• Korean journal of applied entomology
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• v.31 no.4
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• pp.536-542
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• 1992

Control effects of carbofuran soil incorporation just before transplanting on the early occur-ring rice insect pests were studied in the rice field. Also, its residual effects on the brown planthopper (BPH) were studied by pot experiments. Carbofurn soil incorporation in late May was much more effective in controlling the early occurring rice insect pests such as small brown planthopper, green leafhopper and rice stem borer than carbofuran broadcasting or diazinon (3G) + BPMC (50% EC) treatment in mid June. Residual effects of carbofuran soil incorportaion on the female adult BPH decreased ca. a half one month after treatment. However, its residual effects on the next generation of the BPH lasted much longer; control effects on the next generation were above 90 and 70% on 37 and 46 days after treatment, respectively. From these results, it is thought that carbofuran soil incorporation just before rice transplanting can be a good control method to the early occurring rice insect pests and the brown planthopper immigrating during June. Also, it can suppress immigrating BPH popula¬tion moderately in early July.

• The Plant Pathology Journal
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• v.35 no.1
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• pp.11-18
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• 2019

Gaeumannomyces graminis var. tritici is a soil borne pathogenic fungus associated with wheat roots. The accurate quantification of gene expression during the process of infection might be helpful to understand the pathogenic molecular mechanism. However, this method requires suitable reference genes for transcript normalization. In this study, nine candidate reference genes were chosen, and the specificity of the primers were investigated by melting curves of PCR products. The expression stability of these nine candidates was determined with three programs-geNorm, Norm Finder, and Best Keeper. $TUB{\beta}$ was identified as the most stable reference gene. Furthermore, the exopolygalacturonase gene (ExoPG) was selected to verify the reliability of $TUB{\beta}$ expression. The expression profile of ExoPG assessed using $TUB{\beta}$ agreed with the results of digital gene expression analysis by RNA-Seq. This study is the first systematic exploration of the optimal reference genes in the infection process of Gaeumannomyces graminis var. tritici.

• Korean journal of applied entomology
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• v.33 no.4
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• pp.270-280
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• 1994

This study was conducted to establish a nce insect pest control system, ~ es.ys tematic application of insecticides using carbohran and buproiezin, in Korea. The effects oi various dates of application and rates of buprofezin (25% WP) after carbofuran (3G) soil incorpombon in late May on the pop~~lation densities of the brown planthoppa (BPH) immigrating in July were investigated Appropriate application tune of buprofezin for the BPH that had evaded insecticidal effect of 5011 incorporated carbofuran was late July-early August. Application rate of buprofezln at 7.0g a.i/lOa was enough to suppress the BPH density. Buprofezin treatment after carbofumn soil incorporation could also suppress the whlte backed planthopper population but did not affect the densities oi the paddy rice spiders. Considering the charactenstics of occurring patterns of the nce insect pests in Korea. buprofezin treatment m late July or early August after carbofuran soil incorporation in late May can be a useful application system of ir~sectic~deins controlling early season Insect pests and migmtoly planthoppers on rice.

• Asian Journal of Turfgrass Science
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• v.11 no.3
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• pp.185-191
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• 1997

Biological control of turfgrass insect pest Blitopertha orientalis, forest insect pests, Agelastica coerulea, Meganola melancholia, and Glyphodes perspectalis,vegetable insect pests, Plutella xylostella and Agrotis segetum were conducted with entonopathogenic fungus, Metarhizium anisopliae J-22 isolated from black pine forest soil in Cheju province. Mortality of B. orientalis larvae was 53.3% at the rate of 3.4 $\times$ 1O 7 conidia /ml. A. coerulea and M melancholia larvae showed 100% mortalities at 9.6 $\times$ 106 conidia /ml and 2.7 $\times$ 10 7 conidia /ml as well. However, G. perspectalis larvae were not dead even at 4$\times$ 1O 7 conidia /ml. On the other hand, M anisopliae J-22 was effective against P. xylostella larvae showing 100% mortality at 4 $\times$ 10 7 conidia /ml. KEy words:Entomopathogenic fungi, Biological control, Metarhizium anisopliae, Pathogenicity,Blitopertha orientalis, Agelastica coerulea, Meganola melancholia, Glyphodes perspectalis,Plutella xylostella, Agrotis segetum.

