope, teleomorph and anamorph of the pathogenic fungus were identified as Xylogone sphaerospora Von Arx & Nilsson and Sporendonema purpurascens (Bonordon) Mason & Hughes, respectively. X. sphaerospora is first reported as a pathogenic fungus of Ganoderma lucidum.

  • PDF

Development of Biologically Active Compounds from Edible Plant Sources XIV. Isolation and Identification of Flavonoids from the Aerial Parts of Sajabalssuk (Artemisia herba) (식용식물자원으로부터 활성물질의 탐색-XIV. 사자발쑥(Artemisia herba)의 전초로부터 flavonoid 화합물의 분리)

  • Bang, Myun-Ho;Kim, Dong-Hyun;Yoo, Jong-Su;Lee, Dae-Young;Song, Myoung-Chong;Yang, Hye-Joung;Jeong, Tae-Sook;Lee, Kyung-Tae;Choi, Myung-Sook;Chung, Hae-Gon;Baek, Nam-In
    • Applied Biological Chemistry
    • /
    • v.48 no.4
    • /
    • pp.418-420
    • /
    • 2005
  • In order to search for biologically active compounds from edible plant sources, the aerial parts of Sajabalssuk (Artemisia herba) were extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and H2O, successively. From the EtOAc fraction, four compounds were isolated through the repeated silica gel and ODS column chromatographies. From the results of physico-chemical data including NMR, MS and IR, the chemical structures of the compounds were determined as eupatilin (1), jaceosidin (2), apigenin (3) and eupafolin (4). Among them, compounds 3 and 4 were isolated for the first time from Sajabalssuk (Artemisia herba).

Analysis of Fire Direction and Pine Tree Survival using to Fire Scar formed in Tree Stem after forest Fire (산불발생 후 불자국을 이용한 소나무 생존 및 지형에 따른 산불의 방향 분석)

  • 채희문;이찬용
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.5 no.1
    • /
    • pp.30-35
    • /
    • 2003
  • The study of the scars formed on the bark of pine trees damaged by forest fire was carried out in the burned area of Samchuk and Donghae in 2000. Fire scars were formed on the bark of trees when fire passed by the tree. Fire scarring is usually found on the windward and leeward sides of the tree. Fire spread was analyzed topographically using the fire scars formed at the tree stem. Fire spread was closely related to the shape, slope and direction of the forestland. Four fire direction types are classified according to the shapes of the forestland. The height of the fire scar was higher on the leeward side than on the windward side of the trees studied. The burnt area of the total bark of the tree was over 30% in dead trees and below 12% in living trees. The regression model of the burnt stem area using the height of the fire scar, the diameter of breast height and the height of tree was Y=-2.484×Height+0.04199×D.B.H-1.686×Windward+11.172×Leeward+23.432(r=0.936, F=409.968, P>0.0001).

An Evaluation Method for Sesame (Sesamum indicum L.) Resistance to Phytophthora nicotianae var. parasitica (참깨발병 품종저항성 검정방법 연구)

  • Seong Ho, Choi;Eui Kyoo, Cho;Young Am, Chae
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.32 no.2
    • /
    • pp.173-180
    • /
    • 1987
  • Symptom development and disease severity of Phytophthora blight in the sesame plants varied depending upon age of the plants tested, inoculation method, watering method, and inoculum density in both susceptible Suweon 9 and Suweon 26 and moderately resistant B-67 and IS 103 sesame lines to Phytophthora nicotianae var. parasitica when inoculated. However, successful differentiation of the sesame lines for varietal resistance was possible using 20-day old seedling, inoculation by soil infestation, saturated soil water condition by half immersion of pots in water tank, and 200 sporangia per one ml of inoculum. Spraying or soil inoculation to 70-day old plants also was effective in differentiating the varietal resistance. By the screening method Suwon 26 showed 100% diseased plants and symptom severity index 9.0, while B-67 showed 20% diseased plants and symptom severity index 1.7. The rating scale given was from 0 through 9. For example, the scale 0 signified no symptom development, 5 signified discoloration of basal part of stem, and 9 signified discoloration of stem more than 10 cm high above the soil surface with blighted leaves. Differentiation in symptom severity also was made by percentage of the lesion area. Results evaluated using both parameters were well corresponded in varietal reaction of sesame to Phytophthora blight.

