Seed storage proteins of different solubility were extracted and denatured subunits of each protein were evaluated with malting barley quality parameters. Its been known that each subunit of seed storage protein encoded by each gene and subunit profiles were highly related to end-use quality in cereals. The purpose of this study is to provide selection criteria for high quality malting barleys with aid of bichemical-genetic information. Total 13 regional test lines and three locations (Naju, Jinju, and Jeju) were incorporated in this study. Albumin and hordein were extracted, denatured, and separated in 12% SDS-PAGE. Presence and absence of subunits of each protein were scored. Dendrogram (using XLSTAT program) was constructed to evaluated the relatedness of lines. The correlation between band profiles and quality test were assessed through Agglomerative Hierarchical Clustering (AHC) for statistics analysis. Hordein subunits can be classified into four groups, A, B, C, and D group. In general, hordein fractions contribute higher than albumine to determine malting quality. Specific molecular weight ranges (97.4-31.0, 66.2-31.0, and 45.0-31.0 kDa) of subunits were highly correlated with malting barley quality parameters. The subunit information would be directly incorporated in providing selection criteria for high quality malting barley in the malting barley breeding program.

Pectin, one of the main components of plant cell wall, is deesterified in muro by PME (Pectin methylesterase). PME activity is particularly regulated by inhibitor proteins known as the pectin methylesterase inhibitor (PMEI). The PMEI plays a key role in wounding, osmotic stress, senescence and seed development. However, the role of PMEI in plant species still remains to be demonstrated especially in wheat. To facilitate the studies on the expression of the TaPMEI gene, RT-PCR was performed using leaf, stem and root tissues in response to exogeneous application of phytohormones and abiotic stress treatments. Transcription of the TaPMEI gene was significantly induced in NaCl, H2O2 and SA treatments, and reduced when plants were treated with ABA. To elucidate the subcellular localization of the TaPMEI protein, TaPMEI:GFP fusion construct was transformed into onion epidermal cells by particle bombardment. The fluorescence signal was exclusively detected in cell wall of the cells. In order to obtain recombinant TaPMEI protein, the TaPMEI protein, expressed in E.coli as a MBP (~42.5 kDa) fusion protein recombinant. Purification and functinal analysis of TaPMEI as an inhibitor of PME activity are described.

It was previously pointed out that mutation is the ultimate source of variation. Adequate variation is needed for plant breeding if there is a limitation in natural genetic resources. When the ionizing radiation has been known to cause chromosomal and genomic alternations, it is widely used for inducing mutagenesis. The electron beam as an ionizing radiation is the principal physical mutagens that induces mutation and effectively used in plant breeding. Since dose-response relationships of electron beam in plant species are rarely known, we investigated the seed germination rate and early seedling growth of irradiated seeds of creeping bentgrass (Agrostis palustris Huds., cv Penn-A1) with various electron beam irradiating conditions (1, 1.3, 2 MeV at both 0.03 mA and 0.06 mA with dose of 100 Gy (Gray) and 0.03, 1, 1.3, 2 MeV at 0.03 mA with dose of 200 Gy, respectively) using electron accelerator at Korea Atomic Energy Research Institute. The growth parameters in terms of shoot length, primary root length, and secondary root length showed similar response between 0.06 / 1 (mA / MeV) at 100 Gy and 0.03 / 0.3 (mA / MeV) at 200 Gy. Bentgrass seed germination was mainly affected by the intensity of irradiated dose (Gray). Germination rate was lowered as the irradiated dose increased. On the other hand, early seedling growth was mainly governed not by the dose of radiation but by voltage.