Identifying leaf rust resistance gene Lr19 in durum wheat using simple sequence repeat (SSR) marker

Leaf rust, caused by Puccinia triticina Eriks., is an important disease affecting durum wheat (Triticum turgidum ssp. durum) worldwide, particularly in the Mediterranean region. The disease can be controlled through the use of plant host resistance. Based on seedling resistance tests of 103 durum genotypes against a bulk of P. triticina, urediniospores were previously collected from Syria and Lebanon during 2007/08 and 2008/09 growing seasons. Percentage of resistance in the durum set tested was up to 52%. The resistant genotypes might have one of the following resistance gene(s): Lr15, Lr 19, Lr 24, Lr 25, Lr 27 +31, Lr 28 and Lr 29. Results revealed that the Gb/130-bp polymorphic band was linked to Lr19 and Sr25. In this study, twelve genotypes carrying resistance to Lr19 and Sr25 have been identified (Azeghar2, Rutucha1, Ammar9/Azeghar2, Ammar9/Terbol97-4, T.polonicum9/Ch1//Icamor-TA04-68/3/Icamor-TA04-69//(Lahn/ Ch1)2519, Arislahn5//Icamor-TA04- 63/Icasyr1, T.dicoccum1/Ch1//Ammar8/3/Bonadur/Icamor-TA04-63, Mrb3/ T. urartu500651/4/Icamor- TA04-63/3/Bcr/Gro1// Mgnl1, SwAlg/Gd1-81 //Ch1-48, Icamor-TA04-1//Mgnl3/Ainzen1, 319-ADDO/5/D68-1- 93A-1A//Ruff/Fg/3/Mtl5/4/Lahn, and Mrf1/Stj2/3/1718/BT24//Karim). Promising results on Gb/130-bp and genotypes carrying Lr19 and Sr25 will be used in a marker assisted selection of the durum breeding programs in the Mediterranean region.Key words: Puccinia triticina, durum genotypes, Syria, Lebanon, Lr19, Sr25, Gb primer

TRITIMED; a multidisciplinary project to improve drought adaptation in durum wheat

none6noneHABASH D.; ARAUS J.L.; LATIRI K.; KADER A.A.; TUBEROSA R.; NACHIT M.HABASH D.; ARAUS J.L.; LATIRI K.; KADER A.A.; TUBEROSA R.; NACHIT M

Characterization of Moroccan Aegilops spp. for germplasm enhancement

Le but de cet article est de décrire la variation existante entre 149 accessions des espèces d’Aegilops collectées dans différentes régions du Maroc, d'examiner la distribution des variations morphophysiologiques et de résistance, et de déterminer la fréquence des caractères recherchés parmi les espèces. Les données prélevées au cours des essais expérimentaux ont été analysées à l’aide de l’analyse factorielle discriminante (DFA). Les trois premiers axes ont pu expliquer la totalité de la variation (Pr<5%). L’estimation des distances de Mahalobis a montré le rapprochement entre Ae. geniculata and Ae. triuncialis. La distribution des différentes accessions dans de nouveaux groupes a montré que 86,6% de celles-ci ont été affectées dans leur propre espèce. Treize accessions d’Ae. geniculata ont été placées dans le groupe d’Ae. triuncialis confirmant le rapprochement entre ces deux espèces. La plus grande variation a été celle d’Ae. geniculata pour les caractères précocité, étalement et densité. Aegilops ventricosa a été différenciée des autres espèces par la longueur de ses feuilles, sa tolérance pour la rouille foliaire et sa résistance à la cécidomyie. La quatrième espèce, Ae. neglecta a été la plus précoce et a combiné entre au moins trois types de résistance Les espèces spontanées resteront dans le réservoir génétique universel pour l’amélioration végétale. Elles doivent être préservées pour une durabilité des systèmes de production

