Development of new cambial marking method by using high DC volage pulse.

将直流高压脉冲应用于树木形成层，建立了一种有效的形成层标记方法来估计热带无年轮树木的生长情况。此外，还对树木形成层的生物阻抗进行了监测，以估计形成层活性的季节变化。温带树种经300 ~ 500 v处理后，形成了异常的细胞和组织，不同树种组织形成的异常程度不同，但观察到共同的特点：(1)形成了厚壁血管素和木纤维，(2)射线细胞切向行增加，形成了形状异常的射线薄壁细胞，(3)薄壁细胞中形成了有色物质。阻抗值呈现季节变化，可能反映了形成层活性的差异。

DC high voltage pulse was applied to tree cambium to develop an effective cambial marking method for estimating tree growth of ring-less tropical trees. In addition, bio-impedance of tree cambium was also monitored for estimating seasonal changes of cambial activity. Temperate tree species formed abnormal cells and tissues by treating 300-500 v. The degree of abnormal tissue formation was different by species, but common features were observed as follows: (1) formation of thick-walled vessel element and wood fibers, (2) increase in tangential row of ray cells, and formation of abnormal-shaped ray parenchyma cells, and (3) formation of colored-substances in parenchyma cells. The value of impedance showed seasonal changes, probably reflecting the difference of cambial activity.