Black soybean teata is helpful to preventing obesity through enhancing energy expenditure and suppressing accumulation in mesenteric adipose tissue. The ethanol testa-extract of Cheongja #3 black soybean (ETCBS) is also have similar effects on obesity. So far, it is not clear whether the ethanol testa extract of black soybean can have effect on the characters of subcutaneous adipose stem cells such as proliferation, activity, and adipogenicity. The doubling time was different between subcutaneous adipose-derived stem (ADS) and visceral ADS cells. By the in vitro culture and passage, the doubling time was increased both of them. The shape was not different between groups and their passages were not cause the change of shapes. In the case of visceral ADS cells, the doubling time was 62.3 h or 40.3 h in control or high fat diet administrated mice, respectively, but not modified in subcutaneous ADS cells. ETCBS administration caused of increased the doubling time from 62.3 h to 84.2 h. ETCBS had suppressive effects on the cellular activity of subcutaneous ADS cells. The intensity of Oil Red O staining was very faint in 100 and 200 mg/mL ETCBS treated groups. The amounts of accumulated triglyceride were also significantly low in 100 and 200 mg/mL treated groups. From these results we know that the doubling times and the effects of ETCBS are different by the anatomical origin of ADS cells. It also suggested that ETCBS may suppress the differentiation of subcutaneous ADS cells into the precursors and maturing of adipocytes.

The purpose of this study was to estimate the growth promoting effects and improvement of antioxidant activity of the soybean sprouts treated with Chlorella sp. culture solution. The soybean sprout treated with 0.1% and 0.2% Chlorella sp. culture solution was significantly increased the length (more than 43.0%), the thickness (more than 0.5~0.7 mm), fresh weight (more than 2.9~3.7 g) compared to non-treated control in vitro. In organic soybean sprouts farm, the 0.2% chlorella culture solution applied to mass culture of soybean sprout and the fresh weight of soybean sprouts increased by more than 25% and the yield was very high as 598.33% compared to untreated control. In addition of sensory test, there is no fishy odor and better crunchy texture and nutty flavor for the treatment soybean sprouts compared to untreated soybean sprouts. Particularly, free-radical scavenging activity (DPPH) and superoxide dismutase activity (SOD) of the soybean sprouts were significantly increased more than 26.1% and 40.4%, respectively by treated with 0.1% and 0.2% Chlorella culture solution. Consequently, the treatment of chlorella culture solution to grow soybean sprouts is also promoting quality and antioxidant activity as well as promoting the growth of sprouts. Therefore, chlorella is considered to be worth as functional materials for high-quality sprouts grown.

‘연풍’은 1999년에 대립이며 황색 종피이며 다수성인 ‘수 원191호’를 모본으로 하고 경장이 짧고 조생종인‘수원196호’ 를 부본으로 교배되었다. 2000년도에 F1을 양성하고, 2001년 도에 F2는 집단선발을, 2002년 ~ 2004년도에 F3 ~ F5세대를 계통육종법으로 선발한 HS982-B-1-1-2-2 계통으로 계통명은 ‘연천3호’이다. ‘연풍’의 주요특성을 요약하면 다음과 같다. 신육형은 유한신육형이며 꽃색은 자색이고, 엽형은 피침형 과 능형의 중간형이며, 모용색은 회색이고, 종실모양은 편구 형이며, 제색과 종피색은 황색이고 협색은 갈색이고 협은 성 숙 후에도 잘 개열되지 않으며, 성숙기는 대원콩보다 15일 빠 른 조중생종이며, 100립중은 28.7 g으로 대립이다. SMV유묘 검정에서는 하위엽에서 모자이크증상을 보였으나, 포장에서 는 0이었다. 검은뿌리썩음병의 발병율은 2.5%였다. 불마름병 유묘 검정에서는 5 정도였으나, 포장에서는 0이었다. 콩나방 은 1.5%였다. 종실의 화학적 성분은 단백질은 36.1%이었는 데 특히 아미노산 함량은 346.8 ㎎/100g, 아이소플라본 함량 은 1,667 ㎍/g으로 대원콩보다 낮았다. 조지방은 19.2%였는 데, 대원콩보다 포화 지방산은 11.8%로 1.6% 높았으나, 불포 화지방산은 85.0%로 1.2% 낮았다. 가공적성에서 두부수률은 대원콩과 비슷한 수준이었으나 두부물리성 중 경도, 검성, 응집성은 비슷한 수준이었으나 경도는 낮았다. 청국장의 발효 및 풍취는 대원콩보다 우수하였다. 수량성은 대비품종인 대원콩보다 생산력검시험에서는 16% 증 수 되었고, 3개년 간 실시한 지역적응시험에서 3.44 MT/ha으 로 38% 증가하였다(품종보호번호: 제4242호).

