Optimizing environmental conditions for cultivating Lilium davidii var. unicolor scales based on orthogonal design

Abstract

[Objective] In order to provide suitable environmental parameters for large-scale and rapid propagation of Lilium davidii var. unicolor, the effects of three factors, scale layer, temperature and matrix humidity, on the effect of L. davidii scale culture by burying substrate were studied.

[Method] L. davidii scale as the experimental material, L ₉(3 ⁴) orthogonal design was used to treat different expediting culture temperatures, matrix humidity and scale levels, in order to determine the appropriate environmental parameters for L. davidii scale culture and propagation of bulblets. Through the observation and analysis of the indexes such as the scale decay rate, scale differentiation rate, number of bulblets differentiation, scale rooting rate, number of bulblet rooting and transverse diameter (grading indicator) in the process of expediting culture, the effects of substrate burying culture on the formation of small bulbs by different layers of scales was explored.

[Result] In the early stage of expediting culture, the decay rate of A ₁B ₃C ₃ treatment was the highest, reaching 18.67%. In the third week, the average decay rate of all treatments decreased to 1.33%. With the decline of the decay rate of scales, the differentiation rate of scales began to increase gradually, and entered the peak growth period of bulblet. The differentiation rate of scales in each treatment was 44.16%-86.52%. The number of bulblets in A ₁B ₁C ₁ treatment reached the maximum at the third week, which was 238.67. Except for A ₁B ₃C ₃, A ₂B ₃C ₁ and A ₃B ₃C ₂, the rooting rate of scales was 20.58%-63.92%. At the end of accelerated culture, the number of second-grade bulblets in A ₁B ₃C ₃ treatment was 53 bulblets/30 pieces; the number of first-grade bulblets in A ₁B ₁C ₁ treatment was the most, which was 28 bulblets/30 pieces; in A ₃B ₁C ₃ treatment, there were only three-grade bulblets, and the number of bulblets was only 10 bulblets/30 pieces. The third week of accelerated culture was the key period of L. davidiis cale burying culture. At the same time, this stage was also the initial stage of bulblet root development. The results showed that the differentiation of scales was affected by the culture environment of different treatments. According to the range value of each index, the main factor affecting the formation of bulblet was temperature, followed by relative water content of matrix, and the effect of scale level was the least influential. Among the nine treatments, the growth effect of A ₁B ₁C ₁ (outer layer scale+25 °C +60% relative water content of substrate)was the best, at the end of the culture, the decay rate of scales was 0.33%, the differentiation rate of scales was 96.67%, the differentiation number of bulblets was 231.67 bulblets, the rooting rate of scales was 89.67%, and the rooting number of bulblets was 319.33 bulblets.

[Conclusion] In the process of cultivating the scale of L. davidii by burying substrate, the quality and quantity of small bulbs formed by different scales under different environmental conditions are different, and the reproduction efficiency is different. The suitable environmental parameters for the growth of scale media are the external scale+25 °C+60% relative water content of the substrate, which can be widely used in production experiments.

Abstract

摘要：【目的】探究兰州百合鳞片基质埋培过程中不同鳞片层次、催培温度及基质湿度对埋培效果的影响, 为兰州 百合进行规模化快速繁殖提供适宜的环境参数。 【方法】以兰州百合鳞片为试验材料, 选用L ₉(3 ⁴)正交设计表进行不 同催培温度、基质湿度、鳞片层次处理, 以期明确兰州百合鳞片催培繁殖小鳞茎适宜的环境参数。通过催培过程中鳞 片腐烂率、鳞片分化率、小鳞茎分化数、鳞片生根率、小鳞茎生根数及其横径(分级指标)等的观测与分析, 探究基质埋 培对不同层次鳞片形成小鳞茎的影响。 【结果】催培初期, A ₁B ₃C ₃处理腐烂率最高, 达18.67%, 进入3周时, 所有处理的 平均腐烂率下降至1.33%。随着鳞片腐烂率下降, 鳞片分化率开始逐渐上升, 进入小鳞茎生长高峰期, 各处理的鳞片 分化率为44.16%~86.52%, A ₁B ₁C ₁处理在催培3周时小鳞茎分化数达最大值, 为238.67个。除A ₁B ₃C ₃、A ₂B ₃C ₁和A ₃B ₃C ₂ 处理外, 其余各处理的鳞片生根率为20.58%~63.92%。催培结束时, A ₁B ₂C ₂处理二级小鳞茎最多, 达53粒/30片; A ₁B ₁C ₁处理的一级小鳞茎最多, 为28粒/30片; A ₃B ₁C ₃处理只有三级小鳞茎, 且小鳞茎数量仅10粒/30片。催培第3周是 兰州百合鳞片埋培的关键时期, 也是小鳞茎根系发育的初期。不同处理的催培环境均不同程度的影响着鳞片分化情 况, 综合各项指标的极差值大小, 确定影响小鳞茎形成的主要因素为温度, 其次为基质相对水含量, 鳞片层次影响最 小。9个处理中A ₁B ₁C ₁(外层鳞片+25 °C+60%基质相对水含量)小鳞茎生长效果最佳, 催培结束时鳞片腐烂率为 0.33%、鳞片分化率为96.67%、小鳞茎分化数为231.67个、鳞片生根率89.67%、小鳞茎生根数为319.33条。 【结论】兰州 百合鳞片基质埋培过程中不同层次鳞片在不同环境条件下形成小鳞茎的质量和数量均不同, 繁殖效率均有差异。鳞 片基质埋培繁殖适宜的环境参数为外层鳞片+25 °C+60%基质相对水含量, 该技术参数可在生产实践中推广应用。