Superlattices are attracting extensive attention due to their unique properties. Nevertheless, the observations of superlattices are limited to those layered structures with weak interlayered interactions, and the effect of the superlattice in metal-based nanostructures on catalysis is unexplored yet. We here report a facile wet-chemical method for synthesizing two-dimensional Ru multilayered nanosheets (Ru MNSs) with a superlattice. Characterizations reveal that the superlattice is formed by stacking Ru layers with twisted angles from 2°to 30°. Owing to the strong synergy between the adjacent layers, Ru MNSs can serve as an efficient catalyst for the alkaline hydrogen evolution reaction (HER). Theoretical calculations reveal that the superlattice can induce the strain effect, which leads to lattice contraction and weak *H adsorption ability, as a result of improved HER performance. This work sheds new light on the utilization of the superlattice on enhancing catalysis in metal-based materials.

Wheat scab (Fusarium Head Blight, FHB) is a destructive disease in the warm and humid wheat-growing areas of the world. Finding diverse sources of FHB resistance is critical for genetic diversity of resistance for wheat breeding programs. Leymus racemosus is a wild perennial relative of wheat and is highly resistant to FHB. Three wheat- L. racemosus disomic addition (DA) lines DA 5 Lr#1, DA 7 Lr#1 and DALr.7 resistant to FHB were used to develop wheat- L.racemosus translocation lines through irradiation and gametocidal gene-induced chromosome breakage. A total of nine wheat-alien translocation lines with wheat scab resistance were identified by chromosome C-banding, GISH, telosomic pairing and RFLP analyses. In line NAU 614, the long arm of 5 Lr#1 was translocated to wheat chromosome 6B. Four lines, NAU 601, NAU 615, NAU 617, and NAU 635, had a part of the short arm of 7 Lr#1 transferred to different wheat chromosomes. Four other lines, NAU 611, NAU 634, NAU 633, and NAU 618, contained translocations involving Leymus chromosome Lr.7 and different wheat chromosomes. The resistance level of the translocation lines with a single alien chromosome segment was higher than the susceptible wheat parent Chinese Spring but lower than the alien resistant parent L. racemosus. At least three resistance genes in L. racemosus were identified. One was located on chromosome Lr.7, and two could be assigned to the long arm of 5 Lr#1 and the short arm of 7 Lr#1.

Previous studies showed that a T. aestivum-H. villosa disomic substitution line DS4V(4D) showed a high level of resistance to wheat spindle streak mosaic virus (WSSMV). By crossing DS4V(4D) with the common wheat variety Yangmai #5, plants were obtained that were double monosomic for chromosomes 4V and 4D. Univalents are prone to misdivision at the centromere, and fusion of the derived telocentric chromosomes leads to the production of Robertsonian whole-arm translocations. We screened the progenies of such double monosomic plants by C-banding and genomic in situ hybridization and identified one compensating translocation where the short arm of 4V was translocated to the long arm of 4D of wheat, T4VS·4DL. RFLP analysis using the group-4 specific probe BCD110 was used to confirm the translocation. The T4VS·4DL translocation stock, accessioned as NAU413, is highly resistant to WSSMV and is also of good agronomic type. The WSSMV resistance gene located on 4VS was designated Wss1.

A doubled haploid (DH) wheat population derived from the cross Wangshuibai/Alondra's' was developed through chromosome doubling of haploids generated by anther culture of hybrids. Fusarium head blight (FHB) was evaluated for three years from 2001 to 2003 in Jianyang, Fujian Province, China, where epidemics of FHB have been consistently severe. After 307 pairs of simple sequence repeat (SSR) primers were screened, 110 pairs were polymorphic between Wangshuibai and Alondra's', and used to construct a genetic linkage map for detection of quantitative trait loci (QTLs). A stable QTL for low FHB severity was detected on chromosomes 3B over all three years, and QTLs on chromosomes 5B, 2D, and 7A were detected over two years. Additional QTLs on chromosomes 3A, 3D, 4B, 5A, 5D, 6B and 7B showed marginal significance in only one year. Six QTLs were detected when phenotypic data from three years were combined. In addition, significant additive-by-additive epistasis was detected for a QTL on 6A although its additive effect was not significant. Additive effects (A) and additive-by-additive epistasis (AA) explained a major portion of the phenotypic variation (76.5%) for FHB response. Xgwm533-3B and Xgwm335-5B were the closest markers to QTLs, and have potential to be used as selectable markers for marker-assisted selection (MAS) in wheat breeding programs.

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