生长调节剂对降香黄檀营养生长与生殖生长的影响

【目的】研究生长调节剂对降香黄檀Dalbergia odorifera营养生长与生殖生长的影响,为不同经营目标的降香黄檀人工林生产提供技术支撑。【方法】以10年生降香黄檀为研究材料,采用随机区组试验设计,通过叶面喷施3种不同浓度的赤霉素(GA3)、多效唑(PP333)和6-苄氨基嘌呤(6-BA),测定盛花期内一年生新梢、花、叶的形态生长和干质量变化,再运用统计分析软件,对各种生长调节剂处理后营养生长和生殖生长的变化规律进行分析。【结果】不同种类和不同浓度的生长调节剂对降香黄檀营养生长和生殖生长的影响差异均达显著水平(P0.05)。叶面喷施200、100 mg·L~(-1)的GA3和500 mg·L~(-1)的6-BA均能显著促进降香黄檀的营养生长,抑制其生殖生长;其中,200 mg·L~(-1)的GA3对生殖生长的抑制效果最理想,施用后其营养枝率比对照显著提高140.84%,花序数显著降低79.41%;100 mg·L~(-1)的GA3对营养生长效果显著,施用后其营养枝枝长、直径、复叶数和单叶干质量分别比对照提高218.08%、120.70%、132.38%和217.33%,且均达显著水平。1 500、2 000 mg·L~(-1)的PP333和50 mg·L~(-1)的6-BA均能显著促进降香黄檀的生殖生长,以2 000 mg·L~(-1)的PP333作用效果较好,处理后其花枝率、花序数量和花序径依次比对照提高73.50%、50.37%和31.30%,且均达显著水平。【结论】降香黄檀人工林培育中,叶面喷施200或100 mg·L~(-1) GA3能显著抑制生殖生长、促进营养生长,有利于大径级木材培育,2 000 mg·L~(-1)的PP333则有利于生殖生长,有利于良种壮苗生产。

Effects of plant growth regulators on vegetative and reproductive growth of Dalbergia odorifera

Objective] To investigate the effects of plant growth regulators on vegetative and reproductive growth of Dalbergia odorifera, and provide useful suggestions for plantation management of D. odorifera with different purposes.Method] We set up a randomized block experiment using 10-year-old D. odorifera. Leaves were sprayed with three different concentrations of gibberellin (GA₃), paclobutrazol (PP₃₃₃) or benzyladenine (6-BA). Changes in morphology, growth and dry weight of 1-year-old branch, flower and leaf at full-bloom stage were measured. The changing patterns of vegetative and reproductive growth after treating with plant growth regulators were investigated using statistical analysis software.Result] Both type and concentration of plant growth regulators caused significant differences in vegetative and reproductive growth of D. odorifera (P<0.05). Foliar application of 200, 100 mg·L^–1 GA₃ or 500 mg·L^–1 6-BA significantly promoted vegetative growth of D. odorifera, while inhibited reproductive growth. Application of 200 mg·L^–1 GA₃ had the best inhibition effect on reproductive growth with the ratio of vegetative branch increased by 140.84% and inflorescence number reduced by 79.41% compared to control (P<0.05). Application of 100 mg·L^–1 GA₃ had the best promoting effect on vegetative growth with the vegetative branch length and diameter, compound leaf number and dry weight of simple leaf increased by 218.08%, 120.70%, 132.38% and 217.33% compared to control (P<0.05). On the other hand, foliar application of 1 500, 2 000 mg·L^–1 PP₃₃₃ and 50 mg·L^–1 6-BA significantly promoted the reproductive growth of D. odorifera. Application of 2 000 mg·L^–1 PP₃₃₃ had the best promoting effect on reproductive growth with the ratio of reproductive branch, the number and diameter of inflorescence increased by 73.50%, 50.37% and 31.30% respectively compared to control (P<0.05).Conclusion] For plantation management of D. odorifera, foliar application of 200 mg·L^–1 or 100 mg·L^–1 GA₃ can inhibit reproductive growth and promote vegetative growth, and should be used for large timber production. Foliar application of 2 000 mg·L^–1 PP₃₃₃ can promote reproductive growth, and should be suitable for selective breeding.