冬小麦穗—茎维管联络结构及其形成过程对幼穗生长发育的影响

本文系统研究了冬小麦穗－茎维管系统的联络特点及其形成过程，分析了其在小麦幼穗发育中所起的作用。结果表明，小麦穗部维管束主要在旗叶节与茎内维管系统联络，其次是倒二节。其联系是逐步完善的。在幼穗的护颖分化－小花分花以前，穗、茎之间缺少维管联络；到雌雄蕊分化期，穗、茎维管系统依靠原形成层束达到初步联络；药隔形成期时，这种联络已比较完善，达到筛管联结；直到四分体形成期时，穗－茎维管系统的联络才发育完善，同

Studies on the Effect of the Formation of the Ear-Stem Vascular Connection Structure on the Growth and Development of the Young Ear in Winter Wheat

The formation of the vascular connection system between the ear and the stem and its influence on the growth and development of the young ear of winter wheat were studied by serial anatomical investigation. The results indicated that about 4 / 5 of the vascular bundles of the ear connected with those of the stem at the 1st node (flag leaf node); only 1 / 5 of them at the 2nd node. The connection developed gradually. No connection was observed at the time of glume and floret differentiation. By the time of differentiation of the primordia of stamen and pistil, the bundles of the ear and the stem were connected through procambium. Then the connection was strengthened when the phloem of the ear joined that of the stem by the time when anthers were formed in the ear. But the fully developed connection structure with both the phloem and the xylem joined together was not completed until the time when meiosis began. Corresponding to the development of the ear-stem vascular system, the dry matter weight of the young ear also went through a series of changes-the stagnant, slow, rapid and very rapid growth stages. The effect of the formation process of the ear-stem vascular system on the differentiation and development of the spikelets, florets and seed set was also discussed.