Soybean [Glycine max (L.) Merrill]: Importance as A Crop and Pedigree Reconstruction of Korean Varieties

Transcription

1 Plant Breed. Biotech (September) 3(3):179~196 REVIEW ARTICLE Online ISSN: Print ISSN: Soybean [Glycine max (L.) Merrill]: Importance as A Crop and Pedigree Reconstruction of Korean Varieties Chaeyoung Lee 1, Man-Soo Choi 2, Hyun-Tae Kim 2, Hong-Tai Yun 2, Byungwook Lee 3, Young-Soo Chung 4, Ryan W. Kim 3, Hong-Kyu Choi 4 * 1 Department of Medical Bioscience, Dong-A University, Busan , Republic of Korea 2 National Institute of Crop Science, Rural Development Administration, Daegu , Republic of Korea 3 Korea Bioinformation Center, Korea Research Institute of Bioscience & Biotechnology, Daejeon 34141, Republic of Korea 4 Department of Genetic Engineering, Dong-A University, Busan , Republic of Korea ABSTRACT Soybean [Glycine max (L.) Merrill] is one of the most important crops in the world and in Korea as well. Since the official start of soybean breeding program in Korea at which a landrace Jangdanbaekmok was first released to promote cultivation in 1913, approximately one century has elapsed. Currently, a total of 178 soybean varieties are registered at two representative Korean national institutes, the RDA-Genebank Information Center ( and the Korea Seed & Variety Service ( Of these, 155 varieties (87.1%) have been developed through hybridization-based breeding technologies, of which most cultivars (133 varieties, 85.8%) have been released in the last twenty five years. In this review, we attempted to integrate all the information for individual cultivars and to rebuild a breeding pedigree including the entirety of registered Korean soybean varieties. The analysis has resulted in a total of four pedigrees involving 168 cultivars (94.4% out of 178 cultivars), which form the broadest network of pedigrees. Each of pedigrees highlights different key varieties within the context of progenitor networks derived from crossing of various elite parental lines as follows; pedigree I- Kwangkyo, Hwangkeumkong, Paldalkong and Sinpaldalkong2, pedigree II- Baegunkong, Jangyeobkong and Keunolkong, pedigree III- Danyeob, Pangsa and Eunhakong. These pedigrees also reveal purpose (i.e., desirable traits)-driven development of characteristic soybean varieties during the past century of breeding history in Korea. We expect that the pedigree reconstructed in this study will provide breeders with information useful to design breeding schema and guidance towards the genomics-assisted soybean improvement in the future. Keywords Soybean, Pedigree analysis, Breeding, Genetic diversity INTRODUCTION Soybean [Glycine max (L.) Merrill] is apparently one of the most important cultivated crops worldwide in its agro-economic value and diverse utilities in both agriculture and industry. The legume family, which contains this crop, is composed of approximately species, which is the third largest group among flowering plants, and includes other agriculturally important legume crops such as common bean (Phaseolus vulgaris), mung bean (Vigna radiata) and pigeon pea (Cajanus cajan). Among many other evolutionary branches within the family, Phaseoloid clade harbors most of important crop legumes of agricultural importance, within which soybean is a member of this clade (Choi and Cook 2011). It is generally known that distribution of the wild soybean (G. soja), which is the ancestor of current cultivated soybean, is limited to the East Asia regions including China, Korea and Japan. Historical records have addressed that the first cultivation of soybean originated in China, which was approximately 4500 years ago (Qiu and Chang 2010). Shu, which is ancient Chinese character meaning soybean, has been frequently found in ancient Chinese books. In addition, carbonized remain of soybean seeds, which was estimated to be 2600 years old, were discovered in an excavation site of the Eastern Zhou Received September 10, 2015; Revised September 25, 2015; Accepted September 28, 2015; Published September 30, 2015 *Corresponding author Hong-Kyu Choi, hkchoi@dau.ac.kr, Tel: , Fax: These authors are equally contributed Copyright c 2015 by the Korean Society of Breeding Science This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

2 180 Plant Breed. Biotech (September) 3(3):179~196 Dynasty (Qiu and Chang 2010). Although its cultivation history dates back to ancient age, soybean actually came to prominent crop during the last 200 years (Singh and Shivakumar 2010). Because of such a long history of cultivation and natural/artificial selection, which was the natural breeding process itself, China had been the world s top producer until the first half of the 20 th century. However, the situation had been reversed by the USA in the 1950s. It is known that soybean was first cultivated in the USA as early as 1765 (Hymowitz 1984). During , the USA sent scientist to collect soybean germplasm in China, Korea and Japan, and some of germplasm played a pivotal roles as primary parents to breed the current USA cultivars (Qiu and Chang 2010). Using those collected accessions, the USA rapidly developed breeding program and accelerated the production of soybean, and thereafter the country has now become not only the highest producer but also largest exporter all across the world. In the USA, soybean is now the second largest crop, right after corn, in production. Korea also has a significantly long history of domestication and cultivation of soybean, which is comparable to that of China and dates back to the ancient Chulmun period ( BC). A recent archeological study shows that charred soybean seeds discovered in Pyeonggeodong around the Nam River valley are as old as years (Lee et al. 2011). Thereafter soybean continued to remain an important crop in Korea throughout the ancient Mumun period followed by the Three Kingdom periods. Interestingly, the study also addresses that soybean domestication occurred independently in multiple regions of the East Asia and landraces with larger seeds were adapted in Korea and Japan far earlier than in China (Lee et al. 2011). Although Korea is one of the East Asian countries of soybean origin and cultivation, start of systematic breeding programs were relatively delayed. The first Korean cultivar bred by hybridization method Kwangkyo was recently developed in Soybean is still important as one of main crops in Korea, which is the third after rice and wheat, and its production in1975 could almost fill up 98% of domestic need. Since then, the rate of self-sustenance has gradually decreased and is now only 8.7%, thereby causing severe dependence on the GMO soybean imported from the USA. Soybean is cultivated in enormous area of arable land worldwide, which accounts for 90.2 million ha, resulting in a total production of about 276 million ton (MT) in 2013 (FAO 2013). Among major producing countries, the USA is the top producer (28.2% and 32.2%), by both area and production, followed by Brazil (23.7% and 27.5%), Argentina (18.5% and 21.2%) and China (9.7% and 7.0%), respectively (Soytech Inc. 2007). In comparison to the total production of the world, Korea produced relatively small amount of soybean (0.16MT) in 2013 (FAO 2013). Presumably, the most prominent purposes for soybean cultivation should be its high contents of protein and oil, which make up approximately 40% and 20%, respectively. In the Western world of North America and Europe, soybean is mainly regarded as oil crop or protein source for animal feed. In other countries of the Eastern World, this crop is consumed mainly by human in various forms of foods, such as bean curd (tofu), soy milk, sprout, soy paste/sauce. Soybean also has a diverse array of utilities in industry and has been used for the production of lubricants, toner ink, cosmetics and for many other purposes. In more recent years, this crop is increasingly drawing interest of scientists as a useful biofuel source. Although soybean production in Korea has gradually decreased during the past 40 years, its importance as a major crop has not diminished probably because soybean has a long history of cultivation associated intimately with traditional food culture of Korea. Recent completion of soybean whole genome sequencing (Schmutz et al. 2010) may promote the development of new technologies for soybean molecular breeding. Moreover, recently developed technology of the next generation sequencing (NGS) and a variety of bioinformatic tools can play a critical role in processing and analyzing biological big data. NGS-driven bioinformatic data processing enables researchers to analyze population level of resequencing and transcriptome data. Hence, collection and organization of useful germplasm and their phenotypic characterization in precision are becoming more and more important. To effectively select germplasm for the data analyses, it is essential to know relationships among a variety of cultivars, landraces and wild accessions. Towards this end, this review intends to integrate all available data and information, and provide a

