A comparison of impact of herbicides of imidazolinone and sulfonylurea groups on broomrape in breeding of confectionary sunflower varieties

Annually, confectionary sunflower varieties occupy from 300 to 500 thousand hectares in the Russian Federation. The varieties developed last years (Karavan, Konditer, SPK Plus) are able to form high yields of seeds in the heavy agroclimatic conditions. At the same time, spreading of the new more virulent races of broomrape causes the significant decrease in yield of confectionary varieties. One of the effective methods of broomrape control is chemical one. The experiment was conducted on isolated plot in field after introducing the seeds of the virulent broomrape races in soil. Treatment with herbicides in recommended doses was conducted using backpack sprayer. The level of broomrape control with imidazolinons is significant and equitable to action of a gen of broomrape resistance Or7 by both percentage and a level of infection. Tribenuron-methyl repressed a level of infection under high infestation with broomrape in the studied confectionary sunflower varieties.