African Journal of

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12227

Full Length Research Paper

Evaluation of genetic diversity in Pyrus germplasm native to Azad Jammu and Kashmir (Northern Pakistan) revealed by microsatellite markers

  Maqsood Ahmed1*, Muhammad Akbar Anjum2, Muhammad Qayyum Khan3, Mohammad Jamil Ahmed1 and Stephen Pearce4  
  1Department of Horticulture, Faculty of Agriculture, Rawalakot, University of Azad, Jammu and Kashmir Pakistan. 2University College of Agriculture, Bahauddin Zakariya University of Multan, Pakistan. 3Department of Plant Breeding & Molecular Genetics, Faculty of Agriculture, Rawalakot, University of Azad,Jammu and Kashmir Pakistan. 4School of Life Sciences, Department of Biological Sciences, University of Sussex, Brighton, East Sussex, UK.  
Email: [email protected]

  •  Accepted: 30 September 2010
  •  Published: 06 December 2010



Pyrus germplasm of Azad Jammu and Kashmir (56 accessions) and East Malling Research Station Kent, UK (8 reference cultivars) were characterized using 12 microsatellite markers assessing genetic diversity. In total, 9 primer pairs revealed 106 putative alleles that ranged from 7 to 19, averaging 11.8 alleles per locus. The size of amplified fragments ranged between 83 and 328 bp, while polymorphism information content varied from 0.780 to 0.918, averaging 0.844. Similarity coefficients ranging from 0.00 to 1.00 was observed in KT53 (Btung) and between BG21 and MZ26 which are both locally called ‘Kotharnul’. UPGMA cluster analysis of similarity grouped all the genotypes into 3 main clusters, two identical groups and four accession/varieties which fell independently based on their pedigree and geographical origin. Similarity data illustrated an unambiguous genetic diversity and relationship among different ecotypes and varieties in a dendrogram. The most phenotypically variable accessions from different geographical regions fell into two homogeneous groups, ‘A ‘and ‘B’, with some branched accessions. Among reference varieties, 5 distantly fell into one cluster, 2 branched with the lowest affinity to each other and ‘Pendula’ existed independently showing the highest diversity. The local accession KT53 (Btung), representing the highest genetic diversity to all genotypes, had a unique genetic base.


Key words: Genetic diversity, gene pool, simple sequence repeat (SSR), pear.



Abbreviations: PIC, Polymorphism information contents; CTAB, cetyl trimethyl ammonium bromide; SSR, simple sequence repeats; PCR, polymerase chain reaction; RFLP, restriction fragment length polymorphism; AFLP, amplified fragment length polymorphism; RAPD, random amplified polymorphic DNA.