Virulence of broomrape affecting sunflower in Volgograd and Rostov regions

Broomrape races E, F, G, H were found out on sunflower in Volgograd and Rostov regions. Sample of broomrape seeds from Volgograd region were less virulent in comparison with the same one from Rostov region. There is diversity on broomrape virulence in different areas of investigated regions. The broomrape samples from the same area also can differ significantly by its virulence. It is important for placement of sunflower assortment which is differed with gens of resistance. It is also meaningful for sunflower breeding on resistance.