• Korean Journal of Agricultural Science
• /
• v.43 no.3
• /
• pp.369-378
• /
• 2016

Improving the reproductive traits of Hanwoo might decrease their production cost. Therefore, this study was conducted to investigate the effects of environmental factors [registration grade (basic, pedigree or advanced), birth year, birth season, parity, delivery year, and delivery season] on various reproductive traits (age at 1st service, age at 1st conception, age for 1st calving, days at 1st service postpartum, non-pregnant condition period, calving interval, gestation length, and number of services for conception) in Hanwoo (primiparous 12,219 heads, multiparous 10,471 heads). All data was acquired from Gyeongnam province areas which were surveyed from 2007 to 2015. All environmental factors significantly influenced (p < 0.01) reproductive traits of primiparous cows but, but not all environmental factors influenced multiparous cows. Primiparous cows registered as advanced grade showed significantly lower age at 1st service (by 15.36 days), age at 1st conception (by 8.66 days), and age for 1st calving (by 8.77 days) (p < 0.01) than those registered as basic grades. Age at 1st service, age at 1st conception and age for 1st calving were not significantly related to birth year in primiparous cows. As delivery years advanced from 2005 to 2012, all durations associated to reproductive traits tended to be shorter. Days at 1st service postpartum, non-pregnant condition period, and calving interval tended to be shortened as parity increased. Days at 1st service postpartum, days open, calving interval, and gestation in multiparous cows calved in winter were shorter than those in summer. The registration grade was not a effected with reproductive traits in Hanwoo.

• Journal of the Korean Data and Information Science Society
• /
• v.25 no.3
• /
• pp.533-545
• /
• 2014

Farmers' perception on actual raising conditions and breeding improvement for Hanwoo were surveyed and analyzed in order to utilize such data as basic resources for further development of courses of Hanwoo improvement and instructions on raising techniques. The survey was held based on Hanwoo farmers in Gyeongbuk region and the results for the analysis were as follow. Candidate cattle for breeding was selected in consideration of 'appearance, body shape, and pedigree-registration' (39.0%) and 'artificial insemination' (38.6%) was the most frequently used breeding method for the breeding cattle. 'Body length' was revealed to be the most considered factor while purchasing fattening calves and the castration for the fattening calves were mostly performed when '6~7 months after the birth'. The farmers also responded that they 'try to comply with over 80% of items specified in program for production of high quality beef' in order to produce high quality beef. However, the farmers believed that '12 months after the birth' was the most economic market month. Although the results differed by each items surveyed, majority of those results showed statistically significant differences with significance level of 0.05 upon the surveyees' general characteristics and demographic factors including level of education, age, occupation, and family man power. Most surveyees responded 'around 30% of shipping heads' (22.1%) for the prevalence of beef graded better than 1++ grade when shipping, however, no significant differences in between general characteristics of surveyees were observed.

• Horticultural Science & Technology
• /
• v.34 no.3
• /
• pp.488-494
• /
• 2016

To develop appropriate potato clones as functional food materials, we collected 35 potato breeding clones to analyze the contents of the total polyphenol, anthocyanin, and vitamin C with the 'Superior', 'Dasom valley', and 'Gogu valley' cultivars as controls. Based on our analysis great differences were observed in different potato clones. KPG16 had the highest content of total polyphenol at $105.08mg{\cdot}100g^{-1}\;FW$; KPG13 had the highest content of anthocyanin at ${\cdot}4.78mg100g^{-1}\;FW$; KPG20 had the highest content of vitamin C at $22.16mg{\cdot}100g^{-1}\;FW$. Some clones had higher contents of the total polyphenol but lower levels of anthocyanin. Ultimately, potato clones showing relatively high indexes for all three compounds, could be considered as good functional food material. By equilibrium analysis of the contents of total polyphenol, anthocyanin, and vitamin C, KPG5 showed relatively higher contents, with values of 103.95, 3.15, $12.12mg{\cdot}100g^{-1}\;FW$, respectively. Therefore, KPG5 was considered to be the best potato breeding clone in view of a functional potato breeding system.

