Abstract:

To explore the effects of radiation of ⁶⁰Co-γ on alfalfa seed seedling root, stem and leaf tissue structure, the seeds of alfalfa were irradiated with ⁶⁰Co-γ irradiation of 0, 600, 900, 1 200 and 1 500 Gy, respectively. Light microscope was used to observe the changes in tissue structure of root, stem and leaf of the seedlings of ⁶⁰Co-γ radiation alfalfa seeds. With increasing radiation doses, there was an increased tendency on alfalfa root epidermis, cortical parenchyma cells, root vascular cylinder, epigenetic native diameter of the catheter, the thickness of stem, the vascular and cortical parenchyma cells of the epidermis, pith diameter blade upper and lower skin, veins projections, leaf, palisade tissue thickness and spongy tissue. Compared with control group, thickness rate of palisade, palisade tissue tense ratio and spongy tissue loose ratio increased under radiation dose of 600 Gy, however, other radiation doses decrease those values. ⁶⁰Co-γ irradiation had different effects on the tissue structure of root, stem and leaf of alfalfa seedlings.

Key words: Alfalfa, ⁶⁰Co-&gamma, irradiation, Tissue structure, Root, Stem and leaf

摘要：

为了探究⁶⁰Co-γ辐射苜蓿种子的幼苗根茎叶组织结构的影响，试验采用剂量分别为0，600，900，1 200和1 500 Gy的⁶⁰Co-γ射线对苜蓿种子进行辐射处理，利用光镜显微镜观察⁶⁰Co-γ辐射苜蓿种子的幼苗根茎叶组织结构产生的变化。随着辐射剂量的增加，苜蓿根的表皮、皮层薄壁细胞和根及维管柱、原生导管和后生导管的直径，茎的表皮和皮层薄壁细胞的厚度及维管束和髓的直径，叶片的上下表皮、叶脉凸起、叶片、海绵组织和栅栏组织厚度均有增加的变化趋势，除辐射剂量为600 Gy时其栅海比与对照组比较增加外，其他辐射剂量的栅海比、栅栏组织结构紧密度和海绵组织结构疏松程度均有减小的变化趋势。⁶⁰Co-γ射线辐射对苜蓿幼苗的根茎叶组织结构产生了不同的影响。

关键词: 苜蓿, ⁶⁰Co-&gamma, 辐照, 组织结构, 根茎叶