• The Plant Pathology Journal
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• v.39 no.4
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• pp.409-416
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• 2023

Bacterial leaf blight of carrots caused by Xanthomonas hortorum pv. carotae (Xhc) is an important worldwide seed-borne disease. In 2012 and 2013, symptoms similar to bacterial leaf blight were found in carrot farms in Jeju Island, Korea. The phenotypic characteristics of the Korean isolation strains were similar to the type strain of Xhc. Pathogenicity showed symptoms on the 14th day after inoculation on carrot plants. Identification by genetic method was multi-position sequencing of the isolated strain JJ2001 was performed using four genes (danK, gyrB, fyuA, and rpoD). The isolated strain was confirmed to be most similar to Xhc M081. Furthermore, in order to analyze the genetic characteristics of the isolated strain, whole genome analysis was performed through the next-generation sequencing method. The draft genome size of JJ2001 is 5,443,372 bp, which contains 63.57% of G + C and has 4,547 open reading frames. Specifically, the classification of pathovar can be confirmed to be similar to that of the host lineage. Plant pathogenic factors and determinants of the majority of the secretion system are conserved in strain JJ2001. This genetic information enables detailed comparative analysis in the pathovar stage of pathogenic bacteria. Furthermore, these findings provide basic data for the distribution and diagnosis of Xanthomonas hortorum pv. carotae, a major plant pathogen that infects carrots in Korea.

• Korean Journal of Agricultural Science
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• v.12 no.2
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• pp.199-205
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• 1985

1. Alternaria tenuis, Cladosporium cladosporioides, Curvularia lunata Fusarium semitectum, Gerlachia oryzae, Phoma sp. Trichoconiella padwickii were found associated with ear blighting of rice plants. The frequency of isolation of the fungi was found to be higher from the severely discolored rice grains than that from the brownish spotted grains, but H. oryzae was encounted highly from the latter. 2. Higher counts of Alternaria tenuis, Helminthosporium oryzae, Trichoconiella padwickii, Fusarium moniliforme, Fusarium semitectum were observed under alternating cycles of 12hrs of light and darkness than under complete darkness but G. oryzae was encountered highly under darkness in the blotter. While no difference in the occurrence of the other fungi was recorded under l2hr NUV light-12hr darkness cycles and darkness. 3. A. tenuis and C. cladosporioides were encountered highly at the lower temp. $(15^{\circ}C)$ but Phoma sp. was occurred highly at the higher temp. $(30^{\circ}C)$ when the seeds were incubated in the blotter. 4. Artificial inoculation of the fungi in the ears of rice plants caused severe discoloration of rice grains and reduced 1,000 grain weights and grain ripening percentage.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.3
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• pp.112-117
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• 2000

Food waste is the main source of decay, odors and leachate in collection, transportation and landfill due to the high volatile solids (VS) and moisture content. Acidogenic fermentation of food waste is affected by the fermentation constraints including the biodegradability of substrate and the degrading capability of microorganisms. The biodegradability of food waste is mainly related to cellulosic materials, which are hardly degraded and comprise about 50% of food waste. The efficient and economical method of improving hydrolysis is, therefore, to apply microorganisms with increased cellulose-degrading capability. In this experiment, rumen microorganisms were inoculated to improve the low efficiency of acidogenic fermentation, and then compared with that of mesophilic acidogens. The fermentation of food waste in a leaching bed reactor employing rumen microorganisms resulted in the enhanced acidification (71.2% at $3.0d^{-1}$), which was higher than that (59.8% at $4.5d^{-1}$) employing mesophilic acidogens. This indicated that Rumen microorganisms had an enhanced waste-degrading capability.

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

• Journal of Animal Science and Technology
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• v.46 no.2
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• pp.235-242
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• 2004

A system for the production of transgenic plants has been developed for Italian ryegrass(Lolium mult리orum Lam.) via Agrobacterium-mediated transformation of embryogenic callus. Mature seed-derived calli were infected and co-cultured with Agrobacterium EHA101 carrying standard binary vector pIG121Hm encoding the hygromycin phosphotransferase(HPT), neomycin phosphotransferase II (NPTII) and intron-oontaining $\beta$g1ucuronidase( intron-GUS) genes in the T-DNA region. The effects of several factors on transformation and the expression of the GUS gene were investigated. Inclusion of 200${\mu}M$ acetosyringone(AS) in inoculation and co-cultivation media lead to a significant increase in stable transformation efficiency. Increasing Agrobacterium cell density up to 1.0 in $OD_{600}$ during infection increased transfonnation efficiency of embryogenic calli. The highest transfonnation efficiency was obtained when embryogenic calli were incoulated with Agrobacterium in the presence of 0.1% Tween20 and 200${\mu}M$ AS. Hygromycin resistant calli were developed into complete plants via somatic embryogenesis. GUS histochemical assay and PCR analysis of transgenic plants demonstrated that transgenes were integrated into the genome of Italian ryegrass.

• Korean Journal of Soil Science and Fertilizer
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• v.26 no.3
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• pp.197-203
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• 1993

Greenhouse experiments were conducted to avaluate strain competition, nodulation, patterns of nodule occupancy and population changes of Bradyrhizobium sp. strain HCR-46 $str^{r}cep^{r}$ and CB756 $str^{r}rif^{r}$ in the rhizosphere of peanut(Arachis hypogaea L.) under different root temperatures. Inoculated with two strains using seed coating with peat slurry under different root temperatures, population of each strain in the rhizosphere increased with plant growth and multiplication rate of inoculum in the unit weight of root were showed the highest from 10 to 15days after sowing. The multiplication rate of inoculum in the rhizosphere was $28^{\circ}C$>$34^{\circ}C$>$22^{\circ}C$. The density of HCR-46 $str^{r}cep^{r}$ was more increased than that of CB756 $str^{r}rif^{r}$ under $22^{\circ}C$ and $28^{\circ}C$. While the density of two strains showed no difference under $34^{\circ}C$. Inoculated with HCR-46 $str^{r}cep^{r}$ and CB756 $str^{r}rif^{r}$, respectively at 22, 28 and $34^{\circ}C$, nodulation of each strain was dominated in its inoculation portion. Inoculated with the mixture of HCR-46 $str^{r}cep^{r}$ and CB756 $str^{r}rif^{r}$, occupancy rate of HCR-46 $str^{r}cep^{r}$ was dominated over that of CB756 $str^{r}rif^{r}$ at $22^{\circ}C$ and $28^{\circ}C$, but that was similar between them at $34^{\circ}C$. Dry mass, nodulation, nitrogen content per plant and nitrogenase activity showed higher at $28^{\circ}C$ than at $32^{\circ}C$ and $22^{\circ}C$, while those were higher in HCR-46 $str^{r}cep^{r}$ and mixing HCR-46 $str^{r}cep^{r}$ with CB756 $str^{r}rif^{r}$ than in CB756 $str^{r}rif^{r}$.