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邻近江西分宜种源试验林 ,选择一片完整的鹅掌楸 (Liriodendronchinense)近成熟人工林 (1981年栽植 ) ,抽取 33棵样本株 ,分年轮测定了木材基本密度和纤维长度。鹅掌楸木材基本密度径向变异模式呈“V”曲线 ,纤维长度径向变异遵从指数曲线模式 ,研究结果与Harold和Taylor等人关于北美鹅掌楸木材性状径向变异的描述基本一致。幼成龄年 -年相关分析结果表明 ,当大于等于 5个胸高处年轮时 (约相当于树龄 7a生 ) ,两性状幼成龄材相关均显著。利用鹅掌楸 15个 7a生种源材性数据平均值与 17a生人工林材性数据的前 5个年轮段数据 ,进行比较与拟合 ,2组数据在共有时段内成线性关系 ,且回归系数B1 均接近于 1,变化趋势基本平行 ,分析结果表明鹅掌楸幼成龄变异规律从整体上来说存在可比性 ,其材性早期选择是可行的。探讨了平均龄龄相关系数 (MACC)随年龄间隔 (AI)的变异趋势 :两性状MACC与年龄间隔成反比 ,即年龄间隔越大MACC越小 ,这可能源于基因表达的时间控制理论 ,这种变化关系在其他的树种研究中也被提到过。该分析结果从另一侧面阐明了鹅掌楸主要木材性状的早期选择是可行的 ,但选择年龄不宜小于 7a生
Near the Jiangxi Fenyi provenance test forest, a complete mature Liriodendronchinense plantation (planted in 1981) was selected. 33 sample plants were selected and the basic density and fiber length of the wood were determined by annual rings. Variations of radial density of basic density of Tiriium virgatum showed a “V” curve, and the radial variation of fiber length followed the exponential curve pattern. The results are in good agreement with the descriptions by Harold and Taylor et al. On the radial variation of wood traits of Liriodendron tulipifera. The results of juvenile-years correlation analysis showed that there was a significant correlation between juvenile-aged materials of both traits when the annual growth rate was greater than or equal to 5 thoracic anodes. Based on the data of 15 species of 7-year-old germplasm resources of Liriodendron and the data of the first 5 years of 17-year-old plantation data, the data of 2 groups were linearly correlated in the common period The regression coefficients B1 are close to 1, and the trend of change is basically parallel. The analysis results show that the law of juvenile age variation of Liriodendron chinense is comparable as a whole, and the early selection of its material is feasible. The variation trend of average age-related coefficient (MACC) with age interval (AI) was discussed: the MACC of two traits is inversely proportional to the age interval, that is, the larger the age interval, the smaller the MACC, which may be due to the time control theory of gene expression The species relationship has also been mentioned in other tree species studies. The results of the analysis illustrate from another aspect that the early selection of the main wood traits of Liriodendron is feasible, but the age of selection should not be less than 7a