• Korean Journal of Veterinary Service
• /
• v.43 no.2
• /
• pp.107-112
• /
• 2020

Foot-and-mouth disease (FMD) and avian influenza (AI) are highly pathogenic viral disease which affects the livestock industry worldwide. Outbreak of these viruses causes great impact in the livestock industry; thus, disease infected animals were immediately disposed. Burial is the commonly used disposal method for deceased animals. However, there is potential for secondary environmental contamination, as well as the risk that infectious agents persisting in the environment due to the limited environmental controls in livestock burial sites during the decomposition of the carcasses. Therefore, this study aimed to investigate the detection of FMD and AI viruses from animal carcass disposal sites using real-time reverse transcription PCR. Soil samples of more than three years post-burial from livestock carcass disposal sites were collected and processed RNA isolation using a commercial extraction kit. The isolated RNA of the samples was used for the detection of FMDV and AIV using qRT-PCR. Based on the qPCR assay result, no viral particle was detected in the soil samples collected from the animal disposal sites. This indicates that 3 years of burial and their carcass disposal method is efficient for the control or at least reduction of spread infections in the surrounding environment.

• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.5
• /
• pp.866-871
• /
• 2011

An auxin-producing bacteria (3YN11-02) was isolated from waste mushroom bed from Agaricus bisporus of Chungnam Buyeo-Gun area. The strain 3YN11-02 was identified as a novel species belongs to Rahnella aquatica by a chemotaxanomic and phylogenetic nalysis. The isolate was confirmed to produce indole-3-acetic acid (IAA) which is one of auxin hormone by TLC and HPLC analysis. When the concentration of IAA was assessed by performing HPLC quantity analysis, the maximal $290mg\;L^{-1}$ of IAA detected in ether fraction extracted from the culture filtrate which was cultured in R2A broth containing 0.1% tryptophan for 24 h at $35^{\circ}C$. The molecular weight of the main peak obtained by LC-mass analysis was correspondent well to 175, that of IAA. To investigate the growth promoting effect of crop, when the culture broth of R. aquatica 3YN11-02 was infected onto water culture and seed pot of mung bean, the adventitious root induction and root growth of mung bean were 2.0 times higher than control.

• Korean Journal of Soil Science and Fertilizer
• /
• v.43 no.6
• /
• pp.1002-1007
• /
• 2010

The study was performed to investigate the influence on growth and development of grape-cuttings by arbuscular mycorrhizal (AM) fungi inoculation, AM colonization rate, and the phenomena of mycorrhizal association. Among the grape-cuttings, 'Kyoho' and 'Tamnara' cultivars inoculated with AM fungi showed significantly increase of leaf area, leaf number, total root length and root surface area than non-infected ones. But 'Cambell Early' did not showed any significant difference in total root length and root surface area even after the inoculation. The AM colonization rates in mycorrhizal inoculation treatment were 22.5-32.5% in total average after 8weeks, and were 29.6%, 28.8%, and 48.8% for 'Cambell Early', 'Tamnara', and 'Kyoho' respectively after 12weeks. The AM colonization rate marked very low level in non-colonization control plot.

• Proceedings of the Korean Society of Plant Pathology Conference
• /
• 2003.10a
• /
• pp.65.2-65
• /
• 2003

To protect the plant against several soil-borne pathogens, we are currently constructing disease-resistant transgenic root stock for the growth of cucurbitaceae vegetable plants, watermelon and gourd. We made a watermelon cDNA library from Cladosporium cucumerinum-Infected leaves for substractive hybriazation and differential screening. We isolated the several pathogen inducible cDNA clones, such as caffeoyl-CoA-methyltransferase, LAA induced protein, receptor-like kinase homolog, hydroxyproline-rich glycoprotein, catalase, calmodulin binding protein, mitochondrial ATPase beta subunit, methyl tRNA synthetase and WRKY transcription factors. We previously obtained CaMADS in pepper and galactinol synthase ( CsGolS) in cucumber that were confirmed to be related with disease-resistance. CaMADS and CsGolS2 were transformed into the inbred line 'GO701-2' gourd, the inbred line '6-2-2' watermelon and the Kong-dye watermelon by Agrobacterium tumerfaciens LBA4404. Plant growth regulators (zeatin, BAP and IAA) were used for shoot regeneration and root induction for optimal condition. Putative transgenic plants were selected in medium containing 100mg/L kanamycin and integration of the CaMADS and CsGO/S2 into the genomic DNA were demonstrated by the PCR analysis. We isolated major soil-borne pathogens, such as Monosporascus cannonballus, Didymella bryoniae, Cladosporium cuvumerinum from the cultivation area of watermelon or root stock, and successfully established artificial inoculation method for each pathogen. This work was supported by a grant from BioGreen 21 program, Rural Development Administration, Republic of Korea.