  • PDF

Intergeneric Transfer of Isolated Nuclei from Lentinus edodes into Protoplasts of Pleurotus florida (사철느타리버섯 원형질체내에 표고 핵의 전이)

  • Yoo, Young-Bok;Shin, Pyung-Gyun
    • The Korean Journal of Mycology
    • /
    • v.24 no.2 s.77
    • /
    • pp.111-126
    • /
    • 1996
  • Transfer of the isolated nuclei from Lentinus edodes into protoplasts of Pleurotus florida was induced with polyethlene glycol (PEG) and CaCl2. The intergeneric transfer products were classified into nuclear hybrid, heterokaryon or synkaryon, and reconstituted cell. These progenies except nuclear hybrids formed mature fruiting bodies on sawdust rice bran medium. Formation of fruit bodies was influenced by several factors such as light, temperature, nutrition and physic state of the culture media. Most of fruiting body characters were similar to those of P. florida in synkaryon and L. edodes in reconstituted cell, respectively. All these basidiocarps had clamp connections though initial heterokaryon colonies were lacking. Isozyme patterns of intergeneric progenies were quite different from those of parents. DNA polymorphisms of transfer products were also compared by random amplified polymorphic DNAs (RAPD) analysis based on polymerase chain reaction. The RAPD patterns were different from those of donor and recipient. DNA fingerprints ranged in size from 0.25 to 4.0 Kb. On the basis of RAPD, the transfer products were classified into five groups. Two synkaryon were analysed with distribution of progenies and segregation of genetic markers by random spore analyses. The genetic markers were segregated into wild type and riboflavine requiring auxotrophs.

  • PDF

Actual Evapotranspiration of Sesame Crop Cultured With and Without Transparent Plastic Film Mulch (투명(透明) 프라스틱 필름 피복(被覆)에 따른 참깨의 실증발산량(實蒸發散量) 변화(變化))

  • Oh, Dong-Shin;Kwon, Yong-Woong;Im, Jung-Nam;Ryu, Kwan-Shig
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.29 no.1
    • /
    • pp.34-43
    • /
    • 1996
  • Determining the actual evapotranspiration(ETa) of a crop, and appropriate water management of the crop based on the ETa are very important For increasing the yield. The present study aimed at determining ETa and crop coefficient of sesame growing under different climatic conditions with the transparent thin polyethylene film mulch(0.03 mm thick) and without this mulch. Bottomless cylindrical lysimeters(105cm in diameter, 120cm in height, protruded 20 cm above the soil surface) were installed on the field of sandy loam "Bonyang series" soil with a moderate drainage. The determination of ETa was performed by measuring each component of a model equation, ETa=(R+I){Ro+(D1+D2)}+C±ΔS. Sesame, cv. "Ansan" was sown in two rows with the spacing of 50×15cm on May 10 in 1991 and 1992. The mulching covers 80% of the soil surface. Sesame consumed the water of 139.0 mm(1.53 mm/day) and 171.2 mm(1.59 mm/day) in ETa without the film mulch, but that of 132.6 mm(1.46 mm/day) and 199.8 mm(1.85 mm/day) with its mulching through both years of 1991 and 1992, respectively. The ETa's accounted for 52 and 69% of the potential evapotranspiration(ETp) in the mulched crop, and 54 and 59% of ETp in the non-mulched crop 1991 through 1992, respectively. Its ETa's were much more and their gap between the mulching and non-mulching treatment was larger in 1992 than in 1991 as a result of the better climatic condition of 1992.

  • PDF

Isolation and Characterization of Bacillus Species Having Antifungal Activity Against Pathogens of Ginseng Damping Off (인삼모잘록병원균에 항균활성을 갖는 Bacillus 균의 분리 및 특성조사)

  • Park, Kyeong Hun;Park, Hong Woo;Lee, Seong Woo;Lee, Seung Ho;Myung, Kyung Sun;Lee, Sang Yeob;Song, Jaekyeong;Kim, Young Tak;Park, Kyoung Soo;Kim, Young Ock
    • The Korean Journal of Pesticide Science
    • /
    • v.20 no.4
    • /
    • pp.380-387
    • /
    • 2016
  • This study was performed to select potentially available biological control agent from soil bacteria for prevention of ginseng damping off. More than five hundred strains were isolated from ginseng rhizosphere soil. By testing antifungal activity, we have selected three soil bacteria strains and their ability to produce antibiotics and lytic enzymes such as cellulase, protease and pectate lyase was examined. Also, the presence of genes for biosynthesis of lipopeptide such as fengycin, bacillomycin D, surfactin, iturin A, and zwittermicin A was investigated in selected strains. All three strains produced cellulase, protease, and xylanase. Moreover, these strains had gene for biosynthesis of bacillomycin D, surfactin, and iturin A. ES1 and ES3 strains were identified Bacillus methylotrophucus and ES2 was confirmed Bacillus amyloliquefaciens using phylogenetic analysis on the basis of 16S rRNA gene sequences. In field test, control value of ES1, ES2 and ES3 treatment was 32.4%, 46.8% and 36.7%, respectively. This results indicate that antagonistic microbes with high ability of antifungal and lytic enzyme activity can be used as a useful biological control agent to control ginseng damping off.

