• Molecules and Cells
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• v.25 no.2
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• pp.205-210
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• 2008

To develop molecular markers linked to the $L^4$ locus conferring resistance to tobamovirus pathotypes in pepper plants, we performed AFLP with 512 primer combinations for susceptible (S pool) and resistant (R pool) DNA bulks against pathotype 1.2 of pepper mild mottle virus. Each bulk was made by pooling the DNA of five homozygous individuals from a T10 population, which was a near-isogenic $BC_4F_2$ generation for the $L^4$ locus. A total of 19 primer pairs produced scorable bands in the R pool. Further screening with these primer pairs was done on DNA bulks from T102, a $BC_{10}F_2$ derived from T10 by back crossing. Three AFLP markers were finally selected and designated L4-a, L4-b and L4-c. L4-a and L4-c each underwent one recombination event, whereas no recombination for L4-b was seen in 20 individuals of each DNA bulk. Linkage analysis of these markers in 112 $F_2$ T102 individuals showed that they were each within 2.5 cM of the $L^4$ locus. L4-b was successfully converted into a simple 340-bp SCAR marker, designated L4SC340, which mapped 1.8 cM from the $L^4$ locus in T102 and 0.9 cM in another $BC_{10}F_2$ population, T101. We believe that this newly characterized marker will improve selection of tobamovirus resistance in pepper plants by reducing breeding cost and time.

• Journal of Forest and Environmental Science
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• v.31 no.3
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• pp.164-176
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• 2015

Cyathea gigantea is a tree fern distributed throughout humid tropical regions of northeast India and other parts of the country. However, wild populations of this species are largely affected by various natural and anthropogenic activities. Therefore, an attempt was made to study the population structure and regeneration status of C. gigantea in and around greater Itanagar area of Papum Pare district, Arunachal Pradesh. Altogether 45 patches, ranging from 19.63 to $260m^2$ of area, were randomly sampled to study population structure and regeneration status of the species. Population study showed highest number of youngs in the height class of 0.50-0.75 m while, immatures were recorded highest in the height class of 2.0 to 2.5 m. Majority of the matures belonged to 6-9 m height class while it was recorded maximum in the diameter class of 10-15 cm. Average density of C. gigantea was $0.07individuals\;ha^{-1}$ which varied greatly among different patches with a range of 2 to 14. Significant correlations were found between patch size and density of youngs, immatures, matures and total density. Maximum concentration of youngs was observed in patch size $60-140m^2$, while for immatures, it was highest in patch size $20-160m^2$. Similarly, highest concentration of matures was observed in patch size $20-80m^2$ and $80-180m^2$. Population structure of the total population exhibited inverted pyramid shaped distribution. Population structure consisting of youngs, immatures, matures showed that around 60% patches lack of regenerating individuals which depict very poor natural regeneration of the species. Effective conservation strategies are therefore to be formulated to save C. gigantea from the threat of extinction in near future.

• Journal of the Korean Statistical Society
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• v.32 no.3
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• pp.299-309
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• 2003

Let ${\pi}_1,...,{\pi}_{k}$k($\geq$2) independent logistic populations such that the cumulative distribution function (cdf) of an observation from the population ${\pi}_{i}$ is $$F_{i}\;=\; {\frac{1}{1+exp{-\pi(x-{\mu}_{i})/(\sigma\sqrt{3})}}},\;$\mid$x$\mid$<\;{\infty}$$ where ${\mu}_{i}(-{\infty}\; < \; {\mu}_{i}\; <\; {\infty}$ is unknown location mean and ${\delta}^2$ is known variance, i ＝ 1,..., $textsc{k}$. Let ${\mu}_{[k]}$ be the largest of all ${\mu}$'s and the population ${\pi}_{i}$ is defined to be 'good' if ${\mu}_{i}\;{\geq}\;{\mu}_{[k]}\;-\;{\delta}_1$, where ${\delta}_1\;>\;0$, i = 1,...,$textsc{k}$. A selection procedure based on sample median is proposed to select a subset of $textsc{k}$ logistic populations which includes all the good populations with probability at least $P^{*}$(a preassigned value). Simultaneous confidence intervals for the differences of location parameters, which can be derived with the help of proposed procedures, are discussed. If a population with location parameter ${\mu}_{i}\;<\;{\mu}_{[k]}\;-\;{\delta}_2({\delta}_2\;>{\delta}_1)$, i ＝ 1,...,$textsc{k}$ is considered 'bad', a selection procedure is proposed so that the probability of either selecting a bad population or omitting a good population is at most 1­ $P^{*}$.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.9
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• pp.1237-1246
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• 2013