• Horticultural Science & Technology
• /
• v.34 no.1
• /
• pp.142-153
• /
• 2016

The present study investigated identification of cultivars through phylogenetic analysis of 108 Citrus varieties and related cultivars using simple sequence repeat (SSR) markers. Two hundred three SSR primer pairs were used to detect polymorphic markers among 8 Citrus cultivars consisting of 4 mandarins, 1 orange, 1 tangor, 1 tangelo, and 1 pumelo. Eighteen SSR primer pairs were reproducible and showed highly polymorphic alleles. These markers were applied to assess genetic variations of the 108 varieties. Each marker detected 5-14 alleles, with an average of 9.28. The polymorphism information content varied from 0.417 to 0.791 with an average of 0.706. Cluster analysis with SSR markers resulted in 13 major groups reflecting cultivar types and pedigree information. Twelve orange cultivars in the $I-1^{st}$ sub-cluster and 23 mandarin cultivars in the $II-1^{st}$ sub-cluster, respectively, were not discriminated using the SSR markers. This could be due to narrow genetic backgrounds originated through bud mutation or nucellars seedlings. The SSR profile database of Citrus cultivars will be useful as a tool for protection of plant breeders' intellectual property rights in addition to assessing genetic diversity in Citrus cultivars and germplasms.

• Journal of agriculture & life science
• /
• v.46 no.5
• /
• pp.57-63
• /
• 2012

The purpose of this study was to estimate genetic parameters for productive traits in Duroc breed. In this study, 40,657 records for productive traits and the pedigree data of 47,974 families were collected from 41 farms registered at the Korean Animal Improvement Association (KAIA) from 2004 to 2011. The REMLf90 program was used to analyze a multiple traits animal model with fixed effects of sex, contemporary group, parity and age at the end of the test as covariate and random effects of animal and residual error. The heritabilities of days to 90 kg (D90KG), average daily gain (ADG), backfat thickness (BF) and eye muscle areas (EMA) were estimated to be 0.334, 0.340, 0.335, and 0.200, respectively. The genetic correlation coefficients were -0.992 between D90KG and ADG, -0.142 between ADG and BF, -0.361 between ADG and EMA, and -0.243 between BF and EMA. Conversely, positive genetic correlations for D90KG with BF and EMA were 0.13 and 0.36, respectively.

• Korean Journal of Breeding Science
• /
• v.41 no.4
• /
• pp.574-578
• /
• 2009

A new red leaf lettuce (Lactuca sativa L.) cultivar, "Gopungjeokchukmyeon" which has late bolting and good red expression leaf color was developed from a cross between "Andongjeokchukmyeon" (red leaf color and late bolting) and "Dukseomjeokchukmyeon" (high yield). The cross and selection for advanced lines had been done by the pedigree method during 2000-2006. The advanced lines were evaluated for yield and adaptability at several locations in Korea (Gangwon, Kyunggi, Chungbuk, Kyungnam, Jeonnam, Jeonbuk, and Jeju) from 2007 to 2008. The "Gopungjeokchukmyeon" has gray seed color and traverse elliptic leaves. Compared to "Dukseomjeokchukmyeon", marketable yield of "Gopungjeokchukmyeon" was higher by 17% (at 330 g per plant) and Gopungjeokchukmyeon has particularly improved expression of red leaf color in high temperature cultivation in the field. The shelf-life of "Gopungjeokchukmyeon" was three weeks longer than "Dukseomjeokchukmyeon" at $4^{\circ}C$. The anthocyanin and sugar contents of "Gopungjeokchukmyeon" were higher than those of "Dukseomjeokchukmyeon" with 29.4 mg/100 g and 4.8 brix, respectively. The content anthocynin of "Gopungjeokchukmyeon" is about 10 times higher than those of "seomjeokchukmyeon". Furthermore, its taste is better, more crispy, and sweeter than those of "Dukseomjeokchukmyeon", This new cultivar "Gopungjeokchukmyeon" can be harvested all year around even summer cultivation.

• Korean Journal of Breeding Science
• /
• v.41 no.4
• /
• pp.579-582
• /
• 2009

A new red leaf lettuce (Lactuca sativa L.) cultivar, "Mihong" which has late bolting and deep red leaf color was developed from a cross of "Danhongongchukmyeon" (deep red but early bolting and low yield) and "Hajicheongchukmyeon" (late bolting and high yield). The selection and breeding of advanced lines were done by pedigree method during 2000-2006. The advanced lines were evaluated for yield and adaptability in Korea (Gangwon, Kyunggi, Chungbuk, Kyungnam, Jeonnam, Jeonbuk, and Jeju) from 2007 to 2008. The "Mihong" has gray seed color, traverse elliptic leaves and deep red color. Compared to "Dukseomjeokchukmyeon", marketable yield of "Mihong" was higher by 2% (at 291 g per plant) as a 17.3 ton/ha, but with particularly improved good expression of deep red leaf color in high temperature cultivation in the field. The shelf-life of "Mihong" was three weeks longer than "Dukseomjeokchukmyeon" at $4^{\circ}C$. The amount of anthocyanin content of "Mihong" were higher than with "Dukseomjeokchukmyeon" at 28.9 mg/100 g. Especially the degree of leaf hardness in "Mihong" showed $26.9kg/cm^2$ compared to "Dukseomjeokchukmyeon". therefore, its taste is better, more crispy, and sweeter than "Dukseomjeokchukmyeon" This new cultivar "Mihong" can be cultivated in all year around even if summer time cultivation.

