• Asian Journal of Turfgrass Science
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• v.22 no.1
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• pp.13-24
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• 2008

This study was carried out to provide basic information for the breeding of zoysiagrass synthetic varieties. For estimation of flowering periods, genetic characteristics, and cross-pollination rate, 5 combinations of zoysiagrass breeding lines were compared. Days to stigma emergence and anther exertion were observed in the field to calculate overlapping dates for cross-fertilization. Harvested seed from cross breeding combinations were planted to compare genetic characteristics using morphological traits of progenies. These data were used for determination of 7 phenotypic inheritance types with 8 morphological traits. Cross-pollination rates in 3 combinations of zoysiagrasses were estimated by using lower part color of grass shoots. Cross-pollination rates of zoysiagrass ranged from 11.3$\sim$48.9%, which indicated that zoysiagrass is an allogamous plant. When zoysiagrass breeding lines are properly combined, they may result in valuable synthetic cultivars.

• Korean Journal of Ichthyology
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• v.24 no.3
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• pp.151-159
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• 2012

Cross and reciprocal hybrids from intrageneric crosses between Rhodeus uyekii and R. notatus were analyzed morphometrically using truss and classical dimensions, erythrocyte size using blood smears, and cytogenetically using flowcytometry, then compared with the parental species. Although the morphometric assessment based on body proportions indicated that the hybrids were generally intermediate between the maternal and paternal species, the morphometric characters of cross and reciprocal hybrids included at least 14 paternal-like and 7 maternal-like, and 13 paternal-like and 5 maternal-like characters, respectively (P<0.05). The pigmentation of the hybrids was intermediate in some respects, and resembled that of the parental species. The DNA content of the cross and reciprocal hybrids, based on flow cytometry analysis, was significantly different from the parental species. The characterization of morphometric traits and the cytogenetic analysis of hybrids of R. uyekii and R. notatus used in this study may be useful for distinguishing genotypes in commercial Acheilognathinae aquaculture.

• Horticultural Science & Technology
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• v.32 no.1
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• pp.77-83
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• 2014

To improve the breeding efficiency of oriental pear, the inheritance of major fruit traits were analyzed using 4,035 seedlings of 15 cross combinations combined with 13 cultivars. Yearly variation of parental cultivars, broad-sense heritability of the traits, and frequency of seedlings with commercially acceptable characteristics by the mid-parent values were studied. Despite the heritabilities of traits related with pear the fruit texture were different depending on cross combination, the average narrow-sense heritability ($h^2$) for firmness, flesh hardness, flesh density and grit were over 0.6, a relatively high value. However fruit firmness showed different heritability among the cross combination and its value of cross combination between 'Niitaka' and 'Choju' was very low as 0.11. Positive correlation was not observed on fresh hardness, fresh density and grit but observed on firmness between mid-parent value and average value of offspring. Regression of offspring on firmness, fresh hardness, fresh density and grit between mid-parent value and average value of offspring were 0.778, 0.343, -0.273, 0.313, respectively. Frequency distributions of fruit texture in 15 cross combinations of pear seedling was influenced by parental characteristics. When fruit firmness was estimated as low, low ${\times}$ high and high ${\times}$ high values in parental fruits, firmness in their offspring exhibited low, medium and high, respectively. In addition, when parental grit by sensory evaluation were light ${\times}$ light and light-medium ${\times}$ medium-heavy, most of offsprings showed light and medium grit, respectively.

• Journal of Aquaculture
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• v.13 no.4
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• pp.325-330
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• 2000

For development of all male seed production at hatchery scale, a comparative study was made on the seed production traits of supermale (IT - t) and superfemale (IT - L1 ~) Nile tilapia, Oreochromis niloticus. Supermales were crossed with normal females (XX- f) and the superfemales with normal males (XY - t ) or sex reversed males (XX- L1 t); progeny survival of these crossings and sex ratio were evaluated. Hatching success of the eggs, fertilized by the supermale was significantly lower than that by the normal male. Over 95-99 % progenies sired by crossing supermales with normal females were males, while 52-55 % progenies alone were males with the cross of normal males and normal females. Hatching success and survival of alevins were significantly higher for the progenies of the crosses between superfemales and sex reversed males than those resulting from the crosses between superfemales and normal males. However, there was no significant difference in the sex ratio among the progenies of these crosses. Therefore, crossings of superfemales with sex reversed males provide the highest percentage of survival and male progenies.