Soybean is one of the important food crop around the world. Especially in East Asia, it is the main ingredient for traditional food like soy sauce and soy paste. The double cropping system including soybean following onion, Chinese cabbage, and potato is widely adopted in Southern region of Korea. In this system, sowing date of second crop (soybean) can be delayed depending on first crops’ growth period and weather condition. When planting date is delayed it is known that soybean yield is declined because of shorter vegetative growth period and earlier flowering induced by warm temperature and changes in photoperiod. The objective of this study was to determine soybean growth and yield responses as plant populations at late planting date. Field experiment was conducted at Department of Functional Crop, National Institute of Crop Science, RDA located in Miryang, Gyeongsangnam-Do for two years (‘13-’14) in upland field with mid-late maturity cultivar Daewon. A split-plot block design was used with three replications. Main plots were three sowing dates from June 20 to July 20 with 15 days intervals, and subplots were 4 levels of planting densities. Data of maturity (R8) was recorded, yield components and yield were examined after harvesting. Experimental data were analyzed by using PROC GLM, and DMRT were used for mean comparison. Optimum planting population for maximizing soybean yield in late planting which compared with standard population. In mid-June planting, higher planting density causes increased plant height and decreased diameter which lead to higher risk of lodging, however, reduced growth period due to late planting alleviated this problem. Therefore higher seeding rates can provide protection against low seedling emergence caused by late planting in this region.

There has been known C3G (Cyanidin-3- Glucoside), D3G (Delphinidin-3-Glucoside), and Pt3G (Petunidin- 3-Glucoside) were main anthocyanin pigments in black-seeded soybean. Anthocyanin contents of total 1,032 black-seeded soybean germplasms were analyzed by HPLC. Average of total anthocyanin content was 11.67 mg/g on the all materials ranged from 0.54 to 23.45 mg/g. Mean value of C3G, D3G, and Pt3G contents in all black-seeded soybeans were 8.81, 1.78 and 0.79 mg/g, respectively. Environmental conditions influenced anthocyanin contents during seed development. Delayed flowering, especially of later maturing germplasms, has been showed to result in increased anthocyanin content. So, prolonged maturation period germplasm is generally higher than that of shorten genotypes. It may be concluded that the higher levels of anthocyanin content was associated with the late dates of harvest maturity. Also larger seeds showed high anthocyanin contents than smaller. That inclination is similar in C3G’s occasion because C3G content contribute highly to total anthocyanin content than other pigments.

