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.

Steroidal glycoalkaloids which serve the plant defense, are toxic secondary metabolites present in the plants of solanaceae family. The upper safe limit of glycoalkaloids for human consumption is 20mg/KG FW, excess of which may cause severe health disorders. Several factors like drought, high temperature, light exposure, and wounding increase tuber glycoalkaloid content. Among these, drought is an important factor which causes a rapid increase in potato glycoalkaloid content. Glycoalkaloid biosynthetic genes and their expression pattern need to be characterized to regulate the glycoalkaloid accumulation. Three key genes SGT1, SGT2 and SGT3 are demonstrated to be directly participated in the biosynthetic pathway for glycoalkaloid formation. Present study was focused on the study of expression pattern of key genes in GA pathway under drought stress in two different potato cultivars Atlantic and Haryoung which are low and high glycoalkaloid accumulating respectively. Drought stress was imposed by withholding water to the plants grown in pots and control plants kept irrigated. Expression analysis of SGT1, SGT2 and SGT3 was done from the leaf and tuber sample of three time intervals i.e 5, 10 and 20 days after imposing stress. Variation in the expression level of genes was observed in leaf and tuber where the fold increase in expression over control was higher in tuber sample compared to leaf. Expression levels also varied in leaf and tuber among two cultivars. However, expression of SGT1, SGT2 and SGT3 is significant indicating the involvement of these genes in glycoalkaloid accumulation under drought stress.

Korean soybean variety Kwangan was transformed with coat protein (CP), helper component-proteinase (HC-Pro), and ABRE binding factor 3 (ABF3) genes using highly efficient soybean transformation system. Among these genes, CP and HC-Pro were transformed using RNAi technology. Transgenic plants with CP were confirmed for gene introduction and their expression using PCR, real-time PCR, RT-PCR, Southern blot, and Northern blot. To investigate the response of viral infection with CP, T1 plants were inoculated with SMV-infected leaves and confirmed the existence of mosaic symptom in both leaves and seeds. Two transgenic lines with CP were highly resistant to SMV with clear leaves and seeds while SMV-susceptible lines showed mosaic symptom with seed mottling. The transcript levels of T1 plants with CP were also determined by northern blot, suggesting that SMV-resistant T1 plants did not show viral RNA expression whereas SMV-susceptible T1 plants showed viral RNA expression. Currently, the response of viral infection with HC-Pro is investigating to produce SMV-resistant soybean transgenic plants, and the physiological experiment with ABF3 is also carrying out to produce drought-tolerant soybean transgenic plants.

SOHLH2 is a novel germ cell-specific transcription factor that is crucial for folliculogenesis in the ovary and spermatogenesis in the testis. SOHLH2 represents a candidate gene for infertility with premature ovarian failure. We analyzed whether mutations in the SOHLH2 gene in 98 Korean women with premature ovarian failure. The sequence analysis identified six novel SNPs (c.431-41G>C, c.656A>T, c.1000+27C>T, c.1000+33G>T, c1258-106G>A, and c.2094+ 11T>C) from Korean patients with premature ovarian failure. The c.656A>T found in exon 7 results in change of an amino acid, tyrosine to phenylalanine. Functional mutations in SOHLH2 gene are rare in Korean women with premature ovarian failure.

A new waxy corn hybrid ‘Daedukchal 1’ was developed from single cross between CNU 504 and CNU 2396 at Chungnam National University in 2007. Inbred CNU 504 used as a seed parent and inbred CNU 2396 as a pollen parent were collected throughout domestic regions. Tasseling date of this hybrid was seven days later than that of check hybrid, ‘Chalok 1’. ‘Daedukchal 1’ was 19.7 cm in ear length and 4.5 cm in ear diameter. On yield trial, ear length of this hybrid was increased 29.7% compared with a check hybrid, ‘Chalok 1’. ‘Daedukchal 1’ had white kernels and good eating quality due to high sugar content and thinner pericarp. The ratio of kernel set length/ear length was similar to ‘Chalok 1’. It is moderately resistant to southern leaf blight and northern leaf blight but susceptible to corn borer. The yields of ‘Daedukchal 1’ in fresh ear weight and in number of fresh ear were 16% and 8%, respectively, higher than those of a check hybrid in regional yield trials for two years. Seed production for this hybrid was better because of the consistency of tasseling dates.

Inbred lines were gained from corn genetic resources collected by our lab and also deveolped by our Corn Breeding Lab. Materials used were eleven hybrids including yellow waxy corn hybrid CNU19 (applied as Daehakchal Gold 1 in 2007). These hybrids were harvested at 30th day after fertilization for antioxidants activity analysis; polyphenol compounds, inhibitory effect of xanthin oxidase activity, catalase activity, superoxide dismutase activity and DPPH radical scavenging activity. Daehakchal Gold 1 among hybrids were midseason variety and higher than check Chalok 1. The ratio of ear height to stem height was low as 50% below. Kernel set ratio was also higher than check hybrid. Among antioxidant analysis, Polyphenol compound was the highest in Daehakchal Gold 1 (CNU 19) as 3.77μg/ml, and CNU 21, CNU 93 and CNU153 including check were high trend compared to others. Xantine oxidase(OX) catalase activity, SOD activity and DPPH radical scavenging effect by using methanol extracts were also comparatively higher in CNU 19 hybrid than others. Besides, catalase activities of Daehakchal Gold 1 hybrid extracted by methanol and haxane were higher than other hybrids. From experiment results, this hybrid was superior to other used hybrids in botanical character, table quality and funtion.