• International Journal of Industrial Entomology and Biomaterials
• /
• v.34 no.2
• /
• pp.38-44
• /
• 2017

Mulberry leaves containing 1-deoxynojirimycin (DNJ) have been recognized as a potentially important source for prevent or treat hyperglycemia. However, DNJ content of natural mulberry leaf are as low as 0.1%. Thus, the most effective method for increasing ${\alpha}$-glucosidase inhibitory activity with the DNJ high-production is needed. In this study, we investigated the influence of ${\alpha}$-glucosidase inhibitory activity according to different pH values (6-9) and inoculation amounts (0.1-0.5%) when Bacillus subtilis cultured on mulberry leaf powder media. We confirmed that ${\alpha}$-glucosidase inhibitory activity was difference according to culture conditions of different pH values, inoculation amounts, and fermentation times. The results of mulberry leaf fermentation according to pH values and inoculation amounts were shown that the optimal conditions for ${\alpha}$-glucosidase inhibitory activity were defined as pH 7 and 9, inoculation amount 0.4%, and incubation until 2 to 4 days. These results can be provided a basic data for the optimal culture conditions increasing ${\alpha}$-glucosidase inhibitory activity from mulberry leaf fermentation.

• Mycobiology
• /
• v.31 no.2
• /
• pp.105-112
• /
• 2003

Sclerotia of Grifola umbellata were cultivated by two methods such as burying and root inoculation methods. The sclerotia of G. umbellata produced by the burying method were $6.0{\sim}6.8{\times}3.4{\sim}4.6{\times}1.8{\sim}1.9cm$(Width$\times$Length$\times$Thickness) in size and $17.3{\sim}19.6g$ in weight, respectively. Their increase rate was $1.10{\times}1.12$ times. On the other hand, the sclerotia cultivated by the root inoculation method were $18.3{\sim}31.5{\times}12.5{\sim}26.4{\times}3.1{\sim}3.7cm(W{\times}L{\times}T)$ in size and $219.1{\sim}576.6g$ in weight, respectively. Their growth increment was $11.18{\sim}39.77$ times. The rhizomorphs of Armillaria mellea were developed with a high density under fallen leaves layer covering cultivation site, and distributed mainly between soil surface and soil depth of about 10 cm as well as colonized prominently on the inoculated wood logs. Fungal interaction between G. umbellata and A. mellea were observed mainly in the stage of white sclerotium of G. umbellata. The sclerotia of G. umbellata which were developed newly and harvested in the root inoculation method were twined with root hairs of host tree and rhizomorphs of A. mellea. The sclerotia of G. umbellata decomposing root hairs of host tree were confirmed through SEM examination. Physiochemical characteristics of soil in all cultivation sites had no significant differences. Soil pH were in the range of pH $3.98{\sim}4.40$. Organic matters were the range of $17.97{\sim}23.86%$ and moisture contents of soil were $12.00{\sim}18.20%$. Soil temperatures showed $12.9{\sim}13.8^{\circ}C$ in November and $22.0{\sim}23.9^{\circ}C$ in August, respectively. In conclusion, the root inoculation method seems to be a practical method for cultivating sclerotia of G. umbellata due to its many advantages such as simplicity of inoculation process, shortening of cultivation periods and facility of harvest.

• KSBB Journal
• /
• v.13 no.1
• /
• pp.31-37
• /
• 1998

A simple method for the in vivo production of third-stage infective juveniles(IJs) of Steinernema glaseri was developed. Using Galleria mellonella larvae, only IJs can be rapidly generated inadequate quantities for field application. The nematode inoculation concentration and incubation temperature were critically important. The most effective temperature for infectivity of Steinernema glaseri IJs to Galleria mellonella larvae was 33$^\circ C$. However, the total number of menatodes harvested at 25$^\circ C$ about 66,000 IJs per larva was significantly greater than those at other temperatures. The optimal inoculation number of nematodes was 60 to 80 nematodes per host larva. The higher nematode inoculation concentration of 100 IJs per larva caused a rapid decrease in the total number of IJs harvested. As the inoculation medium pH increased, the number of IJs harvested increased and reached about 110,000 IJs per larva at pH 9.0. The pathogenicity of IJs decreased y increasing the salt concentration in the medium.