• Korean Journal of Breeding Science
• /
• v.41 no.3
• /
• pp.319-323
• /
• 2009

Strawberry is an out-crossed crop that is relatively sensitive to inbreeding, and as a result, most of breeding programmes in strawberry have been based on selection breeding where elite parents are selected from intercrossing. Also, pedigree breeding has been successfully employed in a number of instances to concentrate genes of interest. Therefore, in order to obtain inbred line having the genotype of excellent combining ability by selfing and incrossing to improve breeding efficiency of strawberry, elite varieties were self-pollinated. From the selfing line of "Benihoppe" cultivar, we selected "Wongyo 3111" having excellent horticultural traits such as plant vigor, sugar content and fruit hardness among these progenies. "Wongyo 3111" shows erect plant type, vigorous growth habit, early flower bud differentiation with 16~17 flowers per cluster. Fruits of "Wongyo 3111" are conical type having a bright red skin color, and 17.2 g in an average weight. Also that have a relatively more high sugar/acid ratio and firmness than check cultivars as sugar content of 11.3oBx, acidity of 0.50% and firmness of 21.7 g/$mm^2$. But although yield of "Wongyo 3111" is not significantly different from check cultivars, its marketable yield is remarkably lower than that of check cultivars because of poor fruit-setting under low temperature. Disease and pest reactions of "Wongyo 3111" are more sensitive to powery mildew, anthracnose and spotted spider mites than check cultivars. Therefore, "Wongyo 3111" is suitable for intermediate parent line better than as a cultivation cultivar.

• Korean Journal of Breeding Science
• /
• v.42 no.3
• /
• pp.226-230
• /
• 2010

'Gwanghan' (Avena sativa L.), a winter oat for forage use, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, NICS, RDA in 2009. It was derived from a cross between 'Early80' and 'Gwiri23'. A parent, 'Early80', has early heading and high yielding, while Gwiri23 has mid-heading with large-size grain. Subsequent generations followed by the cross were handled in bulk and pedigree selection programs at Suwon and Yeoncheon, respectively. A line, 'SO96016-B-112-YB-12-7', was selected for earliness, cold tolerance, and good agronomic characteristics and designated as a line name of 'Gwiri64'. The line was subsequently evaluated for cold tolerance, earliness, and forage yield in four different locations, Yesan, Iksan, Kimjae, and Jeju, from 2007 to 2009, and finally named as 'Gwanghan'. Over 3 years, the average forage dry matter yield of 'Gwanghan' harvested at milk-ripe stage was $16.4MT\;ha^{-1}$, compared with $15.4MT\;ha^{-1}$ of check cultivar 'Samhan'. 'Gwanghan's' heading date is about 3 days earlier than that of check cultivar, and is adapted primarily for winter cultivation in the mid-southern regions of Korean peninsula.

• Korean Journal of Breeding Science
• /
• v.43 no.5
• /
• pp.422-429
• /
• 2011

This study was conducted to investigate the genetic diversity and to develop a technique for cultivar identification using SSR markers in grapevine. Thirty Korean bred and introduced grapevine cultivars were evaluated by 28 SSR markers. A total of 143 alleles were produced ranging from 2 to 8 alleles with an average of 5.1 alleles per locus. Polymorphic information contents (PIC) were ranged from 0.666 (VVIp02) to 0.975 (VVIn33 and VVIn62) with an average of 0.882. UPGMA (unweighted pair-group method arithmetic average) clustering analysis based on genetic distances using 143 alleles classified 30 grapevine cultivars into 7 clusters by similarity index of 0.685. Similarity values among the tested grapevine cultivars ranged from 0.575 to 1.00, and the average similarity value was 0.661. The similarity index was the highest (1.00) between 'Jinok' and 'Campbell Early', and the lowest (0.575) between 'Alden' and 'Narsha'. The genetic relationships among the 30 studied grapevine cultivars were basically consistent with the known pedigree. The three SSR markers sets (VVIn61, VVIt60, and VVIu20) selected from 28 primers were differentiated all grapevine cultivars except for 'Jinok' and 'Campbell Early'. Five cultivars ('Narsha, 'Alden', 'Dutchess', 'Pione', and 'Muscat Hamburg') were identified by VVIn61 at the first step. Then 21 cultivars including 'Hongsodam' by VVIt60 at the second step and 2 cultivars ('Heukbosuck' and 'Suok') by VVIu20 at the third step were identified. These markers could be used as a reliable tool for the identification of Korean grapevine cultivars.