The ultrastructural features of microsporogenesis in sunflower Helianthus annuus L. with RIGO type of cytoplasmic male sterility

Microsporogenesis in fertile and CMS RIG0 analogs of inbred sunflower line VIR 109 was investigated by light and electron microscopy. Differences in the ultrastructure of the tapetum cells and microsporocytes between the normal pollen development and its degeneration were detected. Based on the literature and our own research, a comparative analysis of the cytologic features that characterize the abortive microsporogenesis in forms with CMS and RET1 RIG0 was conducted.