一种新型无花瓣油菜突变不育系花器官的形态解剖研究

在自育的甘蓝型油菜(Brassica napus)无花瓣品系AP197中, 发现并育成由4对隐性核基因控制的无花瓣油菜突变不育系AMS971。AMS是一种雄蕊心皮化为不结实的假性雌蕊而引起的新的雄性不育类型, 不育性非常彻底, 其植株形态特征与AP197相同。比较花器官发现, AMS971除一个正常的雌蕊外,还有6个梭形的心皮化假性雌蕊。假心皮化雌蕊上部变成近似倒U形的柱头结构区, 下部是完全突变的半开裂心皮, 其上着生4~14个不等的裸露的幼小胚珠; 蜜腺比正常油菜小, 数目为0~4个, 这与AP197没有差异。AMS971的四轮花器官由于突变造成了大小和重量的重新分配。推断AMS为类似拟南芥属B功能缺失的突变体。

Morphology and Anatomy of a New Apetalous Mutant SterileLine in Brassica napus

A new kind of apetalous mutant male sterility line, AMS971, was discovered in apetalous oilseed rape AP197 (Brassica napus). The male-sterile trait was genetically controlled by four pairs of recessive nuclear genes. The AMS971 flower consists of four sepals, six carpelloid stamens without anthers and a normal carpel in the center of the flower. The top to base of the third-whorl carpelloidstamens showed stigmatic papillae-like inversed-U and semi-fusion carpels with 4~14 exposed ovules. Compared with the wild-type, AMS971 showed 0~4 smaller nectarines, which is similar to AP197.Moreover, the size and weight of the floral organ in AMS971 differs from that in AP197. It was deduced that the AMS971 mutant was caused largely by B-class mutation from genes such as Arabidopsis thaliana.