• Horticultural Science & Technology
• /
• v.31 no.1
• /
• pp.110-116
• /
• 2013

This study was carried out to establish the simple mass-screening methods for resistant tomato to Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici (FOL). Root dip inoculation method has been used in many studies on the resistance of tomato to disease. On the other hand, in mass-screening for resistant tomato to Fusarium wilt, the inoculation method is time-consuming and laborious procedure. Disease development of two FOL isolates on two cultivars of tomato according to inoculation method including root dip, tip and scalpel methods were investigated. In compatible interaction, tomato seedlings of each cultivar inoculated by tip method showed the lower and more variable disease severities than by root dip method. Whereas the seedlings by scalpel method represented clear resistant and susceptible responses to Fusarium wilt as root dip method. The resistance degree of each cultivar inoculated with FOL isolates by scalpel method was hardly affected by the tested incubation temperature and inoculum concentration. On the basis of the results, we suggest scalpel inoculation method as an efficient mass-screening method for resistant of tomato cultivars to Fusarium wilt. Roots of tomato seedlings at two-leaf stage grown in plastic cell tray were injured with scalpel and then spore suspension (more than $1{\times}10^7\;conidia{\cdot}mL^{-1}$) of FOL was poured directly on the roots. The infected plants were cultivated in a growth room at $25-30^{\circ}C$ for 4 weeks with 12-hours light a day.

• Proceedings of the Korean Society of Plant Pathology Conference
• /
• 2003.10a
• /
• pp.69.2-70
• /
• 2003

For the selection and breeding of chestnut varieties resistant to the chestnut blight fungus Cryphonectria parasitica, disease resistance and susceptibility of 28 varieties widely planted and growing in Korea were evaluated by artificial inoculation of a pathogenic fungus. For this experiment, a typical virulent strain (KCPC-19) was selected. Artificial inoculation was conducted into all varieties by using two different materials and methods, i.e., bark and wood tissue sections in the laboratory and living trees in the field. In the bark and wood tissue section method, the size of necrotic area and canker development on chestnut varieties were examined and compared 4 days after inoculation. There were wide variations of chestnut varieties in disease resistance and susceptibility against chestnut blight fungus, but 3 varieties, Daebo！, Ishizuchi, and Sandae, were shown to be relatively resistant to the disease with the necrotic area of 0.95-1.03 cm2, while Arima was the most susceptible with the size of 2.0 cm2. In the living tree inoculation examined 5 weeks after inoculation, 3 varieties, Daebo, Ishizuchi, and Riheiguri, showed the higher resistance, but Tono 2 did the highest susceptibility among tested varieties.

• Korean Journal of Veterinary Research
• /
• v.33 no.2
• /
• pp.241-247
• /
• 1993

Forty day old piglets were intranasally inoculated with 2ml of Aujeszky's disease virus (NYJ-1-87 strain, $10^{7.0}$ $TCID_{50/0.2}ml$), and the viral antigens were detected in nasal and circulating white blood cells for 20 days after inoculation by immunocytochemical method. Antibody titers in the blood were also detected by neutralizing test and Aujeszky's disease serodiagnostic kit(Choong Ang) in this periods. 1. Viral antigens were detected by the immunocytochemical technigue, and positive reactions were observated in nasal cells from the 2nd to the l0th days after inoculation and circulated white blood cells from the 4th to the 12th days after inoculation. 2. In neutralization test antibodies levels showed titers of 2 on the 8th day, 8 on the l5th day, 16 on the 18th day and 32 on the 20th day after inoculation. In serodiagnostic kit test positive reactions were observed after the 15th day after inoculation.

• Research in Plant Disease
• /
• v.9 no.1
• /
• pp.39-41
• /
• 2003

Bacterial soft rot by Erwinia carotovora subsp. carotovora is one of the diseases causing the biggest damages in Chinese cabbage cultivation. This study was conducted to evaluate disease resistance of Chinese cabbage cultivars and breeding lines to E. carotovora subsp. carotovora by new inoculation method, mineral oil inoculation method, inoculating 10 ml of the mixture (4:1, v/v) of bacterial suspension and mineral oil on the central bases of Chinease cabbage seedling. Total 43 Chinese cabbage cultivars and lines obtained from 3 domestic seed companies and universities were screened for disease resistance using the above mentioned inoculation method. This screening test showed that Chinese cabbage C3-26, C3-28, C3-29 and C29-51-51-53 lines were resistant, Gangta, Gumchonyealgali, Mini, DB50, Jibu, Pyungchng, Sanchon and Yellow King No.2 cultivars were susceptible, and the others were moderate resistant.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.11 no.3
• /
• pp.145-152
• /
• 1991

