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Introduction Interspecific and intergeneric hybridization between cereal species has theoretical and practical importance in fields like cytogenetics, evolution research, and plant breeding. Species related to wheat possess large genetic diversity [...], The 3HS.3BL spontaneous Robertsonian translocation obtained from the progenies of wheat-barley (Chinese Spring x Betzes) hybrids backcrossed with wheat line Mv9kr1 was transferred into the modern Martonvasar wheat cultivar Mv Bodri. The translocation was identified with molecular cytogenetic methods. The inheritance of the translocation was traced using genomic in situ hybridization. Fluorescence in situ hybridization using barley subtelomeric (HvT01) and centromere-specific [[(AGGGAG).sub.4] repetitive DNA probes confirmed that the complete barley chromosome arm was involved in the Robertsonian translocation. The wheat-specific repetitive DNA probes identified the presence of the whole wheat genome, except the short arm of the 3B chromosome. Genotypes homozygous for the centric fusion were selected, after which morphological analysis was performed on the plants and the yield components were measured in the field during two consecutive vegetative seasons. The introgression of the 3HS.3BL translocation into the modern wheat cultivar Mv Bodri significantly reduced the plant height due to the incorporation of the dwarfing allele RhtDlb. The presence of the 3HS.3BL translocation in the Mv9kr1 and Mv Bodri wheat background improved tillering and seeds per plant productivity in field experiments carried out in Martonvasar and Keszthely, Hungary. Key words: wheat-barley Robertsonian translocation, fluorescence in situ hybridization, yield components, tillering, dwarfing allele. La translocation robertsonienne spontanee 3HS.3BL obtenue au sein des progenitures d'hybrides ble-orge (Chinese Spring x Betzes) retrocroisees avec la lignee de ble Mv9kr1 a ete introduite au sein de la variete moderne de ble Mv Bodri developpee a Martonvasar. La translocation a ete identifiee a l'aide de methodes de cytogenetique moleculaire. La transmission de la translocation a ete suivie au moyen de l'hybridation genomique in situ. L'hybridation in situ en fluorescence, a l'aide de sondes composees de sequences repetees subtelomeriques (HvT01) ou centromeriques [[(AGGGAG).sub.4], a permis de confirmer que le bras entier du chromosome de l'orge est compris dans la translocation robertsonienne. Des sondes specifiques du ble ont permis de confirmer la presence du genome entier du ble a l'exception du bras court du chromosome 3B. Les individus homozygotes pour la fusion centrique ont ete selectionnes, apres quoi une analyse morphologique et des mesures des composantes de rendement ont ete realisees au champ au cours de deux saisons consecutives sur ces plantes. L'introgression de la translocation 3HS.3BL au sein du cultivar moderne de ble Mv Bodri a significativement reduit la taille des plantes en raison de l'incorporation de l'allele de nanisme RhtDlb. La presence de la translocation 3HS.3BL dans les fonds genetiques Mv9kr1 et Mv Bodri a ameliore le tallage et la productivite en termes de graines par plante lors des essais realises au champ a Martonvasar et a Keszthely, en Hongrie. [Traduit par la Redaction] Mots-cles: ble-orge translocation robertsonienne, hybridation en fluorescence in situ, composantes du rendement, tallage, allele de nanisme.

