粳稻颖果石蜡切片中染色时间的摸索及其解剖结构的观察

Research on the Dyeing Time of the Caryopsis of Japonica Rice in Paraffin Section and Its Anatomical Structure

以典型粳稻品种辽粳294和盐丰47花后不同天数的颖果为试材,对传统石蜡切片技术中固绿步骤的染色时间进行试验。结果表明,花后不同天数的颖果染色最佳时间差异很大,即发育的前期颖果幼嫩,固绿染色时间反而较长,需要20～25s,而后期随着颖果逐渐充实,染色时间相对缩短,只需10～20s。利用改良后的方法,对颖果结构进行观察发现,花后第4天～第22天颖果果皮结构石蜡切片完整清晰,第4天～第12天颖果整体结构完整清晰,染色分明。观测表明,两品种颖果背部维管束截面均近似椭圆形,从整体上看,两品种颖果背部维管束表现为从基部到顶部由粗到细的象牙形管—束状结构,由居中的导管束和周边的若干筛管束构成。通过改进的切片方法可以对颖果的解剖结构进行清晰地观察。

Caryopsis of typical Japonica rice Liaojing294 and Yanfeng47 at the different days after flowering （DAF） was used as materials to select the best dyeing time for safraine-fast green staining in traditional paraffin section. Differences were observed for the dyeing time of carysis at different DAF. For example, the dyeing time of fast green （20 - 25s） is much longer for the young caryopsis at early growth stage, while that of old caryopsis plumpness at later stage was short （10 -20s）. Then the structure of earyopsis was investigated by using the improved method. The pericarp structure at 4 - 22 DAF and the whole structure at 4 - 12 DAF were clear and complete. The section of dorsal vascular bundle was all near ellipse, the dorsal vascular bundle, which was composed of centered vessel and circumjacent sieve tube, showed wide to thin from bottom to top. Using this improved method the anatomical structure of caryopsis could be visible clearly.