Genetic variation of the durum wheat landrace Haurani from different agro-ecological regions

Abstract

The durum wheat landrace Haurani (Triticum durum Desf.) is grown under contrasting climatic regions of Syria from Deir Ezzor, in the North-East (230 m altitude, 150 mm mean annual rainfall), to Qunaytra, in the South-West (1060 m altitude, 825 mm mean annual rainfall). In order to assess the genetic variation between and within Haurani populations, samples from eight provinces of Syria (Dara'a, Damascus, Qunaytra, Deir Ezzor, Hassakeh, Aleppo, Homs and Hama) were analysed by RFLPs and seed storage proteins of glutenin subunits as markers. The analyses showed the presence of genetic polymorphisms in all populations with the highest values in those from Homs and Hassakeh. Moreover, the results point out differences in genetic distances between populations; some populations were further apart, such as Damascus and Aleppo, whereas others were closer to each other, for instance Homs and Hama. Cluster analysis identified two distinct groups of populations, characterized by geographical proximity, with similar rainfall and altitude. It is suggested that the similarity of landraces at locations close to each other might be the result of more frequent seed exchanges between farmers or of gene flow due to 5% estimated outcross rate of Haurani.

Using Bayesian and Eigen approaches to study spatial genetic structure of Moroccan and Syrian durum wheat landraces

“…The genetic diversity found in the Moroccan and Syrian landraces was higher than the diversity found by Moragues and colleagues [27] for a group of Mediterranean durum landraces using low and high molecular weight loci. Moroccan and Syrian durum wheat landraces hold large genetic variability and considerable number of alleles with the probability of having some of these alleles associated with stress tolerance, yield, and/or grain quality [1,2]. The spatial autocorrelation (SAU) applied to an individual allele did not express the global spatial structure we have in our data [15].…”

“…These Mediterranean landraces possess desirable traits related to resistance to drought, heat, and cold, such as early vigor, long peduncle, and high fertile tillering capacity; and to grain qualities required for different durum wheat end products. In the Eastern Mediterranean basin, Syria is considered as one of the most important habitats for Triticum wild relatives and landraces of durum wheat; and where some landraces are still grown by the farmers such as Haurani and Hamari [2]. Also in the Western Mediterranean basin, Morocco durum wheat landraces are grown in different agro-ecologies, altitudes, latitudes, and water regimes; and carry tolerance/resistance to various abiotic and biotic stresses [1,2].…”

“…In the Eastern Mediterranean basin, Syria is considered as one of the most important habitats for Triticum wild relatives and landraces of durum wheat; and where some landraces are still grown by the farmers such as Haurani and Hamari [2]. Also in the Western Mediterranean basin, Morocco durum wheat landraces are grown in different agro-ecologies, altitudes, latitudes, and water regimes; and carry tolerance/resistance to various abiotic and biotic stresses [1,2]. Multi-allelic microsatellite markers can be employed for the determination of genetic struc-ture and spatial adaptation of these landraces.…”

Temporal variation of diversity in Italian durum wheat germplasm

“…The level of molecular variation in durum wheat, as observed in common wheat (Gale et al 1990), is low (Autrique et al 1996;Eujayl et al 2001;Pagnotta et al 2004). However, at molecular level, storage proteins resulted more efficient than RFLPs and RAPDs in distinguishing Italian durum wheat cultivars from landraces (Figliuolo and Spagnoletti Zeuli 2000).…”

“…Genetic markers have been used successfully in assisting crop selection and monitoring evolutionary factors (Donini et al 1998(Donini et al , 2000Christiansen et al 2002;Pagnotta et al 2004). …”