【摘要】 为了研究小麦穗部和颖果维管束的特性,以中筋小麦品种扬麦16为材料,通过光学、电子和荧光显微镜等观察和分析了穗部和颖果中维管束的结构、数目、发育及其相互关系。结果表明:(1)在花后8~28 d内,小穗轴中央维管束被TTC染色很红,随后变浅;从花后第4 d起,小穗轴中央维管束对I2-KI着色,呈色持续至花后24d,其后不呈色。(2)花后1~6 d,颖果腹部维管束未完全分化成型,花后12 d,较完善的输导组织已发育形成,花后15~30 d,腹部维管束发育成熟并发挥物质运输作用,花后36 d,维管束输导功能已基本丧失。(3)花后19 d,颖果维管束中筛分子有典型的伴胞,并形成筛分子-伴胞复合结构,周围有大型的薄壁细胞,伴胞或薄壁细胞的体积比筛管分子大,细胞质浓,线粒体密度大;花后32 d,颖果韧皮薄壁细胞外形不规则,许多细胞壁突出或内陷,大部分韧皮薄壁细胞核解体,线粒体数目变少。(4)穗轴节片维管束排列为内、外两环,外环的维管束较小,位于茎的边缘,内环的维管束较大,周围为基本组织所包围。(5)穗轴节片大维管束数目从下而上逐减,上部和下部节片维管束下降幅度较少,而中部下降较多,但小维管束数目变化与此相反。(6)小穗轴基部维管束为12~13条,每小穗内的第1小花基部维管束为6~7条,第2小花中为5~6条,第3、4小花中为3~4条,第5小花以上各花中均为3条。更多还原

【Abstract】 In order to investigate the characteristics of vascular bundle system in spikes and caryopsis of wheat,the structure,number,development of vascular bundle system in spikes and caryopsis of medium-gluten wheat(Tritium aestivum L.) Yangmai 16 and their relationship were observed via the optical microscope,electron microscope and fluorescence microscope,etc.The main results were as follows:(1) From 8th day to 28th day after flowering,the middle vascular bundle in spikes were dyed red deeply reaction to TTC,later,lighter;The middle vascular bundle in spikes were dyed reaction to I2-KI from 4th day to 24th day after flowering,later,little dyed.(2) The vascular bundle in caryposis abdomen appeared not entirely formed within 6 days after flowering,the fully differentiated vascular bundle formed at 12th day after flowering.From the 15th to 30th day after flowering,it matured completely and played an important roles in substance transport,its transport functions lost at about 36th day after flowering.(3) At the 19th day after flowering,some SEs had typical CC and SECC ccomplex formed.There were big thin-wall cells around it.Compared to SE,the CC or thin-wall cell had larger volume,thicker cytoplasm and denser mitochondrion;At the 32th day after flowering,the outer shape of thin-wall cells took on abnormity,many cell walls extruded or concaved,the cell nucleus disjointed,the numbers of mitochondrion decreased.(4) The vascular bundles of rachis proglottis were arranged with two annulus from outer to inner.The vascular bundles in outer annulus in the stem brim were smaller,while in the inner annulus bigger,and surrounded by the around basis tissues.(5) The number of large vascular bundles in the rachis proglottis decreased form base to top,that of top and base decreased less,but that of middle decreased more,while the small vascular bundles was the reverse.(6) There were 12~13 vascular bundles in rachilla base,6~7 in the first flower base of every spikelet,5~6 in the second flower base,3~4 in the third or fourth flower base,3 at the fifth or upwards flowers.更多还原