3 Soybean [Glycine max (L.) Merrill]: Importance as A Crop and Pedigree Reconstruction of Korean Varieties 181 pedigree-based view of Korean soybean varieties, with a high expectation for making a constructive use of the pedigree information to breed a diverse array of soybean varieties with superior traits in the future. A brief history of soybean breeding in Korea According to a recent archeological study, it has been known that the cultivation and domestication of soybean in Korea was evidenced back in ancient era of the Chulmun period, which was approximately 4000 year ago. In spite of such a long history of cultivation, a memorable moment towards the development of cultivation methods and systematic crop improvement initiated officially with the first cultivar Jangdanbaekmok, which was derived from landrace through pure line selection breeding, and was recommended for farmers to grow and cultivated nationwide until the first hybridization-bred variety Kwangkyo was developed. This cultivar was grown and used for soy sauce/paste and beared medium-to-large seeds. Before cross breeding technology was actively used, most varieties were developed by selecting pure lines or directly introduced from other countries such as the USA and Japan. At the early developmental stage of new cultivars, breeding purposes mainly focused on improvement of qualities associated with yield and easiness in cultivation. In 1960s, 6 Korean landraces ( Haman, Chungbukbaek, Keumgangdaelip, Buseok, Iksan, including Jangdanbaekmok ) and Yukwoo3, which was introduced from Japan, were released for the purpose of cultivation. Thereafter, two cultivars, Hill and Shelby, were introduced from the USA in 1967 and 1968, respectively. In the next year, Kwangkyo, which was the first variety developed by hybridization-based breeding, was released to farmers. Kwangkyo was developed using Jangdanbaekmok as maternal line and Yukwoo3 as paternal line, and thereafter was frequently employed to develop many other cross-bred varieties. In 1970s, both Korea-bred and introduced varieties were supplied for the cultivation in parallel manner, and breeding came to further focusing on development of cultivars adaptive to mechanized farming because of a social phenomenon of the rural exodus. Influenced by such change in social environment, Muhankong (Hong et al. 1989), Jangkyongkong (1988), Jangsukong (Hong et al. 1991), which were resistant to lodging and indeterminate type with relatively longer stem length, were developed for mechanized farming and released in 1980s. In 1986, Eunhakong (Shin et al. 1988), which was first bred for bean sprout, was released. Until 1990s, soybean breeding mainly focused on qualities in appearance, stress resistance and useful chemical ingredients in seeds. Since 1995, soybean breeding has gradually switched to upgrading crop qualities and diversifying uses to compete cheaper GMO soybeans imported from open international market of the agricultural products. As a result, many varieties with desirable qualities were developed and released, some of which included Danbaek (Soybean Breeding Team 1994a), Kwangankong (Soybean Breeding Team 1994b) with higher protein content, Jinpumkong (Kim et al. 1995) with no fishy smell and Geomjeongkong 1 (Soybean Breeding Team 1994c) suitable for cooking with rice. After 2000s, soybean breeding has more focused on the improvement of quality for processing, functional ingredients, seed appearance and mechanized farming. Previous pedigree studies of soybean varieties in Korea It appears that pedigree analyses for Korean soybean varieties were intermittently made by a limited number of breeding researchers. Jong et al. (1999) conducted CP (coefficient of parentage)-based clustering analysis for 75 soybean varieties released during The analysis ended up with separation of the varieties into nine clusters. In the next year, the same group of researchers performed a similar pedigree analysis for 53 varieties bred by hybridization method and released during (Jong et al. 2000). It is currently thought that the pedigree study in 2006 was the most recent one done by the same research team (Jong et al. 2006). In that study, they analyzed pedigree using a total of 86 cultivars bred between 1933 and They also attempted to compare genetic relationships among cultivars by pedigree analysis and DNA finger printing method (Jong et al. 2006). However, any other noticeable research of pedigree analysis for Korean soybean varieties has not been found, although considerable amount of time has elapsed since

4 182 Plant Breed. Biotech (September) 3(3):179~196 then. Thus we intended to update and reconstruct the pedigrees by integrating data and/or information on recently released soybean varieties in this review. Data/ information resources and current status of soybean breeding in Korea In an attempt to reconstruct the Korean soybean pedigree, previous analyses done by Jong et al. (1999, 2000, 2006) played a skeletal role in rebuilding the pedigree. The majority of relevant information was obtained from the RDA-Genebank Information Center (GBIC; genebank.go.kr) and the Korea Seed & Variety Service (KSVS; seed.go.kr). Basic information on all registered cultivars/varieties is provided in Table1 and Table 2. The data reveals that a total of 178 soybean varieties have currently been registered at the two national institutes. Fig. 1 demonstrates their basic information for all these varieties according to their uses, breeding methods and timelines at which they were developed. It is apparent that soybean varieties for soy sauce and tofu predominate in Korea while ones for vegetables are relatively minor (Fig. 1A). Of 178 registered accessions, the majority of varieties (155, 87.1%) have been developed by hybridization-based breeding methods (Fig. 1B). Since the first hybridizationbred Korean variety Kwangkyo was released, seven more varieties were added in 1970s as recommended cultivars. These include Bong-Eui, Kang-lim, Baegcheon (Choi et al. 1978), Jangyeobkong, which were developed by hybridization method and three introduced varieties, Eundaedu, Dongpuk-tae, Danyeobkong (Essex). It is noteworthy that new varieties have been increasingly developed almost exclusively by hybridization methods and registered since 1980s (Fig. 1C). It is also noticeable that more than one third of varieties (68 cultivars, 38.2%) were emerged during the period of 2000s, which implicated that previously developed varieties played nodal roles to provide a diverse array of progenitors for soybean breeding. Fig. 1. Summary of 178 registered Korean soybean cultivars. A. Distribution of cultivars according to utilization. It is classified into four categories; vegetable & early maturity, soy sauce & tofu, bean sprout and cooking with rice. B. Classification of soybean cultivars according to their origin of development. C. Distribution of soybean varieties according to their registered timeline.

