• Korean journal of applied entomology
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• v.48 no.3
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• pp.301-310
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• 2009

For the comparing of mortality of the resistance and susceptible population of Myzus persicae, etofenprox was treated in the recommended concentration of 200ppm. Mortalities of resistance population were 16.7 and 36.7%, and susceptible population were 86.7 and 86.7% after 24 and 48 hours treatment, respectively. For the detect of cross resistance to other pyrethroids, 6 pyrethroids were examined. Mortalities of susceptible and resistance populations were 90 and 31% to deltamethrin, 92 and 23% to lambda cyhalothrin, 81 and 14% to cypermethrin, 70 and 20% to $\alpha$-cypermethrin, 29 and 28% to fenpropathrin, 84 and 29% to fenvalerate, respectively. It was showed that resistance populations were generally resistive to other pyrethroids. On the other hands, for recognized ecological characteristic of M. persicae susceptible and resistance populations life table was tested on the pepper leaves in the petri dish and on the plant in the pot. This results were showed that intrinsic rate of increase ($r_m$), net reproduction number ($R_0$) and generation time in day ($T_c$) were significantly different between two population in both tested. However, life span and reproduction period were slightly different between them. Otherwise, feeding behaviors were tested using EPG technique with non- and treated etofenprox. First potential drop time of susceptible and resistance population was 73.5 and 257.9 sec with non-treated and 93.3 and 1076.2 sec after treated, respectively. Electrical probing signals were 8.2 and 48.8 times with susceptible and resistance individuals after treated etofenprox, respectively. It was supposed that the resistance is more probings than susceptible population. After treated, total feeding time have more 6,728.9 sec on resistance than 965.5 sec on susceptible population. So, total non penetration time of susceptible population was 3,000 sec longer than resistance population.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.440-446
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• 1986

The physiological reaction of two soybean (Glycine max (L.) Merrill) cultivars tolerant and susceptible to rust (Phakopsora pachyrhizi Syd.) was studied at the AVRDC in Taiwan, ROC. The rust epidemic on the susceptible cultivar began earlier and progressed more rapidly than on the tolerant cultivar. The defoliation by rust infection increased rapidly after the latter half of pod filling. The reduction of LA! by rust in the susceptible cultivar occurred earlier than in the tolerant cultivar. The differences in the chlorophyll content between the rust-free and rust-infected plants was 2.04% in the tolerant, and 16.43% in the susceptible cultivar. The shoot dry weight increased at each growth stage in the fungicide protected plots, but decreased in the non-fungicide protected plots after the R6 growth stage onward and the tendency to decrease was more severe in the susceptible than in the tolerant cultivar. The pod and seed dry weight of the suscep-tible cultivar in the fungicide-protected plot increased dramatically from the R6 growth stage, but in the non-fungicide plot, there was almost no increase in pod and seed dry weight from R6 growth stage, due to rust. The number of empty pods and imperfect grains were increased by rust infection, but the protein content was not afftected. There were reductions of oil content, seed length, seed width, seed thickness, pod thickness, number of pods and seeds, 100 seed weight, and yield due to rust infection. The yield losses by rust infection were 22.3%in the tolerant and 68.7% in the susceptible cultivar.

• Korean Journal of Weed Science
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• v.16 no.2
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• pp.150-159
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• 1996

This study was conducted to investigate the inhibition of protox activity and the PPIX accumulation of the oxyfluorfen-tolerant and-susceptible rice cultivars with barnyardgrass, a typical susceptible weed in accordance by oxyfluorfen treatment. The susceptible rice cultivars and barnyardgrass showed more inhibition of protox activity due to the treatment of oxyfluorfen than the tolerant rice cultivars. Especially in the concentration at $10^{-6}$M treatment, protox activity of the susceptible rice cultivars and barnyardgrass were the completely inhibited but the tolerant rice cultivars kept 32~59% of activity compared to the control. As the treatment concentration increased, the content of PPIX accumulation increased and it increased untill four hours of light exposure but it tended to decrease these after. The content of PPIX accumulation by the treatment of oxyfluorfen was more pronounced in the light condition than in the dark. Under the light and dark conditions, the susceptible rice cultivars and barnyardgrass showed more PPIX accumulation than the tolerant rice cultivate. Especialiy the susceptible barnyardgrass had more than the rice. With the treatment of GC and DA, tetrapyrrole biosynthesis inhibitor, the herbicidal activity by oxyfluorfen was inhibited, and the susceptible rice cultivars and barnyardgrass tended to have less effective than the tolerant rice cultivars and the content of chlorophyll or PPS accumulation tended to be similar.

