Drought tolerance is the ability of a plant to live, grow, and reproduce properly with limited water supply or under periodic conditions of water deficit. However, the climate changes and worldwide water shortages would result in the loss of applied water to irrigated land, increasing soil water deficit. To control the situation, we have carried out the international joint research project for the aim of developing that drought tolerance common wheat and durum wheat in Korea and Tunisia. Total 79 (41 common wheat, 39 durum wheat) Tunisian lines and 33 Korean wheat cultivars were incorporated in this study. Drought stress was applied for 25 days of stopping irrigation from the 3-leaf stage followed by re-watering for restoration in greenhouse. We selected top 13 (5 Korean line, 8 Tunisian line) tolerant lines and 11 (5 Korean, 6 Tunisian) susceptible lines based on growth parameter analysis. Primers (Operon primers and wheat Dreb1 gene) that have been known to be related drought resistance were applied to explain selected population. The correlation between PCR-based length polymorphism of selected lines and their resistance were evaluated. The obtained primer information will aid selection for drought tolerance durum as well as hexaploid common wheat.

Compared to wide ranges of genetic variation of natural populations, very limited Miscanthus cultivar has been released. This study was the first report on the development of Miscanthus cultivar by means of radiation breeding. Seeds of M. sinensis were initially exposed to gamma rays of 250 Gy for 24 h, generated from a 60Co gamma-irradiator. The irradiated seeds were sown and then the highly tiller-producing mutants were selected for this study. Biomass-related parameters including tiller number, plant height, stem diameter, and leaf number were measured. Ploidy level and internal transcribed spacer (ITS) were investigated to characterize the mutants compared to wild type (WT) Miscanthus. Plant height and tiller number were negatively related, where multi-tillering mutants were relatively short after 4 month growth. However stem diameter and leaf number were greater in mutants. All the materials used in this study were diploid, implying that the mutants with greater tiller numbers and stem diameter were not likely related to polyploidization. Based on the sequence of ITS regions, the mutants demonstrated base changes from the gamma irradiation where G+C content (%) was decreased in the ITS1, but increased in ITS2 when compared to WT sequence. ITS2 region was more variable than in ITS1 in the mutants, which collectively allows identification of the mutants from WT. Those mutants having enhanced tillers and allelic variations might be used as breeding materials for enhanced biomass-producing Miscanthus cultivars.

Wild rice might have previously unidentified genes important for disease resistance and stress tolerance in response to biotic and abiotic stresses. A set of subtractive library was constructed both from leaves of wild rice plants, Oryza grandiglumis (CCDD, 2n=48), treated with fungal elicitor and from wounded leaves. A partial fragment that was homologous to PR10 genes from other plant species was identified via suppression subtractive hybridization and cDNA macroarray. The obtained full-length cDNA sequence (OgPR10) contains an open reading frame of 480 bp nucleotide, encoding 160 amino acids with a predicted molecular mass of 16.944 kDa and an isoelectric point (pI) of 4.91. The multiple alignment analyses showed the higher sequence homology of OgPR10 with PR10 genes identified in rice plants at amino acid level. The OgPR10 mRNA was not expressed by treatment with wounding, jasmonic acid, and salicylic acid, but markedly expressed in leaves treated with protein phosphatase inhibitors cantharidin and endothall, and yeast extract. In addition, the expression of OgPR10 mRNA was induced within 72 h after treatment with probenazole, one of well-known chemical elicitors, and reached the highest level at 144 h. Heterologous expression of OgPR10 caused growth inhibition and seedling lethality in E. coli and Arabidopsis, respectively. Chemically induced OgPR10 expression with glucocorticoid-mediated transcriptional induction system further reconfirmed its lethality on Arabidopsis seedling. In addition, OgPR10-expressing rice plants, Oryzae sativar were resistant against the infection of rice blast fungus, Magnaporthe grisea. These results indicate that OgPR10 is involved in probenazole- and microbe associated molecular patterns-mediated disease resistance responses in plants and is a potential gene for developing disease resistance crop plants.