• Research in Plant Disease
• /
• v.16 no.1
• /
• pp.21-26
• /
• 2010

Viral diseases, especially Barley yellow mosaic virus (BaYMV) and Barley mild mosaic virus (BaMMV) have been most serious in barley fields. In this study, we investigated the effect of different level of resistance to viral diseases on the plant growth and yield in malting barley. In diagnosis of virus infection, BaYMV and BaMMV were detected in 'Doosan 29' (susceptible), however, 'Jinyangbori' (moderate susceptible) and 'Hopumbori' (moderate) was infected by only BaYMV. Plant height was restrained about 8~29% in overwintered plant regeneration stage depending on the resistant of each cultivar. The culm length damaged also to 9~12% by BaYMV infection. The tiller numbers reduced to 10~14% in overwintering season, however, the head numbers in harvest season more decreased to 26~33%. Heading date was delayed to 3~3 days by the infection. In examination of yield components, 1,000 kernel weight and $\ell$ weight reduced according to culrivar's resistant degrees to 4.0~6.4% and 1.0~4.2%, respectively. The yield of abortive grain was doubled in BaYMV infection comparing to non-infested field. Three varieties tested in the non-infected field over two years were not significantly different for yield potential with ranges of 509kg~632kg/10a. However, significant yield reduction was observed in 'Saessalbori' and 'Baegdong' with ranges of 77~177kg/10a as compared to 'Hopumbori' (467 kg/10a) when tested in the virus-infected field. Yield potentials of these cultivars reduced by 26~43%, respectively, in the virus-infected field as compared to those in the non-infected field.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.61 no.1
• /
• pp.9-16
• /
• 2016

To investigate the effect of soluble silicate zeolite dressing of the rice against bakanae disease, field trial in reclaimed land and in vitro were carried out. The coated rice seeds (SCS) which were dressed with the mixture of 25% silicic acids (binder), and the zeolite (coating powder). In wet direct seeding, uniform scattering of rice seeds on the soil surface and the better seedling establishment were shown in SCS treatment plots. The incidence of bakanae disease began from the mid tillering stage toward the heading stage. Around heading stage, the ratio of infected tillers reached its highest point by 9.9% in non-SCS treatment plots. While, in SCS treatment plots, the ratio of infected tillers was no more than 0.01%. The vitality of the pathogenic fungi of bakanae disease in the SCS and non-SCS samples were assessed. Samples were incubated for one week keeping proper humidity at $30^{\circ}C$ after inoculated with panicles of infected rice plants from experimental field plots. In non-SCS treatment, pinkish colonies were formed on the grain surface of panicle of infected plants, and mycelium, macro-conidia and micro-conidia were developed actively inside part of infected grain inoculated. While in SCS treatment, micro-conidia and mycelium were not survived and the growth of macro-conidia, mycelia were greatly inhibited and withered. Based on the results, it is concluded that the environmental friendly control of bakanae disease by use of SCS is possible and soluble silicate can be applied as agents for replacement of seed disinfection.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.32 no.3
• /
• pp.237-244
• /
• 2012

Barley yellow mosaic virus (BaYMV) and Barley mild mosaic virus (BaMMV) cause severe diseases in winter barley in Europe and East Asia. We investigated the effect of different level of resistance to virus disease on the plant growth and yield in whole-crop barley. In the virus infection, BaYMV was detected all tested cultivars in first diagnosis at 30th March. BaYMV infection was identified only in the susceptible Sunwoobori in 6th April, but not in the Yuyeon (moderate, M) and Youngyang (moderate resistant, MR) cultivars. Plant height was restrained about 14.6~32.9% in overwintered plant regeneration stage depending on the resistance of each cultivar. The tiller numbers also reduced to 8.7~19.7% by BaYMV infection in overwintering season. We evaluated culm length, spike length, and spike number in the virus-infected field and non-infected field. For the culm length, Youngyang (MR) reduced only 14.5% by BaYMV. However Sunwoo (susceptible, S) and Yuyeon (M) cultivars were decreased to 24.8~42.7%. The spike length and spike number also affected to 8.9~21.3% and 24.3~31.0%, respectively, depending on the resistance. After harvesting, dry-matter yield of whole crop yield reduced by approximately 21.6~58.0% according to cultivar resistant degrees. For example, Sunwoobori (S) decreased 58.0% in comparing to non-infected field. The grain yield was also significantly reduced in virus infected cultivars. Sunwoobori (S) was severely decrease more than 60.0%. Yuyeonbori (M) and Youngyangbori (MR) also decreased 30.0~47.5% by the viral infection comparing to those in the non-infected field.

