摘要
来自小枝梗的1条大维管束和3—6条小维管束进入小穗轴后分校出23—27条小维管束,它们其中2条通向护颖,5条通向外颖,3条通向内颖,4—8条通向浆片,3条通向子房和柱头,6条通向花丝。小穗轴中的小维管束大多被具有多孔的,相互间联络密切的厚壁细胞所包围。通向内外颖的维管束为有限外韧型维管束,木质部与初皮部分开。而通向浆片、花丝子房的维管束的结构较为简单,仅是导管、筛管镶嵌在薄壁细胞中。维管束中的薄壁细胞的细胞质浓,富含线粒体,推测其呼吸旺盛,代谢活跃,在提供能量和促进物质运输方面起重要作用。通往浆片的维管束的结构与颖花开闭的快慢密切有关,凡其中导管、筛管和薄壁细胞少的品种则开颖时间较长。如把这些维管束切断,颖花就不能正常开闭。增温能加速开闭颖过程,而呼吸抑制剂能抑制开颖和闭颖。
One large and 3--6 small vascular bundles from the pedical got into the rachillaand subsequently branched into 23--27 small vascular bundles in a spikelet. Two ofthem went through to empty-glume, five to lemma, three to palea, four-eight tolodicule, three to ovary and stigma, six to filament. Most small vascular bundleswere surrounded by thick-wall cells which were cribellate and connected closely eachother. The bundles to lemma and palea were separated by the xylem and phloem ofthe collateral vascular bundle. The structure of the bundles to lodicules filaments andovarys was simple, and only the vesgels and sieve elements were mosaic between theparenchyma cells. The cytoplasm was thick and the mitochondria were rich in theparenchyma cells. Suggesting that these cells had a high respiratory rate and metabolicactivity, and which played an important role in providing energy and stimulating sub-stance transport. The structure of vascular bundles in lodicules had close relationships with the rateof spikelet-opening and -closing. If variety had fewer vassels, sieve elements andparenchyma cells in the lodicules, its spikelets opening and closing were delayed. If thesevascular bundles were cut off the spikelet would not open and close normally. Increasing temperature could speed up the processes of spikelet opening and closing,because of promoting respiration of parenchyma cells. The processes could be inhibitedby respiratory inhibitor.
出处
《作物学报》
CAS
CSCD
北大核心
1992年第5期331-336,T004,共7页
Acta Agronomica Sinica
基金
国家自然科学基金
关键词
水稻
开花
小穗轴
维管束
Rice
Rachilla
Vascular bundle
spikelet-opening and -closing