• The Plant Pathology Journal
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• v.25 no.1
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• pp.70-76
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• 2009

The rhizobacteria of Panax notoginseng were isolated from six sites in Yanshan, Maguan and Wenshan Counties, Yunnan Province of China, and their antagonistic activity against P. notoginseng root-rot fungal pathogens was determined. Of the 574 rhizobacteria isolated, 5.8% isolates were antagonistic in vitro to at least one of the five pathogens, Cylindrocarpon didynum, Fusarium solani, Phytophthora cactorum, Phoma herbarum, and Rhizoctonia solani. The number of rhizo bacteria and the number that inhibited fungi differed depending on sampling sites and isolation methods. Rhizobacteria isolated from the site in Yanshan and Maguan showed more antagonistic effect than them in Wenshan. Heat treatment of rhizosphere soil at $80^{\circ}C$ for 20 min scaled the antagonists up to 14.0%. Antagonistic bacteria in the roots proportioned 3.9% of the total isolates. The most antagonistic isolates 79-9 and 81-4 are Bacillus subtilis based on their 168 rDNA sequence and biochemical and physiological characteristics. Identification and evaluation of antagonistic bacteria against P. notoginseng root-rot pathogens in the main planting areas improved our understanding of their distribution in rhizosphere soil. Furthermore these results indicated that the interactions between biocontrol agent and soil microbes should be seriously considered for the successful survival and biocontrol efficacy of the agents in soil.

• The Korean Journal of Soil Zoology
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• v.2 no.2
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• pp.76-82
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• 1997

Mortality of some agro-forest insect pests, Agrotis segetum, Blitopertha orientalis, Agerastica coerulea, Glyphodes perspectalis and Acantholyda parki caused by entomopathogenic nematodes was investigated in laboratory and in pot. Steinernema carpocapsae All and Pocheon strain were effective against 2nd of 3rd instar larvae of A. segetum showing 100% mortalities at the concentration of 10Ijs/larva but not effective against 4th inster larvae. Mortality of B. orientalis was 100% after 26 days in H. bacteriopora NC 1, H. bacteriophora Hamyang and S. glageri NC strain treatment. S. monticulum also showed 100% mortalities against A. coerulea andd G. perspectalis at the concentration of 80 and 40 Ijs/larva. However, H. bacteriophora Cheju and S. glaseri Cheju strain were not effective against A. parki, i.e., showing 23.3 and 20.0% mortalities, respectively at the concentration of 160Ijs/larva. S. glaseri Hanrim strain was more effective than H. bacteriophora Cheju strain against Pryeria sinica.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.2
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• pp.77-85
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• 2006

Entomopathogenic nematodes (EPNs) have been used as biological control agents for control of various agro-forest insect pests, and are especially effective against soil-dwelling insect pests. Effect of soil moisture on pathogenicity of commercial EPNs for white grub control was evaluated in laboratory, pots, and golf courses. Pathogenicity of EPNs in sand column was variable depending on depth, soil moisture, and EPN species or strain. All tested EPNs (Heterorhabditis sp. GSNUH1, Heterorhabditis sp. GSNUH2, Steinernema carpocapsae GSN1, and S. longicaudum Nonsan strain) showed similar pathogenicity against the bait insect, great wax moth (Galleria mellonella) larva at 2 cm deep at a given soil moisture. However, pathogenicity of the Heterorhabditis sp. GSNUH1 strain was decreased with increasing soil moisture. Pathogenicity of S. carpocapsae GSN1 strain was the lowest in 3% soil moisture (v/w) at 7 cm depth. However, there was no difference in pathogenicity between Heterorhabditis sp. GSNUH2 and S. longicaudum Nonsan strain. Although pathogenicity of Heterorhabditis sp. KCTC 0991BP strain showed no difference against the 2nd instar of Exomala orientalis, that of the S. carpocapsae GSN1 strain was decreased in the laboratory depending on soil moisture. Highly pathogenic strain EPN, Heterorhabditis sp. KCTC 0991BP strain, showed higher pathogenicity at 100 mm irrigation than non-irrigation or 10 mm irrigation. However, poor pathogenic strain EPN, S. carpocapsae GSN1 strain, was not different in pathogenicity from the 2nd instar of Exomala orientalis in creeping bentgrass (Agrostis palustris) depending on irrigation amount in the pot. Pathogenicity of EPNs in field experiment at the tee of Ulsan golf club showed a similar trend to that in the pot experiment.