The objective of this study was to estimate variance components and genetic parameters for lactation milk yield (LY), lactation length (LL), average milk yield per day (YD), initial milk yield (IY), peak milk yield (PY), days to peak (DP) and parameters (ln(a) and c) of the modified incomplete gamma function (MIG) in an Ethiopian multibreed dairy cattle population. The dataset was composed of 5,507 lactation records collected from 1,639 cows in three locations (Bako, Debre Zeit and Holetta) in Ethiopia from 1977 to 2010. Parameters for MIG were obtained from regression analysis of monthly test-day milk data on days in milk. The cows were purebred (Bos indicus) Boran (B) and Horro (H) and their crosses with different fractions of Friesian (F), Jersey (J) and Simmental (S). There were 23 breed groups (B, H, and their crossbreds with F, J, and S) in the population. Fixed and mixed models were used to analyse the data. The fixed model considered herd-year-season, parity and breed group as fixed effects, and residual as random. The single and two-traits mixed animal repeatability models, considered the fixed effects of herd-year-season and parity subclasses, breed as a function of cow H, F, J, and S breed fractions and general heterosis as a function of heterozygosity, and the random additive animal, permanent environment, and residual effects. For the analysis of LY, LL was added as a fixed covariate to all models. Variance components and genetic parameters were estimated using average information restricted maximum likelihood procedures. The results indicated that all traits were affected (p<0.001) by the considered fixed effects. High grade $B{\times}F$ cows (3/16B 13/16F) had the highest least squares means (LSM) for LY ($2,490{\pm}178.9kg$), IY ($10.5{\pm}0.8kg$), PY ($12.7{\pm}0.9kg$), YD ($7.6{\pm}0.55kg$) and LL ($361.4{\pm}31.2d$), while B cows had the lowest LSM values for these traits. The LSM of LY, IY, YD, and PY tended to increase from the first to the fifth parity. Single-trait analyses yielded low heritability ($0.03{\pm}0.03$ and $0.08{\pm}0.02$) and repeatability ($0.14{\pm}0.01$ to $0.24{\pm}0.02$) estimates for LL, DP and parameter c. Medium heritability ($0.21{\pm}0.03$ to $0.33{\pm}0.04$) and repeatability ($0.27{\pm}0.02$ to $0.53{\pm}0.01$) estimates were obtained for LY, IY, PY, YD and ln(a). Genetic correlations between LY, IY, PY, YD, ln(a), and LL ranged from 0.59 to 0.99. Spearman's rank correlations between sire estimated breeding values for LY, LL, IY, PY, YD, ln(a) and c were positive (0.67 to 0.99, p<0.001). These results suggested that selection for IY, PY, YD, or LY would genetically improve lactation milk yield in this Ethiopian dairy cattle population.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.1
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• pp.33-39
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• 1998

Survival, growth and reproduction of the cigarette beetle, Lasiodema sewicome F., were studied on flue-cured (NC82), air-cured (Br.21), aromatic (Izmir) tobacco and artificial diet (wheat feed 95% + yeast 5%). Cigarette beetle adults occurred from first generation in the flue-cured and aromatic tobacco, but no adults emerged in air-cured tobacco after the 2nd generations. The head capsule widths of larvae of the cigarette beetles L sewicome F.1 reared on different diets at 2$0^{\circ}C$, $25^{\circ}C$ and 3$0^{\circ}C$ were measured. The head capsule development was slower at 2$0^{\circ}C$ on the same diets than $25^{\circ}C$ and 3$0^{\circ}C$, and slower in the flue-cured and aromatic tobacco than the artificial diet at 2$0^{\circ}C$ and 2S$^{\circ}C$, At $25^{\circ}C$ the larval head capsule developed more rapidly in the aromatic tobacco than the flue-cured tobacco. However, no larval head development was noticed in the air-cured tobacco. The correlation between population densities of cigarette beetle,1 sewicome F., and sugar content of tobacco leaves was positive, but negative in nicotine contents. The regression between densities and sugar content was Y : 22.79 X + 57.29 (r=0.891**), and between nicotine content was Y : -141.31X + 321.40(r=-0.917**).