한국자원 128개와 중국자원 214개 및 미국자원 37개를 포함한 총 379개의 국내외 콩 유전자원에 대한 지방 함량과 지방산 조성을 평가하고 유용자원을 선발하여 고품질 콩 품종 개발의 기초자료로 활용코자 수행되었다. 한국자원과 중국자원은 농촌진흥청 농업유전자원센터로부터, 미국자원은 경북대학교 식물유전육종연구실로부터 분양 받았다. 콩 유전자원의 지방함량은 평균 19.1%이었고, 12.7∼26.0%의 범위이었고, 포화지방산인 palmitic acid의 함량은 평균 10.6%이었고 범위는 4.1∼18.1%, stearic acid의 함량은 평균 2.9%이었고 범위는 1.9∼12.7%이었다. 불포화지방산인 oleic acid의 함량은 평균 28.2%이었고 범위는 15.3∼56%, linoleic acid의 함량은 평균 51.2%이었고 범위는 24.4∼68%, linolenic acid의 함량은 평균 7.1%이었고 범위는 3.4∼11.1%이었다. linoleic (ω-6)/linolenic(ω-3) acid 함량의 비율은 평균 7.5이었고 범위는 3.8∼17이었다. 포화지방산이 평균 13.5%이었고 범위는 6.7∼21.7%, 그리고 불포화지방산의 함량은 평균 86.5%이었고, 범위는 78.3∼93.4%이었다. 고지방품종 개발을 위한 지방함량이 25%이상인 고지방함량 자원으로는 중국자원인 Suinong 14, Dongnong 434 및 Dongnong 46의 3개이었다. Oleic acid 함량이 50%이상인 고 oleic acid함량 자원으로는 미국자원인 KLG12073과 KLG12074, 중국자원인 Jilin 14 및 한국자원인 Kwangan과 Bongeui의 5개이었고, linoleic acid의 함량이 60%이상인 고 linoleic acid 함량 자원으로는 미국자원 KLG12083과 KLG12081을 포함한 8개이었다. Linolenic acid의 함량이 4%이하인 저 linolenic acid 함량 자원으로는 미국자원 KLG12093와 KLG12096을 포함한 7개이었다. Linoleic acid(ω-6)/linolenic acid(ω-3)의 비율이 4.5이하로 낮은 자원은 미국자원 KLG12074 (3.8)와 KLG12073 (3.8), 한국자원 Kwangan (3.8)와 Bongeui (4.5) 및 중국자원 Dongnong 47 (4.3)의 5개이었다.

본 연구는 된장 제조 시 자연발효 시킨 control과, B. subtilis KACC15935, B. subtilis HJ18-9균주를 starter로 접종하여 발효시킨 팽화미된장의 효소활성과 품질특성을 측정하였다. 환원당을 유리하는데 관여하는 α-amylase 효소활성의 경우 control과 HJ18-9를 접종한 시료에서 높게 나타났다. 또한 된장의 단백질을 분해하여 특유의 구수한 맛 성분을 유리하는 protease 활성의 경우도 control과 HJ18-9를 접종한 시료에서 높게 나타났으며, 이는 아미노태질소 함량에서도 같은 경향을 나타냈다. 또한 cellulose를 분해할 수 있는 능력을 가지고 있어 유용성분의 장내 이용성 증진을 위해 널리 사용되는 효소인 cellulase활성이 있는 HJ18-9균주를 처리한 접종구에서 115.45±30.05 unit/g로 control과 B. subtilis KACC15935 처리구에서 53.75±15.91, 43.75±13.51 unit/g 인 것에 비해 높게 나왔다. 이러한 결과로 본 연구를 통해 선별한 균주를 스타터로 접종하여 된장 제조에 알맞은 균주를 개발, 평가하여 가공품으로 개발의 기초연구가 되고자 하였다.

본 연구에서는 β-glucosidase활성이 있는 B. subtilis HJ18-9균을 접종하여 품종별로 청국장을 제조하여, 품종별 청국장의 품질특성과 isoflavone 함량 변화를 측정한 결과이다. 청국장의 단백질 분해 특유의 구수한 맛 성분을 유리하는 효소인 protease활성은 발효 전에는 새단백 청국장이 가장 높은 활성을 나타냈으며, 발효 후에는 우람 청국장이 가장 높은 protease활성을 나타냈다. 이는 구수한 맛 성분의 지표성분인 아미노태 질소함량과 같은 경향을 나타냈다. 환원당을 유리하는데 관여하는 a-amylase 활성은 새단백으로 제조한 청국장이 다른 품종에 비해 유의적으로 높은 함량을 나타냈으며 다섯가지 품종 모두 발효 후에 증가하는 경향을 나타냈다. 발효 후에 총 균수가 높아지는 경향을 나타냈으며 발효 초에는 우람 청국장이 유의적으로 높은 균수를 나타냈으나, 발효 후에는 품종 간에 유의적인 차이는 나타내지 않았다. 품종별 청국장의 isoflavone 함량은 발효초기에는 대풍, 우람 품종으로 제조한 청국장의 aglycone함량이 가장 높았으며, 48시간 발효 후에도 두 가지 품종이 각각 1249.04±9.14 ug/g, 589.32±14.08 ug/g로 가장 높은 aglycone 전환율 나타냈다. 이는 발효 초 aglycone함량에 비해 5.31, 1.94배 증가시켰다.