5 Soybean [Glycine max (L.) Merrill]: Importance as A Crop and Pedigree Reconstruction of Korean Varieties 183 Table 1. Summary of Korean soybean varieties according to their utilization. Released time periods 1913~ s 1980s 1990s 2000s 2010s Breeding mathods Korea landrace Vegetable & early maturity Soy sauce & Tofu Bean sprout Cooking with rice - Jangdanbaekmok, Chungbukbaek, Iksan, Buseok, Haman, Keumgangdaelip, Keumgangsolip, Kwangdu - - Hybridization - Kwangkyo - - Introduction - Yukwoo3, Shelby Hill - Korea landrace Hybridization - Bong-Eui, Kang-lim, Baegcheon, Jangyeobkong - - Introduction - Eundaedu, Dongpuk-tae Danyeobkong - Korea landrace Hwangkeumkong, Jangbaegkong, Namcheonkong, Togyukong, Hybridization - Milyangkong, Baegunkong, Pangsakong, Eunhakong, Saealkong, Paldalkong, Namhaekong Pokwangkong, - Dankyeongkong, Muhankong, Jangkyongkong, Jangsukong, Danweonkong Introduction Korea landrace Keunolkong, Hwaseongputkong, Geomjeongolkong Hybridization - Introduction Korea landrace Hybridization Hwaeomputkong, Seokryangputkong - - Heugcheongkong, Galmikong Manlikong, Sinpaldalkong, Bukwangkong, Kwangankong, Taekwangkong, Samnamkong, Pureunkong, Hannamkong, Sinpaldalkong2, Myeongjunamulkong, Danbaekkong, Duyoukong, Iksannamulkong, Soyangkong, Geumgangkong, Sobaegnamulkong, Alchankong, Dajangkong, Pungsannamulkong, Daewonkong, Jangmikong, Tawonkong, Somyeongkong, Sodamkong, Songhagkong, Paldonamulkong, Sowonkong, Ilmikong, Saeolkong, Doremikong Daehwangkong Geomjeongkong1, Geomjeongkong2, Ilpumgeomjeongkong, Seonheukkong, Jinyulkong Jinpumkong, Jinpumkong Sinrokkong, Seonnogkong, Danmi, Dajin, Mirang, Danmi2, Nokwon, Sangwon, Cheongyeob Jangwonkong, Jinmi, Daepung, Hojang, Shingi, Daemang, Daol, Seonyu, Daemang2, Mansu, Hoban, Nampung, Daeyang, Daewang, Gangil, Cheonga, Daeha, Cheonsang, Socheong, Hanol, Geomjeong5, Soheuk, Manpoong, Jungmo3003 Sohokong, Seabyeolkong, Sorog, Anpyeong, Seonam, Dagi, Dachae, Sojin, Bosug, Sogang, Nogchae, Wonhwang, Jangki, Jonam, Pungwon, Wonkwang, Hoseo, Sinhwa, Shingang, Sohwang, Galchae, Jungmo3001, Sohyeon Cheongjakong, Geomjeongkong 3, Geomjeongkong 4, Cheongdu1, Cheongja2, Geomjeongsaeol, Cheongja3, Ilpumgeomjeong2, Heugmi, Daeheug, Heugseong, Jungmo3002 Introduction Korea landrace Uram, Saedanbaek, Hwangkeumol, Jungmo3006, Jungmo3007, Jungmo3004, Hybridization - Neulchan, Chamol, Sowon2010, Joyang1, Jungmo3009, Jungmo3011, Jungmo3008, Jinpung, Haepum, Wonheug, Haewon Cheongmiin, Socheongja Saegeum, Seonpung, Jungmo3010, Teaseon, Daechan, Daepung2, Duruol, Miso, Jungmo3005, Jangol Introduction

6 184 Plant Breed. Biotech (September) 3(3):179~196 Table 2. Summary of 178 Korean soybean varieties. Name Seed Color Breeding Growth Utilization protein oil Crude Crude Parents Year method Weight Seedcoaledon u) t) s) r) (cm)* Coty- Height type z) (Maternal/Paternal) released Size Shape Flower Hilum y) (g/100 x) w) v) (%)* (%)* seeds) Data q) 1 Jangdanbaekmok L Korea (Jangdan) 1913 M 25.2 G Y Y P W D S&T GBIC 2 Chungbukbaek L Korea (Chungbuk) 1948 M 22.7 G Y Y W Y D S&T GBIC 3 Iksan L Korea (Iksan) 1948 S 14.8 O Y Y P Br ID S&T GBIC 4 Buseok L Korea (Youngju) 1948 M 25.4 G Y Y P Y D S&T GBIC 5 Haman L Korea (Haman) 1960 M 20.8 G Y Y P Br D S&T GBIC 6 Keumgangdaelip L Korea (Anyang) 1960 M 23.6 NA Y Y P Y D S&T NA NA NA RDA Keumgangsorip L Korea 1960 SM 18.7 G Y Y P Y D S&T GBIC 8 Yukwoo 3 I Japan (Rikuu 3) 1960 M 16.1 NA Y Y P G D S&T NA NA 50 RDA Kwangdu L Korea (Jeonnam) 1966 M 20.6 G Y Y W Br D S&T GBIC 10 Hill I The USA (D / D ) 1967 S 14.4 NA Y Y W DBr NA BS NA NA NA RDA Shelby I The USA (Lincoln(2) / Richland) 1967 NA NA NA NA Y NA NA NA S&T NA GBIC 12 Kwangkyo B Jangdanbaekmok / Yukwoo 3 (Rikuu3) 1969 M 20 G Y Y P T D S&T GBIC 13 Bong-Eui B Lincoln / Yukwoo 3 (Rikuu 3) 1970 M 16.7 G C Y P LBr D S&T NA NA 51 RDA Eundaedu I Japan (Gin Daizu) 1970 M 24.2 NA V Y P Br NA S&T NA NA 58 RDA Kang-lim B Keumgangdaelip / Norin M 24 G Y Y W Bl D S&T RDA Dongpuk-tae I Japan (Raiden) 1974 NA NA NA Y Y P LBr D S&T NA NA NA RDA Baegcheon B Eunbaek (Ginjiro) / Dancheondamrok 1977 SM 19 NA Y G W Br D S&T NA RDA Danyeob I The USA (Essex, Lee / S ) 1978 S 12.7 G Y Y P G SD BS GBIC 19 Jangyeob B Miyagi Sirome / SS M 24 G Y Y P Y D S&T GBIC 20 Hwangkeum B SS7006 // Baekmokjangyeob 1980 M 25 G Y Y P Br D S&T GBIC 21 Jangbaeg B Suwon61 / SS M 15.4 G LY Y W Br SD S&T RDA Namcheon B Dongpuktae / Tachi Suzunari 1982 M 21.3 G Y Y P Br D S&T GBIC 23 Togyukong B SS74185 / Jangyeob 1983 SM 18 O Y Y P Br D S&T GBIC 24 Milyang B Kwangkyo / Williams 1983 M 19.9 NA Y Y W T ID S&T NA NA 92 RDA Baegun B Kwangkyo / dtl-long raceme 1984 M 21.1 G Y Y W Y D S&T GBIC 26 Pangsa B Mutant from CB S 9.9 G Y Y P Br D BS GBIC 27 Saeal B Kwangkyo / SS M 25 O Y Y P LY D S&T GBIC 28 Paldal B Elf / SS S 15 O Y Y P Bl D S&T GBIC 29 Pokwangkong B Jangyeob / PI M 25.4 NA Y Y P Y D S&T RDA Dankyeong B Kwangkyo / Willams 1986 SM 18.8 G Y Y W T D S&T GBIC 31 Eunha B D / Danyeob (Essex) 1986 S 11.6 G Y Y P Br D BS GBIC 32 Muhan B Hwangkeum / Wells 1988 SM 18.2 G Y Y P Br ID S&T GBIC 33 Namhae B Danyeob (Essex) / Hill 1988 SM 12.4 G Y Y W LY D BS GBIC 34 Jangkyongkong B Kwangkyo / Harcor 1988 M 22.9 O Y Y W LBr ID S&T GBIC 35 Jangsu B Elf / SS M 22.2 G Y Y P LBr ID S&T RDA Danweonkong B Willams / Suwon SM 18.2 G Y Y W T D S&T RDA Malli B Jangyeob / PI SM 18.9 G Y Y P Y D S&T GBIC 38 Sinpaldal B Will / SS SM 17.2 G Y Y W Br D S&T GBIC 39 Taekwang B SS77011 / Dongsan (Touzan) M 22.9 G Y Y W Y D S&T GBIC 40 Samnam B Suwon101 / YS M 21.2 NA Y Y W Br D S&T RDA Keunol B Korea (Chilgok) 1991 M 28.4 G Y Y W Y D V&E RDA Sinpaldal2 B Togyu / SS SM 19.5 G Y Y W Br D S&T NA NA 55 RDA Bukwang B Jangbaeg / Pangsa 1992 S 13.9 G Y Y W T D BS GBIC 44 Geomjeong1 B SS / Hwangkeum 1993 M 29 G Bl Y W Bl D CR RDA Danbeakkong B Dongsan (Touzan) 69 / D SM 13.9 G Y Y P Br D S&T GBIC 46 Kwangan B Dongsan (Touzan) 69 / Hwangkeum 1993 S 11.4 NA Y Y P Bl D BS 44.7 NA 92 RDA Pureun B Cheongsaeknamul / L M 20.1 NA G Y W Bl D BS NA NA NA RDA Hwaeomput I Japan (Kegon) 1993 M 27.2 G Y Y W G D V&E RDA 2008