• Journal of the Korean Statistical Society
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• v.29 no.2
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• pp.169-185
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• 2000

Given a random sample of size N (unknown) with density f(x│$\theta$), suppose that only n observations which lie outside a region r are recorded. On the basis of n observation, the Bayes estimators of $\theta$ and N are considered and their asymptotic expansions are developed to find the third order asymptotic properties with those of the maximum likelihood estimators and the Bayes modal estimators. The asymptotic m.s.e.'s of these estimators are expressed. An example is given to illustrate the results obtained.

• The Korean Journal of Applied Statistics
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• v.8 no.2
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• pp.87-97
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• 1995

When there is no main effcts or only one main effect in a $2 \times 2$ factorial design, Type I error rates and power for the rank transformed F test (FR test) for interaction are nearly equal to those of the classical F test. However the power of FR test is quite superior under the exponential distribution rather than the of FR test is quite superior under the exponential distribution rather than the normal distribution. Meanwhile when both main effects are in the model, Type I error rates of FR test, compared with those of F test, decrease as the effect size increases and are dependent on the fashion in which main effects are constructed. In addition, the power of FR test increases as the effect size and the sample size increase and is highly dependent on the manner in which main effects are constructed and the type of population distribution.

• Journal of Life Science
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• v.33 no.8
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• pp.632-638
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• 2023

A soybean cultivar with a green seed coat and cotyledon contains high levels of lutein, which is beneficial for eye health. Plus, antinutritional components such as lipoxygenase, Kunitz trypsin inhibitor (KTI), lectin and stachyose exist in the mature seed. The genetic elimination of these antinutritional factors is a necessary step in green soybean breeding. This research was conducted to improve a new green soybean line with the green cotyledon and tetra null genotype (lox1lox2lox3tilers2) in terms of lipoxygenase, KTI, lectin and stachyose. We used five germplasms to develop a breeding population. A total of 69 F₂ seeds were obtained from the cross of parent 1 and parent 2, and from those, 21 F₂ seeds were selected that had the green seed coat color, and which were free of lectin protein. Next, four F₂ plants with the green seed coat and tetra null genotype were selected from the breeding population derived from four genotypes. The absence of lipoxygenase, KTI and lectin proteins was confirmed in the F₅ strain. The breeding line has a green seed coat, green cotyledon and white hilum color. The 100-seed weight and stachyose content for the breeding line were 30.7 g and 2.40 g/kg, respectively. The line selected in this study could be used as a cultivar or parent to improve colored soybean cultivars through the removal of antinutritional components such as lip- oxygenase, KTI, lectin and stachyose.

• Korean Journal of Mathematics
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• v.30 no.1
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• pp.67-72
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• 2022

For a locus with two alleles (I^A and I^B), the frequencies of the alleles are represented by $$p=f(I^A)={\frac{2N_{AA}+N_{AB}}{2N},\;q=f(I^B)={\frac{2N_{BB}+N_{AB}}{2N}$$ where N_AA, N_AB and N_BB are the numbers of I^AI^A, I^AI^B and I^BI^B respectively and N is the total number of populations. The frequencies of the genotypes expected are calculated by using p², 2pq and q². Choi showed the method of whether some genotypes is in these probabalities. Also he calculate the probability generating function for offspring number of genotype under a diploid model( [1]). In this paper, let x(t, p) be the probability that I^A become fixed in the population by time t-th generation, given that its initial frequency at time t = 0 is p. We find adapted equations for x using the mean change of frequence of alleles and fitness of genotype. Also we apply this adapted equations to several diploid model and it also will apply to actual examples.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.11
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• pp.1524-1528
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• 2005

Molecular genetic markers were used to detect chromosomal regions which contain economically important traits such as growth, carcass, and meat quality traits in pigs. A three generation resource population was constructed from a cross between Korean native boars and Landrace sows. A total of 240 F2 animals from intercross of F1 was produced. Phenotypic data on 17 traits, birth weight, body weights at 3, 5, 12, and 30 weeks of age, teat number, carcass weight, backfat thickness, body fat, backbone number, muscle pH, meat color, drip loss, cooking loss, water holding capacity, shear force, and intramuscular fat content were collected for F2 animals. Animals including grandparents (F0), parents (F1), and offspring (F2) were genotyped for 80 microsatellite markers covering from chromosome 1 to 10. Least squares regression interval mapping was used for quantitative trait loci (QTL) identification. Significance thresholds were determined by permutation tests. A total of 10 QTL were detected at 5% chromosome-wide significance levels for growth traits on SSCs 2, 4, 5, 6, and 8.