穗条生根剂育苗基质和季节对西南桦扦插生根的影响

西南桦(Betula alnoides Buch.-Ham.ex D.Don)是我国西南省(区)造林规模最大的乡土珍贵用材树种.西南桦具有材性优良、容易加工、色泽淡红、不易变形等木材特性,是高级家具、室内装修、木地板的优质材料,经济价值甚高.由于目前育苗用种多采自天然次生林,随着西南桦天然资源的日益贫乏,加剧了造林规模不断扩大与供种量逐渐减少的矛盾;而且,实生苗造林的林木个体间遗传变异较大,林分木材单产较低.随着良种选育工作的深入,西南桦人工林向"有性选育,无性利用"路径发展.

Effects of Root-inducing Regulator, Propagation Medium and Season on Rooting of Betula alnoides Cuttings

The cuttings from scion plucking orchard were used to test the combinations of cutting shoots with root-inducing regulators, media and cutting seasons in order to study the effects of different root-inducing regulators (ABT₆ and IBA) and their concentrations, the lignifying degree of cutting shoots, the media types and propagation seasons on rooting ability, rooting number per shoot and rooting length of Betula alnoides. The result showed that tremendous significant differences were observed among different treatments, and the rooting percentage could be higher than 96.67% under the optimal cutting measure when conducted in the season of summer or autumn by using young shoots with apical bud as cutting shoots, treated with a higher concentration of ABT₆ and IBA (800-1 000 mg·kg^-1), and planting in the organic light medium which consisted of 80% carbonized pine bark.