对于硬枝扦插不易生根的树种,如毛白杨,可以利用其绿枝扦插易于生根的特点,在塑料棚中高温、高湿条件下,进行绿枝扦插以加速繁殖。1984年5—7月,我们进行了毛白杨绿枝扦插试验,得到最高生根率95％的结果,现介绍如下。一、材料与方法于生长季节,剪取1—2年生毛白杨苗木当年侧枝新梢作插穗,插穗长15—20厘米,保留中上部叶片。将插穗基部分别在吲哚丁酸(IBA)或萘乙酸(NAA)10000、5000、1000、500、100和0(对照)ppm 的酒精溶液中速蘸5—10秒,插于塑料棚中的沙床上,每个处理不少于50个插穗。记录插穗生根率、生根数和根长。用人工弥雾使塑料大棚内空气湿度达90—95％,气温保持在20— For hardwood cuttings not easily rooted species, such as Populus tomentosa, you can use the characteristics of its easy to rooting of green shoots, plastic shed in the high temperature and humidity conditions, the green branch cutting to speed up reproduction. May-July 1984, we conducted a poplar cuttings green branch test, the highest rooting rate of 95% of the results are presented below. First, materials and methods In the growing season, cut 1-2 year old poplar young shoots then cuttings, cuttings 15-20 cm long, retaining the upper leaves. The cuttings were dipped briefly in alcoholic solutions of indole butyric acid (IBA) or naphthaleneacetic acid (NAA) at 10,000, 5000, 1000, 500, 100 and 0 Sand bed, each handle not less than 50 cuttings. Record cutting rooting rate, rooting number and root length. Use artificial mist to make plastic air humidity within the greenhouse reached 90-95%, the temperature maintained at 20-