• Korean Journal of Weed Science
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• v.16 no.1
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• pp.42-53
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• 1996

The tolerant and susceptible rice cultivars to oxyfluorfen were selected from 400 rice cultivars in a laboratory, and tested in comparison with barnyardgrass, a typical oxyfluorfen susceptible weed. The responses to oxyfluorfen in the different levels of calli, cells and protoplasts of the rice cultivars were investigated. $I_{50}$ value of the tolerant rice cultivars was about $10^{-4}M$, whereas that of the susceptible rice cultivars and barnyardgrass was about $10^{-6}M$, showing significant difference between the two groups. The growth rate of calli segregated from the tolerant rice cultivars was higher than that from the susceptible rice cultivars and barnyardgrass by treatment of oxyfluorfen to the calli. The growth rate of suspension-cultured cells of the tolerant rice cultivars was higher than that of the susceptible rice cultivars and barnyardgrass after treatment of oxyfluorfen. The viability of protoplasts from the tolerant rice cultivars was higher than that from the susceptible rice cultivars and barnyardgrass after one or two hours of oxyfluorfen treatment. The intactness of protoplasts from the tolerant rice cultivars was also higher than that form the susceptible rice cultivars and barnyardgrass.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.1
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• pp.7-11
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• 2007

The study was conducted on 162 adult male Haemonchus contortus of sheep collected from Avikanagar, Jaipur and Bikaner regions to diagnose the benzimidazole (BZ) resistance in H. contortus. The BZ resistance is primarily linked with the mutation in ${\beta}$-tubulin isotype 1 gene which substitute phenylalanine (Phe) into tyrosine (Tyr) at the 200 codon of the gene. An allele specific polymerase chain reaction (AS-PCR) technique was used for diagnosis of BZ resistance in H. contortus. In AS-PCR, one reverse primer (TGG 312) was used in two separate reactions with each of 2 forward primers (resistant TGG 331 and susceptible CAW 106 primer) that differed only at 3' nucleotide position. Therefore, the amplified products from resistant and susceptible parasites were produced 267 and 266 bp, respectively. A total of 162 parasites were genotyped, of which 130 parasites found homozygous resistant 'rr', 22 heterozygous 'rS' and 10 homozygous susceptible 'SS' type. The prevalence of 'rr' individuals was higher in Jaipur (98%) followed by Avikanagar (93%) and Bikaner (50%) regions. Overall, the prevalence of BZ resistant allele (r) was higher (87%) as compared to 13% of BZ susceptible allele (S).

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.6
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• pp.3483-3489
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• 2013

Background: To identify the prevalence of different stages of smoking and differences in associated risk factors. Materials and Methods: Thos longitudinal study started in February 2011 and the subjects were 2552 form one students aged between twelve to thirteen years of from 15 government secondary schools of Kinta, Perak. Data on demographic, parental, school and peer factors were collected using a self-administered questionnaire. We examined the effects of peer, school and parental factors on the five stages of smoking; never smokers, susceptible never smokers, experimenters, current smokers and ex-smokers, at baseline. Results: In the sample, 19.3% were susceptible never smokers, 5.5% were current smokers 6% were experimenters and 3.1% were ex-smokers. Gender, ethnicity, best friends' smoking status, high peer pressure, higher number of relatives who smoked and parental monitoring were found to be associated with smoking stages. Presence of parent-teen conflict was only associated with susceptible never smokers and experimenters whereas absence of home discussion on smoking hazards was associated with susceptible never smokers and current smokers. Conclusions: We identified variations in the factors associated with the different stages of smoking. Our results highlight that anti-smoking strategies should be tailored according to the different smoking stages.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.2
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• pp.119-127
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• 2013

The interaction between Agrobacterium and soybean has been studied at the transcriptome level but not at the metabolic level. However, it is necessary to investigate the difference in metabolites between susceptible and non-susceptible cultivars for high efficiency transformation. We investigated the difference in metabolites from sonicated soybean cotyledons of Korean cultivars and Bert cultivar. To identify difference in metabolites, sonicated extracts were analysed by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR/MS). The soybean cultivars were classified by susceptibility using green fluorescent protein expression. We found a difference in metabolites between the high susceptible and low susceptible cultivars. The FT-ICR/MS experimental m/z data of different metabolites were compared with theoretical m/z in KNApSAcK database. The candidate list was made using KNApSAcK and focused on phenolic compounds. These candidate metabolites are speculated to influence factors in the interaction. This list of candidates may be useful to investigate the interaction between Agrobacterium and plants to increase transformation efficiency.

