丹参雄性不育系Sh-B的鉴定与花粉发育过程的解剖学研究

在显微水平上对新发现的丹参雄性不育系Sh-B花药发育过程进行了解剖学观察,并对其花粉活力和结实率进行了鉴定。结果显示:根据花器官及花药的形态、大小以及花丝的长度,可以将Sh-B不育株分为3个不育类型,即Sh-B1、Sh-B2和Sh-B3。这3种不育类型均属于雄性不育,其花丝不到正常可育株的1/2,花药干瘪而瘦小,内无花粉粒或花粉无活力;其根、茎、叶以及种子形态结构与正常可育植株基本相似。产生雄性不育的主要原因有:花粉囊药室内壁纤维层加厚,影响花药壁开裂;小孢子母细胞周围不产生胼胝质或产生的胼胝质很少;绒毡层细胞延迟解体;花粉粒畸形。在其花药发育的小孢子母细胞时期、四分体形成前期、单核期、双核期均可能产生雄性不育的小孢子或花粉粒。

Identification and Pollen Development Anatomy of the Male Sterility Line Sh-B in Salvia miltiorrhiza

The anther development of the newly discovered male sterility line Sh-B in Salvia miltiorrhiza was anatomically examined on microscopic level and the pollen vigor and seed-setting percentage of the line were tested.It was shown that according to the morphologies and sizes of their flowers and anthers and their filament lengths the male sterility plants of Sh-B could be divided into three sterility types,Sh-B_1,Sh-B_2 and Sh-B_3.These three sterility types were male sterility ones and their filament lengths was less than one second of the filament lengths of the normal fertile plants,and their anthers were wrinkled and slight,and contained no pollen grains or pollen grains without vigor;their root,stem and leave and seed morphologies were similar to those of the normal fertile plants.Their male sterility mainly resulted from that fibrous layers of the endothecia in their pollen sacs were thickened and thus their anther wall became difficult to open;there were no or little callose produced around the microspore mother cells and the pollens were distorted;there were male sterility microspores or pollen grains forming at the microsporocyte phase,early tetrad phase,uninucleate phase and binucleate phase in the anther development.