冬小麦根系各级分枝形成及其解剖结构研究

Formation of the Root Branches of Different Orders and Their Anatomical Structures in Winter Wheat

从池栽、盆栽和大田取根 ,系统观察高产小麦各级分枝根形成和解剖结构。结果表明 ,小麦根系经由分枝 ,初生根可达 6级 ,次生根可达 5级。各级分枝根解剖结构的差异主要是皮层细胞层数和中柱维管束数目的不同。小麦分蘖期以后继续发生的根 ,如果土壤条件适宜 ,植株生长健壮 ,其根皮层可一直维持正常状态到抽穗期 ,抽穗后根皮层将逐渐萎缩。高级别细根的结构比较简单 ,各部位细胞排列无序 ,但扁平的内皮层细胞总是清晰可辩。距发根部位较近的次生根 。

The development and anatomical structures of the root branches of different orders in winter wheat were studied systematically. The results revealed that the root system could develop 6 orders of primary roots and 5 orders of secondary roots. Differences in the anatomical structures of the various orders of root branches were expressed mainly by the number of layers of cortex cells and the number of vascular bundles. Cortex in root branches developed after the tillering stage could remain normal until the heading stage so long as the plant remained vigorous and the soil and water conditions optimal. After that, it would become withered gradually and finally shed away. The structure of thin roots of higher orders was comparatively simple. The arrangement of the cells was mostly irregular, but the inner cortex cells could always be seen clearly. In secondary roots developed near the tillering node, the structure of the cortex developed somewhat uniquely.