• YAKHAK HOEJI
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• v.49 no.4
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• pp.312-316
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• 2005

To develop a new natural antibiotics from Koran plant resources for dealing with the current situation regarding the rapid increase in antibiotic-resistant pathogen, the in vitro inhibitory activities of essential oils from the young leaves of Glehnia littoralis (Umbelliferae) as well as its main constituents were evaluated against susceptible and resistant species of Streptococcus pneumoniae. The essential oil fraction of G. littoralis and its main components, $\alpha-and\;\beta-pinene$, exhibited significant inhibitory activities against the antibiotic-susceptible and resistant strains of S. pneumoniae, with MICs (minimum inhibiting concentrations) ranging from 4.0mg/ml to 16mg/ml. No remarkable differences were shown between the susceptible and resistant strains. Moreover, the disk diffusion test disclosed that these inhibitory activities were dose­dependent. Furthermore, data from the checkerboard titer test with FICIs (fractional inhibiting concentration indices) from 0.15 to 0.28 indicated synergisms between norfloxacin and $\alpha-or\;{\beta}-pinene$ in activity against S. pneumoniae KCCM49629 and S. pneumoniae CCARM4059.

• Plant Resources
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• v.5 no.3
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• pp.169-175
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• 2002

The soybean cyst nematode (Heterodera glycines Inchinoe; SCN) is a devastating pest of soybean and is responsible for significant losses in yield. The use of resistant cultivars is the effective method to reduce or eliminate SCN damage. The objective of this research is to identify AFLP markers linked to the SCN resistant genes. Bulked genomic DNA was made from resistant and susceptible genotypes to SCN and a total of 19 primer combinations were used. About 31 fragments were detected per primer combination. The banding patterns were readily distinguished in resistant and susceptible bulked genotypes. Polymorphic fragments were detected between resistant and susceptible bulked genotypes in the primer combination of CGT/GGC, CAG/GTG and CTC/GAG. In primer combinations of CGT/GGC and CAG/GTG, bulked resistant genotype produced a polymorphic bands. However, in primer of CTC/GAG, bulked susceptible genotype produced a polymorphic fragments. Three AFLP markers identified as a polymorphic fragments between bulked genomic DNA were mapped in 85 F2 population. Among them, only two markers, CGT/GGC and CTC/GAG, was linked and was mapped. Broad application of AFLP marker would be possible for improving resistant cultivars to SCN.

• Journal of the Korean Professional Engineers Association
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• v.10 no.3
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• pp.8-16
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• 1977

The pbjective of this study to clarify the varietal resistance to green leaf-and planthopper and the evaluate the nature of the resistance to the insects in connection with the Antibiosis. this study was investigated the reaction of the varieties to insects with 46 rice varieties including recommended varieties of korea, At seedling stage they were in fested with second of third inster nymphs. the results were as follows. 1. Most of the rice vari eties tested showed highly susceptible reaction to Brown planthopper except Mudgo, KR 108-143- and HR529-41-3-2 as resistance, and Akamoch, Satominori, IR 24 and IR 8 asmoderately suscptible. 2. In the test of varietal resistance to white backed planthopper Mudgo, KR 108-243-1, KR 109-154-2 and HR 529-45-3-2 were resistance, and Suweon 82, Tongil, IR 8 palkeum, Iri 309, Hokwang and Chuhoku #31 were Moderatly susceptible. 3. Most of the varieties tested were observed highly resistance to green leafhopper, but Tongil, Suweon 82, IR 24, Milsung and Chuhoku #31 were Moderatly susceptible. 4. the new bred lines HR 108-243-1 are multiple resistance of Brown planthopper, green leafhopper and white babked planthopper, and some others showed moderatly susceptible as. IR 8: Brown planthopper, white backed planthopper. IR 24: Brown poanthopper, green leafhopper. Tongil: suweon #82, Chukoku #31, whist backed planthopper, Green leafhopper.