马尾松间伐材立木充脂研究（Ⅱ）──百草枯充脂扩大试验

Chemical Treatments of Pinus masssoniana Stumpage to Induce Light Wood (Ⅲ)-Parquat treatments for more sumples

试验再次表明百草枯是马尾松间伐材立木充脂的良好药剂．用１％～４％的百草枯水溶液对马尾松间伐材立木进行充脂处理，１５个月后充脂长度为１～２．８ｍ，单割沟处理的与双割沟处理的２ｍ长木段的苯－醇抽出物平均含量分别为６．５％～８．２％和１０．９％～１２．１％，比对照树分别增加９３％～１４２％和２２４％～２５８％。木段平均苯－醇抽出物含量的净增值，双割沟的比单割沟的净增１倍左右，近似为两个单割沟的加和。

Paraquat is once more proved to be one of the good chemicals to induce light wood for Pines massoniana Lamb.stumpages.Before intermediat cutting the stumpages were treated with 1%～4% paraquat solution and harvested after 15 months. The length of induced light wood was from 1.0 m to 2.8m. The average amounts of the benzene-alcohol extracts of the 2. 0m induced stems were 6. 5%～ 8. 2% in single cut treatments and 10. 9%～ 12.1% in double cut treatments,showed 93% ～ 142% increase and 224% ～ 258% increase respectively above the controls.The net increase of the extracts in double cuts treatments was about twice as large as that in single cut treatments, equal to the plus of the two single cut treatments.