Introduction Micronutrients are essential parts of the human diet, and in some cases the alimentary disorders caused by an insufficient daily intake may lead to serious illnesses. Zinc (Zn) is [...], [3M.sup.b] Triticum aestivum L. (Mv9kr1)- Aegilops biuncialis Vis. (MvGB642) addition lines were crossed with the Chinese Spring ph1b mutant genotype (CSph1b) to produce [3M.sup.b]-wheat chromosome rearrangements. In the [F.sub.3] generation, [3M.sup.b](4B) substitution lines and [3M.sup.b].4BS centric fusions were identified with in situ hybridization using repetitive and genomic DNA probes, and with SSR markers. Grain micronutrient analysis showed that the investigated Ae. biuncialis accession MvGB382 and the parental line MvGB642 are suitable gene sources for improving the grain micronutrient content of wheat, as they have higher K, Zn, Fe, and Mn contents. The results suggested that the Ae. biuncialis chromosome [3M.sup.b] carries genes determining the grain micronutrient content, as the [3M.sup.b].4BS centric fusion had significantly higher Zn and Mn contents compared with the recipient wheat cultivar. As yield-related traits, such as the number of tillers, the length of main spike, and spikelets per main spike, were similar in the [3M.sup.b].4BS centric fusion and the parental wheat genotype, it can be concluded that this line could be used in pre-breeding programs aimed at enriching elite wheat cultivars with essential micronutrients. Key words: Triticum aestivum, Aegilops biuncialis, [3M.sup.b](4B) substitution, [3M.sup.b].4BS centric fusion, sequential FISH and GISH, grain micronutrient content. Des lignees d'addition [3M.sup.b] Triticum aestivum L. (Mv9kr1)--Aegilops biuncialis Vis. (MvGB642) ont ete croisees avec le mutant Chinese Springph1b (CSph1b) afin de produire des rearrangements chromosomiques [3M.sup.b]-ble. Au sein de la generation [F.sub.3], des lignees de substitution [3M.sup.b](4B) et des fusions centriques [3M.sup.b].4BS ont ete identifiees par hybridation in situ au moyen de sondes d'ADN repete ou genomique ainsi qu'avec des marqueurs SSR. Une analyse de la composition du grain en matiere de micronutriments a montre que l'accession etudiee de l'Ae. biuncialis (MvGB382) et la lignee parentale MvGB642 constituent des sources valables pour ameliorer le contenu en micronutriments chez le ble, du fait qu'elles ont une teneur accrue en K, Zn, Fe et Mn. Ces resultats suggerent que le chromosome [3M.sup.b] de l'Ae. biuncialis porte des genes contribuant a determiner le contenu en micronutriments puisque la fusion centrique [3M.sup.b].4BS presentait un contenu en Zn et en Mn significativement superieur a la variete de ble receptrice. Puisque les composantes de rendement comme le nombre de talles, la longueur de la tige principale et le nombre d'epillets par epi etaient semblables chez la fusion centrique [3M.sup.b].4BS et chez le genotype de ble parental, les auteurs en concluent que cette lignee pourrait s'averer utile dans des programmes de pre-selection visant a accroitre la teneur en micronutriments essentiels chez les cultivars elites de ble. [Traduit par la Redaction] Mots-cles: Triticum aestivum, Aegilops biuncialis, substitution [3M.sup.b](4B), fusion centrique [3M.sup.b].4BS, analyses FISH et GISH sequentielles, teneur en micronutriments chez le grain.

Introduction Wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) are both important cereals worldwide. The intergeneric hybridization of these species makes it possible to transfer agronomically useful genes (e.g., [...], To increase the allelic variation in wheat-barley introgressions, new wheat-barley disomic addition lines were developed containing the 2H, 3H, 4H, 6H, and 7H chromosomes of the six-rowed Ukrainian winter barley 'Manas'. This cultivar is agronomically much better adapted to Central European environmental conditions than the two-rowed spring barley 'Betzes' previously used. A single 'Asakaze' x 'Manas' wheat x barley hybrid plant was multiplied in vitro and one backcross plant was obtained after pollinating 354 regenerant hybrids with wheat. The addition lines were selected from the self- fertilized seeds of the 16 [BC.sub.2] plants using genomic in situ hybridization. The addition lines were identified by fluorescence in situ hybridization using repetitive DNA probes (HvT01, GAA, pTa71, and Afa family), followed by confirmation with barley SSR markers. The addition lines were grown in the phytotron and in the field, and morphological parameters (plant height, fertility, tillering, and spike characteristics) were measured. The production of the disomic additions will make it possible to incorporate the DNA of six-rowed