이 연구는 배의 가공식품으로의 활용도를 높이기 위해 배당침액을 제조하고 이를 이용하여 2종 소스(간장소스와 된장소스)를 개발하여 이화학적 특성과 저장성을 알아보고 훈제오리와의 조화도를 평가하여 육류요리와 어울리는 소스로서의 가능성을 제안하고자 하였다. 2종 소스는 이론적인 레시피와 다량조리 실험과 관능평가를 통하여 최종 레시피를 결정하였다. 또한 된장소스는 관능평가에 재료의 입자 크기가 미치는 영향을 최소한으로 줄이고자 마늘과 양파를 0.2cm 크기로 다진 것과 분쇄기에 분쇄한 두 가지 형태(된장소스 Ⅰ,Ⅱ)로 제조하여 관능평가 실시하여 그 결과 최종 소스를 확정하여 이후 이화학적 분석의 시료로 사용하였다. 된장소스 Ⅰ이 강도 관능평가에서 향미, 색깔, 맛, 전체적인 품질이 더 높게 평가되었고(p<0.05) 기호도 평가에서는 색깔, 맛, 산미, 훈제오리와의 조화도, 전체적인 선호도 에서 된장소스 Ⅱ보다 더 높은 점수를 받았다(p<0.05). 따라서 된장소스 Ⅰ을 선택하여 차 후 이화학적 분석 시료로 사용하였다. 간장소스와의 관능평가 결과 이취, 색깔, 점도는 간장소스가 유의적으로 된장소스 Ⅰ보다 더 높았으며(p<0.05) 냄새, 맛, 후미, 전체적인 품질은 된장소스 Ⅰ이 유의적으로 더 높았다(p<0.05). 두 소스의 기호도 평가에서는 된장소스 Ⅰ이 맛, 오리훈제와의 조화도, 전반적인 기호도 등에서 유의적으로 점수가 높았다(p<0.05). 배당침액의 총 폴리페놀 함량은 71.2±5 mg/100 g 이었고 DPPH radical 소거능은 9.7±3.7%, ABTSㆍ+ radical 소거능은 14.2±7.5%였다. 배당침액을 첨가한 소스의 총 폴리페놀 함량은 간장소스 147.7±12.6 mg/100 g, 된장소스 156.2±13.4 mg/100 g로 두 군이 유사하였다. 항산화 활성을 나타내는 DPPH radical 소거능은 간장소스 43.6±6.3%, 된장소스 17.0±5.0%로 간장소스의 활성이 높았고, ABTSㆍ+ radical 소거능은 간장소스 18.9±2.1%, 된장소스 17.0±9.0%로 두 소스가 유사하였다. 개발된 두 소스의 저장성 평가에서 pH, 염도, 미생물, 색도의 변화는 저장기간 동안 유의하지 않았고 당도는 간장소스 경우 저장기간에 따라 차이가 없었으나 된장소스는 증가하였다. 점도변화는 간장소스는 저장기간이 길어질수록 점도가 감소하였고, 된장소스는 증가하였다. 결론적으로 저장기간 동안 소스의 점도변화를 안정화시키면 배당침액을 첨가한 간장소스와 된장소스는 약간의 차이를 보이지만 배와 배당침액, 마늘, 양파 등 각 소스 재료의 다양한 기능성분을 함유하면서 항산화활성이 높고 저장성이 안정적인 육류 요리 소스로서 활용 가능성이 높다고 사료된다.

