The interpopulation genetic differentiation of Orobanche cumana Wallr. from Russia, Kazakhstan and Romania by using molecular genetic markers

The molecular genetic diversity of broomrape populations of O.cumana, parasitizing on sunflower in Russia, Romania, and Kazakhstan, by using codominant microsatellite markers was studied. During cluster analysis the broomrape populations were divided into two clusters, regardless of their racial composition. One cluster grouped 19 samples from Russia and Kazakhstan, representing one gene pool, and the other - 5 populations from Romania, combined into second gene pool. The genetic distance between clusters according to Nei was 0.137. The analysis of molecular variance AMOVA revealed that 22 % of the overall dispersion was due to the differences among the genetic pools and the most part of dispersion - 78 % - was due to the differences between individuals within each genetic pool. The pairwise comparisons made using Wright’s F statistics showed that the differences between these two genetic pools are sufficient (Fst = 21.9 %) to state the existence of a small genetic differentiation between them. Descriptive population genetic statistics for each of the two pools showed that the broomrape populations from the former Soviet Union countries are characterized by a higher level of intrapopulation diversity than the populations from Romania. Mo lecular genetic differences between broomrape populations parasitizing on sunflower on the post-Soviet territory and in Romania were insignificant. Possible reasons for these results are being discussed.