以芳樟（Cinnamomum camphora var. linaloolifera Fujita）195号无性系1年生扦插苗为研究对象，采用四元二次回归正交旋转组合设计（1/2实施）对褐球固氮菌（Azotobacter chroococum Beijerinck）、巨大芽孢杆菌（Bacillus magaterium de Bary）、胶冻样芽孢杆菌（B. mucilaginosus Krassilnikov）和枯草芽孢杆菌（B. subtilis Cohn）不同施用量（在5.5 kg盆栽土中分别施用2×10⁹、3×10⁹、4×10⁹、5×10⁹和6×10⁹ CFU微生物菌剂）组合处理下芳樟叶和枝的鲜质量及其比值、精油含量及精油产量进行了比较，以4种微生物菌剂的施用量为自变量（X）、精油产量为因变量（Y）进行了回归方程拟合分析和显著性检验，并对影响芳樟精油产量的微生物菌剂进行了单因子效应分析。结果表明：与对照组（未施用微生物菌剂）相比，多数处理组的枝精油含量升高，23个处理组的其余5个指标均升高，并且多数处理组的上述指标显著升高。获得的回归方程为Y=0.686+0.064X1-0.116X₂+0.200X₃-0.122X₄+0.002X₁²+0.036X₂²+0.106X₃²-0.032X₄²+0.024X₁X₂+ 0.116X₁X₃-0.086X₁X₄，其显著性检验P值为0.001 8。单因子效应分析结果表明：芳樟精油产量与褐球固氮菌施用量（X1）和胶冻样芽孢杆菌施用量（X₃）呈正相关，与巨大芽孢杆菌施用量（X₂）和枯草芽孢杆菌施用量（X₄）呈负相关。在供试处理组中，T3组（褐球固氮菌、巨大芽孢杆菌、胶冻样芽孢杆菌和枯草芽孢杆菌在5.5 kg盆栽土中的施用量分别为5×10⁹、3×10⁹、5×10⁹和3×10⁹ CFU）的精油产量最高（1.56 g），最接近根据上述回归方程计算的精油最高产量（1.72 g）。研究结果显示：微生物菌剂能够有效促进芳樟生长和精油积累（1/2实施）。

 Taking one-year-old cutting seedlings of No. 195 clone of Cinnamomum camphora var. linaloolifera Fujita as research objects， leaf and branch fresh masses and their ratio， essential oil content， and essential oil yield of C. camphora var. linaloolifera were compared under combination treatments with different application amounts （applying 2×10⁹， 3×10⁹， 4×10⁹， 5×10⁹， and 6×10⁹ CFU microbial agents in 5.5 kg potting soil， respectively） of Azotobacter chroococum Beijerinck， Bacillus magaterium de Bary， B. mucilaginosus Krassilnikov， and B. subtilis Cohn by quadratic regression orthogonal rotational combination design with four factors（1/2 implementation）， regression equation fitting analysis and significance test were performed by taking application amount of four microbial agents as independent variable （X） and essential oil yield as dependent variable （Y）， and the single factor effect analysis on microbial agents affecting essential oil yield of C. camphora var. linaloolifera was performed. The results show that compared with the control group （without applying microbial agents）， essential oil content in branch of most treatment groups increases， other five indexes of twenty-three treatment groups all increase， and above indexes of most treatment groups increase significantly. The obtained regression equation is Y=0.686+0.064X1-0.116X₂+0.200X₃-0.122X₄+0.002X₁²+0.036X₂²+0.106X₃²-0.032X₄²+0.024X₁X₂+ 0.116X₁X₃-0.086X₁X₄， its significance test P value is 0.001 8. The result of single factor effect analysis shows that there are positive correlations of essential oil yield of C. camphora var. linaloolifera with application amount of A. chroococum （X₁） and that of B. mucilaginosus （X₃）， and negative correlations with application amount of B. magaterium （X₂） and that of B. subtilis （X₄）. Among test treatment groups， the essential oil yield of T3 group （the application amounts of A. chroococum， B. magaterium， B. mucilaginosus， and B. subtilis in 5.5 kg potting soil are 5×10⁹， 3×10⁹， 5×10⁹， and 3×10⁹ CFU， respectively） is the highest （1.56 g）， which is the closest to the highest yield （1.72 g） of essential oil calculated by above regression equation. It is suggested that microbial agents can effectively promote growth and essential oil accumulation of C. camphora var. linaloolifera.