多花勾儿茶是我国集蜜源、观赏和药用等功能为一体的传统珍贵树种,具有较好的生态和经济效益。为优选其高空压条繁殖的最佳条件,提高和完善其无性快繁技术,采用四因素三水平L₉(3⁴)正交试验设计,探究不同基质配比、外源激素种类、外源激素浓度以及环剥宽度对多花勾儿茶高空压条生根的影响,并运用模糊数学隶属函数法和相关性分析法对各项生根指标进行综合评价,探讨4种因素对压条生根的作用机制。结果显示,适宜的基质和外源激素配比可显著促进多花勾儿茶形成愈伤组织并生根,同时可使各项根部指标增加。方差分析和极差分析表明,生根效果存在基质、外源激素和环剥的差异,其中基质配比和外源激素种类是影响各生根指标的最主要因素。综合评价得出,最有利于多花勾儿茶压条生根的条件为:珍珠岩+草炭+蛭石(1∶1∶1)作为基质、NAA作为生长调节剂、NAA浓度为400 mg/L,环剥宽度为10 mm,该条件下愈伤组织诱导率高达(93.33±2.36)%,生根率高达(85.00±4.08)%,(9.67±0.47)d即可在伤口处形成愈伤组织,(14.00±0.82)d开始生根,平均一级根数[(15.44±0.51)根]、平均一级根长[(7.13±0.25)cm]、平均一级根粗[(3.03±0.21)mm]、根鲜质量[(3.29±0.05)g]、根干质量[(0.67±0.04)g]、根系效果指数(5.50±0.06)、平均隶属函数值(0.77)均为最高。该研究可为建立多花勾儿茶快繁体系,推广多花勾儿茶栽培提供理论参考和数据支撑。

Berchemia floribunda(Wall.)Brongn.is a traditional precious tree species in China with functions as a nectar source,ornamental and medicinal source,and has good ecological and economic benefits.In order to optimize the optimal conditions for B.floribunda air layering propagation and to improve the vegetative propagation technology,the L₉(3⁴)orthogonal matrix experiment was performed to explore the effects of different substrate ratios,exogenous hormone types,exogenous hormone concentration and girdle width on rooting of its air layering,subordination function method and correlation analysis method were used to comprehensively evaluate various rooting indices,and the mechanism of these four factors on rooting explored.The results showed that a suitable substrate and exogenous hormone ratio can promote the formation of callus,along with an increase in various rooting indices.Variance analysis and range analysis indicated that the efficiency of air layering was affected by the substrate ratio,exogenous hormone and girdle width,substrates ratio and exogenous hormone types were the two most important factors.Based on a comprehensive evaluation and correlation analysis,it is concluded that the most favorable treatment condition for B.floribunda rooting is:perlite+peat+vermiculite(1∶1∶1)as substrates,NAA is used as an exogenous hormone types with a concentration of 400 mg/L,and the girdle width is 10 mm.Under this treatment,the callus induction rate is as high as (93.33±2.36)%,and the rooting rate is as high as(85.00±4.08)%,(9.67±0.47)days to form a callus at the wound site,(14.00±0.82)days start to take root,average number of first order roots[(15.44±0.51)roots],average length of first order roots[(7.13±0.25)cm],average diameter of first order roots[(3.03±0.21)mm],fresh weight[(3.29±0.05)g],dry weight[(0.67±0.04)g],root effect index(5.50±0.06),average subordinate function value(0.77)were the highest.The results of this study provide theoretical references and data support for establishing a rapid propagation system of B.floribunda and promoting its cultivation.