winter barley into the wheat genome. Addition lines are useful for genetic studies on the traits of six-rowed winter barley and for producing new barley dissection lines. Key words: Triticum aestivum, Hordeum vulgare, wheat-barley addition lines, in situ hybridization, SSR markers. Afin d'accroitre la variation allelique au sein d'introgressions ble-orge, de nouvelles lignees d'addition disomiques ble-orge ont ete produites en introduisant les chromosomes 2H, 3H, 4H, 6H et 7H du cultivar ukrainien 'Manas', une orge d'hiver a six rangs. Ce cultivar offre une bien meilleure adaptation agronomique aux conditions environnementales de l'Europe centrale que l'orge a deux 'Betzes' employee precedemment. Un seul hybride ble x orge 'Asakaze' x 'Manas' a ete multiplie in vitro et un seul plant a ete obtenu apres retrocroisement avec le ble de 354 plantes hybrides regenerees. Les lignees d'addition ont ete selectionnees au moyen de l'hybridation genomique in situ au sein de graines issues de l'autofe-condation de 16 plantes [BC.sub.2]. Les lignees d'addition ont ete identifiees par hybridation in situ en fluorescence (FISH) a l'aide de sondes d'ADN repete (HvT01, GAA, pTa71 et la famille Afa), suivie d'une confirmation a l'aide de marqueurs SSR de l'orge. Les lignees d'addition ont ete cultivees en phytotron et au champ, et des parametres morphologiques (taille, fecondite, tallage, caracteristiques de l'epi) ont ete mesures. La production de ces lignees d'addition rendra possible l'incorporation d'ADN de l'orge d'hiver a six rangs au sein du genome du ble. Les lignees d'addition sont utiles pour des etudes genetiques sur les caracteres presents chez l'orge d'hiver a six rangs de meme que pour produire de nouvelles lignees de dissection chez l'orge. Mots-cles : Triticum aestivum, Hordeum vulgare, lignees d'addition ble-orge, hybridation in situ, marqueurs SSR. [Traduit par la Redaction]

The frequency and pattern of irradiation-induced intergenomic chromosome rearrangements were analysed in the mutagenized ([M.sub.0]) and the first selfed ([M.sub.1]) generations of Triticum aestivum L.--Aegilops biuncialis Vis. amphiploids (2n = 70, AABBDD[U.sup.b][U.sup.b][M.sup.b]][M.sup.b]) by multicolour genomic in situ hybridization (mcGISH). mcGISH allowed the simultaneous discrimination of individual Ae. biuncialis genomes and wheat chromosomes. Dicentric chromosomes, fragments, and terminal translocations were most frequently induced by [gamma]-irradiation, but centric fusions and internal exchanges were also more abundant in the treated plants than in control amphiploids. Rearrangements involving the [M.sup.b] genome ([M.sup.b]-type aberrations) were more frequent than those involving the [M.sup.b] genome ([M.sup.b]-type aberrations). This irradiation sensitivity of the [U.sup.b] chromosomes was attributed to their centromeric or near-centromeric regions, since [M.sup.b]-type centric fusions were significantly more abundant than [U.sup.b]-type centric fusions at all irradiation doses. Dicentrics completely disappeared, but centric fusions and translocations were well transmitted from [M.sub.0] to [M.sub.1]. Identification of specific chromosomes involved in some rearrangements was attempted by sequential fluorescence in situ hybridization with a mix of repeated DNA probes and GISH on the same slide. The irradiated amphiploids formed fewer seeds than untreated plants, but normal levels of fertility were recovered in their offspring. The irradiation-induced wheat--Ae. biuncialis intergenomic translocations will facilitate the successful introgression of drought tolerance and other alien traits into bread wheat. Key words: Triticum aestivum, Aegilops biuncialis, amphiploid, [gamma]-irradiation, intergenomic translocations, mcGISH. La frequence et la nature des rearrangements chromosomiques intergenomiques induits par irradiation ont ete analyses au sein de la generation irradiee (Mo) et de la generation suivante ([M.sub.1]) d'amphidiploides Triticum aestivum L.