Soil-borne barley yellow mosaic disease caused by Barley yellow mosaic virus (BaYMV) or Barley mild mosaic virus (BaMMV) gives a serious threat to the winter barley cultivated in the southern regions in Korea. It is important to develop resistant varieties for stable and high-yield production. The objectives of this study were to evaluate 22 genotypes of exotic barley germplasms carrying the resistance genes rym1 through rym12, with the exception of rym10, and to determine the genes that confer resistance to BaYMV or BaMMV in Korea. Using the traditional visual scoring of symptoms at 4 locations over 3 years, average disease rate values differed (P < 0.001) among the genotypes. ELISA test revealed the presence of both BaYMV and BaMMV in all of the field sites but Jinju and significantly different rates of infection among genotypes and years. Barley genotypes differed in how virus quantities and pathogen-induced symptoms were correlated, especially in response to BaYMV. Disease incidence was affected by the climatic conditions present during the early growing stage before overwintering. A Chinese landrace, 'Mokusekko 3', carrying rym1 and rym5 was comparatively resistant at all locations studied. The barley genotypes carrying either rym6 or rym9 were susceptible to the viral strains. The genotypes carrying rym5 were resistant in Jinju and Milyang but susceptible in Iksan and Naju. The resistance genes rym2 and rym3 were effective in local strains and would be potent contributors to disease resistance.

Nano-pattering process by low-voltage electron beam lithography based on microcolumn with beam energy of 500 eV has been developed. Low kV exposure provides the advantages of high sensitivity, reduced charging, and a lack of proximity and heating effects. However a low-voltage electron beam has very thin penetration range. At 500 V, the penetration range is less than 20 nm, while typical resist thickness is > 200 nm. A resist process with bilayer scheme, 17 nm-thick PMMA resist on 100 nm-thick SiO 2 layer, and wet etch method was demonstrated for 250 nm line patterns transfer to Si substrate. The process was applied to fabricate periodic grating patterns on a silicon substrate. The results of nano-pattern process by low energy microcolumn lithography will be discussed in detail.