矮生杉木的解剖特性

为揭示杉木Cunninghamia lanceolata矮生的原因，以矮生杉木和正常杉木为材料，对其生长特性、枝条和叶片解剖结构进行了比较研究。结果表明:矮生杉木在枝条年生长量方面极显著低于正常杉木，其中矮生杉木主干、主枝年伸长量均值分别为25.54和24.59 cm，正常杉木相应均值分别为89.61和57.52 cm；在枝皮率方面，矮生杉木和正常杉木的均值分别为76.50%和37.70%，差异极显著；在管胞平均面积方面，矮生杉木（241.901 6 μm2）极显著小于正常杉木（308.894 6 μm2），然而，矮生杉木的平均管胞密度（3 375 个·mm －2）却极显著高于正常杉木（2 456 个·mm －2）；矮生杉木的枝条单位长度的叶片数量（主干为14 片·cm －1，主枝为10 片·cm －1）极显著多于正常杉木（主干和主枝均为7片·cm －1）；但两者在栅海比（衡量植物生长势的一个指标）方面无明显差异。图2表3参13

Anatomical characteristics of dwarf Cunninghamia lanceolata

To reveal how dwarfing occurs with Cunninghamia lanceolata（Chinese fir），and clarify the internal structure of both branch and leaf，the anatomical characteristics of a dwarf and a control（a normal tree） were compared with the method of manufacture slice in 2007 and using t-test. Results revealed that the average growth of the trunk （25.54 cm） and branches （24.59 cm） of the dwarf were significantly（P＜0.01） lower than the control （trunk:89.61 cm and branches:57.52 cm）. Furthermore，for the bark，the dwarf average was 76.50%，and the control was 37.70%（P＜0.01）. The average mean area of a tracheid cell for the dwarf （241.901 6 μm2） was significantly（P＜0.01） lower than the control （308.894 6 μm2），however，the average dwarf tracheid density was 3 375 cells·mm －2，whereas the control was significantly（P＜0.01） lower at 2 456 cells·mm －2. For leaf unit length，the dwarf average （trunk:14 leaves·cm －1 and branches:10 leaves·cm －1） were significantly（P＜0.01） greater than the control （trunk or branches:7 leaves·cm －1）；however，there were no difference in the proportion of palisade tissue and spongy tissue. ［Ch，2 fig. 3 tab. 13 ref.］