Variation between and within broomrape (Orobanche) species revealed by RAPD markers.

The variation among and within natural populations of broomrape (Orobanche) species, a parasitic flowering plant, was determined by using random amplified polymorphic DNA (RAPD) markers. Interspecific variation was determined among five major broomrape species in Israel: O. aegyptiaca, O. mutelii, O. cernua, O. cumana and O. crenata. The pattern of interspecific variability and genetic distances observed in this study was in agreement with previous taxonomical characterization based on morphological differences among the species. Intraspecific variation was determined for O. aegyptiaca and O. crenata. Whereas 99 per cent of the amplified fragments were polymorphic among the species, only 23 per cent and 21 per cent, respectively, of the amplified fragments were polymorphic within O. aegyptiaca and O. crenata. For both species, each individual plant had a unique genotype based on a combined pattern of all the markers. No evidence was obtained for host differentiation for O. aegyptiaca and O. crenata and for regional differentiation for O. crenata.