Estrogens are ubiquitous signaling molecules that influence nearly every cell type, and exert profound effects on embryonic development, and differentiation. Wnt pathway, which recruits β-catenin into nuclei, and activates The Wnt-dependent transcription factors, also plays an important role in embryonic development and stem cell maintenance, and differentiation. Accumulating evidences indicate that potential convergence between these two pathways in carcinoma cells. However, physiological roles of estrogens in development and differentiation of human embryonic stem cells (hESCs) are relatively unknown. Here, we demonstrated that estrogenic compounds 17α-ethinylestradiol (EE2) and genistein (GEN) significantly increased β-catenin expression in undifferentiated hESCs cultured in feeder-free media. Interestingly, GEN treatement induced an increased trend of mesendodermal gene expressions, and significantly inhibited ectodermal gene expressions (Nestin and Pax6) in embrioid body (EB). Expectantly, GEN increased epithelial-mesenchymal transition (EMT) related gene expression (Snail2, and Twist), whereas decreased E-cadherin on day 6 of EB development. Taken together, these suggest that estrogens may in part the powerful effects on normal hESC differentiation. Mechanistic studies of estrogen signaling continue to suggest novel drug targets for stem cells and will also improve screening methods of developmental toxicity.

"Oraebyeo" is mutation of a high quality japonica cultivar, Ilpumbyeoa new japonica rice(Oriza sativa L.) cultivar developed from by N-methyl-N-nitrosourea(MNU) treatment on fertilized egg cell by the rice breeding team of Gangwon Provincial Agricultural Res. & Ext. Service in 2006. This variety heads 20 days earlier than Ilpumbyeo and similar to that of Odaebyeo an early maturing leading cultivar of northern plain area of Korea. Compared with Odaebyeo has a good semi-erect plant type with lodging tolerance due to much shortened plant hight(l2cm shorter than Odaebyeo). Oraebyeo has similar panicle number with Odaebye where as it has more spikelets per panicle. However, this variety less the ratio of ripened grains and 1,000 grain weight than those of Odaebyeo. The yield performance of this cultivar in milled rice was about 5.09MT/ha in local adaptability test conducted for three years 2002-2004 and 5.51MT/ha in the demonstration plot of farmer's field.

Sanggolbyeo is a new japonica rice cultivar developed from Ilpumbyeo mutation lines by N-methyl-N-nitrosourea(MNU) treatment on fertilized egg cell by the rice breeding team of Gangwon Provincial Agricultural Res.& Ext. Service in 2006. This cultivar has about 135 days growth duration from transplanting to harvesting. Sanggolbyeo has short and round grain and non-glutinous endosperm with very low phytate content, below 50% of Ilpumbyeo, implying it could help men to absorb Calcium from rice. This cultivar shows midium diseases tolerance to leaf blast, bacterial blight, virus and insect pest. The milled rice yield of Sanggolbyeo is about 4.98 MT/ha at ordinary transplanting culture in the local adaptability test. Sanggolbyeo would be adaptable for the mid-northern plain areas of Korea.

Tocopherol belongs to the Vitamin E class of lipid soluble antioxidants that are essential for human nutrition. Tocopherols consist of a chromanol ring and a 15-carbon tail derived from homogentisate (HGA) and phytyl diphosphate, respectively. Condensation of HGA and phytyl diphosphate, the committed step in tocopherol biosynthesis, is catalyzed by HGA phytyltransferase (HPT). To increase tocopherol level in cucumber fruit, we performed Agrobacterium-mediated transformation with mdhpt gene, encoding HPT, isolated from apple (Malus domestica). We obtained two independent T0 cucumber plants from transforming 2,142 explants. Southern blot analysis of T0 showed that mdhpt was inserted in the genome. In order to test the tocopherol level, T1 cucumber fruits were screened by GC analysis. From 39 T1 fruits tested, some fruits showed 1.5-2 fold in α- and β-tocopherol content comparing to control. However, most of fruits contained lower levels of γ- and δ- tocopherol indicating a partition of metabolites in tocopherol biosynthesis pathway. We selected these T1 line and made a self-cross to obtain T2 seeds.