• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.4
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• pp.281-285
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• 2005

Pod dehiscence (PD), defined as the opening of pods along both the dorsal and ventral sutures, causes the seed to shatter in the field before harvesting and results in loss of seed yields. However, breeding for resistance to PD is difficult due to the complicated genetic behavior and environmental interaction. The objective of the present research was to analyze the genetic behavior of PD for improving the breeding efficiency of resistance to PD in soybean. PD after oven-drying the sampled pod at $40^{\circ}C$ for 24 hours was the most reliable to predict the degree of PD tested in the field. Keunolkong, a dehiscent parent, was crossed with non-dehiscent parents, Sinpaldalkong and Iksan 10. Using their $F_1\;and\;F_2$ seeds, PD was measured after oven drying the pod at $40^{\circ}C$ for 24 hours. The gene conferring PD behaved in different manners depending on the genetic populations. In the Keunolkong$\times$Sinpaldalkong population, PD seemed to be governed by single major recessive gene and minor genes, while several genes were probably involved in the resistance to pod dehiscence in the Keunolkong$\times$Iksan 10 population. Heritability for PD estimated in F2 population showed over $90\%$ in the two populations. High heritability of PD indicated that selection for resistance to PD should be effective in a breeding program. In addition, genetic mapping of quantitative locus (QTL) for PD in both populations may reveal that genes conferring PD are population-specific.

• Journal of the Korean Society of Tobacco Science
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• v.28 no.2
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• pp.100-110
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• 2006

A mutant of Potato vims Y (PVY) was occurred in PVY resistance flue-cured tobacco breeding line KF0402 $(TC1146{\times}KF117)$ showing vein necrosis at Suwon in Korea. This isolate, PVY-SWM, was differentiated from other PVY based on biological properties and nucleotide sequence analyses of coat protein gene. PVY-SWM caused typical symptoms on 21 indicator plants as compared to the PVY-TOJC37. Remarkably, the PVY-SWM induced distinctly different symptom of systemic vein necrosis on tobacco cultivars V.SCR, PBD6, TN86, TN90, Virgin A Mutant (VAM), Wislica, NC744, KB108 and KB111, which were reported to have the recessive potyvirus resistance gene va. In RT-PCR assays with specific primers for detection of PVY, a single band of about 800bp in length was produced. The amplified DNA was cloned and the nucleotide sequence was determined. The coat protein gene of PVY-SWM showed 88.4%-99.0% and 92.5%-98.5% identities to the 12 different PVY isolates of Genbank Database at the nucleotide and amino acidi respectively. Multiple alignments as well as cluster dendrograms of PVY-SWM isolate revealed close phylogenetic relationship to the $PVY^{NTN}$ subgroup.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.4
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• pp.296-302
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• 2001

Winter cereals are acclimated during wintering, and thereafter their freezing resistance is increased. In order to analyze inheritance and heritabilities for photoinhibition of photosynthesis by high light intensity under low temperature, and to evaluate the relationship between low temperature-induced photoinhibition and winter survival, 4 parental half diallel crosses were used. The detached leaves of 7-8cm long from plants grown for 35 and 55 days were placed on wet filter paper and placed in trays at 5$^{\circ}C$ cold room with 1,200 $\mu$mol $m^{-2}$ $s^{-1}$ PPFD. Chlorophyll fluorescence was measured with a chlorophyll fluorescence system after dark adaptation for 30 min. The Fv/Fm of 35day old plants was reduced from 0.714 in the control leaves to 0.409 and 0.368 following photoinhibitory treatment of 6h and 8h and the CVs were increased from 0.8% to 22.2-22.3%. The Fv/Fm of 55-day old plants was reduced from 0.775 in the control leaves to 0.485 and 0.439 following photoinhibitory treatment of 10h and 12h, respectively. According to half diallel cross analysis, Reno and Dongbori 1 (highly resistant to photoinhibition) was dominant, but Oweolbori (susceptible to photoinhibition) was recessive, and photoinhibition showed partial dominance with highly additive gene action. Dongbori 1 showed the greatest GCA effects for photoinhibition, and GCA/SCA ratios (8.7-22.3 times) indicated that the additive variance for the character was more important. Winter survival in barley crosses was positively correlated with resistance to photoinhibition and significantly fitted by linear regression ($R^2$=0.751$^{**}$-0.779$^{**}$). The chlorophyll fluorescence measured by Fv/Fm has been found to be highly inheritable and very useful in evaluating relative levels of freezing resistance in barley.ley.