• The Korean Journal of Mycology
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• v.31 no.2
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• pp.98-102
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• 2003

Metalaxyl sensitivity related with distribution feature of mating type was characterized far Phytophthora capsici population, totally 433 isolates of the red-pepper pathogen collected from 75 pepper fields in Korea from 1995 to 1998. At the concentration of metalaxyl $2{\mu}g/ml$, inhibition rate of mycelial growth of P. capsici isolates was 68.2% in average compared to control, and 28.6% isolates in average were estimated as resistance to the chemical. Isolates of field unit with a single mating type revealed similar level of sensitivity to metalaxyl and showed sensitive or resistant in most field units. However, isolates of field units with both mating types revealed diverse sensitivity level to the chemical and various occurrence ratio of metalaxyl sensitive : resistant in each field unit. Results indicated that different levels of metalaxyl sensitivity of P. capsici population in Korea seem to be closely related with occurrence ratio of A1 : A2 mating type of each field.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.5
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• pp.649-654
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• 1995

This study was conducted to investigate the utility and agronomic characteristics and use of cytoplasmic. male-sterile (CMS) haploid plants derived from interspecific cross between (male-sterile NC82$\times$burley21) F$_1$ plant (Nicotiana tabacum L.) and Nicotiana africana. Abundant seeds of high germinability were obtained when Nicotiana tabacum (cytoplasmic male-sterile F$_1$ plants) is pollinated by Nicotiana africana. Most of seedlings died at the cotyledonary stage. The remaining seedlings are viable F$_1$ hybrids or maternal haploids that can be easily distinguished. Number of interspecific Fl hybrids and matermal haploids per capsule obtained from the interspecific cross between cytoplasmic male-sterile tobacco F$_1$ plants and N.africana yielded 2.2 and 0.5 plants, respectively. Out of 149 CMS haploid plants obtained from interspecific cross, 102 plants showed green type while the others were yellow type for leaf and stem. This results agreed with the genetic ratios expected among haploid plants from the F$_1$ hybrids heterozygous for two recessive genes of yellow color of burley tobacco plant. Out of 83 CMS haploid plants inoculated with TMV, 48 plants showed resistant, while the others was susceptible. It agreed with the expected genetic ratios for a single dominant gene of TMV resistance. CMS haploid plant will be useful as a source material for breeding of CMS doubled haploid lines

• Korean Journal of Environment and Ecology
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• v.32 no.1
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• pp.47-54
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• 2018

This study examined the behavior of red fox (Vulpes vulpes) during the estrus period, breeding period, and mating including the estrus period along as well as the effect of environmental factors in an outdoor breeding facility. The average mating duration was 19.95 min (n = 13, range = 1.17-35.25 min). The breeding season was mainly early February (56.6%) for foxes aged more than one year and mid-March (60.0%) for foxes aged less than one year. The mating duration was longest when both male and female were more than one year old ($24.4{\pm}11.08min$), although copulation took place regardless of partner's age. Females that mated twice within two days after estrus started or with two males had 100% pregnancy rate. In addition, the pregnancy rate was highest (87%) when both mating partners were more than one year old. Foxes preferred daytime to nighttime for mating, and thus mating usually took place on sunny days or between 10:00 and 12:00 on partly cloudy days. A male mated with different females for a maximum of five times, and the higher the mating frequency of a male, the longer the mating duration. Interest in mating decreased after three copulations in the case of males and after two copulations in the case of females. Males required at least 4 hours and 46 minutes between the first and second copulation. For this study, we collected reference data that might be applied to breeding programs for the red fox to secure the restoration of individuals of this important species.