--Aegilops biuncialis Vis. (2n = 70, AABBDD[U.sup.b][U.sup.b][M.sup.b][M.sup.b]) par hybridation genomique in situ multicolore (mcGISH). L'hybridation mcGISH a permis de simultanement identifier les genomes de l'Ae. biuncialis et les chromosomes individuels du ble. Des chromosomes dicentriques, des fragments et des translocations terminales etaient les plus frequemment induits par irradiation [gamma], mais des fusions centriques et des echanges internes etaient egalement plus abondants chez les plantes traitees que chez les amphidiploides temoins. Des rearrangements impliquant le genome [U.sup.b] (aberrations de type [U.sup.b]) etaient plus frequentes que celles impliquant le genome [M.sup.b] (aberrations de type [M.sup.b]). Cette sensibilite a l'irradiation des chromosomes [U.sup.b] a ete attribuee a leurs regions centromeriques ou pericentromeriques puisque des fusions centriques de type [U.sup.b] etaient significativement plus abondantes que les fusions centriques de type [M.sup.b] a toutes les doses d'irradiation. Les chromosomes dicentriques ont totalement disparu tandis que les fusions centriques et les translocations etaient bien transmises de la [M.sub.0] a la [M.sub.1]. L'identification de chromosomes specifiques impliques dans certains rearrangements a ete tentee par hybridation in situ en fluorescence sequentielle avec une combinaison de plusieurs sondes d'ADN repetitif et d'hybridation GISH sur la meme lame. Les amphidiploides irradies ont forme moins de graines que les plantes temoins, mais des niveaux normaux de fecondite ont ete retrouves au sein de leur descendance. Les translocations intergenomiques ble--Ae. biuncialis induites par irradiation faciliteront l'introgression de la resistance a la secheresse et d'autres caracteres d'interet de l'espece exotique vers le ble. Mots-cles: Triticum aestivum, Aegilops biuncialis, amphiploide, irradiation y, translocations intergenomiques, mcGISH. [Traduit par la Redaction], Introduction Aegilops biuncialis Vis. (2n = 4x = 28, [U.sup.b][U.sup.b][M.sup.b][M.sup.b]) is an allotetraploid species having good tolerance against biotic (Damania and Pecetti 1990; Makkouk et al. 1994) and abiotic stresses [...]

Abstract: The short interspersed nuclear element (SINE), Au, was used to develop sequence-specific amplified polymorphism (S-SAP) markers for U- and M-genome chromosomes. The markers were localized using Triticum aestivum (wheat)--Aegilops [...]

Barley development and actual yield is strongly affected by a number of environmental stress factors that can prevent the plant from expressing its maximum genetic potential. Indeed abiotic stresses (temperatures, drought, anaerobiosis and soil salinity) are often responsible for severe grain losses although they have driven the evolution and the wide distribution of the genus Hordeum in temperate, subtropical and arctic areas. We present a new resource to dissect natural allelic variation at candidate genes controlling key adaptive traits in barley, based on a collection of 500 accessions assembled in the context of the EU-FP7-WHEALBI (Wheat and Barley Legacy for Breeding Improvement) project. The collection comprises 227 old and elite cultivars, 238 landraces and 35 wild barleys (H. spontaneum) from a wide geographical range. Winter and spring nurseries (common garden trials) have been carried out in 4 contrasting environments (Scotland, North Italy, Hungary and Central Anatolia in Turkey, in this last site under both rainfed and irrigated conditions) and several phenological and morphological traits have been evaluated. Moreover, a comprehensive molecular variant analysis by exome sequencing (exome capture arrays) has been carried out, resulting in more than 2 million SNPs and InDels. Plant growth habit and heading-date are the basic traits involved in barley adaptation to the environment since they allow synchronize life cycle with seasonal changes. Several genes involved in these key adaptive traits have been characterized and they can serve as a proof of concept to validate the effectiveness of WHEALBI resource in mining new functional alleles. To this purpose allelic diversity of candidate genes has been evaluated in wild, landraces and cultivated barley to determine the extent of haplotype diversity and build haplotype networks. The genetic diversity of barley CBF and Vrn-H1, two key loci responsible for frost tolerance, have been explored in 403 barley accessions using the exome sequencing information. This dataset along with curated annotation of the CBF genes provided the means to identify unique SNP variants in HvCBF genes and predict functional effects at the protein level. A large proportion of these SNPs were observed in the gene pool of barley landraces and wild relatives, only being fixed in the cultivated germplasm. Similarly, examining diversity at the winter allele of Vrn-H1, from Hordeum vulgare cv. Strider, as reference, several unknown deletions of this gene were identified as well as one accession with two copies of Vrn-H1 gene. To date, the genetic variants (SNPs and CNVs) of coding sequences developed and validated in this project are a snapshot of the existing genetic variability of barley, which will enable the research community to mine interesting alleles for other traits and exploit the untapped genetic diversity of barley. [ABSTRACT FROM AUTHOR]