Identification of the PCR markers tightly linked to genes that encode important agronomic traits is useful for marker-assisted selection (MAS). The rice Pi5(t) locus confers broad-spectrum resistance to Magnaporthe grisea, the causal agent of rice blast disease. It has been hypothesized that the Pi5(t) locus carries the same gene as that encoded by the Pi3(t) and Pii(t) loci. We developed three PCR-based dominant markers (JJ80-T3, JJ81-T3, and JJ113-T3) from three previously identified BIBAC clones-JJ80, JJ81, and JJ113-that are linked to the Pi5 (t) locus. PCR analysis of 24 monogenic lines revealed that these markers are present only in lines that carry Pi5 (t), Pi3(t), and Pii(t). PCR and DNA gel-blot analysis of candidate resistance lines using JJ80-T3, JJ81-T3, and JJ113-T3 indicated that Tetep is the likely donor of Pi5(t).Of the 184 rice varieties tested, 34 carried the JJ80-T3-, JJ81-T3-, and JJ113-T3-specific bands. Disease evaluation of those 34 varieties revealed that all conferred resistance to PO6-6. The genomic structure of three of these resistant varieties (i.e., IR72, Taebaeg, Jahyangdo) is most similar to that of Pi5(t). Our results demonstrate the usefulness of the JJ80-T3, JJ81-T3, and JJ113-T3 markers for MAS for M. grisea resistance.

61.72.Vv -Doping and impurity implantation in III-V and II-VI semiconductors PACS 71.20.-b -Electron density of states and band structure of crystalline solidsAbstract -The ferromagnetic properties of (Zn,Co)O were observed by a magnetometer at low temperatures. This is, however, inconsistent with the results from the magneto-optical measurements. They reflect the presence of Co metal precipitates in (Zn,Co)O. On the other hand, the formation of Co metal precipitates was strongly suppressed by the additional Cu doping. It appears that the formation of Co metal precipitates is related to the carrier concentration in the system.