• Korean journal of applied entomology
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• v.49 no.4
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• pp.385-391
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• 2010

This study reports the results of natural enemy application against four insect pests on greenhouse sweet pepper in winter cropping system. Orius laevigatus ($3.3/m^2$) was released at two different times (Nov. 2005 & Feb. 2006) to control Frankliniella occidentalis, western flower thrips (WFT). Throughout the cropping season, the lowest level recorded of WFT was less than 2.0 individuals per yellow sticky trap. Amblyseius swirskii ($232.3/m^2$) was released four times (Nov. 2007 ~ Aug. 2008) to control Bemisia tabaci, tobacco whitefly (TWF). Until July 2008, TWF population had been suppressed lower than 6.6/trap. Phytoseiulus persimilis ($44.5/m^2$) was released seven times (Apr. 2008 ~ Aug. 2008) to control Tetranychus kanzawai, tea red spider mite (TRSM). As a result, TRSM population was suppressed lower than 1.7/1eaf. To control aphids, Aphidius colemani ($9.5/m^2$) was released seven times (Oct. 2004 ~ Jan. 2005), with the transplantation of banker plants ($5.5pot/660m^2$). As a whole, aphid's population has been successfully reduced to less than 2.0/leaf.

• Korean Journal of Agricultural Science
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• v.26 no.2
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• pp.13-18
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• 1999

External morphology characteristics of the greenhouse whitefly, Trialeurodes vaporarium were investigated by scanning electron microscopy. The antennae of the greenhouse whitefly was 6 segments. rod-shape, and 0.3mm length. On the 6th segment, there were many sensilla for searching host-plant as olfactory receptor. The mouthpart of the greenhouse whitefly was a piercing-sucing type, then its stylet was well developed for piercing plant leaf tissue. Claw of the foreleg was a 3-way hook shape including paranychium for attaching plant surface to pierce and lay egg.

• Korean Journal of Plant Tissue Culture
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• v.25 no.3
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• pp.147-152
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• 1998

AL1-gene, necessary for the replication of the genome of a gemini virus TGMV, was inserted in the opposite direction to the promoter CaMV35S resulting in the construction of a plant transformation binary vector pAR35-2. The vector pAR35-2 contains the chimeric gene cassette involving the duplicated promoter CaMV35S, opposite direction of AL1-gene fusioned with hygromycin resistant gene, and the gene cassette of the neomycin phosphotransferase II gene. The plasmid was transferred to tobacco and tomato plants by leaf disk infection via Agrobacterium. The transgenic plants were selected and grown on the MS-agar medium containing kanamycin and hygromycin. The shoots induced from the calli were regenerated to the whole transgenic plants. The antisense AL1-gene was detected in the genomic DNA isolated from the leaves by using the PCR mediated Southern blot analysis. The expression of the antisense AL1-gene was also observed using the RT-PCR mediated Southern blot analysis. The observation of chloroplasts in guard cell pair indicated that the transgenic tomato plants were diploid.

• Korean Journal of Plant Tissue Culture
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• v.28 no.2
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• pp.69-74
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• 2001

Calli were induced on MS medium supplemented with 0.5 mg/L 2,4-D by using the leaf explants of haploid which were derived from the diploid and haploid of Nicotiana tabacum cv BY4. These calli were subcultured on MS medium with the combination of 2.0 mg/L 2,4-D, 1.0 mg/L kinetin and 0.1 mg/L BAP. Cell propagation of diploid plants were good in a combination of 2.0 mg/L 2,4-D, 0.1mg/L BAP in vitro conditions, suspension cultures were conducted in equal condition. Homogenized suspension cultured cells were smeared 2.0 mL each on MS medium with 0~100 $\mu$M PFP, to select the resistant colony to PFP, and were examined after 10d, 20d and 30d. Measurment of fresh weight of cells after 30d of culture shows that with more concentration of PFP in medium the fresh weight of the cells decreased. In case of diploid, selected callus was the highest in vitro treated with 5 $\mu$M PFP. It was higher than control until 100 $\mu$M PFP. The active degree of catalase was the highest in vitro with 5 $\mu$M PFP but the lowest in vitro with 10 $\mu$M PFP on the other hand, in case of haploid plant, the active degree of peroxidase and catalase was the highest in vitro treated with 50 $\mu$M PFP. It's sure that enzyme active degree of between diploid and haploid had big differences.

• The Korean Journal of Pesticide Science
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• v.8 no.4
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• pp.338-346
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• 2004

The methanol extract of Chloranthus japonicus roots effectively controlled the development of rice blast(Magnaporthe grisea), rice sheath blight(Corticium sasaki), tomato pay mold(Btrytis cinerea), tomato late blight(Phytophthora infestans), and wheat leaf rust(Puccinia recondita). From the methanol extract of C. japonicus roots, three antifungal substances were isolated. Their chemical structures were determined to be shizukanols B, C, and D mainly by mass and NMR spectral data. Among the three substances, shizukanol C showed the strongest inhibitory activity against mycelial growth of the plant pathogenic fungi tested; it completely inhibited mycelial growth of M. grisea. Colletotrichum gloeosporioides, and C. acutatum at concentrations of more than $12.5{\mu}g$/ and P. infestans at concentrations of more than $3.13{\mu}g/m\ell$. They also controlled effectively the development of rice blast and wheat leaf rust. On the other hand, they caused phytotoxic symptoms on barley leaves and inhibited the growth of duckweed (Lemna paucicostata) with $EC_{50}$ values of $30.0{\mu}g/m\ell$ for shizukanol B, $49.9{\mu}g/m\ell$ for shizukanol C, and $154{\mu}g/m\ell$ for shizukanol D. In addition, shizukanol C showed an insecticidal activity against brown planthopper (Nilaparavata lugens), peen peach aphid (Myzus persicae), diamond-back moth (Plutella xylostella), and tobacco cutworm (Spodoptera litura) of the 5 arthropod pests tested with mortality values of more than 60% at a concentration of $1,000{\mu}g/m\ell$.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.407-414
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• 2010