Much effort has been expended to find agronomically important QTLs for improving soybean yield. However, the complexity of genome, such as genome duplication, limits the utility of genome-wide association studies and linkage analyses to identify genes controlling yield traits. We propose the variation block method, a three-step process for recombination block detection and comparison. The first step is to detect variations by comparing short-read DNA sequences of the cultivar to a reference genome of the target crop. Next, sequence blocks with variation patterns are examined and defined. The boundaries between the variation-containing sequence blocks are regarded as recombination sites. All the assumed recombination sites in the cultivar set are used to split the genomes, and the resulting sequence regions are named as variation blocks. The practicality of this approach was demonstrated by the identification of a putative locus determining soybean hilum color and known genes such as flower color gene. We suggest that the variation block method is an efficient genomics method for recombination block-level comparison of crop genomes. We expect that this method holds the prospect of developing crop genomics by bringing genomics technology to the field of crop breeding.

Soybean [Glycine max (L.) Merr.] seeds are abundant in high-quality proteins and fats. In addition, soybean seeds are also rich in secondary metabolites, such as isoflavones, lecithin, and saponins. Triterpene saponins are major components of these physiologically active metabolites in soybean seeds. Soybean saponins are classified as group A and DDMP saponins. Among them group A saponins are undesirable component of food products due to bitterness and astringency and also cause foaming in tofu production. Whereas, DDMP saponins and their derivatives are less bitter and astringent and beneficial to human health when consumed as regular diet. Therefore, reducing the group A saponins or increasing the DDMP saponins are required to improve the food quality. The present study focused to identify and characterize the gene which is encoding a protein responsible for biosynthesis of DDMP saponins. EMS mutant lines (sg-7-1 & sg-7-2) which lack DDMP saponins were developed. The breeding cross has been made with these two mutants with two cultivars, Pungsannamul and Wooram to study the segregation and genetic linkage analysis, respectively. The segregation analysis showed that the mutant phenotype is controlled by single recessive gene. TLC analysis for phenotyping F2 population of Wooram X sg-7-1 showed mutant, wild and heterozygous types. To surprise two more patterns were detected and they were named as strange type1 (ST1) and strange type2 (ST2). Further, SSR marker analysis will be carried out to locate the gene which encoding a protein responsible for biosynthesis of DDMP saponins.

Soybean germplasm have diverse accessions with great variation in their ability to survive and reproduce under salt stress conditions. In general, cultivated soybeans are more sensitive to salt stress than their wild relatives, however exceptions are found in both the groups. These variations in response to salt stress makes soybean germplasm an interesting collection of genetic resources to be explored for the identification of salt-tolerance genes, and their mechanism of action. Here, in this report we presented a data showing differential response of selected accessions of both cultivated and wild soybeans to salt stress. Two modes of salt treatment; gradual salt stress (GS) as well as salt shock (SS) were used in this study. The GS was found more effective in finding the difference in response of soybean accessions to salt stress. Various genetic marker based methods are in use to identify and isolate the potential genes contributing to the salt tolerance in soybean. Even then there is a paucity of knowledge on the key genes contributing to the salt tolerance in soybean. We expect that a recently developed functional screen based method, like yeast based functional screen, using cDNA library generated from different salt tolerant accessions of soybean could lead to identification of novel genes responsible for salt tolerance in soybean. Also, we propose for the use of RNA isolated from different stages of GS and SS for making cDNA library to be used for functional screening.

Soybean [Glycine max (L.) Merr.] have a variety of flower colors which are controlled by six different genes (W1,W2,W3,W4,Wm, and Wp). Among these genes, mutation in W3 gene causes near white flowers in the background of w4 genotype whereas the genotype W3w4 does purple throat flowers. Earlier studies showed that dihydroflavonol 4-reductase1 (DFR1) gene was closely linked to the flower color variants for W3 locus. In order to find out the W3 gene responsible for w3 phenotype, we first, studied the candidate gene Glyma14g07940 (DFR1) which is having 100% similarity with DFR probe sequence. Sequence analysis of DFR1 between W3 and w3 soybeans showed one base substitution in exon 6 of w3 mutant soybean resulting in one amino acid change in the amino acid sequence. However, comparison of amino acid sequences of DFR proteins from various crop plants showed that there is no functional change in the protein. Besides, the promoter analysis showed that, 311 bp of indel was traced in 5’-upstream promoter region of DFR1 gene in the w3 mutant. Here, we show that the near white or purple throat phenotypes in G. max is associated with existence or nonexistence of indel at 5’- upstream promoter region and low or high expression of DFR1, respectively. These results suggest that w3 phenotype may be caused by certain regulator of DFR1 gene located near or distant from DFR1 in G. max. In further study, we need to check the correlation between promoter indel with W3 expression level through GUS analysis.

