Authors:B. Siahsar, S. Peighambari, A. Taleii, M. Naghavi, A. Nabipour, and A. Sarrafi
Abdel-Haleem, H., Giroux, M., Talbert, H., Bowman, J., Kanazin, V., Blake, T. 2004. Identification of QTLs controlling the feed quality of barley. Plant & Animal Genome XII Conf., Jan. 10–14, 2004, San Diego, CA. p. 468
Authors:M. R. Simón, F. M. Ayala, M. V. Moreno, U. Lohwasser, and A. Börner
Tan spot, caused by the fungus Pyrenophora tritici-repentis (Died.) Drechs is an important foliar disease of wheat (Triticum aestivum L.). From a set of phenotypically and molecularly characterized set of Argentinean isolates, two isolates H0019 and H0120 which do not correspond to known races of the pathogen were selected. Segregation for resistance among a set of recombinant inbred lines bred from the cross ‘W7984’ × cv. ‘Opata 85’ was used to identify the basis for resistance at the seedling stage, against those fungal isolates (H0019 and H0120), across three independent environments. On the basis of the mean performance across all three environments, a QTL against chlorosis located on the 6AS and linked to the RFLP locus Xksuh4c was significant for both isolates (with a LOD of 3.76 for isolate H0019 and 5.87 for H0120).
Authors:S.M. Pirseyedi, A. Kumar, F. Ghavami, J.B. Hegstad, M. Mergoum, M. Mazaheri, S.F. Kianian, and E.M. Elias
Fusarium head blight (FHB) damage in durum wheat (Triticum turgidum L. var. durum Desf., turgidum) inflicted massive economic losses worldwide. Meanwhile, FHB resistant durum wheat germplasm is extremely limited. ‘Tunisian108’ is a newly identified tetraploid wheat with FHB resistance. However, genomic regions in ‘Tunisian108’ that significantly associated with FHB resistance are yet unclear. Therefore, a population of 171 backcross inbred lines (BC1F7) derived from a cross between ‘Tunisian108’ and a susceptible durum cultivar ‘Ben’ was characterized. Fusarium graminearum (R010, R1267, and R1322) was point inoculated (greenhouse) or spawn inoculated (field) in 2010 and 2011. Disease severity, Fusarium-damaged kernel (FDK) and mycotoxins were measured. Analysis of variance showed significant genotype and genotype by environment effect on all traits. Approximately 8% of the lines in field and 25% of the lines in greenhouse were more resistance than Tunisian108. A framework linkage map of 267 DArt plus 62 SSR markers was developed representing 239 unique loci and covering a total distance of 1887.6 cM. Composite interval mapping revealed nine QTL for FHB severity, four QTL for DON, and four QTL for FDK on seven chromosomes. Two novel QTL, Qfhb.ndsu-3BL and Qfhb.ndsu-2B, were identified for disease severity, explaining 11 and 6% of the phenotypic variation, respectively. Also, a QTL with large effect on severity and a QTL with negative effect on FDK on chromosome 5A were identified. Importantly, a novel region on chromosome 2B was identified with multiple FHB resistance. Validation on these QTL would facilitate the durum wheat resistance breeding.
Authors:K. Wajdzik, G. Gołębiowska, M. Dyda, K. Gawrońska, M. Rapacz, and M. Wędzony
The increasing economic importance of triticale (×Triticosecale Wittm.) makes this synthetic hybrid cereal an interesting object of genetic studies. Genomic regions (QTL) of morphological winter triticale traits were determined using the mapping population of 89 doubled haploids lines (DHs) developed from F1 hybrid of cv. ‘Hewo’ and cv. ‘Magnat’ accompanied with the genetic map consisting of 20 linkage groups assigned to the A (7), B (7), and R (6) genomes (total of 3539 DArT, SNP-DArT and SSR markers, length of 4997.4 cM). Five independent experiments were performed in the field and greenhouse controlled conditions. A total of 12 major QTLs located on 2B, 5A, 5R, and 6B chromosomes connected to the stem length, the plant height, the spike length, the number of the productive spikelets per spike, the number of grains per spike, and the thousand kernel weight were identified by a composite interval mapping (CIM).
Authors:F. Anzala, M.-C. Mor?re-Le Paven, C. Birolleau-Touchard, C. Giauffret, and A. M. Limami
Radicle elongation that allows rhizosphere colonization was used as a marker of seedling establishment. The goal of the present work was to determine the genetic basis of the effect of the aspartate family pathway, in particular lysine, on the radicle elongation of maize seedlings. For this purpose a population derived from an advanced backcross between a flint European line F2 and a highland tropical line F334 as the donor parent, was used for mapping QTLs related to the effect of lysine on radicle elongation. The parental lines showed contrasting germination efficiency and root elongation under both control conditions (imbibition on water at 20°C) and on medium supplied with lysine. Two QTLs for radicle elongation under control conditions were located on chromosome 2 (136 cM) near the marker bnlg1721 and on chromosome 5 (146 cM) near the marker umc1792. These QTLs explained 9.4% and 10.5%, respectively, of the phenotypic variability for radicle elongation. When germination was carried out on medium containing 5 mM lysine, three QTLs for radicle elongation were located on chromosome 7 (90 cM) near the marker umc1112, on chromosome 10 (42 cM) near the marker bnlg1037 and on chromosome 10 (68 cM) near the marker umc1053; these QTLs explained 12.0%, 12.3% and 12.4%, respectively, of the phenotypic variability for radicle elongation. Irrespective of the germination and post-germination medium, favourable alleles for all detected QTLs were associated with parental line F334.
Authors:S. Marghali, H. Chennaoui, H. Bourguiba, M. Marrakchi, and N. Trifi-Farah
Amplified fragment length polymorphism (AFLP) has been proposed as a valuable tool for finding molecular markers linked to QTL controlling architectural trait. Segregation of polymorphic AFLP fragments was followed in F2 offsprings Hedysarum coronarium derived from two native wild accesions crossing: Jebel Zit×El Haouaria, which had previously characterised by morphological and AFLP markers. A comparison of profiles from the morphologically contrasted parental individuals and F2 offspring has been assessed using five AFLP primer combinations. These generated 178 bands revealed by silver-stained denaturing polyacrylamide gels, of which 150 were polymorphic. Several AFLP markers appeared to be implied in the orthotropic form that can assist the selection and improve Hedysarum forage crop.