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

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

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

AdipoRon enhances healthspan in middle‐aged obese mice: striking alleviation of myosteatosis and muscle degenerative markers

BackgroundObesity among older adults has increased tremendously. Obesity accelerates ageing and predisposes toage-related conditions and diseases, such as loss of endurance capacity, insulin resistance and features of the metabolicsyndrome. Namely, ectopic lipids play a key role in the development of nonalcoholic fatty liver disease (NAFLD) andmyosteatosis, two severe burdens of ageing and metabolic diseases. Adiponectin (ApN) is a hormone, mainly secretedby adipocytes, which exerts insulin-sensitizing and fat-burning properties in several tissues including the liver and themuscle. Its overexpression also increases lifespan in mice. In this study, we investigated whether an ApN receptor ag-onist, AdipoRon (AR), could slow muscle dysfunction, myosteatosis and degenerative muscle markers in middle-agedobese mice. The effects on myosteatosis were compared with those on NAFLD.MethodsThree groups of mice were studied up to 62 weeks of age: One group received normal diet (ND), another,high-fat diet (HFD); and the last, HFD combined with AR given orally for almost 1 year. An additional group of youngmice under an ND was used. Treadmill tests and micro-computed tomography (CT) were carried out in vivo. Histolog-ical, biochemical and molecular analyses were performed on tissues ex vivo. Bodipy staining was used to assessintramyocellular lipid (IMCL) and lipid droplet morphology.ResultsAR did not markedly alter diet-induced obesity. Yet, this treatment rescued exercise endurance in obese mice(up to 2.4-fold,P<0.05), an event that preceded the improvement of insulin sensitivity. Dorsal muscles and liver den-sities, measured by CT, were reduced in obese mice ( 42% and 109%, respectively,P<0.0001), suggesting fatty in-filtration. This reduction tended to be attenuated by AR. Accordingly, AR significantly mitigated steatosis and cellularballooning at liver histology, thereby decreasing the NALFD activity score ( 30%,P<0.05). AR also strikingly reversedIMCL accumulation either due to ageing in oxidativefibres (types 1/2a, soleus) or to HFD in glycolytic ones (types2x/2b, extensor digitorum longus) ( 50% to 85%,P<0.05 or less). Size of subsarcolemmal lipid droplets, knownto be associated with adverse metabolic outcomes, was reduced as well. Alleviation of myosteatosis resulted from im-proved mitochondrial function and lipid oxidation. Meanwhile, AR halved aged-related accumulation of dysfunctionalproteins identified as tubular aggregates and cylindrical spirals by electron microscopy (P<0.05).ConclusionsLong-term AdipoRon treatment promotes‘healthy ageing’in obese middle-aged mice by enhancing en-durance and protecting skeletal muscle and liver against the adverse metabolic and degenerative effects of ageingand caloric excess.University College de Londres (UCL) de Reino Unido - FSR 2017Société Francophone du Diabète de Francia/Roche Diabetes Care de España 2020National Fund for Scientific Research de Bélgica - FNRS 35275437, 201