农林废弃物基质对蓝花楹苗木生长效应的影响

以椰糠、稻壳、桉树皮为原料，按照不同体积比例配置15种混配基质，并以黄心土为对照，对16种基质进行理化性质和苗木生长状况的分析比较，通过主成分分析法筛选最佳配比。结果表明：16种基质电导率为0.19~4.63 ms·cm-1，容重为0.18~0.96 g·cm-3，总孔隙度为63.90%~93.33%，pH 值在4.19~6.27之间，不同基质配比差异均达到显著水平。混配基质 S4、S6、S14容重显著低于其他各配比基质及对照组，总孔隙度高于或显著高于其他配比基质，基质 pH 值为中性偏酸，对蓝花楹幼苗生长有较好的促进作用。对苗木各生长性状等指标进行主成分分析，结果表明：S4、S6、S14三种混配基质综合得分较高，适合作为蓝花楹幼苗培育的备选基质，但筛选出的三种混配基质有机质含量、速效氮、速效磷和速效钾含量并不突出，可能物理性质的优劣是蓝花楹幼苗在基质内生长的主要限制因素。

Effects of Agricultural and Forestry Residue Substrates on the Growth of Jacaranda mimosifolia Seedlings

To select high-quality mixed substrates for propagation of Jacaranda mimosifolia seedlings, 15 mixed substrates prepared using combinations of the coir, rice husk and eucalypt mixed in various ratios were trialed for seedling growth. Yellow soil was included as a control treatment. The physical and chemical properties of the substrate mixes were analysed and growth status of J. mimosifolia seedlings in the substrate mixes were compared. The results showed that: electrical conductivity, bulk density and total porosity of the 16 substrate mixes ranged from 0.19 to 4.63 ms·cm-1, 0.18 to 0.96 g·cm-3 and 63.9 to 93.3 % respectively, and their pH’s ranged from pH 4.2 to 6.3, with differences among the 16 substrate mixes for all traits measured being significant. The bulk density of S4, S6 and S14 mixtures were significantly lower than other mixed substrates and also the control substrate while their total porosity were higher than others. All of these physical properties proved beneficial to promoting growth of J. mimosifolia seedlings. Principal component analyses assigned comprehensive scores of 3.39, 3.04 and 2.34 to S4, S6 and S14 substrate mixtures respectively; these three mixtures proved significantly superior to all 12 other mixtures and can be recommended as preferred substrates for cultivation of J. mimosifolia seedlings. Whilst the organic matter, available nitrogen, available phosphorus and available potassium contents of the three superior substrate mixtures (i.e. S4, S6 and S14) were relatively low, substrate physical properties rather than inherent fertility were the main factors limiting growth of J. mimosifolia seedlings in the substrate mixtures included in this trial.