用根箱法研究毛竹实生苗根系构型

Study on root-system architecture of Phyllostachys edulis seedlings by rhizobox method

运用根箱法研究了毛竹实生苗的根系构型特征，结果表明：毛竹实生苗没有明显主根，基部形成4～5条不定根；根宽深比为0.682，根宽小于根深；根长、根系数量、根表面积、根体积与根系平均直径在不同土层中的分布存在极显著差异，根长、根系数量、根表面积与根体积集中分布在0～20 cm土层，占总量64.2%～71.66%，随土层加深，各指标均下降，根系平均直径最大值、最小值分别出现在0～10 cm、20～30 cm土层；水平方向毛竹实生苗根系干重的最大值出现在以竹苗为中心0～5 cm范围土层内，随着距离的增加逐渐减少；垂直方向上，84.6%根系干重集中分布在0～20 cm土层，随土层加深，根量减少，呈“T”形分布状态。

The root-system architecture of Phyllostachys edulis seedlings was studied by using root box method. The results show that the main roots of P. edulis seedlings were not obvious, and four or five adventitious roots were formed from the base of seedlings;the ratio of width to depth of P. edulis seeding root was 0.682, the width was less than depth;the roots’ indexes of length, number, surface area, volume and average diameter in different soil-layers had extremely remarkable differences;the root length, number, surface area and volume concentrated in 0-20 cm soil, they accounted for 64.2%-71.66%of the total amount, those root indexes decreased as the depth increased;the maximum and minimum of average diameter of roots appeared in 0-10, and 20-30 cm soil-layers respectively;the maximum dry weight of P. edulis seedling roots in the horizontal direction occurred in the soil-layer of 0-5 cm, the dry weight decreased as the depth increased;the dry weight of seedling roots （84.6%of the total dry weight） in the vertical direction concentrated in the soil-layer of 0-20 cm, the dry weight decreased as the depth increased, showed a characteristic of T-shape distribution.