7 Soybean [Glycine max (L.) Merrill]: Importance as A Crop and Pedigree Reconstruction of Korean Varieties Duyou B Milyang18 / Bonghwajaerae 1993 NA NA NA Y Y W T D S&T RDA Hwasongputkong L Korea (Yongin) 1993 NA NA NA Y Y W Br D V&E RDA Soyang B SS79149 / L NA NA NA Y Y W Br NA S&T NA NA NA RDA Seokryangput I Japan (Yusuzumit) 1994 L 37 G LG Y W Br D V&E NA NA 24 GBIC 53 Jinpum I Japan 1994 NA NA G Y Y P Y D S&T NA RDA Hannam B YS236 / SS S 11 G Y Y P Y SD BS NA NA NA RDA Myeongjunamul B Jangyeob / Baegun 1995 S 11.4 G Y Y P LBr D BS RDA Iksannamul B Danyeob (Essex) / Hill 1995 S 12.6 G Y Y W LBr D BS NA NA 76 RDA Geumgangkong B YS267 / YS SM 18.8 G Y Y W G D S&T RDA Sobaegnamul B Milyang18 / Bonghwajaerae 1995 S 11 G Y Y P Y D BS NA NA 47 RDA Alchan B Hwangkeum / Eunha 1996 S 14.6 NA Y Y P LBr D S&T RDA Dajang B YS23-2B / Paldal 1996 SM 19.9 G Y Y W G D S&T Shin et al Pungsannamul B Pangsa / KLS S 11.3 G Y Y P Y D BS RDA Jinpum 2 I Japan 1996 M 21.9 G Y Y P Y NA S&T RDA Geomjeong2 B SS83021 / SS M 28.3 G Bl Y P Bl D CR RDA Geomjeongol L Korea 1996 M 22.4 G Bl Y P Bl D V&E RDA Daewon B Suwon133 / Milyang L 24.6 G Y Y W Y D S&T GBIC 66 Jangmi B YS110-2B-3-1 / SLSB SM 19.3 O Y Y P Y D S&T NA NA 63 RDA Ilpumgeomjeong B SLSB87-3 / YS M 27.6 G Bl Y P Bl D CR RDA Tawon B Paldal / ES ES 9.2 G Bl Y P Bl D BS RDA Somyeong B Eunha / Pangsa 1998 ES 8.3 NA Y Y P LBr D BS NA NA NA RDA Paldonamul B KW / Hill 1998 S 11.8 NA Y Y P Br D BS 39.1 NA 57 RDA Sodam B SNUA78010 / Dongsan (Touzan) M 25.2 G Y Y P Y D S&T RDA Seonheuk B Hwangkeum / Sinnongheuk (Sinano Kuro) 1998 L 34.2 NA Bl Y P Bl D CR 40.1 NA NA RDA songhagkong B Dongsan (Touzan) 74 / Jangbaeg 1998 M 20.9 G Y Y W Y D S&T RDA Ilmi B YS536 / Paldal 1998 M 20.2 G Y Y P Br SD S&T RDA Saeol B YS841 / Baeksajajidu (Shirojishi) 1998 M 27.2 S Y Y W Y D S&T RDA Sowon B Eunha / Pangsa 1999 ES 9.3 NA Y Y P LBr D BS NA NA NA Park et al Doremi B Namhae / YS S 11 G Y Y W DBr D BS NA RDA Daehwang B Keunol / SLSB L 31.9 S Y Y W Y D S&T NA NA NA Baek et al. 2001a 79 Jinyul B Hwangkeum / Sinnongheuk (Sinano Kuro) 1999 M 28.3 NA Br Y P Br D CR Yun et al Heugcheongkong B Korea (Yeongwol) 1999 L 30.6 S Bl G P NA D CR RDA Galmi B Korea (Gwangju) 1999 M 27.2 NA Br Y P Br D CR RDA Jangwon B Pokwang / SS M 26.9 G Y Y P Y D S&T RDA Sinrokkong B Suwon163 (Mikawashima) / Jinpum ML 29.5 G Y Y P Y D V&E NA NA 38 RDA Seonnogkong B Keunol / Vegetable soybean form Japan 2000 L 30.9 S LG Y W T D V&E RDA Soho B Namhae / YS SM 19.6 G Y Y W LBr D BS RDA Saebyeol B Bukwang / Namhae 2000 S 12.9 G Y Y P DBr D BS RDA Cheongja B Milyang55 / Geomjeong M 28.8 O Bl G P Bl D CR Baek et al. 2001b 88 Jinmi B HS12 / Manli 2001 M 23 G Y Y P Y D S&T RDA Sorog B Pureun / Namhae 2001 S 11.9 G LG Y P Br D BS GBIC 90 Geomjeong3 B Sinnongheuk (Sinano Kuro) / SNUA L 31 S Bl Y P Bl D CR RDA Geomjeong4 B YS823 / YCS M 28 O Bl Y P Bl D CR RDA Anpyeong B Eunha / SS S 11.6 G Y Y P Y D BS NA NA 64 Yun et al. 2005b 93 Seonam B Kosuzu / Bukwang 2002 ES 9 G Y Y P Br D BS RDA Dagi B Namhae / D S 11.4 G Y Y P Br D BS RDA Dachae B Hannam / Eunha 2002 ES 8.6 G Y Y P LBr D BS Shin et al Daepung B Baegun / Sinpaldal M 20.7 G Y Y W LBr D S&T Park et al. 2005