• The Korean Journal of Mycology
• /
• v.20 no.4
• /
• pp.337-346
• /
• 1992

Trichoderma spp. are an effective control agent for damping-off or other plant diseases. The interaction between. T. hamatum and Rhizoctonia solani on the rhizosphere or surface soil were examined to assess the possible roles of antibiosis or competition in the mechanisms of biological control agents as a basic research. In a proportional comparison, total bacteria, fungi, actinomycetes and Trichoderma spp were 65%, 8.8%, 25.9% and 0.28% respectively in their distribution in the soil. Among Trichoderma spp isolated, the 5 species of Trichoderma spp were indentified as T. koninggii, T. pseudokoninggii, T. aureoviridi, T. hamatum and T. viride respectively. In a mycoparasitic test, one isolate of T. hamatum strain Tr-5 showed an enzymatic ability to break fungal hyphae into piecies and infected on the R. solani hyphae showing a parasitism. Spore germination of the all isolates of Trichoderma spp showed a 1.7-7.3% of germination in natural soil conditions, but the percentage was high in sterile soil indicating all the natural soil were fungistatic on conidia of Trichoderma spp. In rhizosphere competent assay in pea plant, the antagonistic T. hamatum, T. viride, T. koninggii, T. pseudokoninggii showed a colonizing upper soil depth in rhizosphere around 1-3 cm in root zone, but the colonizing ability was much reduced along the deeper the soil depth. Propagule density was decreased in deeper the soil layer. Disease development rate treated alone with plant pathogens, Fusarium solani, Rhizoctonia solani, Cylindrocarpon destructans increased, but disease incidence rate reduced in treatment with combinations with antagonistic T. hamatum strain Tr-5.

• Journal of Korean Society of Forest Science
• /
• v.65 no.1
• /
• pp.43-47
• /
• 1984

Pinus rigida ${\times}$ P. taeda seedlings in a nursery was inoculated with basidiospores of Pisolithus tinctorius (Pt) either collected from Suweon, Korea or introduced from U.S.A. to compare the effectiveness of the spores from two different origins as mycorrhizal inocula. Nursery beds were fumigated with methyl bromide and 1g of spores was used to inoculate $1m^2$ of soil surface just before seed sowing. Seedlings inoculated with American Pt (#250 strain from Georgia, U.S.A.) were 15% taller than Korean Pt at the end of the first growing season. The seedlings from fumigation treatment only (no inoculation involved) was slightly taller (statistically unsignificant) than those with Korean Pt, but slightly smaller than those with American Pt. In a subsequent year experiment, the seedlings inoculated with American and Korean Pt after soil fumigation were 66% and 60% taller, respectively, than seedlings infected by natural fungi without soil fumigation, suggesting the dual effects of Pt and fumigation on the seedling growth. Therefore potential of Pt spores for an effective inoculum exists and selection of Pt strains which have adapted to specific local environments is needed to develop better sources of mycorrhizal inocula.

• Korean Journal of Plant Resources
• /
• v.27 no.2
• /
• pp.194-201
• /
• 2014

This study was carried out to investigate the characteristics and infection effects of AMF with soil samples collected at some sites in Gyeonggi province, Korea. AMF spore and characteristics of infection structure in upland plant root were observed as wet sieving and staining method, growth of Capsicicum annum was compared between treatment and non treatment. AMF spores isolated from each soil sample were ellipse or circle type and the colors were soft yellow and white. The colonization rate of AMF with soil infection of Zea mays roots was 13.3~83.3%, the rate of infected soil collected from Z. mays was higher on average. When compared to the growth of C. Annum with control after infection on C. annum, it wasn't showing many differences in fresh weight, dry weight and height, but the yield of fruit of C. annuum showed double than the control group.