Development, characterization and use of genomic SSR markers for assessment of genetic diversity in some Saudi date palm (Phoenix dactylifera L.) cultivars

AbstractGenetic variability in date palm genotypes collected from different regions of southern Tunisia was analyzed using a Start Codon Targeted (SCoT) marker system. Thirty-one accessions collected from three locations were investigated. One hundred and nine amplicons were produced among which 84 % were polymorphic. The PIC value and the Rp values testified of the efficiency of used primers. The percentage of polymorphic loci (Pp) varied from 44.57 to 83.70 %, Nei‘s gene diversity (H) from 0.175 to 0.273 with a mean of 0.228, and Shannon‘s information index (I) values ranging from 0.257 to 0.409 with an average value of 0.338 were illustrated. The Tunisian date palm populations exhibited high genetic differentiation (GST = 0.319) and gene flow (Nm = 1.063). The AMOVA analysis presented 70 % of the variation within the population and 30 % of the variation between them. Phylogenetic analysis and the Bayesian clustering approach also revealed high genetic variation among genetic variants with a net divergence of the wild insular population of Kerkennah from other cultivars. The present investigation suggests the effectiveness of the SCoT marker system to estimate the genetic diversity of Phoenix dactylifera genotypes.

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Molecular characterization of some landraces and varieties of Date palm (Phoenix dactylifera L.) from Afar region of Ethiopia using ISSR markers

10.21203/rs.2.10762/v1 ◽

2019 ◽

Author(s):

Meera Indracanti ◽

Dawud Takele Mekonnen ◽

Mesfin Tsegaw

Keyword(s):

Genetic Diversity ◽

Date Palm ◽

Polymorphic Information Content ◽

Phoenix Dactylifera ◽

Issr Markers ◽

Snp Markers ◽

Discrimination Power ◽

Information Index ◽

Phoenix Dactylifera L ◽

Afar Region

Abstract Back ground Date palm (Phoenix dactylifera L.) is one of the oldest fruit trees in hot arid region of the world including North Africa. In some areas of Afar region of Ethiopia, date palm grow as landraces, are in danger due to introduction of improved cultivars. Present study was carried out to fill knowledge gap about molecular diversity of this crop in Afar region. Molecular studies of 5 landraces and 3 introduced cultivars of date palm from Afar region of Ethiopia were tested using 21 randomly selected ISSR primers for amplification and polymorphism detection using genomic DNA. ISSR markers across 8 date palm varieties were scored for their presence (1) or absence (0). Shannon's Information index (I) and polymorphic information content (PIC) were analyzed by popGENE 32 and online PIC calculator respectively. Results 17 out of 21 ISSR markers used for this study produced a total of 557 scorable DNA fragments with average of 33.52 per marker and 61.68, 43.93 and 68.22% polymorphism were obtained within local landraces, introduced varieties and among all samples respectively. The genetic distance among all samples ranged from 0.1402 to 0.5953; and the dendrogram separated date palm varieties into seven clusters. ISSR markers used for this study have high discrimination power and the average values of Shannon's information index and PIC were 0.318 and 0.76 respectively. Conclusion Genetic diversity was observed among all date palms studied in this investigation. To have better understanding on genetic diversity of date palm in the Afar region, further research should be done using SNP markers and landraces should be registered.

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