Genotype-by-environment interactions of barley in the Mediterranean region

In the Mediterranean region, progress in selection for yield in harsh environments is hampered by large environmental variation between seasons and locations. This study analyses the genotype-by-environment (GE) interaction of 36 two-rowed genotypes of barley, grown in 14 environments in Syria and North Africa. It assesses the effect of growth type (winter or spring type) and heading date on the GE interaction and determines whether or not high-yielding (HY) environments are representative of low-yielding (LY) ones. Average grain yield per environment ranged from 7 to 513 g m-2. Genotypes and environments were classified by a cluster analysis and the interaction was analysed with an additive main effects and multiplicative interaction model. Genotypes were classified into four clusters, related to their growth type and earliness of heading. Environments were clustered into HY and LY groups; this classification was related to seasonal rainfall and temperature. Medium-early heading winter types had a positive interaction with LY environments and a negative interaction with HY environments, whereas late heading genotypes (spring and winter types) had the opposite interaction pattern. Early heading spring types had above-average mean yields; the highest-yielding among them tended to have a low interaction with environments. High-yielding environments did not discriminate well between genotypes with high or low yields in LY environments, and may thus have limited value for yield selection for LY environments. For a breeding programme aimed at improving yield in environments where favourable conditions are rare, selection for yield should be done in representative less-favourable environment

Sources of resistance in durum wheat and its wild relatives to Russian wheat aphid (Hemiptea: Aphididae)

Russian wheat aphid (RWA), Diuraphis noxia (Kurdjumov), is a serious pest of cereals in many parts of the world, particularly in dry areas. As limited resistance sources to this pest were previously identified in durum wheat, 144 accessions of Aegilops spp. and 72 advanced durum wheat lines were evaluated for resistance to RWA in the field and in the plastic house at Tel Hadya, Syria. Ten Aegilops accessions and 14 advanced durum wheat lines showed good level of resistance to RWA. The best five lines were studied for categories of resistance, and the results showed that antibiosis, antixenosis and tolerance are involved in various combinations

One-year prevalence and the impact of migraine and tension-type headache in Turkey: a nationwide home-based study in adults

Several studies have shown that the prevalence of migraine and tension-type headache (TTH) varied between different geographical regions. Therefore, there is a need of a nationwide prevalence study for headache in our country, located between Asia and Europe. This nationwide study was designed to estimate the 1-year prevalence of migraine and TTH and analyse the clinical features, the impact as well as the demographic and socio-economic characteristics of the participant households in Turkey. We planned to investigate 6,000 representative households in 21 cities of Turkey; and a total of 5,323 households (response rate of 89%) aged between 18 and 65 years were examined for headache by 33 trained physicians at home on the basis of the diagnostic criteria of the second edition of the International Classification of Headache Disorders (ICHD-II). The electronically registered questionnaire was based on the headache features, the associated symptoms, demographic and socio-economic situation and history. Of 5,323 participants (48.8% women; mean age 35.9 ± 12 years) 44.6% reported recurrent headaches during the last 1 year and 871 were diagnosed with migraine at a prevalence rate of 16.4% (8.5% in men and 24.6% in women), whereas only 270 were diagnosed with TTH at a prevalence rate of 5.1% (5.7% in men and 4.5% in women). The 1-year prevalence of probable migraine was 12.4% and probable TTH was 9.5% additionally. The rate of migraine with aura among migraineurs was 21.5%. The prevalence of migraine was highest among 35–40-year-old women while there were no differences in age groups among men and in TTH overall. More than 2/3 of migraineurs had ever consulted a physician whereas only 1/3 of patients with TTH had ever consulted a physician. For women, the migraine prevalence was higher among the ones with a lower income, while among men, it did not show any change by income. Migraine prevalence was lower in those with a lower educational status compared to those with a high educational status. Chronic daily headache was present in 3.3% and the prevalence of medication overuse headache was 2.1% in our population. There was an important impact of migraine with a monthly frequency of 5.9 ± 6, and an attack duration of 35.1 ± 72 h, but only 4.9% were on prophylactic treatment. The one-year prevalence of migraine estimated as 16.4% was similar or even higher than world-wide reported migraine prevalence figures and identical to a previous nation-wide study conducted in 1998, whereas the TTH prevalence was much lower using the same methodology with the ICHD-II criteria