Phytosociology and genetic diversity of Prunus Species (wild and cultivated) growing in different agro-ecological zones of Muzaffarabad division, Azad Jammu and Kashmir, Pakistan.

Abstract

Genus Prunus is one of the most economically important genus of Rosaceae family with worldwide distribution. The present study was conducted to investigate the phytosociology and genetic diversity of genus Prunus and associated species in Muzaffarabad Division, Azad Jammu and Kashmir. Phytosociological data were obtained from different ecological zones by using systematic quadrat sampling following standard protocols. Results were analyzed by using multivariate ordination techniques to correlate species data with environmental variables. A total of 362 species belonging to 239 genera and 96 families were recorded from 21 selected sites. Poaceae was the leading dominant family with 37 genera and 48 species followed by Rosaceae, Asteraceae and Ranunculaceae. A total of five species of genus Prunus were recorded from studied sites with Prunus mira as dominant followed by P. armeniaca, P. domestica, P. avium and P. cerasus respectively. Megaphanerophytes was the dominant life form with 29.25 percent followed by hemicryptophytes, nanophanerophytes and therophytes, respectively. Results of leaf size spectrum revealed microphylls as dominant with 48.13 percent followed by leptophylls and nanophylls respectively. Average value of species diversity at the studied sites were 2.80; Species richness was 1.17 whereas the equitability was found to be 0.74. Cluster analysis revealed six identifiable plant clusters based upon correlation matrix. Principal component analysis verified the results of phytosociological studies showing the dominance of specific keystone species at the specific sites. Genetic diversity of genus Prunus was analyzed using a set of 39 SSR markers. A total of 96 accessions belonging to six different species of genus Prunus were used for computing various parameters of genetic diversity. The six species of genus prunus exhibit significant levels of genetic variation. Total number of observed alleles was 217 with an average of 18 alleles per locus. Average value of gene diversity between loci was 0.88 with minimum of 0.56 and maximum of 0.91. Average frequency for major alleles was determined as 0.28 with a maximum value of 0.64 in the BPPCT006 locus and minimum of 0.16 at CPPCT022. The size of DNA fragments among all loci ranged from 100-316 bp. The average value of polymorphism information content for all the loci was 0.826 with a maximum of 0.911 for the locus CPPCT022 and minimum 0.53 for the locus BPPCT006. Observed heterozygosity ranged from 0.11-0.812 with an average of 0.471 whereas expected heterozygosity varied from 0.561-0.916 with an average of 0.84. Unweighted pair group mean average method (UPGMA) results showed significant grouping among genus Prunus accessions collected from different ecological zones representing the environmental impact on genotypes. Results revealed that Prunus local land races exhibit significant genetic variations which needs to be further evaluated by employing advanced techniques. Therefore, extensive evaluation using modern research tools is recommended for conservation efficiency and improvement of germplasm management.