Lines resistant to Plasmopara halstedii Phomopsis helinthi Septoria helianthi and Orobanche cumana (race E and G) were obtained from the Bulgarian susceptible fertility restorer lines 2574 R 147 R 374 R 381 R 377 R American line RHA-857 and Bulgarian line with normal cytoplasm 197 B. Lines were developed using embryo culture method in combination with ultra sonic and gamma irradiation at sunflower immature zygotic embryos. All investigated lines possessed 100% resistance to diseases and parasite Orobanche . Some of the new lines showed very good combining ability. Line 12002 R developed through embryo culture method at immature zygotic embryos in combination with gamma irradiation at dose 8 Gy is paternal component of commercial hybrid Rada. Line 12003 R developed through embryo culture method at immature zygotic embryos in combination with ultra sonic at dose 25.5 W cm −2 for 1 min is paternal component of commercial hybrid Yana. Hybrids Rada and Yana possessing immunity to parasite Orobanche cumana race E and G respectively; immunity to Plasmopara helianhi ' races 300 330 700 and 731; resistance to Phomopsis ; immunity to Macrophomin a and tolerance to Phoma . Our results showed that mutagenesis in sunflower can be successfully applied to develop new lines suitable for use as parental components of new hybrids.