Immature zygotic embryos of sunflower line 197 В were treated with ultrasonic before plating to embryo culture medium. Some mutant plants were isolated and self-pollinated for several generations. New sunflower forms with inherited phytopathological, morphological and biochemical changes were obtained through selection and self-pollination. Reduction and increasing were observed for the character plant height. Positive and negative changes according to the control line were observed for the character 1000 seed weight. Significant increasing in the mean arithmetic value were estaЫish in characters seed weight, seed thickness and stem diameter. The mutation for resistance to the local population of Orobanche ситапа (race А-Е) was obtained from the susceptible Bulgarian control line 197 В.
Developing mutant B lines in sunflower (helianthus annuus L.) through induced mutagenesis