不同植物生长调节剂对栓皮栎嫩枝扦插的影响

以栓皮栎7年生优势苗木半木质化枝条为材料,采用3种植物生长调节剂(吲哚丁酸(IBA)、萘乙酸(NAA)和生根粉1号(ABT1)),设置0.5、1.0、1.5 g·L~(-1)3个质量浓度,并用清水对照,调查插穗的不定根发生特征、根系发育效果、不同生根时期营养物质质量分数的动态变化。结果表明:不同植物生长调节剂对栓皮栎插穗不定根的发生和根系发育的影响差异显著。IBA处理插穗生根效果整体优于ABT1和NAA;0.5 g·L~(-1)处理对插穗生根影响较小,1.0、1.5 g·L~(-1)处理不仅显著提高了插穗不定根发生和发育效果,还使插穗提前7~15 d生根;所有处理组合中,IBA质量浓度1.0 g·L~(-1)处理插穗,不定根发生和根系发育效果最佳,不定根发生率、生根数、生根指数等生根指标最大,根系生物量、根系总长度、根系总表面积、根系总体积等根系发育指标也最高。IBA可以通过调控不同时期插穗基部可溶性糖质量分数、m(C)∶m(N)变化,影响不定根的形成。初步筛选IBA质量浓度1.0 g·L~(-1)为当前栓皮栎嫩枝扦插繁殖最佳植物生长调节剂处理;根据营养动态变化,分析了插穗生根机理。

Effects of Plant Growth Regulators on the Rooting of Softwood Cutting of Quercus variabilis

Semi lignified branches of 7a superior seedlings of Quercus variabilis were subjected to three kinds of plant growth regulators (Indole butyric acid, naphthalene acetic acid, ABT No.1 rooting powder) with three contents of 0.5, 1.0 and 1.5g·L-1, as well as to water as control.Adventitious root characteristics, root development and the dynamics of nutrient content in the varied rooting periods were explored.The plant growth regulator types significantly affected adventitious root initiation and development of Q.variabilis.IBA yielded the most ideal effect for the rooting of cuttings.The 0.5g·L-1 treatment conferred minor effect on the rooting of cuttings.The 1.0 and 1.5g·L-1 treatments not only benefited adventitious root formation and development, but also hastened rooting fro 7-15d.The combination of IBA with 1.0g·L-1 had the most advantageous to adventitious root formation and root development of cuttings.Cuttings treated with the combination had the greatest rooting rate, adventitious root number and root effective index.Also, it had the greatest root biomass, total root length, total root surface area and total root volume.The mechanisim of IBA promoting the formation of adventitious roots was that IBA effectively regulated the soluble sugar content and the mass ratio of C to N in various rooting stages.The current study trial provided IBA1.0g·L-1 as the the optimal plant growth regulator and concentration for the rooting of Q.variabilis, and preliminarily revealed the rooting mechanism.