A new Hessian fly (Mayetiola destructor Say) resistance gene from Aegilops triuncialis and its transfer to hexaploid wheat via interspecific hybridisation is described. The transfer line TR-3531 (42 chromosomes), derived from the cross [(Triticum turgidum x Ae. triuncialis) x Triticum aestivum] and carrying the Heterodera avenae resistance gene Cre7, showed a high level of resistance to the M. destructor biotype prevailing in the SW of Spain. A single dominant gene (H30) seems to determine the Hessian fly resistance in this introgression line, and its linkage with an isozyme marker (Acph-U1) has also been studied. It has been demonstrated that the resistance gene H30 in the TR-3531 line is non-allelic with respect to the genes H3, H6, H9, H11, H12, H13, H18 and H21, present in wheat cultivars from the Uniform Hessian Fly Nursery (UHFN), as well as to H27, carried by the introgression line H-93-33. Advanced lines with the H30 gene were obtained by backcrossing the transfer line and different commercial wheats as recurrent parents. Several of them showed a high yield in tests carried out in the infested field. Electronic Supplementary Material is available if you access this article at http://dx.doi.org/10.1007/s00122-002-1182-z. On that page (frame on the left side), a link takes you directly to the supplementary material.

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Water and carbon fluxes in forests are largely related to leaf gas exchange physiology 27 varying across spatiotemporal scales and modulated by plant responses to environmental cues. 28 We quantified the relevance of genetic and phenotypic variation of intrinsic water-use 29 efficiency (WUEi, ratio of net photosynthesis to stomatal conductance of water) in Pinus 30 sylvestris L. growing in the Iberian Peninsula as inferred from tree-ring carbon isotopes. Inter-31 population genetic variation, evaluated in a provenance trial comprising Spanish and German 32 populations, was low and relevant only at continental scale. In contrast, phenotypic variation, 33 evaluated in natural stands (at spatial level) and by tree-ring chronologies (at temporal inter-34 annual level), was important and ten-and threefold larger than the population genetic 35 variance, respectively. These results points to preponderance of plastic responses dominating 36 variability in WUEi for this species. Spatial phenotypic variation in WUEi correlated 37 negatively with soil depth (r=-0.66; p<0.01), while temporal phenotypic variation was mainly 38 driven by summer precipitation. At the spatial level, WUEi could be scaled-up to ecosystem-39 level WUE derived from remote sensing data by accounting for soil water holding capacity 40 (r= 0.63; p<0.01). This outcome demonstrates a direct influence of the variation of leaf-level 41 WUEi on ecosystem water and carbon balance differentiation. Our findings highlight the 42 contrasting importance of genetic variation (negligible) and plastic responses in WUEi (large, 43 with changes of up to 33% among sites) on determining carbon and water budgets at stand 44 and ecosystem scales in a widespread conifer such as Pinus sylvestris.