Soybean is a short-day plant, which means short day length promotes flowering. So far nine major loci, E1 to E8 and J, affecting the timing of flowering and maturity have been genetically identified in soybean. To understand the roles of soybean flowering genes in photoperiod-dependent flowering time control in soybean, we analyzed not only expression patterns of E1, E2, E3 and E4 genes as well as soybean FT homologs, including GmFT2a, GmFT5a and GmFT4, but also structural variation of E1, E2, E3, and E4 genes in various soybean accessions exhibiting a broad range of flowering time. The mRNA level of GmFT2a and GmFT5a was low in late flowering accessions, but high in late flowering accessions. In contrast, GmFT4 exhibited opposite expression pattern to those of GmFT2a and GmFT5a. Structural variation of E1, E2, E3 and E4 gene in these accessions revealed that early and moderate flowering accessions contained non-functional alleles of E1, E2, E3 and E4 genes in their genome. These results suggested that expression patterns of GmFT2a GmFT5a and GmFT4 would be important factor determining flowering time in soybean and allelic variation and genetic combination of upstream E1, E2, E3, and E4 genes would be more important in soybean flowering time control than their gene expression patterns.

High yield is the most important trait in various agricultural characteristics. Many approaches to improve yield have been tried in conventional agricultural practice and recently biotechnological tools employed for same goal. Genetic transformation of key genes to increase yield is one way to overcome current limitation in the field. We are producing transgenic soybean plants through high efficient transformation method by introducing all gene member with AT-hook binding domain, hoping to obtain manageable delay of senescence. Many transgenic soybean plants are growing in greenhouse and GMO field, and will be evaluated their senescence and any association with yield increase.

Major loci controlling flowering time and maturity of short-day plant soybean, E1, E2, E3, E4, E5, E6, E7 and E8, have been identified in soybean. The gene corresponding to E2 locus is a homolog of Arabidopsis GIGANTEA (AtGI). We identified three GI homologs in soybean and are verifying their roles in day-length dependent flowering. Expression anlysis indicated that GmGIs are ubiquitously expressed at all developmental stages of soybean plants. Diurnal expression of GmGIs fluctuates within light/dark cycles of long-day (LD) and short-day (SD). GmGI2 and GmGI3 have identical expression patterns under both day length conditions with the highest peak at zeitgeber time 8 h (ZT8) under LD and at ZT4 under SD. GmGI1 shows the peak at ZT12 under LD and at ZT8 under SD. All of GmGIs exhibit the earlier peak and the shorter phase under SD than LD. The results indicated that day length affects expressions of GmGIs. Subcellular localization analysis showed that GmGIs are mainly targeted to nucleus, similar to the localization of AtGI. Overexpression of GmGIs in Arabidopsis transgenic plants showed no significant effect on flowering time nor rescue of gi-2 mutant phenotype. The results suggested that GmGIs have different molecular functions in flowering time regulation of short-day plant soybean compared to long-day plant Arabidopsis. To investigate the molecular mechanisms of GmGIs’ functions in soybean flowering time control, we intend to identify target gene of GmGIs and interacting proteins by using yeast two-hybrid assay.

Soybean is a crop of importance economically and nutritionally in many parts of the world. Thanks to many new genes brought from genomic research, It is possible to introduce various candidate genes through genetic transformation to see the performance of the genes in field. In our lab, soybean transformations have been tried for last 10 years to probe the possibility of traits improvement by transformation of new gene into soybean. For this purpose, three different genes were transformed into Korean soybean variety, Kwangan. First, the gene that controls early flowering of plant was transformed into Kwangan. Second, a candidate gene for soybean mosaic virus (SMV) resistance was transformed to produce transgenic plants. Third, another candidate gene for drought tolerance was transformed. All the transgenic plants from three genes transformation were produced for their gene insertion and their expression using PCR, qRT-PCR. Further analysis including harvesting seeds is currently undertaken.

