title: The genetic structure of wild Orobanche cumana Wallr. (Orobanchaceae) populations in eastern Bulgaria reflects introgressions from weedy populations.
abstract: Orobanche cumana is a holoparasitic plant naturally distributed from central Asia to south-eastern Europe, where it parasitizes wild Asteraceae species. It is also an important parasitic weed of sunflower crops. The objective of this research was to investigate genetic diversity, population structure, and virulence on sunflower of O. cumana populations parasitizing wild plants in eastern Bulgaria. Fresh tissue of eight O. cumana populations and mature seeds of four of them were collected in situ on wild hosts. Genetic diversity and population structure were studied with SSR markers and compared to weedy populations. Two main gene pools were identified in Bulgarian populations, with most of the populations having intermediate characteristics. Cross-inoculation experiments revealed that O. cumana populations collected on wild species possessed similar ability to parasitize sunflower to those collected on sunflower. The results were explained on the basis of an effective genetic exchange between populations parasitizing sunflower crops and those parasitizing wild species. The occurrence of bidirectional gene flow may have an impact on wild populations, as new physiological races continuously emerge in weedy populations. Also, genetic variability of wild populations may favour the ability of weedy populations to overcome sunflower resistance mechanisms.
authors.affiliation: Institute for Sustainable Agriculture (IAS-CSIC), Finca Alameda del Obispo, Avenida Menéndez-Pidal s/n, 14004 Córdoba, Spain.
authors.forename: Rocío
authors.initials: R
authors.lastname: Pineda-Martos
authors.affiliation: Department of Agricultural and Forestry Sciences and Resources, University of Córdoba, Campus de Rabanales, Edificio Celestino Mutis, Carretera de Madrid Km 396, 14071 Córdoba, Spain.
authors.forename: Antonio J
authors.initials: AJ
authors.lastname: Pujadas-Salvà
authors.affiliation: Institute for Sustainable Agriculture (IAS-CSIC), Finca Alameda del Obispo, Avenida Menéndez-Pidal s/n, 14004 Córdoba, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Fernández-Martínez
authors.affiliation: Department of Botany, Agricultural University of Plovdiv, 12 Mendeleev, 4000 Plovdiv, Bulgaria.
authors.forename: Kiril
authors.initials: K
authors.lastname: Stoyanov
authors.affiliation: Institute for Sustainable Agriculture (IAS-CSIC), Finca Alameda del Obispo, Avenida Menéndez-Pidal s/n, 14004 Córdoba, Spain.
authors.forename: Leonardo
authors.identifier: 0000-0003-4998-9406
authors.initials: L
authors.lastname: Velasco
authors.affiliation: Institute for Sustainable Agriculture (IAS-CSIC), Finca Alameda del Obispo, Avenida Menéndez-Pidal s/n, 14004 Córdoba, Spain.
authors.forename: Begoña
authors.initials: B
authors.lastname: Pérez-Vich
mesh_terms: D002031:Bulgaria; D051456:Gene Flow; D006368:Helianthus / Q000469:parasitology; D031670:Orobanchaceae / Q000145:classification / Q000235:genetics* / Q000502:physiology*