白车轴草和紫花苜蓿根瘤的显微及超微结构

通过对白车轴草(Trifolium repens Linn.)和紫花苜蓿(Medicago sativa Linn.)根瘤的显微及超微结构进行观察，发现其根瘤显微结构都由4部分组成，由外向内依次为：保护层、皮层、鞘细胞层和中心组织(侵染组织)。在中心组织的侵染细胞中，分布有大量的线粒体、高尔基体、核糖体及内质网，白车轴草根瘤侵染细胞中的细菌圆形或椭圆形，有明显的周膜、细菌细胞壁和质膜，在细菌发育过程中，周膜活动旺盛，有时相邻细菌的周膜发生融合，在周膜附近常分布有大量的内质网、高尔基体以及高尔基体小泡，似与周膜融合有关。紫花苜蓿细菌椭圆形、长棒形，甚至有的细菌呈分枝状。二者细菌细胞质中分布着大量的核糖体和纤维状的核物质。在白车轴草中还有染色很深的多聚磷酸盐颗粒。

The structure of root nodules in Trifolium repens and Medicago sativa

The structure of root nodules in Trifolium repens Linn. and Medicago sativa Linn. were studied by methods of paraffin-sectioning and ultra-thin-sectioning. the nodules were composed of four parts,ecto-entad they were:the protect layers,cortex,sheath cell layers and center tissue (tissue infected). In the infected celis of center tissue,there were a lots of mitochondron,Golgi bodies and endoplasmic reticulum. The bacteroids in Trifolium repens were round or oblong,which had distinct peribacteriod membranes,cell wall and plasma membrane,the peibacteriod membranes were active during the development of bacteriods. The peribacteriod membranes of neighorbing bacteriods where there were many endoplasmic membrane, Golgi bodies and vesicles fused together. While the bacteriods in Medicago sativa were oblong, linear-clavate, or branched. There were lots of ribosomes and fibrilsome nuclei materials in bacteriods of both species.