This experiment was carried out to investigate the effects of liming, manure application, and inoculation with Rhizobium on the early growth, nodulation, seedling establishment, winter survival, and forage yield and quality of alfalfa(Medicago sativa L.) at the Experimental Livestock Farm, College of Agriculture, Seoul National University, Suweon in 1985 and 1986. The results obtained are as follows: 1. Seedling vigor and nodule formation of alfalfa at early stage were the best in the treatments of liminginoculation( L1) and liming-manure-inoculation(LM1). 2. Seedling establishment was not significantly affected by the treatments of liming, manure application, nodulation and the combination of these. 3. The LI and LMI treatments showed the highest winter survival of 94.3 and 83.5%, respectively, but the lowest winter su.rvival of 55.9 and 58.5% was found in no treatment(None) and inoculation( I ), respectively. 4. No differences in crude protein(CP1, acid detergent fiber(ADF) and neutral detergent fiber(NDF) contents were found among the treatments. 5. There were significant differences in the total dry matter yield of alfalfa among the treatments. The total dry matter yields of 10,618, 11,830, 11,855 and 13,456 kg/ha from the treatments of L, LM, LI and LMI, respectively, were significantly higher than those of None, M and I treatments. 6. Based on the results of the experiment, it appears that the dry matter yield of alfalfa could be enhanced by the treatments of liming with Rhizobium inoculation and also liming, manure application and Rhizobium inoculation as a practical method.

• The Plant Pathology Journal
• /
• v.22 no.4
• /
• pp.348-352
• /
• 2006

Barley mild mosaic virus(BaMMV) is a soilborne Bymovirus vectored by root-infecting fungus, Polymyxa graminis. Mechanism of cultivar's resistance to BaMMV in field tests are difficult to assess since resistance could be either due to the virus or to P. graminis, or both. Whereas, available mechanical inoculation methods for BaMMV and other related viruses are labor intensive, give inconsistent results and generally result in low infection rates. Inoculation method using stick with gauze(SWG) was developed for BaMMV. The improved method proved to be simple, efficient, and reliable. The infected leaf tissues were preserved by drying in a frozen state under high vaccum(freeze dried barley infected leaves) to circumvent reduction of virus infectivity during storage. Five Korean barley cultivars were mechanically inoculated with BaMMV-infected sap by the improved method. Infection rates obtained were compared with natural infection. Cultivar Naehanssalbori showed resistance to BaMMV in the field trials but was found highly susceptible in the greenhouse tests by mechanical inoculation, indicating that the field resistance may be possibly due to resistance to P. graminis.

• Korean journal of applied entomology
• /
• v.40 no.1
• /
• pp.51-58
• /
• 2001

Entomopathogenic fungus, Paecilomyces japonicus, has been commercially used as medicinal purpose . The silkworm, Bombyx mori, as an optimal host for the fungi, has been selected and used for the production of the fungal fruit bodies. In current method, newly molted fifth instal larvae should be exposed to the adverse stress environment of high temperature (3$0^{\circ}C$), high relative humidity ( 90%), and starvation for 24h for better fungal inoculation to the host insects. In this study, an alternative method using chemical agent, dexamethasone (DEX: an eicosanoid biosynthesis inhibitor), was tried to get the immunodepressive effect on the larvae to elevate the inoculation rate of the fungi to the silkworm without any harsh rearing environment. DEX (100$\mu\textrm{g}$) showed significantly synergistic effect on the hemocyte lethality of the fungus, and was effective to decrease cellular immune responses measured by the number of hemocyte microaggregation and phenoloxidase activity of the fifth instar larvae in response to the fungal injection. A detergent of 0.05% Triton-X was effective to increase the in- oculation rate of the fungi to the larvae and used in all fungal spraying solutions. Without any environ- mental stress treatment, only DEX (100$\mu\textrm{g}$) injection to the fifth instar larvae followed by the fungal spray was effective to get the inoculation rate equivalent to the current fungal spray method requiring harsh rearing environment. These results suggest that the inoculation of P. japonicus can be elevated by the help of DEX and that the silkworms use eicosanoids to elicit cellular immune response against fungal pathogen.