• Korean journal of applied entomology
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• v.43 no.1
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• pp.43-48
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• 2004

Development of 3,700 folds resistance to etoxazole was found in the population of twospotted spider mite, Tetranychus urticae, collected from rose greenhouses in Buyo, Chungnam Provience in August 2000. This population was selected for 3yr with etoxazole to get 5,000,000 folds increase in resistance as compared to susceptible (S) strain. The etoxazole resistance was stablized for 16 months under the condition of no acaricide application. Inheritance and cross resistance in etoxazole to some acaricides of the etoxazole resistance strain (R) were investigated. There were differences of susceptibility in the etoxazole concentration-mortality relationships between $F_1$, $F_2$ progenies obtained from reciprocal cross with the S and R strains (R$_{♂}$${\times}$S$_{♂}$${\times}$R$_{♂}$). Degrees of dominance were 0.98 and 0.98 in $F_1$ and $F_2$ progenies of R$_{♂}$${\times}$S$_{♂}$, and -0.97 and -0.68 in $F_1$ and $F_2$ progenies of S$_{♀}$${\times}$R$_{♂}$ respectively. Inheritance in $F_1$ and $F_2$ progenies of R$_{♀}$${\times}$S$_{♂}$ were complete dominant. However $F_1$ and $F_2$ progenies of S$_{♀}$${\times}$R$_{♂}$ were incomplete recessive. These results suggest that inheritance of etoxazole resistance is controlled by a complete dominance. The R strain exhibited cross resistance to acequinocyl and emamectin benzoates in adult females, and milbemectin, amitraz and pyridaben in eggs. However they showed negatively correlated cross-resistance to bifenazate, a carbazate acaricide. These results may indicate bifenazate could be useful for the control of etoxazole resistant T. urticae population.

• Korean journal of applied entomology
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• v.44 no.2
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• pp.151-156
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• 2005

The development of resistance to bifenazate (resistance ratio of egg=40.3 folds) was found in population of the twospotted spider mite, Tetranychus urticae, collected from rose greenhouses in Chilgok, Gyeongbuk Province in December 2000. This population was selected for 4 years with bifenazate treatment (over 150 times), and showed 248.8 folds increase in resistance as compared to susceptible (S) strain. Inheritance of bifenazate resistant strain (R) and cross resistance of this strain to 9 acaricides were investigated. There were differences of susceptibility in the bifenazate concentration-mortality relationships in F1 progenies obtained from reciprocal cross with the S and R strain $(R{\times}S,\;S{\times}R)$. Degrees of dominance were 0.48 and 0.94 in adult females and eggs of $R{\times}S$ and -0.85 and -0.17 in adult females and eggs of $S{\times}R$, respectively. Inheritance type in the F1 progeny of $R{\times}S$ was incomplete dominant, and F1 progeny of $S{\times}R$ was incomplete recessive. These results suggest that inheritance of bifenazate resistance is controlled by a complete dominance. The R strain exhibited cross resistance to acequinocyl and fenpyroximate in adult females, and amitraz, emamectin benzoate, fenpyroximate, milbemectin, pyridaben and spirodiclofen in eggs. However they showed negatively correlated cross-resistance to emamectin benzoate and milbemectin in adult females, and abamectin in eggs.

• Proceedings of the Botanical Society of Korea Conference
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• 1994.09a
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• pp.29-39
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• 1994

Serious issues about the changes in the environmental conditions on earth associated with human activities have arisen, and the interest in these problems has increased. It is urgent to determine how the expansion of terrestrial UV-B radiation due to the stratospheric ozone depletion influences living matters. In this connection, we have been investigating the effects of UV-B radiation on the growth of rice cultivars (Oryza sativa L.). We report here some physiological and genetic aspects of resistance to inhibitory effects of UV-B radiation on growth of rice cultivars as described below. Elevated UV radiation containing large amount of UV-B and a small amount of UV-C inhibited the development of plant height, the photosynthetic rate and the chlorophyll content in rice plants in a phytotron. Similar results were obtained in experiments, in which elevated UV-V radiation. Similar results were obtained in experiments, in which elevated UV-B radiation (transmission down to 290 nm) was applied instead of UV-B radiation containing a small amount of UV-C. The inhibitory effects of UV radiation was alleviated by the elevated CO2 atmospheric environment or by the exposure to the high irradiance visible radiation. The latter suggested the possibility that the resistance to the effects of UV radiation was either due to a lower sensitivity to UV radiation or to a greater ability to recover from the injury caused by UV radiation through the exposure to visible radiation. The examination of cultivar differences in the resistance to UV radiation-caused injuries among 198 rice cultivars belonging to 5 Asian rice ecotypes (aus, aman, boro, bulu and tjeleh) from the Bengal region and Indonesia and to Japanese lowland and upland rice groups showed the following: Various cultivars having different sensitivities to the effects of UV radiation were involved in the same ecotype and the same group, and that the Japanese lowland rice group and the boro ecotype were more resistant. Among Japanese lowland rice cultivars, Sasanishiki (one of the leading varieties in Japan) exhibited more resistance to UV rakiation, while Norin 1 showed less resistance, although these two cultivars are closely related. It was thus indicated that the resistance to the inhibitory effects of UV radiation of rice cultivars is not simply due to the difference in the geographical situation where rice cultuvars are cultivated. Form the genetic analysis of resistance to the inhibitory effects of UV radiation on growth of rice using F2 plants generated by reciprocally crossing Sasanishiki and Norin 1 and F3 lines generated by self-fertilizing F2 plants, it was evident that the resistance to the inhibitory of elebated UV radiation in these rice plants was controlled by recessive polygenes.

