Review of investigation of variability of nad1 gene intron B/C of mitochondrial genome in Scots pine (Pinus sylvestris L.)

Background and Purpose: Scots pine (Pinus sylvestris L.) is the most extensively distributed pine, covering the whole Eurasian continent. The detection of genetic variability of Scots pine is of greate importance from the evolutionary point of view as well as for genetic conservation. Mitochondrial genome in Scots pine is maternally inherited and dispersed through seeds. Molecular studies have indicated high genetic diversity in Scots pine genome, allowing the detection of variation between and within population. Mitochondrial genome possesses variable regions in the gene encoded NADH dehydrogenase. The variable region is nad1 B/C intron. The different haplotypes of nad1 B/C intron allowed confirming the Iberian refugia in Holoecen and confirming the genetic diversity between different stands of Scots pine in Poland. The purpose of this study was to find out the genetic variability of nad1 B/C intron in two International Scots pine provenance experiments and native Scots pine provenance in Croatia in order to detect multiple origin and haplotype variation between provenances. Material and Methods: The samples of Scots pine were taken from two International experiments of provenances, one established in Croatia (22 provenances) and the other established in Hungary (20 provenances) and Croatian native provenance (Forest office Vrhovine, Forest administration Gospi}). The samples of needles were collected from randomly chosen trees of each provenance. Eight samples per provenance were collected for haplotype analyses. DNA was extracted and amplified with specific primers for nad1 B/C intron of the mitochondrial DNA. PCR products were analyzed using agarose gel electrophoresis and capillary electrophoresis on the bioanalyzer Agilent 2100. Results and Conclusion: We investigated samples from 42 provenances of Scots pine that originated from a broad range in Eurasia and were included in two international provenance experiments, and samples from native Croatian population. A total of 344 individual trees of Scots pine were analyzed. The data were analyzed by agarose gel electrophoresis and by capillary electrophoresis. We did not detect variability in mitochondrial nad1 B/C region in analyzed samples. All analyzed samples were haplotype a. Based on our data, we could conclude that none of the tested samples originated from the Iberian glacial refugia. All tested samples could have the origin in glacial refugia placed in Mediterranean, Balkan region or in the northeastern Europe. More variable region of the nuclear DNA and the mitochondrial DNA should be tested on a greater number of samples to obtain more informative data. NEVENKA ]ELEPIROVI] MLADEN IVANKOVI] MARIJA GRADE^KI-PO[TENJAK LASZLO NAGY ATTTILA BOROVICS SANJA NOVAK AGBABA TIBOR LITTVAY 1 Croatian Forest Research Institute Cvjetno naselje 41 10450 Jastrebarsko Croatia Forest Research Institute Experimental Station Sarvar Varkerulet 30/a 9600 Sarvar Hungary Correspondence: Nevenka ]elepirovi} Croatian Forest Research Institute Cvjetno naselje 41 10450 Jastrebarsko, Croatia E-mail: nevenkac@sumins.hr