樟树组培苗轻基质育苗技术研究

Light Substrate Nursery Technique for Tissue-cultured Seedlings of Cinnamomum camphora

为提高乡土阔叶树种樟树Cinnamomum camphora的育苗效率,以其新选育的优良无性系组培苗为材料,配置6种以泥炭为主要成分的轻基质组合,开展基质配比、容器规格、空气切根和施缓释肥试验。结果表明,基质配比对苗高、地径、高径比、SPAD值与存活率均有显著影响;泥炭中添加蛭石、木糠或珍珠岩均能显著改善育苗效果,同时添加木糠和珍珠岩时效果最佳;而泥炭中添加椰糠的效果与对照100%黄心土近似,明显劣于其他基质。大穴盘组培苗的苗高、地径、SPAD值和存活率均显著高于小穴盘,但高径比不受容器规格影响;空气切根能明显促进地径生长,抑制主根生长,加快侧根和须根生长,使根系更发达;缓释肥处理能显著提升苗木高生长、高径比和SPAD值,但对存活率影响不大。

In order to promote the seedling nursery efficiency for the native broadleaf tree Cinnamomum camphora, 6 combinations of light substrates were designed for analyzing the effects of substrate composition, container size, air-cutting and slow-release fertilization on a genetically-selected clone of seedlings. The substrate compositions had significant influences on height（HT）, basal diameter（BD）, HT-to-BD ratio, SPAD value and survival rate. A single addition of vermiculite, perlite or sawdust into peat soil obviously improved the seedlings＇ performance, and the synchronous supplement of both sawdust and perlite achieved the optimal results. While the complement of peat soil with coconut dust resulted in similar growth situation with 100% yellow soil, which was apparently inferior to other light substrates. Larger containers led to an increase in the growth traits, SPAD value and survival rate when compared with smaller ones, but had little impact on HT-to-BD ratio. Air-cutting induced an increment of basal diameter, an inhibition of main root extension, faster growth of lateral roots and fibrous roots, and occurrence of more developed root system. Slow-release fertilization up-regulated the height, HT-to-BD ratio and SPAD value, but exerted little influences on survival rate.