8 186 Plant Breed. Biotech (September) 3(3):179~ Hojang B HS309 / Suwon M 21.6 G Y Y W Y D S&T RDA Daol B Keunol / YS L 33.6 G Y Y W LBr D S&T Danmi B Milyang37 / Josaengbaegjo (Wase Hakucho) 2002 L 31.3 G LG Y W Y D V&E Baek et al Kang et al Shingi B Baegun / Sinpaldal M 22.5 G Y Y P LBr D S&T 38.5 NA 73 RDA Daemang B Jangyeob / Seokryangput (Yusuzumit) 2003 L 31.4 G LG Y W Br D S&T 39 NA 44 Kim et al Sojin B Danyeob (Essex) / SI ES 9.7 G Y Y P LBr D BS RDA Bosug B Namhae / Camp 2003 ES 8.6 G Y Y P Br SD BS RDA Cheongdu1 B SI93006 / Sinpaldal M 24.5 G G G W Bl D CR Yun et al. 2005a 105 Cheongja2 B Milyang70 / Ilpumgeomjeong 2003 M 26 O Bl G P Bl D CR RDA Dajin B YS1040 / Keunol 2003 M 20.7 NA G Y W Y D V&E NA NA NA RDA Seonyu B Suwon162 / YS ML 29.6 G Y Y P Y D S&T RDA Sokang B Namhae / Camp 2004 ES 9.5 G Y Y W Y D BS RDA Nogchae B Pureun / Milyang ES 9.1 G G G W Y D BS NA NA 41 RDA Geomjeongsaeol B Keunol / Geumjeongol 2004 L 31.1 G Bl Y P Bl D CR Baek et al Cheongja3 B Suwon174 / Mokpo L 32.1 S Bl G P Bl D CR RDA Daemang2 B Sinpaldal2 / Seokryangput (Yusuzumit) 2005 M 25.3 S LG Y W G D S&T NA NA NA Yun et al Wonhwang B Camp / Myeongjunamul 2005 S 10 G Y Y P LBr D BS RDA Jangki B Eunha / MS S 11.9 G Y Y P LBr D BS NA NA NA Oh et al Ilpumgeomjeong2 B Milyang68 / Suwon M 25 G Bl Y P Bl D CR RDA Mirang B Keunol / Geumjeongol 2005 M 25.4 G Bl Y W Bl D V&E Baek et al Danmi2 B Seokryangput(Yusuzumit) / YS L 30.6 G LG Y W G D V&E RDA Mansu B Suwon192 / Suwon M 26.5 G LG Y P Y D S&T RDA Hoban B GWS91 / Jinpum 2006 ML 29 S Y Y P Y D S&T RDA Jonam B Eunha / Jeonju NA NA NA Y Y NA NA NA BS NA NA NA Oh et al Pungwon B SI93001 / Suwon S 10.9 NA Y Y NA NA D BS RDA Heugmi B Milyang78 / Milyang M 24.8 G Bl G P NA D CR RDA Socheong B Milyang78 / Peking 2006 SM 15.7 PS Bl G W Bl D S&T Baek et al Nokwon B Keunol / Hyangnam L 30.6 G LG Y W Br D V&E Ko et al Nampung B Suwon190 / Bogwang 2007 SM 19.9 G Y Y W Br D S&T Kim et al. 2010b 126 Daeyang B Suwon192 / SS M 25.2 G Y Y P Y D S&T Kim et al. 2010a 127 Wongwang B Danyeob (Essex) / MS S 10.9 G Y Y P LBr D BS Oh et al Hoseo B Camp / Nattosan 2007 ES 7.4 G Y Y P LBr D BS RDA Sinhwa B Sowon * 4 / PI S 12.1 NA Y Y NA NA D BS RDA Daeheug B Daehwang / Milyang L 34.3 S Bl Y P Bl D CR RDA Sangwon B Keunol / Oshimamidori 2007 NA NA NA Y Y NA Y NA V&E RDA Daewang B GWS91 / Seokryangput (Yusuzumit) 2007 L 33.6 G Y Y P Y D S&T Choi et al Gangil B Suwon191 / Suwon M 23.3 G Y Y P NA D S&T KSVS 134 Cheonga B Sinpaldal2 / SS M 25.2 G Y Y W Y D S&T Ha et al Daeha 1 B Suwon192 / SS M 25.4 G Y Y W Y D S&T Baek et al. 2013a 136 Cheonsang B Suwon190 / Hwangkeum 2008 M 24.8 G Y Y W Y D S&T Kim et al Shingang B Sowon * 4 / L S 11 G Y Y P LBr D BS RDA Sohwang B Pungsannamul / HS ES 8.5 G Y Y P Y D BS RDA Galchae B YS1287 / Jinju ES 8.4 G Br Y P Br D BS Heugseong B Gnome 85 / Cheongja 2008 ML 29.2 PS Bl Y P Bl D CR Oh et al. 2009b Han et al. 2010

