Anatomical Observation of Anther Development of a New Thermo-Sensitive Genic Male Sterile Line SP2S in Brassica napus L.

SP2S is a new type thermo-sensitive genic male sterile line of Brassica napus breeding in Northwest AF University.The anatomical characters of pollen and the anther development of SP2S at different stages were compared with its near isogenic line SP2F by semi-thin sections and scan electronic microscopy.The result indicated that the anther abortion occurred at the stage of meiosis and the anther completely aborted at the later stage of uni-nucleate.The tapetal cells were highly vacuolated and deformed at the stage of meiosis.Callose around the tetrads couldn't be degradated timely,which made the microspores adhesion with each other.And then the microspores didn't form the extine normally.The cytoplasm of pollen cells decayed gradually and at last became empty.These evidences obviously indicate that SP2S is probably a new thermosensitive male sterile line which is different from the previously materials.