• Journal of Wetlands Research
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• v.14 no.4
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• pp.687-698
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• 2012

This study was conducted to monitor and prevent outbreak of insect pestsin dredged soil dumping area after completion of dredging construction in Masan City. Monitoring was carried out using tent trap, colored sticky trap, and CDC light trap. A total of 217,073 individuals belonging to 23 species from 10 families in 3 orders were collected. In overwintering survey using tent trap, 3 species were collected. 2 species (Leptocera fuscipennis (Haliday) and Ephydra japonica Miyagi) of them were outbreak species. In color sticky trap, more than 96% of total individuals were comprised of five species: Urolepis maritima Walker (43%), E. japonica (19%), Fucellia sp. 1 (13%), Philotelma sp. 1 (10%), and Homalometopus sp. 1 (9%). In CDC light trap, three dominant species were Homalometopus sp. 1 (91%), Glyptotendipes tokunagai Sasa (6%), and L. fuscipennis (1%), representing about 98% of the total. To prevent damage caused by outbreak of insect pests, we carried out ecological control methods such as covering the fresh soil in outbreak area, using light trap, pumping up water and so on, minimizing use of thermal fogging and insect growth regulatorwhen the insect pest population was rapidly increasing.

• Journal of Korean Society of Forest Science
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• v.96 no.5
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• pp.585-590
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• 2007

Rhizina undulata is the fungus, which causes Rhizina root rot on coniferous trees. Nested-PCR using ITS-specific primer was applied to detect R. undulata from the soils of Japanese black pine (Pinus thunbergil) forests infested with the disease in Seocheon, Chungnam Province, South Korea. Soil samples were collected from four different sites, both dead trees and fruit bodies of R. undulata were present, dead trees only present, fruit bodies only present, and both were absent. Nested-PCR products specific to R. undulata ITS-region were amplified. Positive reactions were found in some samples from the sites, where dead trees and fruit bodies of R. undulata were absent as well as where both of those were present. R. undulata was mainly detected in the soil samples from the depth of 5~20 cm under the soil surface. These results show that the nested-PCR could be used to diagnose the presence or potential infestation of R. undulata in the soils of pine forests.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.4
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• pp.490-497
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• 2010

A chitinolytic bacterium having a strong antagonistic activity against various pathogens including Phytophtora capsici was isolated from rhizosphere soil, and identified as Lysobacter enzymogenes (named as LE429) based on 16S rRNA gene sequence analysis. This strain produced a number of substances such as chitinase, ${\beta}-1$, 3-glucanase, lipase, protease, gelatinase and an antibiotic compound. This antibiotic compound was purified by diaion HP-20, sephadex LH-20 column chromatography and HPLC. The purified compound was identified as phenylacetic acid by gas chromatography-electron ionization (GC-EI) and gas chromatography-chemical ionization (GC-CI) mass spectrometry. In field experiment, pepper plants were treated by the strain LE429 culture (CB), neem oil solution (NO), combination (CB+NO) or control (CON). Plant height and number of branches, flowers and pods of pepper plant in CB treatment were generally highest, and followed by CB+NO, CON and NO. The fungal pathogens were strongly inhibited, while several insect pests were discovered in CB treatment. Any insect pests were not found, while all fungal pathogens tested were not suppressed in NO treatment. However, in CB+NO treatment, non incidence of fungal pathogens and insect pests were found. The strain LE429 producing secondary metabolites with neem oil should be a potential agent to control fungal diseases and insect pests.