• The Plant Pathology Journal
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• v.26 no.3
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• pp.267-270
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• 2010

We designed a sensitive and specific PCR-based method with enterobacterial repetitive intergenic consensus (ERIC) primer to detect Erwinia pyrifoliae, which cause shoot blight in Asian pear, from a mixed culture and infected plant materials. The primers specifically detected only E. pyrifoliae and showed no cross-reactivity with other bacterial phytopathogens.

• Korean Journal of Medicinal Crop Science
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• v.4 no.3
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• pp.236-240
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• 1996

1. The pathogenic fungi which infect to shoot of peony was 7 species. The infected parts were as followed, leaf spot disease was in leaf, leaf blotch was stem, powdery mildew was whole aeri­al part of both leaf and stem. 2. The major diseases were leaf spot and powdery mildew, and begin to occur from late April to mid­dle May, and then rapidly heavy infected. The 'Euiseongpeony' variety was more susceptible to those diseases than the 'Yeongcheonpeony' variety. 3. The blight of top part by seasonal in 1995 was begun at late May and increased rapidly 50.6% in Early August.

• Journal of Sericultural and Entomological Science
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• v.16 no.2
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• pp.99-109
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• 1974

These studies aimed to establishment of controlling measure of the bud blight of mulberry tree when intermediate cutting harvest in autumn. The results obtained as following. 1. Effect of chemicals a) Results of 1972 (1) Of the seventeen chemicals tested. according to in vitro, the mycelial growth of Gibberella lateritium f. sp. mori was highly inhibited by PTAB and Benlate. PTAB and Benlate were also highly effective under the conditions of pathogen inoculated to the piece of mulberry tree and fungicidal action of these chemicals were stronger than the others. (2) Topsin-M. organic fungicide and plant growth regulator were not effective to inhibition of mycelial growth. (3) The effectiveness of fungicides were reduced gradually as the time after treatment increased. PTAB and Benlate retained approximately 50 percent of the original activity even after 15 days. (t) Of the twelve chemicals tested in fold, Benlate combination of PTAB with Apion, Apion and PTAB were the most effective fungicides for the control of bud blight of mulberry tree. (5) There is a sigificant difference between the timing on spraying, but it is not greatly effective for the control of bud blight of mulberry tree. b) Results of 1975 (1) Of the ten chemicals tested, according to in vitro RH 893, combination of Benlate with TMTD and TMTD were the most effective to inhibition of mycelial growth, followed by Benlate and combination of Benlate with Topsin M. (2) Of the eleven chemicals tested, Benlate, combination of Benlate with Kinondu, combination of Benlate with Topsin-M and Topsin M were highly effective under the renditions of pathogen inoculated to the piece of mulberry tree. (3) Of the eleven chemical evaluation tests were conducted in 3 experiment fold of Seoul, Chuncheun and Pusan, Benlate, Topsin-M, Apion, TMTD. combination of Benlate with Topsin-M, combination of Benlate with TMTD, combination of Benlate with Apion were highly effective chemicals for the control of bud blight of mulberry tree. (4) There is no difference between the timing on the chemical spraying after intermediate cutting harvest mulberry tree in autumn. 2. Ecological Control. When the mulberry shoot were cut off one to two buds from the top of intermediate cutting from 15th to 30th on October, bud blight of mulberry tree was greatly reduced in next spring compared with the effective chemical spraying. 3. Economical analysis on the results of chemical and ecological tests. When the expenses of ecological control for bud blight of mulberry tree per one ha was 100. thats of chemical control was from 159 to 254 according to spraying machines.

• Journal of Wetlands Research
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• v.13 no.3
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• pp.603-611
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• 2011

In order to enhance cutting efficiency of reed culms, we had assessed diverse methodology in cutting and applied better conditions among them into three vigorous eco-types of common reed. From the results, differences in a eco-type, a sampling area in reed population and substrata affected the shoot emergence slightly. On the other hand, differences in a type of burying culms and a burying part among whole culm affected shoot emergence strongly. Our results suggest that not only methodological condition but also appropriate kind of eco-types must be considered in using reed culms for better cutting. In addition that, sampling timing according to the geological and climatic condition of certain area should be considered for better cutting efficiency as well. We also recommend that the sampling area such as expanding area in a population, burying a middle part of the culm, substratum such as well-ventilated sand and vertical burying method for better cutting efficiency. Lastly, for more enhancement of cutting efficiency of reed culms, potential damages by blight and harmful insects such like aphids should be concerned very carefully.

