International audienceWith standardised near isogenic line (NIL) differentials co-operators were able to present the first comprehensive virulence survey of the European wheat leaf rust population (1996-1999). The work included pathotype identification of 2608 isolates and field tests of NILs. Lr9 and Lr19 were very effective all over Europe. Lr24, Lr25, and Lr28 were also effective, but in some countries and locations substantial virulence frequencies were observed. In addition, the genes Lr12, Lr13, Lr22a, Lr34, Lr35 and Lr37 were effective at the adult plant stage, but locally less so. In general, the indoor seedling tests and adult plant field tests showed good agreement. Virulence to Lr1, Lr2a, Lr24, Lr25, Lr28 and Lr29 tended to increase in the period, for the other Lr-genes the virulence frequency remained more or less stable. Among the 105 pathotypes identified none was clearly predominant in Europe.La situation en Europe pour la virulence de la rouille brune chez le blé. L'utilisation d'une gamme d'hôtes différentiels commune composée de lignées isogéniques (NIL) a permis aux auteurs de réaliser le premier inventaire exhaustif de la population européenne de rouille brune du blé (1996-1999). Deux mille six cent huit isolats ont été identifiés et les NIL ont été évaluées au champ. Lr9 et Lr19 se sont révélés efficaces dans toute l'Europe. Lr24, Lr25 et Lr28 ont également été efficaces, mais la fréquence des virulences correspondantes était non négligeable dans certains pays et certains lieux. Les gènes Lr12, Lr13, Lr22a, Lr34, Lr35 et Lr37 ont été efficaces au stade adulte, excepté dans quelques lieux. En général, les résultats des tests au stade plantule en conditions contrôlées ont été cohérents avec ceux obtenus au stade adulte au champ. Les fréquences de virulence sont demeurées stables au cours de la période étudiée, sauf pour Lr1, Lr2a, Lr24, Lr25 et Lr29, dont les fréquences de virulence correspondantes tendaient à augmenter. Aucun des 105 pathotypes identifiés n'est apparu clairement dominant en Europe

-Seventy two wheat cultivars and breeding lines were tested for at least two years in up to ten European countries for resistance against leaf rust under field conditions. In addition, seedling resistance was determined with local races and with defined isolates to postulate resistance genes. Nine entries (Batis, Capo, RE9001, RE9801, Terza, Toronit, Titlis, Barra, Beaufort) were highly resistant at all locations, and were regarded as excellent sources of resistance for breeding programs. Two thirds of the 72 entries possess adult plant and/or partial resistance. Cultivars with the gene Lr13 differed greatly in disease response showing that Lr13 alone does not provide adequate resistance in Europe. Gene Lr37 provided generally good adult plant resistance but seedlings with this gene were moderately susceptible. Many of the wheat cultivars/lines investigated possess unidentified adult plant resistance gene(s). Seedling resistance was attributable mostly to the genes Lr1, Lr3a, Lr3ka, Lr10, Lr14a, Lr17b, Lr20 or Lr26. Triticum aestivum / Puccinia recondita / wheat / leaf rust / resistance Résumé -Résistance du germplasme de blé d'hiver européen à la rouille des feuilles. Pendant au moins deux ans, 72 cultivars et lignées de sélection avancées de blé ont été testées aux champs dans dix pays européens pour évaluer la résistance à la rouille des feuilles. De plus, la résistance a été évaluée lors d'essais en laboratoire sur des plantules infec-

During routine wheat disease surveys in Hungary in 2007 Alternaria was isolated from leaf samples collected in Debrecen. Macro- and micro-morphological examinations and ITS sequence analyses indicated that the isolates represented a new Alternaria species, which we described as A. hungarica. The usually solitary conidia of A. hungarica resemble those of A. mouchaccae and A. molesta. However growth and sporulation pattern are more like those of A. geniostomatis and A. soliaridae. Phylogenetic analysis of ITS sequences indicated that this new species can be distinguished from all other examined Alternaria and Embellisia species. Pathogenicity tests indicated that A. hungarica can be considered a minor pathogen of wheat.

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