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cultivars by the use of the ph1 gene (Riley and Chapman, 1958) that promotes homeologous chromosome Rust resistance genes Lr37, Sr38, and Yr17 are located within a recombination. The ph1 mutation has been extensively segment of Triticum ventricosum (Tausch) Cess. chromosome 2NS translocated to the short arm of bread wheat chromosome 2AS. Char-used to incorporate new disease resistance genes in acterization of this chromosome segment by 13 restriction fragment wheat from wild Triticeae species such as T. monococlength polymorphism (RFLP) markers indicated that the 2NS translocum L., T. speltoides (Tausch) Gren., and T. ventricosum cation replaced approximately half of the short arm of chromosome (McIntosh et al., 1995; Friebe et al., 1996; Dubcovsky 2A (distal 25-38 centimorgans, cM). The objective of this study was et al., 1998). to develop polymerase chain reaction (PCR) assays based on RFLP The Yr17, Lr37, and Sr38 rust resistance genes, which marker cMWG682 to facilitate the transfer of this cluster of rust confer resistance in wheat against stripe rust (caused by resistance genes into commercial wheat (Triticum aestivum L.) culti-Puccinia striiformis West. f. sp. tritici), leaf rust (caused vars. DNA sequence was obtained from the A-, B-, D-, and N-alleles by Puccinia triticina Eriks), and stem rust (caused by of cMWG682 and was used to design N-allele specific primers. The Puccinia graminis Pers. f. sp. tritici Eriks. & E. Henn.), 2NS fragment amplified by PCR primers cosegregated with the presence of the RFLP-2NS band in all backcross populations. A cleaved respectively, have been used by breeders in different amplified polymorphic sequence (CAPS) was used to develop a parts of the world (Dyck and Lukow, 1988; McIntosh marker for the 2A-allele. This marker can be used to differentiate et al., 1995; Robert et al., 1999; Seah et al., 2000). These homozygous and heterozygous plants carrying the 2NS translocation linked resistance genes were initially introgressed in the in the final cycle of backcross introgression or in screenings for homowinter bread wheat 'VPM1' from Triticum ventricosum zygous plants in segregating populations. Finally, a third PCR assay (Maia, 1967) and are located in a 2NS/2AS translocation was developed by means of TaqMan technology as a high-throughput (Bariana and McIntosh, 1993;McIntosh et al., 1995). alternative for selection of the 2NS/2AS translocation in large segre-Rust races with virulence to Yr17 and Lr37 have been gating populations in breeding programs that have access to real time identified in different countries (Robert et al., 1999; PCR equipment. These molecular markers were used to develop four J. Kolmer unpublished data) but this gene cluster still hard red spring isogenic lines homozygous for the 2NS chromosome segment. One of the isogenic lines, derived from 'Anza,' did not show provides resistance to a wide range of races and is useful the expected resistance in spite of the presence of all the RFLP in combination with other rust resistance genes. markers for the ...

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Abstract. Mental fatigue is considered to be a contributing factor responsible for numerous road accidents and various medical conditions and the efficiency and performance could be impaired during fatigue. Hence, determining how to evaluate mental fatigue is very important. In the present study, ten subjects performed a long-term visual search task with electroencephalogram recorded, and self-assessment and reaction time (RT) were combined to verify if mental fatigue had been induced and were also used as confirmatory tests for the proposed measures. The changes in relative energy in four wavebands į ș Į and ȕ), four ratio formulas [(D + T)/E, D/E, (D + T)/(D + E), and T/E], and Shannon's entropy (SE) were compared and analyzed between the beginning and end of the task. The results showed that a significant increase occurred in alpha activity in the frontal, central, posterior temporal, parietal, and occipital lobes, and a dip occurred in the beta activity in the pre-frontal, inferior frontal, posterior temporal, and occipital lobes. The ratio formulas clearly increased in all of these brain regions except the temporal region, where only D/E changed obviously after finishing the 60-min visual search task. SE significantly increased in the posterior temporal, parietal, and occipital lobes. These results demonstrate some potential indicators for mental fatigue detection and evaluation, which can be applied in the future development of countermeasures to fatigue.