• The Plant Pathology Journal
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• v.21 no.2
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• pp.127-131
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• 2005

In this comparative study, the effects of temperature, pH, and bactericides on the growth of Erwinia pyrifoliae and Erwinia amylovora were investigated. The maximum temperature for the growth of both Erwinia species was estimated to be $36{\circ}C$. The maximum specific growth rates of E. pyrifoliae and E. amylovora were observed at $27{\circ}C$ and $28{\circ}C$, respectively, and no significant growth differences were shown at their optimum temperatures. However, at lower temperatures ranging from 12-$21{\circ}C$, E. pyrifoliae showed higher growth rates with doubling times shorter than those of E. amylovora. Distinct growth rates at these temperatures revealed that E. pyrifoliae is more cold-tolerant than E. amylovora. The optimum pH for the growth of both pathogens was 7.5 and growth was not seen at pH ${\le}$ 5.0 and ${\ge}$ 10.0. These results showed that the effect of pH on the growth of E. pyrifoliae and E. amylovora was similar. Minimum inhibitory concentrations (MICs) of copper sulfate, oxolinic acid, streptomycin, and tetracycline, which inhibited growth of E. pyrifoliae and E. amylovora, were determined. The strains of both pathogens were able to grow at 0.08-0.32 mM copper sulfate, but not at higher concentrations. However, none of the tested strains grew in the presence of oxolinic acid (0.001 mM), streptomycin (0.1 mM), and tetracycline (0.01 mM) concentrations. These results suggested that all strains of both Erwinia species were sensitive to tested bactericides and indicated no occurrence of resistant strains of E. pyrifoliae in Korea.

• The Korean Journal of Pesticide Science
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• v.13 no.1
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• pp.45-53
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• 2009

An antagonistic bacterial strain KLF01 was isolated from rhizosphere of tomato and identified to be Lactobacillus sp. by biochemical and genetic analysis. This strain showed antagonism against the used plant pathogenic bacteria like Ralstonia solanacearum, (bacterial wilt), Xanthomonas axonopodis pv. citri, (Citrus canker), Xanthomonas campestris pv. vesicatoria (Bacterial spot), Eriwinia pyrifoliae (Shoot-blight) and Eriwinia carotovora subsp. carotovora group (Potato scab) through agar well diffusion method. In planta test done by drench application of strain KLF01 $(4{\times}10^8 cfu/ml)$ into the experimental plot containing tomato (Solanum lycopersicum L.) cultivar 'Lokkusanmaru' and red pepper (Capsicum annuum L.) cultivar 'Buja' plants, in pot test post-inoculated with the plant pathogenic bacteria, R. solanacearum significantly reduced the disease severity, compared to the non-treated plants.

• The Korean Journal of Mycology
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• v.33 no.2
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• pp.98-102
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• 2005

In 2003 to 2005, the root rot of Japanese angelica (Aralia elata) was surveyed in nursery beds of Korea, where incidence of the disease often reached up to 100%. Three isolates were obtained from the infected roots, and identified as Phytophthora cactorum on the basis of cultural, morphological characteristics and molecular analysis. The isolates were characterized by having markedly papillate and broadly ovoid deciduous sporangia. The optimum temperature for mycelium growth was at $25^{\circ}C$ on V8 juice agar. Pathogenicity of the isolates was confirmed by soil mixture inoculation. Approximately 900 bp of ITS rDNA was amplified from all 3 isolates and band pattern of restriction fragments observed by Alu I, Msp I, and Taq I digestion also supported the result of the morphological identification when compared with PhytID database.