Bacillus subtilis strains isolated from different regions of Korea were screened for their plant growth promotion and induced systemic resistance (ISR) in tomato and red-pepper. The plant growth promotion on red-pepper and tomato revealed maximum plant height (22.73 cm) on red pepper treated with B. subtilis strain JE 21-1 and 30.18cm in case of tomato treated with B. subtilis strain JE 8-1. There was also significant improvement in root and shoot dry weight in both the plants. The strain JE 21-1 showed better promise for all growth parameters in red-pepper and tomato when compared to other strains and positive check BTH. Different strains screened in square plate method also revealed maximum plant height and leaf width, and suppressed anthracnose on red pepper in case of strain JE 21-1 at $10^6$ and $10^7$ cells/ml when compared to other strains. In all the bacterial inoculations the population was significantly high when compared to untreated check. In plant growth promotion with respect to fruit length and weight, fruit length was maximal in treating with JE 9-4 and ES 2-2, while fruit weight was maximal in treating with JE 3-6, ES4-2, ES2-2 and JE 21-2 on red pepper. In case of tomato, comparatively better fruit weight was in JE 21-1, ES 3-3 and JE 10-2 when compared to BTH and untreated control. The soft rot disease caused by Pectobacterium carotovorum SCCI was completely suppressed in case of transgenic tobacco harboring GUS gene related to PR1a and increased the level of salicylic acid significantly in combined application of JE 9-4 on par with BTH. Thus, this study clarified some potential Bacillus subtilis strains for plant growth promotion and ISR in red-pepper and tomato.

• Korean Journal of Weed Science
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• v.18 no.3
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• pp.205-213
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• 1998

This experiment was carried out to produce herbicide resistant potatoes hawing only chimeric phosphinothricin acetyltransferase (PAT) genes without using antibiotic selectable marker. The pDY502 vector having only PAT gene was reconstructed for transformation of potato. The reconstructed vector was introduced to Agrobacterium tumefaciens MP90 disarmed, and they were used for potato transformation. Hormonal requirement for plant regeneration from leaves and stem explants of potato was investigated. From this experiment, MS medium treated with IBA 0.1 mg/L + BA 0.5 mg/L was the best for potato regeneration, and the ratio of shoot regeneration was 54% for leaf and 46% for stem in that condition. For transformation, explants of potato leaves and stems were cocultured with A. tumefaciens MP90 containing reconstructed vector harvoring only PAT gene. When the potato explants were placed on various concentrations of bialaphos and all the potato explants were dead on medium with over 5.0mg/L bialaphos. By this selection methods, the explants cocultured with Agrobacterium produced the putative transgenic shoots on medium with 5mg/L bialaphos treatment after 3-4 weeks. Second selection was performed by transferring the shoot tips of putative transgenic to medium containing 20mg/L of bialaphos. The shoot tips grew well on the second selection medium, indicating the production of successful transgenic plants. But normal shoots were dead in same cytotoxic medium. Incorporation of the PAT gene into transgenic potatos were confirmed by PCR analysis of DNA and Southern hybridization. These results show that the PAT gene can serve as a selectable marker and herbicide resistant genes for transformation of potato.

• Korean journal of applied entomology
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• v.24 no.4 s.65
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• pp.223-230
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• 1986

A series of experiments were carried out to evaluate the differences in susceptibility of the 13-aphidicidial insecticides in the green peach aphids(Myzus persicae) collected from 13 different localities. The aphids were reared and increased on the potted tobacco plants in the laboratory. The susceptibility to insecticides was compared at the $LC_{50}$ levels with the resistant ratio by a leaf-dip method with a laboratory strain reared for 2 years in the laboratory without exposure to insecticides. The susceptibility to the insecticides was greatly varied with the local strains. The local strains demonstrated relatively high resistance to the insecticides over the laboratory strain at the $LC_{50}$ level; in resistant fold, 2.3 to 519.0 to cypermenthrin, 2.3 to 494.5 to decamethrin, 2.8 to 442.4 to fenvalerate, 2.5 to 170.6 to formothion, 1.5 to 494.5 to decamethrin, 2.8 to 442.4 to fenvalerate, 2.5 to 170.6 to formothion, 1.5 to 231.8 to phosphamidon, 3.1 to 42.1 to monocrotophos, 1.0 to 30.9 to phenthoate+dimethoate, 1.8 to 21.0 to heptanophos, 2.1 to 24.8 to oxydemeton-methyl, 1.0 to 24.9 to thiometon, 1.6 to 4.7 acephate, 0.8 to 4.1 to pirimicarb.