FT is one of the major floral activator in photoperiod-dependent flowering pathway. To understand the role of FT homologs in flowering time control of short-day plant soybean, we identified ten soybean FT genes and named GmFTs. Phylogenetic analysis revealed that ten GmFT genes were further categorized into three subclades. Gene expression analysis showed that the most GmFT genes are mainly expressed in leaves. The expression of GmFT2a, GmFT2b, GmFT5a, and GmFT6 was strongly induced under the floral inductive short-day condition, but GmFT4 exhibited opposite expression pattern compared to those of GmFT2a, GmFT2b, GmFT5a, and GmFT6. To understand roles of GmFT genes in flowering, we generated Arabidopsis transgenic plant overexpressing GmFT genes. Both 35S:GmFT2a and 35S:GmFT5a transgenic plants showed extremely early flowering. In contrast, overexpression of GmFT4 delayed flowering of transgenic plants compared to wild type Arabidopsis. The results indicated that GmFT2a and GmFT5a might function as floral activators, while GmFT4 has an opposite function in soybean flowering. Moreover, domain swapping approaches between GmFT2a and GmFT4 revealed that the substitution of the segment B region alone, which is located in 4th exon, was sufficient to change the function of GmFT2a to floral repressor and GmFT4 to floral activator. The results suggested that soybean FT homologs have been functionally diversified during evolution and might play different roles in photoperiod-dependent flowering of soybean.

The β-carotene biofortified transgenic soybean was developed recently through Agrobacterium -mediated transformation using the recombinant PAC (Phytoene synthase-2A-Carotene desaturase) gene in Korean soybean (Glycine max L. cv. Kwangan). GM crops prior to use as food or release into the environment required risk assessments to environment and human health in Korea. Generally, transgenic plants containing a copy of T-DNA were used for stable expression of desirable trait gene in risk assessments. Also, information about integration site of T-DNA can be used to test the hypothesis that the inserted DNA does not trigger production of unintended transgenic proteins, or disrupt plant genes, which may cause the transgenic crop to be harmful. As these reasons, we selected four transgenic soybean lines expressing carotenoid biosynthesis genes with a copy of T-DNA by using Southern blot analysis, and analyzed the integration sites of their T-DNA by using flanking sequence analysis. The results showed that, T-DNA of three transgenic soybean lines (7-1-1-1, 9-1-2, 10-10-1) was inserted within intergenic region of the soybean chromosome, while T-DNA of a transgenic soybean line (10-19-1) located exon region of chromosome 13. This data of integration site and flanking sequences is useful for the biosafety assessment and for the identification of the β-carotene biofortified transgenic soybean.

Soybean (Glycine max (L.) Merr) is a short day plant and has been adapted to various climates and environments during cultivation. However, the cultivation area is restricted to a very narrow range of latitudes. To date, nine major genes (E1 to E8 and J) have been reported to control the flowering time and maturity. Here, we evaluated the role of E2, E3, E4, and their paralogue genes in late flowering soybean cultivars under long day (LD) conditions using Soybean yellow common mosaic virus (SYCMV)-based virus-induced gene silencing (VIGS) system. A total of nine VIGS constructs were infiltrated into two fully expanded cotyledons and primary leaves. After inoculation with these VIGS constructs on Jangyeobkong, which is a late-flowering cultivar, phenotypic traits were evaluated for the first flowering dates (FFDs) and pod maturities under LD conditions. The FFDs of the silenced plants occurred 50-56 days after sowing (das), while the non-silenced plants bloomed on 60-61 days. We found that the E3 paralogue-silenced plants flowered the fastest and responsive genes were identified to be associated with the promotion of flowering time. As the knock-down of E3 paralogue, expression of E1 was up-regulated, E2 was no difference, E3 and E4 genes were down-regulated in the silenced plants. Expression of GmFT2a and GmFT5a is known to be controlled by E3 and E4. Interestingly, GmFT5a were highly expressed in SYCMV:E3 paralogue-silenced plants, whereas the expression of GmFT2a was not significant. These results support that GmFT5a is able to independently promote flowering under LD conditions.