Development of female reproduction structures and apomixis in some cms lines of sunflower

SUMMARY Under natural conditions, only cross-pollination is typical for sunflower. The apomixis phenomenon was hardly observed in genre Helianthus L. Development of embryo sac at sunflower goes according to Polygonum -type, embryo formation goes according to Asterad -type ( Senecio -variation). On plants of cms -lines a series of experiments on interspecific hybridization was carried out. As a result a number of anomalies in development of female reproductive system were investigated, including such apomixis phenomena as an apospory and integumentary embryony. In some ovule was noted total absence of embryo sac. All ovule structures were normally formed, but on the place of embryo sac some small and 1-3 large cells were found. Lack of the main embryo sac and formation of additional aposporous embryo sacs could be observed at the same time in the same ovule.