Genetic diversity and population structure of Iranian pistachio (Pistacia vera l.) cultivars

Abstract

Iran has a rich pistachio germplasm, thereby, the diversity and number of Iranian pistachio cultivars is unique in the world. Genetic diversity is crucial for sustainable use of genetic resources and conservation. As one of the oldest nut crops in human history, pistachio nuts have a high nutritional value and are commercially important. In the present study, the genetic variation of pistachio genotypes was investigated by nuclear ISSR markers. In this study, genetic relationships among 11 cultivars was assessed by using 12 inter simple sequence repeat (ISSR) primers. The total of 53 bands of which 44 (83%) were polymorphic were amplified by the 12 primers, an average of 4.4 bands per primer. The total number of amplified fragments was between 2 to 6 and the number of polymorphic fragments ranged from two to six. The amplified allele sizes ranged from 300 to 1600 bp. Pair-wise genetic similarity coefficients varied from 0.70 to 0.95. The UPGMA dendrogram differentiated the genotypes into two major clusters. The Mantel test showed correlation between genetic and geographical distance. AMOVA revealed a significant genetic difference among cultivars and showed that 35% of total genetic variation was due to within- cultivars diversity. The present results may be used for the conservation, core collection and future breeding of the pistachio.