1 / 26

Khaled F M Salem

Application of Biotechnology Tools in Egyptian Bread Wheat Breeding. Khaled F M Salem. Wheat Science to textbooks, 5-10 December 2010, CIMMYT. Egypt Map. Development of wheat area, productivity and production in Egypt (1981 – 2008). Wheat in Egypt. Food for man and fodder for animal.

malo
Download Presentation

Khaled F M Salem

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Application of Biotechnology Tools in Egyptian Bread Wheat Breeding Khaled F M Salem Wheat Science to textbooks, 5-10 December 2010, CIMMYT

  2. Egypt Map

  3. Development of wheat area, productivity and production in Egypt (1981 – 2008)

  4. Wheat in Egypt • Food for man and fodder for animal. • Production: 7.5 m. t. (2009). • Area: 1.2 m.ha. • Consumption: 15.0 m.t. • Gap: 7.5 m.t.

  5. Wheat Research Interest • Breeding Program. • Genetic Resources. • Biotechnology Component. • Wheat Biotic and Abiotic.

  6. Genetic Engineering Research Institute (GEBRI) Specific objectives: • Generation of useful somaclonal variation via tissue culture. • Rapid fixation of useful genetic variation into homozygous lines in one generation via anther culture-derived doubled haploids. • Improving parental selection for crossing via molecular genotyping and measuring genetic diversity. • Identification of molecular markers linked to abiotic stress tolerance, particularly heat, salinity and drought. • Implementation of marker-assisted selection in breeding efforts for durable rust resistance and better salinity and drought tolerance.

  7. Current activities • Generation of useful somaclonal variation: • Selected lines resistance to rusts diseases and tolerant to salinity stress. • Use somaclonal variation to produce rusts resistant plants and drought tolerant.

  8. Molecular marker activities • Optimization of DNA extraction methods, high yield, high quality genomic DNA, without use of liquid Nitrogen. • Optimization of PCR-based molecular marker systems: • Random amplification markers; RAPDs, ISSRs • Specific amplification markers; STS, SSRs, SNP and ESTs.

  9. Gene and Genome Mapping Identification and mapping quantitative trait loci for biotic and abiotic stresses in wheat (Triticum aestivum L.) Genetic Diversity Evaluation of genetic diversity in Egyptian wheat varieties using microsatellite markers. Assessing wheat (Triticum aestivum L.) genetic diversity using morphological characters and microsatellite markers. MAS Allelic detection at the microsatellite Xgwm261 locus linked to the Rht8 dwarfing gene in wheat. Prediction of Heterosis and Combining Ability in Early Generation Relationship between genetic diversity based on DNA markers with heterosis and combining ability in diallel cross of bread wheat (Triticum aestivum L.). • Main Molecular Marker Activities

  10. Assessing wheat (Triticum aestivum L.) genetic diversity using morphological characters and microsatellite markers Wheat, a self-pollinating crop, has been bred for a wide array of specific end-use quality traits and various adaptive characteristics. Knowledge of genetic diversity in a crop species is fundamental to its improvement. Evaluation of genetic diversity levels among adapted, elite germplasm can provide predictive estimates of genetic variation among segregating progeny for pure-line cultivar development (Manjarrez-Sandoval et al. 1997).

  11. The use of molecular markers for the evaluation of genetic diversity is receiving much attention. RAPDs (Joshi and Nguyen 1993), RFLPs (Siedler et al. 1994; Kim and Ward 2000) AFLPs (Barrett and Kidwell 1998) STS (Chen et al. 1994) and ISSRs (Nagaoka and Ogihara 1997). However, most of these marker systems show a low level of polymorphism in wheat, especially among cultivated lines and/or cultivars (Chao et al. 1989; Devos and Gale 1992).

  12. Microsatellites are one of the most promising molecular marker types able to identify or differentiate genotypes within a species. Narrow genetic diversity is problematic in breeding for adaptation to biotic and abiotic stresses as well as increasing in yield productivity. Therefore, it is necessary to investigate the genetic diversity in wheat germplasm in order to broaden the genetic variation in future wheat breeding programme.

  13. The objectives of this study were to (i) use SSRs to assess levels and patterns of genetic variability among wheat genotypes. (ii) use wheat microsatellite markers for the characterization and assessment of the genetic diversity of wheat genotypes.

  14. Table : Name, origin and pedigree of the wheat genotypes used in this study.

  15. Table: Gene diversity for fifteen microsatellite loci

  16. Fig. Dendrogam analysis of genetic relationships based on gSSRs diversity

  17. Table: Similarity matrix based on microsatellite markers.

  18. summary This study using wheat microsatellite markers revealed considerable amount of genetic diversity among seven wheat genotypes. The WMS data can be used in selecting diverse parents in breeding programme and in maintaining genetic variation. Also, this study also shows that analyzing higher numbers of genotypes may not add much practical value to a general plant improvement program, unless a specific crossing program is aimed towards the improvement of specific traits. It is therefore suggested that a focused breeding scheme should be adopted.

  19. ALLELIC DETECTION AT THE MICROSATELLITE Xgwm261 LOCUS LINKED TO THE Rht8 DWARFING GENE IN WHEAT Plant height reduction is one of the single most important adaptations introduced into cereals by breeders over the past century (Reynolds and Borlaug 2006). Tall wheat cultivars are more prone to lodging, particularly when grown in favorable environments, whereas semi-dwarf cultivars are shorter, less prone to lodging and usually partition more dry matter to the grain (Waddington et al., 1986). The use of dwarfing genes to reduce plant height and improve yield potential has been one of the major strategies in breeding program. Related to their response to exogenously applied gibberellins (GAs), dwarf genes can be classified into two categories insensitive or sensitive to exogenous gibberellic acid (GA) (Gale and Youssefian, 1985; Slafer et al., 1994; Calderini et al., 1995, Borner et al., 1996). Plant carrying GA insensitive dwarfing genes can be recognized by applying a weak solution of GA to germinating seedlings (Gale and Gregory, 1977).

  20. The aims of this work were (i) to analysis the allelic variation in Xgwm261 microsatellite locus and (ii) to detect the Rht8 gene in some Egyptian and exotic wheat varieties.

  21. Marker assisted selection MAS Table (1): Name andorigin of the wheat genotypes used in Rht8.

  22. Table ( 3): Allele size, CL and SL under control and GA3 test

  23. Table (3): Coleoptile length and seedling length mean performance under control and GA3 test for alleles at Xgwm261 locus.

  24. Figure (1): Percentage distribution of 6 alleles for the microsatellite locus Xgwm261 in the wheat varieties.

  25. Conclusions It was found that, a 192-bp allele at microsatellite locus Xgwm261 is associated with reduction in plant height. Therefore, a 192-bp allele at this locus is always diagnostic for the height reducing gene Rht8 and its presence is sufficient to determine whether a particular cultivar carries Rht8 or not. In addition, the Egyptian wheat varieties were has 192-bp allele and carry Rht8. So this will reflects the importance of Rht8 and involve it in Egyptian breeding programs.

  26. Thank you for your attentions

More Related