为优化降香黄檀(Dalbergia odorifera)扦插繁殖技术体系、解决其生根效率低下的技术问题,采用双因素试验,探究不同浓度(200、400、600、800 mg/L)和浸泡时间(10 s、1 min、30 min、60 min)下复合生长调节剂(IAA+NAA)对降香黄檀扦插繁殖效果的影响。结果表明:1)激素浓度、浸泡时间及二者交互作用对降香生根率、根干质量、总根长等指标均具有极显著影响(P<0.01)。激素浓度对多项指标均具有非线性调控效应,其中400 mg/L处理在多项指标中表现最优:400 mg/L+10 s处理的生根率达92.5%,根干质量为0.035 g,最大根长及新梢干质量亦显著优于其他处理。2)浸泡时间对生根的影响具有浓度依赖性:低浓度(200 mg/L)下延长时间可促进生根,而中高浓度下短时处理(10 s~1 min)更优,长时间浸泡(60 min)则显著抑制生长。3)相关性分析表明,生根率与最大根长、总根长、新梢数及新梢干质量均呈极显著正相关(P<0.01),与根干质量呈显著正相关(P<0.05),根干质量与新梢干质量也呈极显著相关,表明根系与地上部分生长之间存在协同促进关系。4)主成分分析表明,400 mg/L+10 s为最优处理,其得分显著高于其他组合。明确“中浓度-短时间”为降香黄檀扦插繁殖的高效策略,为该树种的规模化无性繁殖提供了理论依据与技术参数。

To optimize the cutting propagation technical system of Dalbergia odorifera and resolve the technical bottleneck of its low rooting efficiency,a two-factor experiment was conducted to investigate the effects of compound growth regulators(IAA+NAA)on its cutting propagation.The results demonstrated that:1)Hormone concentration,soaking time,and their interaction exerted highly significant effects(P<0.01)on key growth parameters,including rooting rate,root dry weight,and total root length.Further analysis revealed a nonlinear response of most measured traits to hormone concentration,with the 400 mg/L treatment yielding optimal performance across multiple indicators.Specifically,the C2T1 treatment(400 mg/L for 10 s)resulted in a rooting rate of 92.5%,a root dry weight of 0.035g,and significantly enhanced total root length,number of new shoots,and shoot dry weight compared to other treatments.2)The impact of soaking time was concentration-dependent:extended soaking improved rooting at low concentration(200 mg/L),whereas shorter durations(10 s to 1 min)were more beneficial at medium to high concentrations,and prolonged soaking(60 min)strongly inhibited growth.3)Correlation analysis indicated that rooting rate was significantly positively correlated with root dry weight(P<0.05)and highly significantly correlated with maximum root length,total root length,root number,shoot number,and shoot dry weight(P<0.01).Additionally,root dry weight was also highly significantly correlated with shoot dry weight,suggesting a synergistic relationship between the root system and aboveground growth.4)Principal component analysis(PCA)revealed that C2T1 as the optimal treatment,with its comprehensive score significantly surpassing those of other combinations.In conclusion,this study establishes a “medium concentration-short duration” strategy as highly effective for the cutting propagation of D.odorifera,providing a theoretical insights and practical parameters for large-scale asexual propagation of this valuable species.