• Korean Journal of Medicinal Crop Science
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• v.15 no.6
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• pp.391-397
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• 2007

To develop new high valuable Gugija (Lycium chinensis), biofunctionalities of Gugija standard species and its hybrids were investigated and compared with each water extracts and methanol extracts from Lycii Fructus, Lycii Folium and buds and Lycii Cortex Radicis. Among various biofunctionalities of Gugija standard species, antioxidant activity was showed the highest in methanol extracts from buds of Cheongwoon species (93%) and antihypertensive angiotensin I-converting enzyme (ACE) inhibitory activity was 84.1% in the water extracts from Lycii Cortex Radicis of Cheongyang NO.7. Futhermore, methanol extracts from Lycii Cortex Radicis of Myungan A-2 hybrid showed 93.1% of antioxidant activity and 96.9% of ACE inhibitory activity was also showed in the methanol extracts from Lycii Fructus of DO148-72(A11) hybrid. However, fibrinolytic activity and anticholesteromia HMG-CoA reductase inhibitory activity were weak or not detected in almost of Gugija standard species and its hybrids. Therefore, we finally selected Cheongwoon Gugija standard species (buds) and Myungan A-2 hybrid (Lycii Cortex Radicis) as good antioxidant sources and also DO148-72 (A11) hybrid (Lycii Fructus) as excellent antihypertensive ACE inhibitior sources for manufacturing functional food product.

• Journal of Life Science
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• v.12 no.3
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• pp.256-263
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• 2002

This study was carried out to estimate the degree of heterosis and heterobeltiosis, and the heritability and genetic correlation in F$_1$hybrid produced by reciprocal crosses between two six-rowed hulled barley (Gangbori and Olbori) and three six-rowed naked barley (Saechalssalbori, Saessalbori, and Moodeongssalbori). Heterosis was observed positively in traits such as cults length, spike length, awn length, leaf length, leaf width, number of spikes per plant, number of grains per spike, and 1000 grain weight. Heterosis and heterobeltiosis from the crosses with hulled barley as a material parent showed higher performance in culm length, leaf length, leaf width, number of spike per plant, number of grains per spike. The hulled grain characteristics is dominant over the naked one. The highest heritability was confirmed in leaf width with a value of 94.5% and overall high heritability was observed in most traits with the range from 76.7% to 94.5%. In an analysis of correlation coefficient, higher genetic correlations were observed between leaf length and number of spikes per plant(0.970), between cults length and number of grains per spike(0.963), and between awn length and leaf length(0.862) in the forward crosses in which hulled barley was maternal. In the reverse crosses, higher genetic correlation was observed between culm length and spike length(0.926), between awn length and leaf length(0.922), and between number of spikes per plant and number of grains per spike(0.713).

• FLOWER RESEARCH JOURNAL
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• v.16 no.2
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• pp.118-123
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• 2008

For effective production of interspecific hybrids of Lilium and valuable new cultivars, we used Lilium Asiatic hybrid 'Tiny Ghost' as the female parent, and Oriental group, and Longiflorum group and Martagon as the male parents. Percentage pollen germination in Oriental hybrid 'Sorbonne' was the highest with 64%. As results of using normal style pollination and cut style pollination methods, all seed sets were formed in normal style pollinated treatment, except in 'Aktiva'. Pollen germination percent of Longiflorum hybrid 'Norina' was higher than that 'Gelria'. However, all crossings using 'Norina' failed to set seeds. Corresponding fertilization ratio was different from genetic compatibility, even in the same group. From the crossing using 'Aktiva' as the male parent one bulb was obtained derived from one embryo sac. And using 'Sorbonne' as the male parent, one plantlet was obtained after four ovule cultures. Crossing using 'Gelria' as the male parent five embryos, 15 embryo sacs, and seven ovules per one ovary were obtained. Among them, 18 plantlets germinated, with the germination percent of 66.7%. Crossings using L. hansonii, Martagon group, as the male parent resulted in 40% germination from five ovules.