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mapping population [ND2603(Sumai 3/Wheaton)/Butte 86] (Anderson et al., 2001). The best SSR markers ex-A major QTL (quantitative trait locus) for Fusarium head blight plained 41.6 and 24.8% of the variation in FHB resis-(FHB) resistance, Qfhs.ndsu-3BS, derived from 'Sumai 3', has been identified and verified by several research groups via molecular tance in the two mapping populations (Anderson et al., marker analysis. Further study of this QTL is worthwhile because it 2001). Bai et al. (1999) reported AFLP (amplified length explains a large portion (25-60%) of the variation in FHB resistance polymorphism) markers for a major QTL that explained in the reported studies. The objectives of this study were to (i) identify up to 60% of the variation for FHB resistance. This additional molecular markers for Qfhs.ndsu-3BS, (ii) construct a cyto-QTL was derived from 'Ning7840', which is believed to logically based physical map of chromosome 3BS, and (iii) identify have inherited its FHB resistance from Sumai 3 (Liu germplasm with novel FHB resistance genes with SSR markers near and Wang, 1990). After integration of SSR markers into Qfhs.ndsu-3BS. Two new simple sequence repeat (SSR) markers the original AFLP maps, this QTL was assigned to a (XBARC133 and XBARC102), two sequence tagged site (STS) marksimilar position as Qfhs.ndsu-3BS (Zhou et al., 2000). ers (XSTS3B1 and Xsun2), and one restriction fragment length poly-Furthermore, Qfhs.ndsu-3BS was also identified in a morphism (RFLP) marker (Xfbb185), were mapped to the Qfhs.ndsu-3BS region. On the basis of deletion line analysis, this major QTL is double-haploid mapping population of a cross 'CMlikely located on the deletion bin 3BS 0.78-0.87. Fifty-four FHB resis-82036'(Sumai 3/'Thornbird-S')/'Remus' and explained tant lines from throughout the world and 20 North American spring up to 60% of the phenotypic variance for Type II FHB wheat (Triticum aestivum L.) lines of historical prominence were resistance (Buerstmayr et al., 2002). genotyped by five SSR markers (Xgwm389, Xgwm533, XBARC133, Although Sumai 3 and its derivatives have been suc-Xgwm493, and XBARC102) associated with Qfhs.ndsu-3BS. The cessfully used as FHB resistance sources worldwide, Sumai 3 haplotype is rare. Only 25 out of 54 FHB resistant lines and additional resistance genes are needed to avoid comone North American spring wheat line have Sumai 3-type alleles for plete dependence on only a few genes from one source. at least one of these five SSR markers. Twelve FHB resistant lines Moreover, the FHB resistance level is not high enough have the same SSR allele as Sumai 3 for at least four of the five SSR to prevent economic damage under high disease presmarkers, and therefore most likely contain this major QTL. The other 42 FHB resistant lines may carry novel FHB resistance genes, and

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De-NO, catalysts with strong mechanical properties and high surface area have been prepared by coating silica microspheres with titania according to the homogeneous deposition-precipitation method. The proportion of titania incorporated was varied between 0.5 and 3.0 theoretical monolayers. These catalysts possess a titanialike behaviour and strong acid properties. Although the Ti-Si carriers are titania-rich, the TiO, phase is relatively well dispersed and the change in the coordination sphere of TiO, induced by the silica substrate may account for its strong acid properties. Upon incorporation of vanadium, both dispersed vanadium species and V,O, crystallites are developed, the former being similar to vanadia species on TiO,. These systems exhibit both strong acidity and redox properties which are primarily associated with characteristics peculiar to the support and the V,O, components, respectively, which play a key role in the de-NO, reaction. Preliminary results on the CO + NO reaction indicate that these catalysts have a much better performance than VTiO, .

Control of selectivity in the hydrogenation of 1,3-butadiene is achieved by tuning the graphite-supported Pd catalyst’s properties.