9 Soybean [Glycine max (L.) Merrill]: Importance as A Crop and Pedigree Reconstruction of Korean Varieties Jungmo3001 B Jinju1 / PI NA NA NA Bl Y NA NA NA BS NA NA NA KSVS 142 Jungmo3002 B Tawon / Jinju NA NA NA Bl Y NA NA NA CR NA NA NA KSVS 143 Hanol B 144 Sohyeon B SS91408 / Hwaeomput (Kegon) Wonheug / Cheongyeob 1 / Joyang M 26.4 G Y Y W Y D S&T RDA ES 8.8 NA Bl Y NA NA D BS NA NA NA RDA Geomjeong5 B Sinpaldal2 / Geomjeong M 23.2 G Bl Y P Bl D S&T Han et al Soheuk B Milyang78 / Peking 2009 S 12.2 PS Bl G W Bl D S&T RDA Cheongyeob B Ilpumgeomjeong / Daehwang 2009 L 35.8 G Bl Y W Bl D V&E Han et al Jungmo3003 B Suwon191 / Milyang NA NA S Y Y P Br D S&T NA NA NA KSVS 149 Manpoong B 150 Uram B Dongsan (Touzan) 121 / Sprite87 Suwon190 // Sinpaldal2 / T M 29.5 S Y Y W Y D S&T Yi et al M 25.8 G Y Y W Y D S&T RDA Saedanbaek B MD87L / SS M 20.7 G Y Y W LBr D S&T RDA Hwangkeumol B SS92414 / Hwaeomput (Kegon) 2010 M 28.6 G Y Y W Y D S&T RDA Sowon2010 B Sowon * 4 / L S 11.7 G Y Y P LBr D BS RDA Joyang B Pungsannamul / Suwon S 11.6 G Y Y P Y D BS Kim et al Jungmo3006 B Hwangkeum * 4 / V M 24.9 NA NA Y NA NA NA S&T NA NA 95 GBIC 156 Jungmo3007 B Taekwang * 4 / V M 24.9 NA NA Y NA NA NA S&T NA NA 85 GBIC 157 Jungmo3004 B Iksan21 / Milyang L NA S Y Y W Y D S&T NA NA NA KSVS 158 Jungmo3005 B Cheongja / Geomjeong L NA G G Y W Y D S&T NA NA NA KSVS 159 Wonheug B YS1286B / Jinju ES 8.8 G Bl Y P Bl D BS KSVS 160 Neulchan B SS / SS M 21.7 G Y Y W Y D S&T NICS 161 Chamol B Sinpaldal2 / Keunol 2011 M 27.7 G Y Y W Y D S&T NICS 162 jungmo3008ho B Hwangkeum / SS L 36.5 G Y Y P Y D S&T NICS 163 jungmo3009ho B Milyang121 / Daemang 2012 ML 29.3 G Bl G W NA D CR NICS 164 Jinpung B Daepung / SS M 23 G Y Y P Y D S&T NICS 165 Haepum B Bosug / Suwon S 10.4 G Y Y W LBr D BS NICS 166 Saegeum B Daepung / SS SSD ML 25.4 G Y Y W Y D S&T NICS 167 Seonpung B Suwon224 / YS1325-3S L 25.9 G Y Y W Y D S&T NICS 168 Jangol B SI (Janghak5) / Suwon SM 18.9 G Y Y W Y D S&T NICS 169 jungmo3010ho B SI / SI0001 (Ziong pin ) 2013 SM 17.1 G Y Y P Y D S&T NICS 170 Jungmo3011ho B Cheongja3 / Danpaheukdu (Tanba Kuro) 2013 EL 66.4 G Bl Y P Bl D CR NICS 171 Cheongmiin B Cheongja / Daemang 2013 L 34.3 G G G W Bl D CR NICS 172 Taeseon B Shingi / Taekwang 2013 M 22.2 G Y Y P Y D S&T NICS 173 Daechan B Suwon224 / YS L 24.5 G Y Y W Y D S&T KSVS 174 Daepung2 B Daepung / SS M 20.9 G Y Y W Y D S&T NICS 175 Duruol B Hwaeomput (Kegon) / Suwon L 27.7 G Y Y W LBr D S&T NICS 176 Miso B Daemang / Jinpum L 28.2 G Y Y W Y D S&T NICS 177 Socheongja B Suwon214 / YCL S 12 G Bl G W Bl D CR NICS 178 Haewon B Bosug / Somyeong 2014 ES 8.1 G Y Y P LBr D BS NICS z) L: Landrace, I: Introduced, B: Bred y) EL: Extra Large, L: large, ML: Medium to large, M: Medium, SM: Small to medium, S: Small, ES: Extra small, NA: Not available x) G: Globular, O: Oval, S: Spheroid, PS: Prolate Spheroid, NA: Not availabl w) Y: Yellow, Bl: Black, Br: Brown, G: Green, LY: Light yellow, LG: Light green, NA: Not available v) Y: Yellow, G: Green u) P: Purple, W: White, NA: Not available t) W: White, Y: Yellow, Br: Brown, G: Gray, T: Taupe, Bl: Black, DBr: Deep brown, LBr: Light brown, LY: Light Yellow, NA: Not available s) D: Determinate, ID: Indeterminate, SD: Semi-determinate, NA: Not available r) S&T: Soy sauce & Tofu, BS: Bean sprout, V&E: Vegetable & early maturity, CR: Cooking with rice q) GBIC: RDA-Genebank Information Center, KSVS: Korea Seed & Variety Service, NICS: National Institute of Crop Science, RDA 2008: Bibliography of soybean varieties (in Korean), RDA 2010: 2010 Commentary of major field crops (in Korea), RDA 2011: 2011 Commentary of major field crops II (in Korea), RDA 2012: 2012 Commentary of field crops (in Korean) *NA: Not available

10 188 Plant Breed. Biotech (September) 3(3):179~196 Integration and reconstruction of soybean pedigree Starting from Jangdanbaekmok the first cultivar registered in 1913 till now, we attempted to reconstruct a fully integrated pedigree including all the 178 varieties currently recorded in Korea. Thereby, it has ended up with a total of four pedigrees (Fig. 2). Of 178 registered cultivars, 10 varieties (5.6%) could not be integrated into any pedigrees because they lacked information on which they were employed as elite parental lines to cross. They include Chungbukbaek (1948), Iksan (1948), Haman (1960), Keumgangsorip (1960), Buseok (1948), Heugcheongkong (1999), Galmikong (1999), which were derived from Korean landraces, and introduced accessions, such as Shelby (1967), Eundaedu (1970), Hwasongputkong (1993). Of 168 varieties included in the pedigree network, 136 varieties (76.4%) and 32 varieties were involved in one or two pedigrees, respectively. As seen in the Pedigree I (Fig. 2A), Kwangkyo, Hwangkeumkong, Paldalkong and Sinpaldalkong 2 (Kim et al. 1994) served as central crossing parents, which is the largest among four pedigrees and resulted from the integration of three previously reported pedigrees (Jong et al. 2006), Cluster 7 ( Kwangkyo group), Cluster 8 ( Hwangkeumkong group), Cluster 9 ( Paldal group). This pedigree contains 85 hybridization-bred varieties, 49 breeding lines, 7 landraces and 24 introduced varieties (Fig. 2A). Nodal breeding points of this pedigree start with Jangdanbaekmok (the first landrace-derived cultivar), Kwangkyo (the first hybridization bred variety) and three Japan-introduced accessions such as Yukwoo3, Baekmokjangyeob, Dongpuk-tae. Kwangkyo was intensively employed as parental line Fig. 2. Reconstructed pedigrees of Korean soybean varieties. The pedigrees consist of a total of 168 registered Korean soybean cultivars. Some of registered cultivars originated from landraces after selection processes for line purification. Information implicated in shape, line and color, is denoted in the figure legends. A. Pedigree I. This pedigree contains a total of 174 nodes, which is composed of 24 introduced lines, 49 breeding lines, 7 landraces and 84 hybridization-bred varieties. In this pedigree, Kwangkyo, Hwangkeum, Paldal and Sinpaldal2 are the major crossing parents.