• Korean Journal of Agricultural Science
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• v.10 no.2
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• pp.269-276
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• 1983

Out of 50 seed samples of Sesamum indicum L. tested, Alternaria sesami and Corynespora cassiicola were detected in 29 samples and 38 samples, respectively. Heavy infection of A. sesami and C. cassiicola caused seed rot and seedling blight on water agar as well as in pots. In case of light infection the seed germinated showing elongation of the radicle and hypocotyl, but soon light brown or dark brown lesions appeared at certain parts of the shoot and root where sporulation of the fungi was observed after prolonged incubation in moisture. Four seed disinfectants were compared for the control of seed-borne infection of A. sesami and C. cassiicola. Complete control of seed-borne infection of C. cassiicola was obtained by seed treatment with Benlate T and Homai and seed treatment with Busan 30 was found superior to control seed-borne infection of A. sesami.

• Korean Journal Plant Pathology
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• v.13 no.3
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• pp.145-151
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• 1997

An unusual young fruit rot of apple caused by two species of Phytophthora was epidemic from late May to early July of 1996 in Andong, Uisung and Chungwon areas of Korea. The disease spread to over 30 apple orchards in the areas and percent of the infected tree and fruit was ca. 10~90% and 1`15%, respectively. Water soaking lesions or spots on leaves and shoot blight were also developed by the pathogen. Among 39 isolates collected, 25 were identified as P. cactorum and the others were as zp. cambivora on the basis of their distinctive morphological characters. While the former fungus was homothallic, all isolates of the latter were A1 mating types. Koch's postulate was fulfilled. Both fungi showed strong pathogenicity not only to young fruits, leaves and shoots of apple but also to those of pear and peach. Several vegetables tested did not show symptoms even by wound inoculation. An Occurrence of young fruit rot of apple caused by Phytophthora has not been reported in Korea, especially, P. cambivora has not been recorded previously as the causal agent of the disease in the world.

• Molecules and Cells
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• v.25 no.1
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• pp.30-42
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• 2008

The disease-specific (dsp) region and the hypersensitive response and pathogenicity (hrp) genes, including the hrpW, $hrpN_{Ep}$, and hrpC operons have previously been sequenced in Erwinia pyrifoliae WT3 [Shrestha et al. (2005a)]. In this study, the remaining hrp genes, including the hrpC, hrpA, hrpS, hrpXY, hrpL and hrpJ operons, were determined. The hrp genes cluster (ca. 38 kb) was comprised of eight transcriptional units and contained nine hrc (hrp conserved) genes. The genetic organization of the hrp/hrc genes and their orientation for the transcriptions were also similar to and collinear with those of E. amylovora, showing ${\geq}80%$ homologies. However, ORFU1 and ORFU2 of unknown functions, present between the hrpA and hrpS operons of E. amylovora, were absent in E. pyrifoliae. To determine the HR active domains, several proteins were prepared from truncated fragments of the N-terminal and the C-terminal regions of $HrpN_{Ep}$ protein of E. pyrifoliae. The proteins prepared from the N-terminal region elicited HR, but not from those of the C-terminal region indicating that HR active domains are located in only N-terminal region of the $HrpN_{Ep}$ protein. Two synthetic oligopeptides produced HR on tobacco confirming presence of two HR active domains in the $HrpN_{Ep}$. The HR positive N-terminal fragment ($HN{\Delta}C187$) was further narrowed down by deleting C-terminal amino acids and internal amino acids to investigate whether amino acid insertion region have role in faster and stronger HR activity in $HrpN_{Ep}$ than $HrpN_{Ea}$. The $HrpN_{Ep}$ mutant proteins $HN{\Delta}C187$ (D1AIR), $HN{\Delta}C187$ (D2AIR) and $HN{\Delta}C187$ (DM41) retained similar HR activation to that of wild-type $HrpN_{Ep}$. However, the $HrpN_{Ep}$ mutant protein $HN{\Delta}C187$ (D3AIR) lacking third amino acid insertion region (102 to 113 aa) reduced HR when compared to that of wild-type $HrpN_{Ep}$. Reduction in HR elicitation could not be observed when single amino acids at different positions were substituted at third amino acids insertion region. But, substitution of amino acids at L103R, L106K and L110R showed reduction in HR activity on tobacco suggesting their importance in activation of HR faster in the $HrpN_{Ep}$ although it requires further detailed analysis.