从油菜(Brassicanapus L.cv.Topas)裂外壁小孢子培育出胚状体与小植株

Embryoid Formation and Plantlet Regeneration from Exine-dehisced Microspores in Brassica napus L. cv. Topas

油菜 (Brassica napus L.cv.Topas)小孢子经高温 (32℃ )预培养导致外壁开裂 ,形成裂外壁小孢子。微室饲养培养技术结合定位追踪观察证实裂外壁小孢子具有胚胎发生能力。 33.3%的裂外壁小孢子能启动细胞分裂 ,其中13.3%的裂外壁小孢子能持续分裂 ,并遵循胚胎发生途径。与完整小孢子不同 ,第一次分裂既有均等分裂 ,亦有不均等分裂 ,两者均能导致胚胎发生。将已分化的胚状体转移至固体培养基上 ,可经二次胚胎发生或直接再生小植株。

By preculture in the temperature of 32℃, the exine of microspores in Brassica napus L. cv. Topas could be induced to dehisce, forming so called exine dehisced microspores. With the aid of a microculture and feeder cell system and tracing the development of individual mocrospores, it is proved that exine dehisced microspores have the capacity of embryogenesis. 33.3% of the exine dehisced microspores divided, and among them 13.3% developed into embryoids. Quite different from the development of wall intact microspores, the first division of exine dehisced microspores could be symmetric or asymmetric. Both kinds of microspores could lead to embryogenesis. After been transferred to solid medium, the mature embryoids could go on developing, forming secondary embryos or regenerating plantlets directly.