Development of Biologically Active Compounds from Edible Plant Sources-XIX. Isolation of Inhibitory Compound on LDL-Oxidation from the Aerial Parts of Sajabalssuk (Artemisia princeps PAMPANINI, Sajabalssuk) (식용식물자원으로부터 활성물질의 탐색-XIX. 사자발쑥(Artemisia princeps PAMPANINI, Sajabalssuk)의 전초로부터 저밀도 지질 단백질(LDL) 산화 억제물질의 분리)

  • Bang, Myun-Ho;Song, Myoung-Chong;Han, Min-Woo;Lee, Dae-Young;Jo, Jin-Kyung;Chung, Hae-Gon;Jeong, Tae-Sook;Lee, Kyung-Tae;Choi, Myung-Sook;Baek, Nam-In
    • Applied Biological Chemistry
    • /
    • v.50 no.3
    • /
    • pp.224-227
    • /
    • 2007
  • Sajabalssuk (Artemisia princeps PAMPANINI) was extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and H2O, successively. From the EtOAc fraction, two phenylpropanoids were isolated through the repeated silica gel and ODS column chromatographies. From the results of physico-chemical data including NMR, MS and IR, the chemical structures of the phenylpropanoids were determined as eugenol (1) and (-)-sesamin (2). They were the first to be isolated from Sajabalssuk (Artemisia princeps PAMPANINI, Sajabalssuk). Also, eugenol inhibited LDL-oxidation with the inhibitory activity of 87.8 ± 1.0% at a concentration of 40 μg/ml.

Adsorption Characteristics of Dimetridazole Antibiotics on Activated Carbon Prepared from Agricultural Waste Citrus Peel (폐감귤박 활성탄을 이용한 항생제 Dimetridazole의 흡착특성)

  • Lee, Chang-Han;Kam, Sang-Kyu;Lee, Min-Gyu
    • Korean Chemical Engineering Research
    • /
    • v.55 no.6
    • /
    • pp.798-806
    • /
    • 2017
  • A activated carbon (WCAC, waste citrus activated carbon) prepared from an agricultural waste citrus peel material generated in Jeju was utilized for the removal of dimetridazole (DMZ) antibiotics in aqueous solution. The adsorption of DMZ on WCAC was investigated with the change of various parameters such as contact time, dosage of WCAC, particle size of WCAC, temperature, pH, and DMZ concentration. The DMZ adsorption capacity increased with increasing temperature and decreasing particle size. Also it was decreased at less than pH 4 but sustained almost constantly at pH 4 or greater. Isotherm parameters were determined from the Langmuir, Freundlich, Redlich-Peterson and Duinin-Radushkevich (D-R) isotherm models. The isotherm data were best described by the Redlich-Peterson isotherm model. And the adsorption kinetics can be successfully fitted to the pseudo-second-order kinetic model. The results of the intra-particle diffusion model suggested that film diffusion and intra-particle diffusion were occurred simultaneously during the adsorption process. Meanwhile, the thermodynamic parameters indicated that the adsorption reaction of DMZ on WCAC was an endothermic and spontaneous process. The experimental results showed that WCAC is a promising and cheap adsorbent for the removal of DMZ antibiotics.

Studios on the Parasites of the Rice Planthoppers I. Egg Parasitism Anagrus nr. flaveolus WATERHOUSB (Hymenoptera : Mymmaridae) on the Rice Planthoppers (멸구 매미충의 기생성 천적에 관한 연구 I. Anagrus nr. flaveolus의 멸구류 난기생에 관하여)

  • Kim J.P.;Yoo C.Y.;Kim C.H.
    • Korean journal of applied entomology
    • /
    • v.21 no.2 s.51
    • /
    • pp.87-94
    • /
    • 1982
  • The mymarids egg parasite of rice planthopper, Anagrus nr. flaveolus, were investigated to know their parasitic activities after overwitering in the paddy banks and barley fields, their host preferences and seasonal variations in the pesticide sprayed and unsprayed paddy fields of Gyeongnam province O.R.D. at Jinju from 1977 to 1979. The parasitic activities of Anagrus nr. flaveolus after overwintering in the paddy banks were high early in April and tended to decrease remarkably since mid-April by moving to the barley fields. The parasitic rate of Anagrus nr. flavelous was 47.2\~88% between middle and late in April, the peak of egg deposition period. Anagrus nr. flaveolus parasitized Laodelphax striatellus, Nilaparvata lugens, and Sogatella furcifera, but didn't attack the eggs of Nephotettix cincticeps in the paddy fields. High preference was observed with Laodelphax steriatellus. The parasitic activities of Anagrus nr. flaveolus in the pesticide sprayed paddy fields were high in early July and from late August to early September. The parasitic rate in the pesticide unsprayed fields were higher than those of sprayed fields during the pesticide spraying period, from July to August and parasitic activities were active from October to before coming winter.

  • PDF