Assessment of genetic structure in healthy and declined populaation of Quercus brantii Lindl. using EST-SSR and ISSR markers

Abstract

Drought as a primary factor along with other secondary factors such as outbreaks of pests and diseases as well as fires in recent decades in the Zagros forests have destroyed many trees, especially Quercus brantii as dominant tree species in Zagros forests.. So, genetic variability of 51 healthy and declined trees of Quercus brantii in Khaeez forests was evaluated by two molecular markers; 4 and 5 primers of EST-SSR and ISSR markers, and 28 and 15 band fragments were amplified, respectively. Results of ISSR markers showed that polymorphism percentage and genetic diversity of all Q. brantii trees were 95.83% and 0.40, respectively and genetic diversity value was higher in healthy trees population than declined. Also, only 6.82 of genetic differentiation was observed between two populations of healthy and declined trees based on molecular variance analysis (AMOVA). ISSR1 showed the highest accuracy (83.3%) for distinctive healthy and declined trees compared to other ISSR primers. Results of EST-SSR also showed higher heterozygosity in healthy trees and there was heterozygote deficiency Q. brantii by using all primers. Also, genetic differentiation was very low between healthy and declined trees and FIR031 showed the highest value compare to other primers. In conclusion, results suggest that genetic diversity had an important role in adaptation to drought stress of healthy Q. brantii trees. Moreover, using appropriate markers for identifying mother trees with high genetic value can be considered for improving the reforestation.

Keywords

• adaptation
• heterozygoty
• oak dieback
• rehabilitation
• zagros forests