| 摘要: |
| 【目的】比较研究中山杉302（Taxodium hybrid Zhongshanshan 302，T. distichum ♀×T. mucronatum ♂）与母本落羽杉树皮解剖构造及周皮形成的差异，为中山杉品种选育提供依据。【方法】以25年生的同龄中山杉302和落羽杉为研究对象，采用包埋切片技术和组织离析方法观察树皮解剖构造及周皮的形成。【结果】（1）中山杉302韧皮部细胞组成类型与落羽杉相同，二者轴向系统均包括韧皮纤维（PF）、筛胞（Se）和韧皮薄壁细胞（PP）。中山杉302的细胞排列方式多于落羽杉，其细胞排列方式多数为“PF-Se-PP-Se-PF”和“PF-Se-PP-Se-PP-Se-PF”，少数为“PF-Se-PP-Se-PP-Se-PP-Se-PF”，偶见“PF-Se-PP-Se-PP-Se-PP-Se-PP-Se-PF”；而落羽杉韧皮部细胞排列方式多数为“PF-Se-PP-Se-PF”，少数为“PF-Se-PP-Se-PP-Se-PF”。（2）中山杉302和落羽杉周皮细胞组成及排列类型相同，均为2层木栓层细胞，1层木栓形成层细胞，1～2层栓内层细胞。（3）中山杉302和落羽杉每年均产生新的周皮，但形成时间及位置不同，中山杉302于8月中旬韧皮部薄壁细胞出现脱分化，8月底木栓形成层向外分生出2层木栓层细胞，向内分生出1～2层栓内层细胞，周皮产生位置距上一年周皮约5～10层韧皮纤维带；而落羽杉7月中旬韧皮部薄壁细胞出现脱分化，7月底木栓形成层向外分生出2层木栓层细胞，向内分生出1～2层栓内层细胞，周皮产生位置距上一年周皮约10～15层韧皮纤维带。【结论】中山杉302和落羽杉韧皮部细胞组成类型相同，细胞排列方式相似；周皮细胞组成及排列类型相同；新生周皮产生时间较落羽杉更晚，产生位置较落羽杉更近。 |
| 关键词: 中山杉 落羽杉 韧皮部 周皮 解剖构造 |
| DOI： |
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| 基金项目:国家自然科学基金项目（31971585） |
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| Comparison on bark anatomical and periderm formation of Taxodium hybrid Zhongshanshan 302 and Taxodium distichum |
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LI Congcong,ZHENG Xinxin,PAN Biao,et al
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| Abstract: |
| 【Objective】The study compared bark anatomical structure and periderm formation between Zhongshanshan 302 and T. distichum to provide basis for the breeding of T.Zhongshanshan 302.【Method】Selecting 25-year-old Zhongshanshan 302 and T. distichum as research plants, the paraffin embedded and Franklin dissociation methods were used to analyze bark anatomical and periderm formation.【Result】（1） Cell composition types in secondary phloem of Zhongshanshan 302 was the same as T. distichum,both including phloem fiber (PF),sieve cell (Se) and phloem parenchyma cell (PP) in axial system.Zhongshanshan 302 had more cell alignment than T. distichum.The alignment of phloem cells in Zhongshanshan 302 was mostly “PF-Se-PP-Se-PF” and “PF-Se-PP-Se-PP-Se-PF”,with a few “PF-Se-PP-Se-PP-Se-PP-Se PF” and occasional “PF-Se-PP-Se-PP-Se-PP-Se-PP-Se-PF”.While,the alignment of phloem cells of T. distichum was mostly “PF-Se-PP-Se-PF” with a few “PF-Se-PP-Se-PP-Se-PF”. （2） The cell types and cell alignment in periderm of Zhongshanshan 302 were the same as T. distichum,and they all had 2 layers of cork layer cells,1 layer of phellogen cells,and 1-2 layers of phelloderm cells.（3） Zhongshanshan 302 and T. distichum produced new periderm each year,with differences in formation time and location of periderms.Parenchyma cells of Zhongshanshan 302 dedifferentiated in the middle of August,and the phellogen divided two layers of cork cells outward and one or two layers of phelloderm inward at the end of August.The distance between new periderm and the periderm in previous year was about 5-10 layers of phloem fiber.Parenchyma cells of T. distichum dedifferentiated in the middle of July,and the phellogen divided two layers of cork cells outward and one or two layers of phelloderm inward at the end of July.The distance between new periderm and the periderm in previous year was about 10-15 layers of phloem fiber.【Conclusion】Zhongshanshan 302 and T. distichum had same phloem cell types,similar cell alignment and same periderm cell composition types and alignment.Zhongshanshan 302 produced new periderms later than T. distichum,and the distance between new periderm and the periderm in previous year of Zhongshanshan 302 was closer than that of T. distichum. |
| Key words: Taxodium hybrid Zhongshanshan 302 Taxodium distichum phloem periderm anatomical structure |
