Title : Assessment of the genetic diversity of Apple (Malus x domestica Borkh.) Cultivars grown in eastern Algeria using microsatellite markers
Abstract:
The diverse germplasm of any crop species represents an important genetic resource for mining genes or alleles necessary to meet future nutritional and disease resistance needs. A total of 6 SSR markers were used to elucidate genetic diversity among eighty-three apple accession for the first time in the Batna and Khenchela provinces, the two most important apple producing regions of Eastern Algeria.
The aim of this study is to investigate the genetic identity of Algerian apple cultivar and their relationship to the history of here propagation in these 2 regions to identify potentially valuable clones who is essential for the designation of the best populations to select for in situ conservation.
A total of 58 polymorphic fragments were obtained, a high level of genetic diversity was observed in these 12 cultivars with a total of 53 alleles obtained by 6 SSR primers, between 7 (CH01F02) and 11 (CH02d08) alleles per loci with an average of 5.25 among the 63 accessions studied in total. The Jaccard’s similarity coefficient and cluster analysis using UPGMA algorithm were used to allow deducing the genetic relationship between the 63 analyzed genomes. The genotypes were organized into two main groups. The AMOVA results demonstrated that 72% of the total diversity was retained within either varieties groups, while 28% of the variance was attributed to differences among groups of varieties. The Bayesian analysis revealed a structuring of 63 accessions into four distinct subpopulations based on sharp peak of Delta K Evanno which confirmed that the most relevant partition was at k = 4.
The differences in genetic diversity can be mostly attributed to the distinct and diverse geographical origins of the domesticated apples, the high accuracy of these SSR loci in distinguishing accessions highlights their utility in active germplasm management and bridging the gap between national and local collections of apple
