Molecular variation and genetic relationships among Iranian and foreign pistachio cultivars using gene-targeted CAAT box-derived markers

The objectives of this research were study of genetic diversity in Iranian and foreign pistachio cultivars using CBDP markers and the efficiency of these markers in differentiation and grouping of cultivars.

In this research, genetic diversity of 73 cultivars (63 Iranian and 10 foreign cultivars) was evaluated using 25 CBPD primers.

The results showed that, the bands polymorphism for Iranian and foreign cultivars was 77.56% and 67.80%, respectively. The PIC mean for CBPD markers was 0.76 and all CBDP primers had a high ability to separate pistachio cultivars. The MI mean for CBDP primers was 2.65 and CAAT2 primer showed the highest MI (8.52) value. Analysis of molecular variance determined 4% inter-group diversity and 96% intra-group diversity for studied genotypes. Gst value 0.04 verified low inter-group diversity as well. Nm value 11.03 showed the gene flow between foreign and Iranian pistachio cultivars. Iranian cultivars had higher values than foreign cultivars in terms of both Nei and Shannon gene diversity indices as well. Cluster analysis using Jaccard matrix and UPGMA method was performed and the results showed, the average of similarity coefficient between cultivars was 0.68 and the pistachio cultivars were divided in three main groups, in which the main groups were subdivided into several subgroups. The principal coordinate analysis also confirmed the result of the cluster analysis.

In conclusion, the use of CBDP markers is suitable for studying the genetic diversity of pistachio cultivars. Also, the efficiency and differentiation power of CBDP primers was confirmed due to the high mean of PIC and MI.