不同截干高度下米老排促萌效果

为完善米老排 Mytilaria laosensis 采穗圃营建技术，重点探究不同截干高度对 2 年生米老排无 性系苗促萌效果的影响。试验共设置 3 种截干高度处理，即 20（T1）、30（T2）、40 cm（T3），采取主干 和萌条 2 次截干法。结果表明：第一次截干后 T2 和 T3 的萌芽数和萌条数显著大于 T1，且 T3 ＞ T2 ＞ T1， T3 平均每株萌芽数和萌条数分别达 10.72 个和 4.17 条，但 T1 的萌条转化率最高；二次截干后，各处理间 萌条数差异不显著。截干高度对萌条基径影响不显著，对二次截干后的萌条长度影响显著，但 T1 的萌条 基径均最大，其萌条质量相对来说更优。两次截干后 T1 的单位萌条数均极显著大于其他两个处理，其促 萌效果最佳，且越靠近根部的萌条，其幼态化程度也越高，分化能力越强。综合来看，截干高度 20 cm 更适合米老排的截干促萌。

Promoting Effect of Mytilaria laosensis under Different Cutting Heights

In order to improve the construction technology of Mytilaria laosensis cutting orchard, focused on the effects of different cutting heights on the effect of 2-year-old M. laosensis asexual seedling sprouts promotion effect. A total of three cutting height treatments were set in the test, namely 20 cm (T1), 30 cm (T2), and 40 cm (T3), taking trunk cutting and twice cutting methods of the sprouts. The results showed that the number of buds and sprouts of T2 and T3 were significantly greater than T1 after the first cutting, and T3>T2>T1. The average number of buds and sprouts per plant reached 10.72 and 4.17 of T3, respectively, but T1 transformation ratio of sprouts is the highest. After the second cutting, the difference in the number of sprouts between treatments was not significant. The cutting height has no significant effect on the base diameter of the sprouts, and has a significant effect on the length of the sprouts after the second cutting. However, T1 has the largest base diameter of sprouts, and its quality is relatively better. The unit number of sprout of T1 was significantly greater than that of the other two treatments after two cuttings, and the effect is better of the promoted sprouts. And the closer to the root, the higher the degree of juvenation and the stronger the differentiation ability. Taken together, the cutting height of 20 cm is more suitable for the cutting and sprout promoting of M. laosensis.