11 Soybean [Glycine max (L.) Merrill]: Importance as A Crop and Pedigree Reconstruction of Korean Varieties 189 Fig. 2. Continuously. B. Pedigree II. It is consists of 122 nodes, containing 26 introduced lines, 33 breeding lines, 1 landrace and 61 bred varieties. Central crossing parents involve Jangyeob, Baegun, Kwnagkyo, Keunol. C. Pedigree III. This pedigree is composed of 90 nodes, which contains 15 introduced lines, 23 breeding lines, 2 landraces and 47 improved varieties. Three parents, Pangsa, Eunha and Danyeob, played the most central roles in hybridization-based breeding.

12 190 Plant Breed. Biotech (September) 3(3):179~196 Fig. 2. Continuously. D. Pedigree IV. This one is an orphan pedigree that could not be connected to any other major pedigrees. The pedigree contains 6 introduced line, 12 breeding line, 3 landraces and 11 bred varieties. to breed other useful progenitors such as Hwangkeumkong (1980), Milyangkong (1983), Baegunkong (1984), Saealkong (Shin et al. 1985), Dankyeongkong (1986), Jangkyongkong (1988). Of Kwangkyo -derived progeny, Hwangkeumkong and Paldalkong were recognized by their superior traits and frequently used as parental line. For one example, Hwangkeumkong was developed by using USA-introduced Clark63 as the parental line and another introduced line Baekmokjangyeob (SMV-resistant) as maternal line, and thereby resulted in a combined trait of SMV resistance as well as large seed size (RDA 2012a). Likewise, Hwangkeum was employed as crossing parents to develop following varieties; Muhankong (1988), Geomjeongkong 1 (1993), Kwangankong (1993), Alchankong (Kim et al. 1997), Seonheukkong (1998), Jinyulkong (Yun et al. 2000), Hojang (2002), Cheonsang (Kim et al. 2012). Paldalkong was bred using USAintroduced Elf and a Kwangkyo -derived breeding line SS Paldal is highly tolerant not only to the lodging but also to major biotic stresses with small-tomedium seed size (RDA 2008a), and was employed to develop following varieties; Sinpaldalkong (1991), Sinpaldalkong 2 (1992), Dajangkong (Shin et al. 1997), Tawonkong (Kim et al. 1996), Ilmikong (Shin et al. 1998), Saeolkong (Baek et al. 1998), Geomjeong4 (2001). Sinpaldalkong 2, which occupies a significant part of the Pedigree I and is strongly resistant to soybean mosaic viruses, was developed by employing Togyu as maternal line and Paldal -derived breeding line SS79186 as paternal line. It bears medium-sized seeds and is known as tolerant or resistant to many diseases such as soybean mosaic virus, purpura, downy mildew and necrosis. Thereafter, Sinpaldal2 was used as breeding parent to develop following varieties; Daepung (Park et al. 2005), Shingi (2003), Cheongdu1 (Yun et al. 2005a), Daemang #2 (Yun et al. 2006), Cheonga (Ha et al. 2013), Geomjeong5 (Han et al. 2013), Uram (2010), Chamol (2011). One of Sinpaldal2 -derived progeny Daepung was bred using Baegun as maternal line and its yield was 305 Kg/10a, which was 20% higher compared to Taekwangkong. Daepung was further improved towards higher yield, and resulted in Daepung2ho, which is currently a cultivar of the highest yield (345 Kg/10a) in Korea. This cultivar is also tolerant to lodging, fire blight and seed shattering. Uram is another high yield cultivar (327 Kg/10a), and has merits of suitability to mechanized farming and fire blight resistance (RDA 2011). Pedigree II (Fig. 2B) shows that Baegunkong, Jangyeobkong and Keunolkong take central positions as basic parental lines, which comprises three pre-existing clusters 3 ( Dongpuk-tae group), 5 ( Jangyeob group) and 7 ( Kwangkyo group) (Jong et al. 2000). This pedigree harbors 61 hybridization-bred varieties, 33 breeding lines, 1 landrace and 26 introduced varieties. Baegun was developed using Kwangkyo as maternal line and the USA-introduced Dt1-long receme as paternal line, and has following characteristic traits; resistance to mosaic viruses, susceptibility to necrosis viruses and cyst nematodes, tolerance against lodging with medium height