• Korean Journal Plant Pathology
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• v.1 no.2
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• pp.136-140
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• 1985

The studies were conducted to test for combining ability and to evaluate resistance to maize dwarf mosaic virus (MDMV) by diallel crosses of corn inbreds. For the genetic analysis of the resistance, a diallel set of crosses without reciprocals was made using the eight corn inbreds which had different degrees of resistance to MDMV. Twenty eight $F_1$ hybrids showed different symtom severity. the highest value is 3.63 and the lowest value is 1.87 in disease ratings (1-4). General combining ability (GCA) for resistance to MDMV was highly significant, but specific combining ability (SCA) was not significant. Two inbreds, A632 and KS15 showed negative GCA effects, indicating that these parents were good general combiners and that resistance to MDMV increased in hybrid combinations. Hyrid A632 x KS5, showed the highest negative SCA effect and several combinations showed negative SCA effects. The analysis of parent-offspring covariance (Wr) and array variance (Vr), suggest that there may be many dominant genes in the resistant inbreds and many recessive genes in the susceptible inbreds.

• Korean Journal of Agricultural Science
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• v.4 no.2
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• pp.191-198
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• 1977

This study was conducted to determine the inheritance to bacterial leaf blight in rice. Varieties used in the study were IR1544-349-2, IR1698-237-2, IR1529-680-3, IR28, IR29, RP663-337-7-8-4-1-1, RP291-20, 62-595 and Kele. The isolate of bacteial leaf blight used was 71-23, 76-1 of Xanthomonas oryzae. $F_1s$ were obtained from crosses between resistant and susceptible varieties. Field observation was made from the Parents, $F_1s$ and $F_2$ sagregating population. The result is summaryzed as fallow: 1) The resistance to the bacterial leaf blight (71-23) derived from cultivars IR1529-680-3, IR28, IR29, RP663-337-7-8-4-1-1, RP291-20 and 62-595 was controlled by a single dominant gene. 2) The resistance to the bacterial leaf blight (71-23) derived from cultivars IR1545-339-2, IR1544-340, IR1698-237-2 and Kele was controlled by a single recessive gene. 3) The resistance to the bacterial leaf blight (76-1) derived from cultivars IR1545-339-2, IR1544-340, IR 1698-237-2 was controlled by a single dominant gene. 4) Degree of resistance to the bacterial leaf blight and genetic type were different depending on isolates within the same resistant cultivar. 5) There was no relation between resistance to the bacterial leaf blight and heading days.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.712-721
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• 1997

The objectives of this study were; (1) to identify and localize QTLs for resistance to soybean cyst nematode(SCN) race 5 on RAPD map, (2) to idntify the magnitude and mode of inheritance for each QTL, and (3) to identify the best combinations of QTLs for resistance to SCN race 5. Based on the univariate regression analysis, we detected 26 markers(22 RAPD and 4 RFLP) which showed significant association(P<0.05) with resistance to SCN race 5. From MAPMAKER /QTL analysis, we identified two regions (LGC-20 and Group 2) for resistance to SCN race 5. The QTL that was localized at 8.0 cM from pK418C on LGC-20 showed a recessive mode of inheritance and the QTL that was localized between W03 and E02$^3$ on Group 2 showed a dominant mode of inheritance. Two pairs of flanking markers (E02$^3$ and W03, pK418C and pK418E$_1$) and one unlinked RAPD marker, G10$^1$ were used for multiple regression analysis. Marker combination which was composed of 4 markers, E02$^3$, G10$^1$, W03, and pK418E$_1$, explained the highest amount of phenotypic variation by SCN (35.2％). Further research for the identification of QTLs for resistance to SCN race 5 to explain larger portion of phenotypic variation is needed.

• Childhood Kidney Diseases
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• v.24 no.1
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• pp.58-61
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• 2020

Pseudohypoaldosteronism type 1 (PHA1) is a rare salt-wasting disorder caused by resistance to mineralocorticoid action. PHA1 is of two types with different levels of disease severity and phenotype as follows: systemic type with an autosomal recessive inheritance (caused by mutations of the epithelial sodium channel) and renal type with an autosomal dominant inheritance (caused by mutations in the mineralocorticoid receptor). The clinical manifestations of PHA1 vary widely; however, PHA1 commonly involves hyponatremia, hyperkalemia, metabolic acidosis and elevated levels of renin and aldosterone. The earliest signs of both type of PAH1 also comprise insufficiency weight gain due to chronic dehydration and failure to thrive during infancy. Here, we report a case of renal PAH1 in a 28-day-old male infant harboring a novel heterozygous mutation in NR3C2 gene (c.1341_1345dupAAACC in exon 2), showing only failure to thrive without the characteristic of dehydration.