13 Soybean [Glycine max (L.) Merrill]: Importance as A Crop and Pedigree Reconstruction of Korean Varieties 191 of 70 cm on average. Taekwangkong (1991), Myeongjunamulkong (1995), Daepung (2002) and Shingi (2003) were developed using this cultivar as parental line. Of these, Taekwangkong is known to have resistance against causal insect agents of mummification, brown spot and leaf spot, and can also tolerate soybean mosaic virus and microbe-derived brown spot (RDA 2012b). Jangyeobkong was bred by crossing Japan-introduced Miyagi Sirome with SS7023 derived from between Kwangdu and Baekmokjangyeob. The height of this variety is approximately 50 cm with medium-to-large seed sizes. Jangyeobkong has contributed to developing following varieties; Deokyu (1983), Mallikong (1990), Myeongjunamulkong (1995), Hojang (2002), Daemang (Kim et al. 2005), Daeyang (Kim et al. 2010a), Daeha (Baek et al. 2013a). Keunolkong was originated by selecting pure lines collected in Chilgok Kyungbuk in 1986, which bears large seeds with high yield. It belongs to short stem type with 37 cm average height and is very strong against the lodging. This variety was reported to have resistance to mosaic/necrosis viruses, downy mildew and anthracnose (RDA 2008b). Following varieties, which were bred using Keunolkong as crossing parent, are involved; Saeolkong 1998), Daehwangkong (Baek et al. 2001a), Seonnogkong (2000). Daol (2002), Dajin (Oh et al. 2004), Geomjeongsaeol (Baek et al. 2005), Mirang (Baek et al. 2006), Nokwon (Ko et al. 2008), Sangwon (2007), Chamol (2011). Pedigree III was constructed by extending previous cluster 4 ( Pangsa group) and cluster 6 ( Danyeobkong, Hill group) (Jong et al. 2000). This pedigree is composed of 47 crossing/mutation-bred varieties, 23 breeding lines, 2 landraces and 15 introduced varieties, in which Danyeobkong, Pangsakong (Hong et al. 1985) and Eunhakong take major parts as the parental lines (Fig. 2C). Pangsakong is the first mutation-derived variety developed by treating the USA-introduced CB27 with gamma ray. This variety has a suitable property for bean sprout due to its uniformly small seed size. Pangsa possesses a high necrosis resistance, whereas it shows a medium level resistance to the soybean mosaic viruses. Danyeobkong was actually introduced from the USA in the name of Essex, which was developed using salinity-tolerant variety Lee as the maternal line, and registered as Korean cultivar in 1978 (Table 1). Like Pangsakong, Danyeobkong belongs to small seed type, resists necrosis/mosaic viruses, and is strong against the lodging with stable yield patterns. Eunha (1986), Namhaekong (Shin et al. 1989), Iksannamul (1995) and Wongwang (Oh et al. 2009) have derived from Danyeobkong using as crossing parent. Of these, Eunhakong was developed by employing the USAintroduced D as maternal line with an aim to make a new sprout cultivar. This cultivar has suitable features, i.e., small seeded with high yield, for the bean sprout, and is known to show resistance to necrosis, root rot, downy mildew and purpura, whereas it is weak to mosaic viruses. Owing to these qualities, Eunha has frequently been employed to develop other useful varieties such as Alchankong (1996), Somyeongkong (1998), Sowonkong (Park et al. 2000), Anpyeong (Yun et al. 2005b), Dachae (Shin et al. 2003), Jangki (Oh et al. 2006), and Jonam (Oh et al. 2007). Pedigree IV is a kind of orphan ones, because most varieties lack information available for breeding pathways (Fig. 2D). Actually it consist of three small pedigrees containing 6 introduced variety, 11 Korea-bred varieties, 12 breeding lines and 3 landraces. Except for Jungmo3004 and jungmo2010ho, other major varieties in the pedigree including Ilpumgeomjeong2 (2005), Heugmi (2006), Socheong (Baek et al. 2000) and Soheuk (2009) are all black-seeded and developed in relatively recent years with favorable traits. For example, Ilpumgeomjeong2 has a varietal property of medium-to-large seed, short stem, stress tolerance with high yield, and its average height is 49 cm, which offers a desirable strength against the lodging, high moisture content/rainfall and drought. This cultivar is also popular for cooking-with-rice due to its color and sweetness (RDA 2006). Socheong and Soheuk were bred using Milyang78, which derived from collected black soybean landrace, as the maternal line and Peking (small seeded and lodging-resistant) as paternal line. Socheong is 62 cm in its height, bears relatively more pods, and is very strong against the lodging. Soheuk is a black seeded variety with green cotyledon, and was developed to replace a popular landrace Jwinunikong. This variety has been further improved, compared to

14 192 Plant Breed. Biotech (September) 3(3):179~196 pre-existing small-seeded black soybean varieties, for higher absorption rate of moisture, and for larger pod numbers per hill (Baek et al. 2013b). CONCLUSION Pedigree for crops is truly essential to effectively manage breeding programs, and may provide breeders with pivotal information for selection of parental lines and design of crossing strategies. In this review, we intended not only to integrate all available information on currently registered Korean soybean varieties, but also to reconstruct an entire breadth of their pedigree. Such an attempt has resulted in a total of four pedigrees (Fig. 2), which is a lot more extended compared to the latest pedigree analyses (Jong et al. 2006). Out of 178 soybean varieties officially recorded at the GBIC and the KSVS, a total of 168 (94.4%) cultivars could be connected within the context of pedigrees. These pedigrees were reconstructed almost purely based on publically available information accessible to literatures and public databases. Soybean has long been cultivated for major source of protein and oil in the human history. In more recent years, it is becoming more important as a source of well-being for mankind in terms of medicinal use as well as food. Additionally its unique biological property of symbiotic nitrogen fixation is beneficial to enrich the soil, thereby protecting environment and enabling sustainable agricultural practice. Another benefit of soybean on human health has been widely explored during the last two decades (Ali 2010). Thanks to its wide range of beneficial aspects, it is likely that the cultivation and breeding of soybean will be increasingly promoted in the future. In recent years, we are facing a transition stage in breeding technologies, from conventional (phenotype-first) breeding to genomics-driven (genomic information-based design) molecular breeding. Genome-wide understanding and its application to breeding are being significantly facilitated by cutting edge NGS technologies in conjunction with high throughput bioinformatic analyses. Such situation may lead to opening of a new phase of molecular breeding in the near future, so called breeding-by-design. In parallel with technological advancement, well-organized crop resources and information will become more and more important. In summary, as crop pedigree is one of the most important information for breeding, we anticipate that the pedigree rebuilt in this study will play a constructive role in breeding a diverse array of new soybean varieties with desirable traits when it is synergized with new findings and knowledge driven by ever advancing technologies and omics -based bioinformatic tools. ACKNOWLEDGEMENTS This study was supported by a grant from the Next- Generation BioGreen21 Program (PJ011182), Rural Development Administration and partly by a grant from the KRIBB Research Initiative Program, Republic of Korea. REFERENCES Ali N The origin and history of soybean. pp In: The soybean: botany production and uses. CABI Press, Cambridge, MA. Baek IY, Shin DC, Kang ST, Song SB, Choung MG, Kwack YH, Kim SC. 2001a. A Larger Seed Size, Geed Seed Quality and High Yielding Soybean New Variety Daehwangkong. Korean J. Breed. Sci. 33: Baek IY, Kang ST, Shin DC, Choung MK, Han WY, Kwack YH, Moon HP. 2001b. A New Black Soybean Variety with Green Cotyledon Early Maturity and Large Seed Size Cheongjakong. Korean J. Breed. Sci. 33: Baek IY, Kang ST, Oh SK, Han WY, Choung MG, Shin DC, Kim SD, Kim SC A New Soybean Cultivar for Tofu and Soy Sauce with Large Seed, Early Maturity and Good Seed Quality Daol. Korean J. Breed. Sci. 35: Baek IY, Kim HT, Ko JM, Han WY, Park KY, Oh KW, Ha TJ, Shin SO, Yun HT, Moon JK, Oh YJ, Kim SL, Seo MJ, Lee JH, Choi JK, Kim JH, Lee SS, Son CK, Kang DS, Kim ST. 2013a. A New Soy-paste Soybean Cultivar, Daeha 1 with Disease Resistance, Lodging Tolerance and High Yielding. Korean J. Breed. Sci. 45: Baek IY, Han WY, Ko JM, Kim HT, Jeon MG, Park KY, Lee